USATESTPREP Biology (Evolution)

Charles Darwin was credited for writing the biological theory of __________________. The organisms that were used for the basis of his studies were ___________________. A) evolution by natural selection, sweet peas B) inheritance by independent assortment, sweet peas C) evolution by natural selection, Galapagos finches D) inheritance by independent assortment, Galapagos finches evolution by natural selection, Galapagos finches. Darwin observed bill differences in Galapagos finches, depending on the food source on different islands and wrote the theory of evolution by natural selection.

C) evolution by natural selection, Galapagos finches

How can a geological time scale BEST be reconstructed? A) comparing vestigial structures in living species B) comparing homologous structures in living species C) examining homologous structures in fossil remains D) examining the written records of scientists from past cultures examining homologous structures in fossil remains It is possible to get an idea of how things change and evolve by comparing how fossils change over time.

C) examining homologous structures in fossil remains

Biotechnology has helped produce crops that are resistant to certain pests, crops that produce high yields, and more nitrogen-efficient crops. What is a negative impact that bioengineered plants may have on the environment? A) Beneficial insects may be adversely affected. B) Plants have an increased resistance to insect pests. C) There is an increased need for inorganic fertilizers. D) Genetically engineered plants may have a longer shelf life. Beneficial insects may be adversely affected. While some insects are plant pests, many others a necessary to pollinate the flowers of plants that eventually give us fruits, vegetables, and seeds for human use. Bioengineered plants often require less water, fertilizers, pesticides, and the use of herbicides.

A) Beneficial insects may be adversely affected.

A fossil of a fern and other large-leafed plants were found in an area of Alaska. What does this suggest about this area in Alaska? A) A forest is now covered with snow. B) A farm was once located in the area. C) The area once had a warmer climate. D) Prehistoric man ate large-leafed plants. The fossilized fern suggests the area once had a warmer climate.

C) The area once had a warmer climate.

The theory of endosymbiosis suggests that chloroplasts and mitochondria were once free-living prokaryotes, that were engulfed by larger prokaryotic cells. Eventually, this relationship lead to the development of eukaryotic cells with cellular organelles. These organelles included mitochondria, and in some cases, chloroplasts. The endosymbiosis theory is supported by all BUT one piece of modern-day evidence, which is both organelles A) contain DNA. B) contain ribosomes. C) are capable of living independently. D) are surrounded by a double membrane. The endosymbiosis theory is supported by all BUT one piece of modern-day evidence. That is both organelles are capable of living independently. Although both organelles contain RNA, DNA, and ribosomes, if extracted from eukaryotic cells, they are not capable of living independently.

C) are capable of living independently.

Scientists have studied the fossilized shells of prehistoric, single-celled marine organisms. Some of these shells were thin, which indicates that the organisms lived in very warm ocean water. Such evidence indicates that the climate during this time may have been A) moderate B) arctic. C) tropical. D) the same as it is today. If the shells were very thin and the oceans were very warm, the climate was most likely tropical. If the ocean waters were very cold, the organisms would have had thick shells to protect them from the cold.

C) tropical.

Which statement BEST explains Lamarck's theory of acquired characteristics as it relates to the neck length of giraffes? A) The DNA of the giraffe coded for longer necks in some individuals. B) The variation in giraffe neck sizes led to some being more fit and able to survive. C) Giraffes have always had long necks and this is not a characteristic that has ever changed. D) Giraffes slowly stretched their necks to reach leaves higher in the tree and over time their necks got longer. The idea of acquired characteristics would state that the giraffes slowly stretched their necks to reach leaves higher in the tree and over timetheir necks got longer. It was later determined that Lamarck's idea was untrue, and it actually based on the variations in the neck size of the giraffe's which led to more fit individuals.

D) Giraffes slowly stretched their necks to reach leaves higher in the tree and over time their necks got longer.

When the first antibiotics became available in the late 1940s and early 1950s, these antibiotics were effective against all bacterial infections. Today however, there are a multitude of antibiotic resistant bacterial infections. What conclusion can be drawn? A) Antibiotics of today are not as strong as those in the past. B) Antibiotics cause DNA mutations in bacteria, and over time, this has led to resistance. C) Over time, bacteria have turned into viruses, and antibiotics have no affect over viruses. D) Bacteria have become resistant to antibiotics over time due to evolution by means of natural selection. Bacteria have become resistant to antibiotics over time due to evolution by means of natural selection. When taking antibiotics, those bacteria that can be killed by antibiotics will die. However, due to random DNA mutations, some bacteria cells may be resistant to antibiotics. These resistant forms are the ones to survive, reproduce, and pass on their genes.

D) Bacteria have become resistant to antibiotics over time due to evolution by means of natural selection.

Some people believe that humans have always existed as the species we see today. Darwin created the theory of evolution. Which observation bolsters the theory of evolution? A) Humans have very diverse traits today. B) There appear to be missing links in the evolutionary chain. C) Life on earth has been found to date back billions of years. D) DNA found in older primate fossils resemble those of humans today. DNA found in older primate fossils resemble those of humans today. With this information, scientists can assume that there is a link between modern humans and these older fossils.

D) DNA found in older primate fossils resemble those of humans today.

Giraffes were the subject of debate in the early days of evolutionary theory. LaMarck believed in acquired characteristics, while Darwin believed in evolution by natural selection. Which is an accurate match between the author, and how he would explain the long neck of giraffes? A) LaMarck believed that giraffes were created with long necks and remained unchanged from their original design. B) Darwin believed that giraffes could stretch their necks to reach leaves and then pass this trait on to their offspring. C) LaMarck believed that over time, shorter giraffes were starved out and giraffes with longer necks survived to reproduce. D) Darwin believed that giraffes with longer necks had a higher survival rate, due to ease of feeding and reproduction, and this is the way giraffes evolved. Darwin believed that giraffes with longer necks had a higher survival rate, due to ease of feeding and reproduction, and this is the way giraffes evolved. This is consistent with evolution by natural selection, 'survival of the fittest'.

D) Darwin believed that giraffes with longer necks had a higher survival rate, due to ease of feeding and reproduction, and this is the way giraffes evolved.

Evolution is a process by which species change over the years. Various views explaining how evolution takes place have been proposed by scientists across the decades. Though most of these theories have been discarded, those of two scientists have been supported by different segments of the scientific community. Jean-Baptiste Lamarck proposed the theory of inheritance of acquired characteristics to explain the process of evolution. It suggests that an organism can change itself willfully and pass on the acquired characteristics to the next generation or its offspring. Individuals develop traits that are useful and discard others that are not according to a predefined plot. Lamarck combined these two thoughts in his theory and substantiated them by evidence. One piece of evidence cited by him was that of the giraffe's long neck. He said that giraffes stretched their necks to reach leaves on branches of high trees, and this gradually lengthened their necks over time. This acquired trait of a long neck was inherited by their offspring, and thus all giraffes now have long necks. If you were to debate Lamarck today about his theory, what core concept in biology would you rely on? A) Organisms lacking favorable traits will become extinct. B) Mutations do not result in beneficial genetic variation. C) Traits cannot be chosen willfully, but are randomly inherited from our parents. D) Environmental stresses cause organisms to change, regardless of their genetic make-up. Traits cannot be chosen willfully, but are randomly inherited from our parents. Those that inherit favorable traits to a specific situation are more likely to survive and reproduce.

C) Traits cannot be chosen willfully, but are randomly inherited from our parents.

Darwin discovered twenty different species of finches in the Galapagos islands. He hypothesized that as new islands arose, finches colonized the islands and rapidly changed into new species, depending on what food was available on each new island. The rapid formation of many new species, as in this case, is called A) gradualism. B) speciation. C) adaptive radiation. D) geographic isolation. Adaptive radiation. This is the quick formation of many new species, due to rapid adaptations to fragmented, new environments.

C) adaptive radiation.

The early ancestors of the horse (shown in the picture) were adapted to life in tropical forests. Gradually the forests disappeared and were replaced with open grasslands. Because of the gradual change in habitat, modern horses A) have five toes that allow them to walk well on soft ground. B) are herbivores instead of carnivores like their early ancestors. C) are taller with long legs and are capable of great speed to escape predators. D) have gradually grown larger, but show no major changes from the early ancestors. Because of the gradual change in habitat, modern horses are taller with long legs and are capable of great speed to escape predators. No longer living in forests, early horses lived in the open grassland and in clear sight of predators. Over time the fastest horses survived and reproduced. Modern horses have also developed teeth that allow them to graze grass instead of browsing in the forest on leaves and insects.

C) are taller with long legs and are capable of great speed to escape predators.

In older bird guides, the Audubon warbler and the myrtle warbler were classified as two separate species. For many decades, the two species lived side by side within their habitat range. In more current bird guides they are classified as eastern and western forms of the same bird species. Since the two warblers are now classified as different forms of one species, they must A) now occupy the same niche. B) be identical in appearance. C) be able to successfully interbreed. D) consistently live in the same geographic range. In order for two organisms to be considered the same species they must be able to successfully interbreed. Remember, the definition of a species is a group of organisms that can interbreed and produce fertile offspring.

C) be able to successfully interbreed.

While on the Galapagos Islands, Darwin noticed that there were a number of species of finches that he theorized descended from a common ancestor. He hypothesized that these finches became isolated on an island and adapted to fit an ecological role on that island. What about the finches led Darwin to this belief? A) feather color B) body size C) beak shape D) mating behavior The finches evolved to have different beak shapes to be able to eat the food available on the different islands.

C) beak shape

All of the scenarios are examples of evolution, with the EXCEPTION of the A) loss of hind limbs by whales. B) gradual loss of toes on the feet of horses. C) change of a caterpillar into an adult butterfly. D) change of bones in ostriches, from hollow to solid. The change of a caterpillar into an adult butterfly. Evolution takes place over an entire SPECIES over long periods of time. The change from a caterpillar to a butterfly is only one organism, and is not the result of a mutation.

C) change of a caterpillar into an adult butterfly.

In northern Canada, a population of rabbits was predominantly white in color. The allele for white color is recessive while the allele for gray color is dominant. Over the last several decades, the average annual temperature of this area has increased and the long-term deposits of ice and snow have become scarce. In this case, the frequency of a previously rare allele becomes more frequent in the population. This is an example of A) nonrandom selection. B) disruptive selection. C) directional selection. D) stabilizing selection. When the frequency of a previously scarce allele increase and a trait different from the original becomes obvious, it is referred to as directional selection. The allele for gray fur was once scarce in this population, but over time, due to environmental factors, that allele became more frequent.

C) directional selection.

The pygmy hippo, shown in the photograph, typically weighs no more than 500 pounds and is about the size of a large pig. The much larger river hippopotamus usually weighs between 3,000 and 6,000 pounds. There are no living species of hippos that are medium-sized. Which term is used to describe evolutionary selection which results in greater numbers of individuals at the extremes of the distribution and few at the center of the distribution? A) adaptive B) directional C) disruptive D) validating Disruptive. When intermediate phenotypes are not favored and extreme (in this case very small or very large) phenotypes both do well, this is called disruptive selection.

C) disruptive

All but one term describes a type of natural selection. _____________ selection is NOT a type of natural selection. A) directional B) disruptive C) distributed D) stabilizing Distributed. Distributed selection is not found among the types of natural selection.

C) distributed

How can a geological time scale BEST be reconstructed? A) comparing vestigial structures in living species B) comparing homologous structures in living species C) examining homologous structures in fossil remains D) examining the written records of scientists from past cultures examining homologous structures in fossil remains It is possible to get an idea of how things change and evolve by comparing how fossils change over time.

C) examining homologous structures in fossil remains

Some people believe that humans have always existed as the species we see today. Darwin created the theory of evolution. Which observation bolsters the theory of evolution? A) comparing vestigial structures in living species B) comparing homologous structures in living species C) examining homologous structures in fossil remains D) examining the written records of scientists from past cultures examining homologous structures in fossil remains It is possible to get an idea of how things change and evolve by comparing how fossils change over time.

C) examining homologous structures in fossil remains

Evidence from the fossil record to support punctuated equilibrium would include _______________________. A) index fossils B) transitional fossils C) fossil evidence from the Cambrian explosion D) almost fully preserved fossils that have been found in bogs, amber, and ice fossil evidence from the Cambrian explosion Punctuated equilibrium is based on the idea that we see a quick burst of change in a species and then very long periods of no change. Around 530 million years ago, a wide variety of animals burst onto the evolutionary scene in an event known as the Cambrian explosion. In perhaps as few as 10 million years, marine animals evolved most of the basic body forms that we observe in modern groups.

C) fossil evidence from the Cambrian explosion

Many species of organisms are found only on islands. Lemurs are found only on Madagascar and koalas only on Australia. Which factor contributes MOST to this situation? A) small land area B) fewer predators C) genetic isolation D) limited food variety Genetic isolation.This allows evolution to take directions independent of what is happening on the mainland. Since the animals of the island rarely migrate or have migrants, they exist as an independent ecosystem.

C) genetic isolation

Penicillin is an antibiotic that was discovered in 1928. Today, many species of bacteria have acquired resistance to penicillin. This adaptation occurred as the result of A) mutualism. B) symbiosis. C) genetic mutation. D) divergent evolution. Many bacteria have acquired the ability to produce an enzyme called penicillinase, which destroys penicillin. All enzymes are proteins. The ability to produce the new protein penicillinase came from a change in the bacterial DNA: a genetic mutation.

C) genetic mutation.

Antibiotic resistance in bacteria is the result of A) binary fission. B) nitrogen fixation C) genetic variation. D) genetic engineering. Genetic variation. Some bacteria will naturally have genetic resistance to certain antibiotics.

C) genetic variation.

Charles Darwin theorized that evolution must occur slowly, over long periods of time. This is a(n) _________ theory. A) catastrophist B) creationist C) gradualist D) punctuated gradualist Slowly, surely, this is a GRADUAL way to change.

C) gradualist

The peppered moth is often used as an example of natural selection. Most of the original moths had lighter wings, but as the soot from Industrial Revolution covered the trees, the number of darker moths increased. As the peppered moth evolved over time, its wings changed from light to dark so that it could better A) find food to eat. B) combat pollution. C) hide from predators. D) withstand its climate. The moths changed colors to blend in with their surroundings and hide from predators. Since the trees were blackened by soot, birds would easily spot light-colored moths. Dark-colored moths, on the other hand, were much harder to see.

C) hide from predators.

Despite their differences in appearance, all bony fish have common ancestors. Their fins develop from similar structures and usually have a prescribed number of bones. Because of this, the large rudder-like dorsal fin of a sailfish, the poisonous dorsal fin of a catfish, and the tiny reduced dorsal fin of a puffer fish are said to be ________ structures. A) vestigial B) analagous C) homologous D) evolutionary Homologous structures. These are traits, though different in appearance and function, that are derived from the same ancestral trait during development.

C) homologous

According to the fossil record, five ________________ took place, which lowered the variety of species found on Earth today. A) mass clonings B) microevolutions C) mass extinctions D) mass revolutions Mass extinctions. Mass extinctions resulted in the death of many species.

C) mass extinctions

In 2010 a new type of life form was found in California's Lake Mono. The microbe found has a variation in the structure of its DNA. DNA usually consists of nitrogen bases, sugars and phosphates. However, this newly-discovered microbe uses arsenic if phosphorus is not available. This fact might lead to the discovery of A) new DNA sequences in mammals. B) new DNA structures in mammals. C) possible life in non earthlike environments. D) phosphorus being unnecessary for DNA structures in mammals. The answer is possible life in non earthlike environments. The discovery opens the argument that life might exist in other areas of the universe that have a different environment than earth.

C) possible life in non earthlike environments.

Which of these statements BEST defines vestigial organs? A) vital organs that are functional in all organisms of a lineage B) vital organs that are functional only in alternate generations of a lineage C) redundant organs present in an organism, which have been functional in the organism's ancestors D) redundant organs present in an organism, which will be functional in the succeeding generations of the lineage The appendix and tail bone are seemingly redundant in humans, being reduced forms of fully functional organs in human ancestors. Vestigial organs are seemingly redundant organs present in an organism, but have been functional in the organism's ancestors.

C) redundant organs present in an organism, which have been functional in the organism's ancestors

When an existing population of organisms gives rise to two or more new species, the new species cannot effectively breed with one another. Which term is used to describe this phenomenon? A) adaptive seclusion B) species limitation C) reproductive isolation D) behavioral modification When new species are formed, they can no longer interbreed. This is called reproductive isolation.

C) reproductive isolation

Populations change naturally over time. Which mechanism is a method of artifical selection rather than natural selection? A) genetic drift B) natural selection C) selective breeding D) geographic isolation Selective breeding.Selective breeding is a type of artificial selection.

C) selective breeding

For a given species, an increased evolutionary rate would cause a decrease in A) biodiversity. B) fitness of a species. C) similarity of the individuals in the species. D) the number of new genes in the DNA of the species. Similarity of the individuals in the species. It would be expected that increased evolutionary rate would cause individuals in the species to resemble each other less.

C) similarity of the individuals in the species.

Human height tends to follow a normal distribution. For example, 80 percent of men are somewhere between 5 feet 4 inches tall and 6 feet tall, with the largest number of men standing 5 feet 8 inches tall. Smaller and taller heights are increasingly rare, as they become more extreme. For instance, less than 0.01% of the adult male population is greater than 7 feet tall or shorter than 3 feet tall. Humans have followed __________ selection with regard to the evolutionary trend for height. A) artificial B) disruptive C) stabilizing D) directional stabilizing selection. Stabilizing selection says that average traits are favored over the extremes. Height is a good example of this.

C) stabilizing

In a field of sunflowers, there are varying heights. A plant breeder is determined to breed out all of the extremely tall and extremely short plants. His goal is to create a population of sunflowers that are all of average height. In terms of natural selection, we would call this _________ selection. A) directional B) disruptive C) stabilizing D) suggestive This is an example of stabilizing selection. This happens when selective pressures select against the two extremes of a trait, in this case, tall or short plants.

C) stabilizing

In 1850 there was a large snowshoe rabbit population in Manitoba, Canada. Over the years, the winter coloration (the color of the rabbit's fur) of the surviving rabbit population changed. The graph shows the change in winter coloration of rabbits between 1850 to 2000. Based on the data, we could hypothesize that A) the winters are longer in length. B) the snowshoe rabbit has migrated to another area. C) the amount of snow cover varied over the years. D) more snowshoe rabbit predators have moved into Manitoba. Based on the data, we could hypothesize that the amount of snow cover varied over the years. Winter white coloration is an adaptation for survival in snowy areas. If more gray rabbits are surviving, then there must be less snow.

C) the amount of snow cover varied over the years.

Evolution and natural selection are necessary for A) the preservation of natural habitats. B) the short-term survival of individual organisms. C) the long-term survival of an entire species of organisms. D) successful reproduction of a species with other members of that species. The long-term survival of an entire species of organisms. Individual organisms do not have to immediately adapt to an environment. However, an accumulation of useful mutations is necessary for a species to keep pace with changes in the environment.

C) the long-term survival of an entire species of organisms.

Naturalist Jean-Baptiste Lamarck promoted the theory of "inheritance of acquired characteristics." This theory stated that changes developed over the course of the life of an organism would be transmitted to the next generation. A famous example involves a blacksmith. Working with heavy hammers, pounding iron all day, blacksmiths developed larger arms than average men. This trait, large and muscular arms, would then be passed down to the children of the blacksmith. Charles Darwin developed a competing theory based on variation and a process he called "natural selection." His theory stressed how the differences among the individuals in a population would lead to different rates of survival and reproduction. Through this process, in conjunction with what he called a "strong principle of inheritance," entire populations could adapt, and ultimately, evolve. DNA and its structure was not isolated and understood until the mid 1900s. It serves as A) the mechanism through which population evolution operates. B) an example of how the blacksmiths arms grow as large as they do. C) the mechanism by which the "strong principle of inheritance" operates. D) the mechanism by which the "inheritance of acquired characteristics" operates. The correct answer is the mechanism by which the "strong principle of inheritance" operates. DNA is the substance passed from one generation to the next, determining which traits are present.

C) the mechanism by which the "strong principle of inheritance" operates.

Naturalist Jean-Baptiste Lamarck promoted the theory of "inheritance of acquired characteristics." This theory stated that changes developed over the course of the life of an organism would be transmitted to the next generation. A famous example involves a blacksmith. Working with heavy hammers, pounding iron all day, blacksmiths developed larger arms than average men. This trait, large and muscular arms, would then be passed down to the children of the blacksmith. Charles Darwin developed a competing theory based on variation and a process he called "natural selection." His theory stressed how the differences among the individuals in a population would lead to different rates of survival and reproduction. Through this process, in conjunction with what he called a "strong principle of inheritance," entire populations could adapt, and ultimately, evolve. DNA and its structure was not isolated and understood until the mid 1900s. It serves as Naturalist Jean-Baptiste Lamarck promoted the theory of "inheritance of acquired characteristics." This theory stated that changes developed over the course of the life of an organism would be transmitted to the next generation. A famous example involves a blacksmith. Working with heavy hammers, pounding iron all day, blacksmiths developed larger arms than average men. This trait, large and muscular arms, would then be passed down to the children of the blacksmith. A) the mechanism through which population evolution operates. B) an example of how the blacksmiths arms grow as large as they do. C) the mechanism by which the "strong principle of inheritance" operates. D) the mechanism by which the "inheritance of acquired characteristics" operates. The correct answer is the mechanism by which the "strong principle of inheritance" operates. DNA is the substance passed from one generation to the next, determining which traits are present.

C) the mechanism by which the "strong principle of inheritance" operates.

Natural selection. Darwin hypothesized that there requisites for natural selection to occur and that there are definite steps to natural selection. Note the two models seen here. Both of the models illustrate an important requisite for natural selection. That is: A) sexual reproduction must occur. B) there is survival of the fittest. C) variation in the population exists. D) genetic sameness reduces the chances of natural selection. Both models show that variation in the population exists.

C) variation in the population exists.

LaMarck explained the long necks of giraffes by theorizing that they had stretched their necks to reach the leaves of trees, and they then passed on those traits to their offspring. LaMarck's theory was called 'Inheritance by Acquired Traits'. A) Darwin would've agreed completely, since they wrote the theory together. B) Darwin would've agreed and noted that in areas with short trees, giraffes have shorter necks. C) Darwin would've disagreed and noted that giraffes had long necks, solely because of DNA mutations. D) Darwin would've disagreed and argued that giraffes have long necks, because short-necked giraffes were selectively outcompeted for food, and did not survive. What would Charles Darwin have to say about LaMarck's theory? Darwin would've disagreed and argued that giraffes have long necks, because short-necked giraffes were selectively outcompeted for food, and did not survive. Darwin disagreed with LaMarck and did not know anything about DNA in the 1800's.

D) Darwin would've disagreed and argued that giraffes have long necks, because short-necked giraffes were selectively outcompeted for food, and did not survive.

A particular bird species found in North America obtains most of its food energy by catching and eating insects. A mutation arises in this bird population that increases the length of its beak. Although many mutations are harmful, this particular mutation has increased the ability of the bird to catch and eat certain insects. Which of these is the MOST LIKELY outcome of this mutation? A) The insects that are eaten by this bird are likely to become extinct. B) Sharp pointed beaks will result in the birds eating other more unusual food items. C) Other bird species will be more likely to also develop pointed beaks in order to compete. D) Individual birds with the mutation will be more likely to survive and reproduce than birds without the mutation. Individual birds with the mutation will be more likely to survive and reproduce than birds without the mutation. In other words, the mutation has enhanced the fitness of the organisms that have more pointed beaks.

D) Individual birds with the mutation will be more likely to survive and reproduce than birds without the mutation.

The Eastern grey squirrel lives mostly in oak trees that have a medium gray bark. In some cities, oak tree bark is darkening due to air pollution. This Eastern grey squirrel shows melanism, or the increase in black pigment in its fur. What is MOST LIKELY the reason for the change in fur color? A) With age; this is a very old squirrel. B) Squirrels from another region moved into the area. C) It is a way to help the grey squirrel attract a mate. D) It is a way to camouflage the squirrel in a changing habitat. The change in fur color would occur over time as a way to camouflage the squirrel in a changing habitat. This is similar to the change in moth color in England due to an increase in soot on trees during the Industrial Revolution. The darker squirrels survive as the trees darken. These are the squirrels that reproduce.

D) It is a way to camouflage the squirrel in a changing habitat.

Jimmy believed that if he exercised every day his children would be born healthy and fit. Being an avid student of biology, what comment would you make about Jimmy's belief? A) It is a true statement and Jimmy's children will be healthier. B) It is true but would be better if Jimmy's wife was included in the exercise program. C) Jimmy is partially correct; he should also eat healthy foods in order to have healthy, fit children. D) It is untrue as characteristics you acquire in your lifetime cannot be passed on to future generations. It is untrue as characteristics you acquire in your lifetime cannot be passed on to future generations.. Lamarck believed that you could acquire characteristics and then pass them on to future generations. Darwin's theory of natural selection and survival of the fittest helped prove this theory to be false.

D) It is untrue as characteristics you acquire in your lifetime cannot be passed on to future generations.

The diagram shows a type of extinct species, pterosaur, a bat, and a type of bird, a cormorant. All three organisms have wings that look and work alike, but were not evolved from a common ancestor. Which term is used to descibe body structures that look alike and serve a similar function but are not descended from a common ancestor? A) Analogous structures B) Vestigial structures C) Evolutionary features D) Homologous structures Analogous structures. Analogous structures are the result of similar needs and co-evolution of parts among organisms that are not closely related.

A) Analogous structures

The cheetah is one of the fastest animals on the planet. How would Lamarck best explain this trait? A) Cheetahs were forced to run as fast as they could to catch prey; the more they ran, the faster they became and passed this on to their offspring. B) Those cheetahs who ran fast were able to get food and survive and reproduce, passing this trait on to offspring. C) Through the survival of the fittest, slow cheetahs died. D) The environment chose fast cheetahs. Cheetahs were forced to run as fast as they could to catch prey; the more they ran, the faster they became and passed this on to their offspring. Lamarck believed in the inheritance of acquired characteristics, meaning that any behavior or trait acquired during an organism's lifetime would be passed on to offspring. Lamarck's theory is inaccurate. Darwin's theory of evolution by means of natural selection states that organisms most suited to the environment survive, reproduce, and pass these advantageous traits on to offspring. Those not well adapted die.

A) Cheetahs were forced to run as fast as they could to catch prey; the more they ran, the faster they became and passed this on to their offspring.

The cheetah is one of the fastest animals on the planet. How would Lamarck best explain this trait? A) Cheetahs were forced to run as fast as they could to catch prey; the more they ran, the faster they became and passed this on to their offspring. B) Those cheetahs who ran fast were able to get food and survive and reproduce, passing this trait on to offspring. C) Through the survival of the fittest, slow cheetahs died. D) The environment chose fast cheetahs. Cheetahs were forced to run as fast as they could to catch prey; the more they ran, the faster they became and passed this on to their offspring. Lamarck believed in the inheritance of acquired characteristics, meaning that any behavior or trait acquired during an organism's lifetime would be passed on to offspring. Lamarck's theory is inaccurate. Darwin's theory of evolution by means of natural selection states that organisms most suited to the environment survive, reproduce, and pass these advantageous traits on to offspring. Those not well adapted die.

A) Cheetahs were forced to run as fast as they could to catch prey; the more they ran, the faster they became and passed this on to their offspring.

The graph shows the results of a famous biological experiment. In the experiment, Kettlewell believed that the peppered moth demonstrated how environmental pressures influence evolution. He studied two areas. Birmingham was a rural wood, with natural conditions. Dorset was an urban, industrial area. The moths use tree trunks to camouflage themselves against birds, which are their major predators. Natural gene variations produce a light form of the peppered moth, and a dark form, meaning that they are not equally visible. All BUT ONE statement is supported by Kettlewell's data. That is A) Dark moths had a survival disadvantage in industrial Dorset. B) Light moths had a survival advantage in forested Birmingham. C) Light moths had a survival disadvantage in industrial Dorset. D) Dark moths had a survival disadvantage in forested Birmingham. Dark moths had a survival disadvantage in industrial Dorset. After the introduction of industry, the dark moth population remained approximately the same in Dorset to Birmingham. However, the light moths in the rural area still had a much larger population.

A) Dark moths had a survival disadvantage in industrial Dorset.

Lamarck's theory of evolution appeared in his book Philosophie zoologique, which he wrote in 1809. His evolutionary theory included the following principles: • Environmental changes generate new needs • These needs determine the use or disuse of some organs • Such organs are develop or diminished respectively • The acquired characters become hereditary Which one of these examples did Lamarck use to support his theory, which eventually was proven incorrect? A) Giraffes evolved their long necks by stretching. B) Wading birds evolved their long legs by stretching them to remain dry. C) Children of professional weight lifters are born with normal-sized muscles. D) Chameleons can change their skin color to protect themselves from predators. According to Lamarck's theory, a given giraffe could, over a lifetime of straining to reach high branches, develop an elongated neck and giraffes evolved their long necks by stretching. A major downfall of his theory was that he could not explain how this might happen, though he discussed a "natural tendency toward perfection." Another example Lamarck used was the toes of water birds. He proposed that from years of straining their toes to swim through water, these birds gained elongated, webbed toes for better swimming.

A) Giraffes evolved their long necks by stretching.

All of these factors influenced Darwin in his writing of the theory of evolution by natural selection EXCEPT one. Which factor did not influence Darwin's theory? A) He was strongly against creationism and set out to disprove it. B) He noticed similarities between animals and plants from different places in the world. C) Another author, Alfred Wallace, was competing against him, largely writing the same theory. D) He recognized similarities in Malthus's theory of food limitations and with the rules of nature. He was strongly against creationism and set out to disprove it. Darwin did not set out to make his findings fit a set of rules.

A) He was strongly against creationism and set out to disprove it.

Place the developments in evolutionary history in the proper time frame. I) Charles Darwin writes 'On the Origin of Species'. II) LaMarck writes about evolution through acquired traits, using a giraffe as his model. III) DNA sequencing is developed, allowing the comparison of the genes of different organisms. IV) Malthus, an economist, writes about the inevitability that people will exhaust a food supply by reproducing too often. A) IV, II, I, III B) I, II, IV, III C) II, I, IV, III D) II, I, III, IV IV, II, I, III Malthus (1798) inspired Darwin (1859) through his ideas, but in between these two events, LaMarck penned his own ideas (1809). DNA sequencing did not come along until the end of the 20th century.

A) IV, II, I, III

Bed bugs might sound like an old-fashioned problem, but now they are back with a vengeance. Fifty years ago, the blood-sucking pests were nearly eradicated in the United States thanks in part to the use of pesticides like DDT. Today, they are creeping over sheets and tormenting sleepers across the country. New York was recently declared America's most bed-bug-infested city in America. In the past, we countered the bed bugs by using pesticides called pyrethrins and pyrethroids. These compounds work by attacking the nervous system. Insects have channels in the membranes of their nerve cells that can be opened to allow sodium into the cells, triggering a nerve impulse. Pyrethrins and pyrethroids alter the nervous system by binding to the sodium channels, locking them in the open position. This allows sodium to pour into the cell continuously, causing the nerve to fire repeatedly and eventually leading to paralysis. Todays bed bugs seem to be more resistant to the chemicals. Biologists have determined that mutations are responsible for this resistance. Mutations changing just two of the 2000 amino acids that make up part of the sodium channels would be enough to make an insect 250 times more resistant to a commonly used pyrethroid. These mutations may change the channel so that the insecticide can no longer bind to it effectively. Explain how a mutation causing resistance to pyrethrins and pyrethroids would spread through a population of bed bugs that are being treated with the pesticide. A) In a population of bed bugs, variation exists. Some variation provides resistance to the pesticides. Those bed bugs survive to reproduce, passing the resistance on to offspring. B) Mutations happen randomly to change the gene pool of a population. The mutations are favored when a population of organisms winds up in an environment in which the mutations happen to be useful. C) When a population of insects, like bed bugs, is subjected to pesticides, some of the bed bugs alter their genetic make-up and they are able to survive. They then pass the new genes on to offspring. D) In any population of organisms, sexual reproduction provides for variation in the gene pool. Such variation allows some insects to be resistant to pesticides. When sexual reproduction occurs again, the resistance is passed to offspring. In a population of bed bugs, variation exists. Some variation provides resistance to the pesticides. Those bed bugs survive to reproduce, passing the resistance on to offspring. The steps to natural selections include: variation, selection, and inheritance. One other answer is a true statement; it just does not answer the question.

A) In a population of bed bugs, variation exists. Some variation provides resistance to the pesticides. Those bed bugs survive to reproduce, passing the resistance on to offspring.

The contraction of auricular muscles around the ear produces a range of motions in the ears of domesticated animals as well as the macaque monkey and most other monkeys. Thanks to these muscular motions, the ears act as antennae and can be used to sense danger and locate prey. Humans and other primates such as the orangutan and chimpanzee have ear muscles that are minimally developed and non-functional. How are these vestigial ear muscles an example of natural selection? A) In most primates the inability to move the ear has been replaced by the ability to turn the head on a horizontal plane as well as having peripheral vision. B) Most primates are not victims of predators and they are not predators themselves so they do not need this trait. C) In most primates the inability to move the ear has been replaced by the ability to stand upright on two legs. D) A muscle attached to the ear that cannot move the ear has no function. In most primates the inability to move the ear has been replaced by the ability to turn the head on a horizontal plane as well as having peripheral vision. The function of the movable ear has been replaced by the function of other parts of the muscular and sensory systems.

A) In most primates the inability to move the ear has been replaced by the ability to turn the head on a horizontal plane as well as having peripheral vision.

Peppered moths come in two colors, black and white. What did Kettlewell show, with regard to peppered moth populations and tree coloring? (Recall that England at the time was heated mainly by coal in urban areas.) A) In smoggy areas, dark moths have a higher survival rate than white moths. B) White moths stand out in rural areas, and quickly disappear from those areas. C) The black moth and white moth forms were actually two different species of moths. D) Environmental conditions do not affect physical features of a species over a short time period. In smoggy areas, dark moths have a higher survival rate than white moths. Kettlewell showed that the environment puts selection pressures on physical traits. In smoggy areas, dark moths hide from birds more effectively on tree trunks. In rural areas, trunks remain light and white moths do better.

A) In smoggy areas, dark moths have a higher survival rate than white moths.

Darwin observed how farmers and breeders produced many kinds of farm animals and plants. These plants and animals had traits that were desired by the farmers and breeders. He also noticed how the study of similar body structures and vestigial organs could add to the evidence of evolution. After performing several breeding experiments, he came to certain conclusions and formulated some theories. His theory of evolution and natural selection is the most accepted one. What is the reason behind the acceptance of Darwin's theory? A) It is supported by practical evidence and examples. B) It is supported by its harmonizing with other views. C) It is based on the ideas of earlier hypothesis and laws. D) It is based on the practical example of Lamarck's theory Darwin's theory It is supported by practical evidence and examples. Darwin explained each aspect of the theory with sufficient practical examples and is the most accepted theory of evolution.

A) It is supported by practical evidence and examples.

______________ was demonstrated in the darkening of the population of the peppered moth in Europe over a relatively short period of time. A) Natural selection B) Natural integration C) Kettlewell adaptation D) Industrial modification In the case of the peppered moth, industrial pollution was the selective pressure that led to the change in the population. The process of natural selection caused change over a short period of time.

A) Natural selection

Based on the data given, what is the BEST conclusion to be drawn? A) Over time, due to evolution by means of natural selection, resistant weeds survived, reproduced, and passed on their herbicide resistant genes. B) Over time, the amount of herbicide resistant plants increased due to an increase in farming. C) More weeds are killed today by herbicides than any other time in history. D) Herbicide is a natural mutagen, causing weeds to turn into super weeds. Over time, due to evolution by means of natural selection, resistant weeds survived, reproduced, and passed on their herbicide resistant genes. Through random mutations in DNA, some weeds became resistant to the chemicals. These resistant forms are the ones to survive, reproduce, and pass on their genes.

A) Over time, due to evolution by means of natural selection, resistant weeds survived, reproduced, and passed on their herbicide resistant genes.

During his groundbreaking experimental work with chemical evolution, Stanley Miller stated: The essential difference between life and non-life is replication. Miller also hypothesized that small inorganic molecules gave rise to larger organic molecules or polymers. Based on Miller's experiments, chemical evolution theory proposes that the first genetic material was probably A) RNA. B) DNA. C) amino acids. D) simple proteins Chemical evolution posits that RNA was the original genetic material. Short RNA polymers formed simple genes, that could self-replicate. The RNA acted as a template from which polypeptides formed, polypeptides which could also function as enzymes.

A) RNA.

Charles Darwin is best know for developing his theory of evolution based on his observation of what characteristic? A) The beaks of finches B) The scales of snakes C) The necks of giraffes D) The trunks of elephants Darwin is best known for studying the beaks of finches on the Galapagos Islands. He noticed different sizes and shaped beaks based on where the finch lived and what it ate

A) The beaks of finches

The arm or forelimb of humans, horses, goats, and mice all exhibit the same three bone structures: humerus, ulna, and radius. Which statement BEST explains this common skeletal structure? A) The limb bones are similar across these species because they share a common ancestor. B) The limb bones are the same across these species because all of them move in a similar way. C) The limbs are similar because of the recurring patterns of genetic mutation that are common in the Animal Kingdom. D) The limbs are structurally similar due to convergent evolution--different organisms evolving to become structurally similar. The limb bones are similar across these species because they share a common ancestor. These forelimbs are considered homologous structures.

A) The limb bones are similar across these species because they share a common ancestor.

A population of lizards were living in an area that began to experience a great amount of mountain building. As the mountains formed some lizards were on one side of the mountains and the rest were on the other side of the mountains. Over a period of many years the lizards were no longer able to breed, or had become different species. Why did this happen? A) The lizards on one side of the mountain were exposed to different conditions and therefore different characteristics were selected. B) The lizards on one side of the mountain were exposed to different conditions and therefore the same characteristics were selected. C) The lizards on one side of the mountain were exposed to identical conditions and therefore different characteristics were selected. D) The lizards on one side of the mountain were exposed to identical conditions and therefore the same characteristics were selected. The lizards on one side of the mountain were exposed to different conditions and therefore different characteristics were selected. As these different characteristics were selected the two groups evolved independently into different species.

A) The lizards on one side of the mountain were exposed to different conditions and therefore different characteristics were selected.

The graph shows the results of a famous biological experiment. In the experiment, Kettlewell believed that the peppered moth demonstrated how environmental pressures influence evolution. He studied two areas. Birmingham was a rural wooded area; Dorset was an urban area. The moths land on tree trunks and are camouflaged against birds, their major predators. Natural genetic variations produce a light form and a dark form of the peppered moth. If Kettlewell had gone to an area comprised of equal parts urban and rural space, what would his prediction have been about the ratio of dark moths to light moths? A) They would be found in near equal amounts. B) It is impossible to predict using only the given data. C) The darker moths would be much higher in number than the lighter moths. D) The lighter moths would be much higher in number than the darker moths. They would be found in near equal amounts. This would represent a balance between the results at Dorsett and Birmingham, reflecting the pressure exerted by the environment on selection.

A) They would be found in near equal amounts.

Pests have always been a nuisance for farmers. The use of pesticides dramatically improved the success of crops; however, it has been found that some insects are no longer harmed by traditional pesticides. How would Charles Darwin, the man behind the theory of evolution by means of natural selection, explain this phenomenon. A) Through random mutations in DNA, some pests developed a resistance to the pesticide. B) The chemicals used in pesticides today are not strong enough to kill unwanted pests. C) The pesticides used in the past caused unwanted mutations in pests causing them to mutate into superbugs. D) Through repeated exposure to the pesticides, the pests simply got use to to the chemicals and built up a resistance. Through random mutations in DNA, some pests developed a resistance to the pesticide. Through random mutations in DNA, some pests became resistant to the chemicals. These resistant forms are the ones to survive, reproduce, and pass on their genes.

A) Through random mutations in DNA, some pests developed a resistance to the pesticide.

The carbon-14 isotope is important because it allows scientists to determine the ___________ of an organic sample. A) age B) density C) evolution D) mass Carbon-14 is the radioactive isotope that is used to help determine the age of an organic sample. The older the sample, the more the sample will have decayed, and the less radioactive it will be.

A) age

A scientist is interested in studying the growth pattern of dinosaur embryos. Which of these organisms is MOST likely to have an embryonic development pattern similar to an extinct dinosaur? A) alligator B) bat C) horse D) mouse A reptile like an alligator is most likely to be similar in development to an extinct dinosaur. The other choices are all mammals that are unlikely to have an embryological development like that of a dinosaur.

A) alligator

According to evolutionary theory and the fossil record, which type of plant appeared just after this gymnosperm? A) angiosperms B) bryophytes C) pterophytes D) sporophytes Angiosperms or flowering plants appeared on Earth after the gymnosperms.

A) angiosperms

In evolutionary history, the first animals to successfully invade land from the sea were ___________________, an animal with a hard outer skeleton and jointed limbs. A) arthropods B) dinosaurs C) protists D) reptiles Arthropods. Arthropods,like insects and crabs, were (and still are) the most successful land dwelling animals. They were first to establish themselves on "dry" land.

A) arthropods

The process of evolution involves changes in the genetic makeup of a population over a period of time. Sexual reproduction enhances variability among offspring. The random alteration of DNA from parent to offspring, called mutations, also produces variable characteristics in offspring. Some mutations can be helpful, while others can be harmful and hinder survival. In this experiment, students mimicked random mutations and the ability to collect and eat food. Each experimental group was timed for both collection and eating of the food, and data was collected to determine if the mutations were helpful or harmful when trying to collect and eat food. Of all the mutations, which one would MOST LIKELY contribute to a rapid rate of extinction? A) blindness B) paddle hands C) no peripheral vision D) fused hands, no range of motion Of all the mutations, blindness would most likely lead to extinction. These organisms cannot see. They cannot find food and they cannot protect themselves from predators.

A) blindness

It is estimated that humans branched off of their common hominid ancestors about 5-7 million years ago along with which of these organisms? A) chimpanzees B) giraffes C) horses D) platypus It is believed that humans and chimpanzees branched off of the other hominids about 5-7 million years ago. Of course, human development continued from there with the continued evolution of these early ancestors.

A) chimpanzees

Both the arctic fox and snowshoe rabbit have made species adaptations over time that enable them to survive. For example, both creatures have fur that turns white in winter and fur on the pads of their feet. These are examples of adaptations to A) climate. B) geographic isolation. C) specific food sources. D) interspecies competition. Both the arctic fox and snowshoe hare have physically changed over time in ways that related species have not. These changes are adaptations to climate, specifically to cold and snow.

A) climate.

What geological theory explains how llamas and camels, close relatives, might be found on different sides of the world? A) continental drift B) natural selection C) radiocarbon dating D) endosymbiont theory Continental drift. The idea of continental drift, that all continents were once connected as a large continent known as Pangea, explains how a common ancestor might have migrated in two directions and been separated.

A) continental drift

Green and brown algae share many common features. Both have pigments for trapping sunlight and use photosynthesis for energy. Both store their food as sugars. Both have cell walls and plant-like bodies. However, their DNA suggests that they are not even remotely related to one another. Green algae and brown algae show __________________ evolution, since they look similar, but are not close relatives. A) convergent B) divergent C) homologous D) vestigial Convergent. In convergent evolution, unrelated organisms develop similar features in response to similar pressures from the environment.

A) convergent

Imagine a field of flowers; a field of flowers that are pollinated by basically three different pollinators. One pollinator, bees, attracted to short plants. Another, butterflies, prefer plants of medium height and a third pollinator, birds, visits only the tallest plants. Pesticide spraying kills many insect pests in the field of flowers but also wipes out the butterfly and bee populations. Over time, only birds pollinate tall flowers and eventually the flower gene pool favors taller flowers. This is also an example of ____________ selection. A) directional B) disruptive C) environmental D) stabilizing This is an example of directional selection. In directional selection, selection pressures favor an extreme, inthis case, tall. Very short flowers could have been the opposite direction for change.

A) directional

Imagine this field of flowers. Environmental conditions change. The climate becomes colder and the winds become fierce. Such a climate favors plants that grow close to the ground, have needles, and have bright flowers. In this field of flowers, only the shortest plants survive. Over time, the population consists of very short, low growing plants. This is also an example of ____________ selection. A) directional B) disruptive C) environmental D) stabilizing This is an example of directional selection. In directional selection, selection pressures favor an extreme, in this case, short plants.tall.

A) directional

According to the theory of _____________, mitochondria in cells today are the descendents of aerobic prokaryotes that used oxygen to generate energy. A) endosymbiosis B) ingestion C) mutualism D) parasitism Endosymbiosis. According to endosymbiosis, mitochondria were once free-living organisms that became a permanent part of host cells.

A) endosymbiosis

Charles Darwin studied finches on the Galapagos Islands. While the finches on all the islands came from the same ancestors, the distance between the islands was too great to allow finches from different islands to interbreed. Over time, the size of the finches on the different islands remained the same, but the shape and size of their beaks changed, as shown here. This adaptation helped the finches find food on their particular island. The change in the size and shape of the finches' beaks was MOST LIKELY caused by A) geographic isolation B) a change in climate. C) endangerment of the species. D) a decrease in the mutation rate. Because each finch was confined to a single island, each adapted differently to the conditions on its particular island. One of these conditions was food—some finches ate from cacti growing on the island while others ate seeds. The cause of these changes was the geographic isolation of the finches.

A) geographic isolation

The term fish is used for any any swimming vertebrate with fins. It includes a diverse group of animals, divided into four taxonomic classes, Agnatha, Chondrichthyes, Osteichthyes, and Placoderma. Taxonomists first divided all "fish" into two classes, Agnatha and Placoderma. The Placoderma are considered ancestors of all other fish. What fossil evidence helped taxonomists separate all "fish" into these two branches for classification? A) jaw or jawless B) ray fins or lobed fins C) skeleton or no skeleton D) cartilage versus bony skeleton The class Agnatha, represented by hagfish and lampreys, are structurally different from fossil remains of the Placoderma. Agnatha are jawless fish and in addition, lampreys do not have paired fins. The fossil Placoderma, with jaws and paired fins, are thought to give rise to the other two classes of fish.

A) jaw or jawless

Which characteristic is the most primitive and least evolved trait, with regard to plants? A) lack of vascular tissue B) seeds enclosed with cones C) use of spores instead of seeds D) separate sexes on different plants lack of vascular tissue. Mosses and liverworts, non-vascular plants, are the least evolved plants, and must remain near water, because they cannot 'wick' water up their stems.

A) lack of vascular tissue

Suppose a species of nonpoisonous snake is dark-colored, and a species of poisonous snake is brightly colored. Predators recognize the bright colors of the poisonous snake and stay away from it, but they frequently feast on the nonpoisonous snake. Some nonpoisonous snakes, like the king snake look a lot like a poisonous variety. In this case, the king snake looks like the deadly coral snake. The king snake is not attacked by predators and survives. This adaptation which allows for natural selection is called A) mimicry. B) evolution. C) camouflage. D) variation. This adaptation that allows for natural selection is called mimicry. Predators avoid the king snake, even though it is nonpoisonous, and it survives to reproduce.

A) mimicry.

Suppose a species of nonpoisonous snake is dark-colored, and a species of poisonous snake is brightly colored. Predators recognize the bright colors of the poisonous snake and stay away from it, but they frequently feast on the nonpoisonous snake. Some nonpoisonous snakes, like the king snake look a lot like a poisonous variety. In this case, the king snake looks like the deadly coral snake. The king snake is not attacked by predators and survives. A) mimicry. B) evolution. C) camouflage. D) variation. This adaptation that allows for natural selection is called mimicry. Predators avoid the king snake, even though it is nonpoisonous, and it survives to reproduce.

A) mimicry.

Which of these pairs of body structures BEST illustrates a homologous relationship? A) the leg of a horse and the leg of a dog B) the wing of a bat and the wing of a bird C) the fin of a dolphin and the fin of a shark D) the beak of a bird and the beak of a turtle The leg of a horse and the leg of a dog illustrates a homologous relationship. Homologous structures are structures that may look different but develop from the same embryological tissues and indicate a close evolutionary relationship.

A) the leg of a horse and the leg of a dog

The table shows the amino acid present at ten positions in the myoglobin protein in five different organisms. Based on this evidence, a researcher could conclude that A) the two closest relatives are lemurs and gibbons. B) cows are more closely related to gibbons than they are to pigs. C) the myoglobin of pigs and cows is more similar than the myoglobin of lemurs and gibbons. D) no amino acids at any position of the myoglobin protein remained unchanged across all animals. The two closest relatives are lemurs and gibbons. There is only one amino acid difference between these two organisms, at the 7th position (Trp or Phe).

A) the two closest relatives are lemurs and gibbons.

The information contained in the table could be used _______________________. A) to establish the degree of relatedness among these organisms B) to determine which organisms underwent convergent evolution C) to show how protein shape determines function D) in comparative embryology studies to establish the degree of relatedness among these organisms The more similar the DNA, the greater the degree of relatedness, or the more recent in time the two organisms diverged from a common ancestor. If there is a great difference in DNA sequencing, this suggests that the organisms shared a common ancestor a long time ago.

A) to establish the degree of relatedness among these organisms

Punctuated equilibrium verses gradualism have long been contested as ways in which species evolve. Choose the BEST evidence for gradualism. A) transitional fossils B) fossil evidence of the Cambrian explosion C) evolution by means of acquired characteristics D) rapid molecular evolution within phylogenetic trees of closely related organisms Transitional fossils Gradualism is the idea that large changes are actually the culmination of very small changes that build up over time. Transitional fossils are fossils in the record that show structural adaptations of species as they transform into new species slowly over time. Punctuated equilibrium is based on the idea that we see a quick burst of change in a species and then very long periods of no change.

A) transitional fossils

Whales are thought to have evolved from land animals similar to large otters. As evidence of this, whales have useless leg bones (structure C) that float inside their bodies. These leg bones are ___________ structures. A) vestigial B) homologous C) analagous D) evolutionary Vestigial. Vestigial structures are useless structural leftovers, such as wisdom teeth, appendixes, and tailbones in humans.

A) vestigial

Which situation is a good illustration of a biologically resistant species? A) A mule, despite being the product of two different species (a horse and a donkey). B) A staph bacteria in a hospital that is not killed by penicillin or several other antibiotics. C) An alligator. Alligators still survive, despite being dated by fossils to the time of dinosaurs. D) A species of African cichlid fish, which is thought to have rapidly evolved, along with 500 other similar species. A staph bacteria in a hospital that is not killed by penicillin or several other antibiotics. Biological resistance is a phenomenon that is caused by artificial selection, as resistant bacteria survive and the species evolves resistance.

B) A staph bacteria in a hospital that is not killed by penicillin or several other antibiotics.

The human body contains structures that are needed for survival, or in the case of vestigial structures, were needed for survival. Wisdom teeth, seen here, are vestigial third molars. Human ancestors had larger jaws with more teeth. Over thousands of years, man no longer needed the third molar, and they became the source of dental problems rather than an aid in survival. How does this vestigial structure support the theory of natural selection? A) The six of man's cranial cavity evolved. With increased cranial cavity size, the size of man's brain also grew. This resulted in a smaller jaw and no room for the third molars. B) Agriculture and the use of fire changed what and how man ate and the need for these teeth diminished over time. Jaw size and shaped evolved and there was insufficient room for the third molars. C) The climate on Earth changed from very cold to tropical. The tropical climate on Earth lead to a change in the diet of humans and that lead to the need for sharp, pointed teeth rather than molars. D) The third molars erupt in the mouth later in the life of a human. As the life span of human ancestors increased, the need for these third molars decreased. Man was able to live a longer life without the molars. Agriculture and the use of fire changed what and how man ate and the need for these teeth diminished over time. Jaw size and shaped evolved and there was insufficient room for the third molars. The skulls of human ancestors had larger jaws with more teeth, which possibly helped to chew foliage and other raw plant parts. After the advent of agriculture 10 000 years ago as well as the use of fire to cook foods, softer human diets became the norm, including carbohydrate and high energy foods.

B) Agriculture and the use of fire changed what and how man ate and the need for these teeth diminished over time. Jaw size and shaped evolved and there was insufficient room for the third molars.

The amino acids for beta hemoglobin found in five animal species were compared to the amino acids found in human (Homo sapiens) beta hemoglobin. The number of sequence differences was recorded. Based on the molecular data, what inference could you make about the anatomy of these species compared to human anatomy? A) Anatomically, lemurs are most like humans. B) Anatomically, gorillas are most like humans. C) Anatomically, none of the species are similar to humans. D) Anatomically, only the lemur differs from humans in any way. Anatomically, gorillas are most like humans. There is only one difference in the amino acid sequences between humans and gorillas. Therefore, they would be considered most closely related and its anatomy would most resemble that of humans. Least related and least similar anatomically would be the lemur.

B) Anatomically, gorillas are most like humans.

Why are many bacterial infections more difficult to treat now than they were fifty years ago? A) Because there are more types of bacteria now. B) Because bacteria have evolved resistance to antibiotics. C) Because bacteria reproduce at greater rates than in the past, since there are more people on earth. D) Because treatment of virus infections consumes many antibiotics that were formerly used only for bacteria. Because bacteria have evolved resistance to antibiotics. Antibiotics have eliminated weaker bacteria and allowed bacteria with natural resistance to survive in their place.

B) Because bacteria have evolved resistance to antibiotics.

____________________ helps explain why there are a large number of marsupial mammal species in Australia and South America, two continents that were once connected. A) Ozone production B) Continental drift C) The fifth mass extinction D) The first mass extinction Continental drift is the movement of the major land masses over geologic time and helps explain why there are marsupial mammals on two separate continents today.

B) Continental drift

The albino cavefish lives deep inside of caves where very little light ever reaches. This species is blind, and its skin actually has grown over where its eyes should be. Knowing that they developed from ancestors that could see, which of the these would best help explain why the albino cavefish is now blind? A) Botany B) Evolution C) Microbiology D) Mycology Evolution is the study of organisms change over time, and it is the best answer to this question.

B) Evolution

About 96% of the information in human DNA is found in gorilla DNA. This evidence supports which statement? A) Humans evolved from gorillas. B) Gorillas and humans diverged from a common ancestor. C) As gorillas evolve, they will become more similar to humans. D) Gorillas and humans are too different for meaningful genetic comparisons. Gorillas and humans diverged from a common ancestor. Similarities in DNA, according to evolutionary theory, point to a common ancestor.

B) Gorillas and humans diverged from a common ancestor.

The graph above was made by a biologist working in the Galapagos islands. The biologist examined the stomach contents of the ground finch, the leaf finch, and the cactus finch, to determine what foods they usually ate. The graph shows the average number of seeds of the 4 most common plant species found in the stomach of each type of bird. Based on the graph, which statement is correct about the relationship between the ground finch and the cactus finch? A) Neither species of finch has diet similarities to the leaf finch. B) Ground finches and cactus finches mostly occupy different feeding niches. C) Ground finches and cactus finches probably compete strongly for cactus seeds. D) Daisy seeds make up a large portion of the diet of both types of finch, so they both occupy the same niche. Ground finches and cactus finches mostly occupy different feeding niches. Ground finches mostly eat grass & daisy seeds, while cactus finches mostly eat agave and cactus seeds. There is not much of a niche overlap.

B) Ground finches and cactus finches mostly occupy different feeding niches.

Geologists discovered fossil evidence of mesohippus, an ancestor of the modern horse. Mesohippus lived in North America about 40 million years ago. Mesohippus was about two feet tall, ran on hooves with three toes, and had large, grinding teeth. What statement is BEST supported by the fossil evidence? A) Ancient horses were once carnivores. B) Horses have evolved over the last 40 million years. C) Horses migrated from South America into North America. D) Modern-day horses share a common ancestor with all mammals. Horses have evolved over the last 40 million years. Horses have changed over the last 40 million years; to change means to evolve. Horses are now much larger.

B) Horses have evolved over the last 40 million years.

Which statement is NOT a component of Darwin's original theory of evolution by natural selection? A) There is variation in all offspring. B) Humans and apes evolved separately from monkeys. C) All species over-reproduce to ensure their survival. D) Organisms with the most favorable traits tend to survive and reproduce at higher rates. Humans and apes evolved separately from monkeys. Darwin's theory of evolution by natural selection described the mechanisms of how evolution worked and did not describe any specific circumstances.

B) Humans and apes evolved separately from monkeys.

Darwin hypothesized that there are definite steps to natural selection. Consider the model here. Use the Roman numerals (I - III) to guide you through the steps. Which is an accurate description of Darwin's hypothesized theory of natural selection? A) Sexual reproduction of bacteria cause variation. Some bacteria survive and some do not. Over time all of the bacteria should become extinct. B) In any population, variation exists. Some bacteria are resistant to antibiotics. Most bacteria die, but the bacteria that are resistant survive and reproduce. C) In a population of bacteria that are exposed to antibiotics, some bacteria change their genetic make-up and survive. The new genetic make-up is passed on to offspring. D) There is a change in the environment: an antibiotic is added. Some of the bacteria are capable of changing to the new environment. They survive and reproduce, passing along their favorable traits. In any population, variation exists. Some bacteria are resistant to antibiotics. Most bacteria die, but the bacteria that are resistant survive and reproduce. Most often, bacteria reproduce quickly using asexual reproduction. A mutation may cause the drug-resistance.

B) In any population, variation exists. Some bacteria are resistant to antibiotics. Most bacteria die, but the bacteria that are resistant survive and reproduce.

Which of these scientists is best known for his idea that characteristics an individual gains in its lifetime could be passed on to future generations, eventually leading to the creation of new species? A) Darwin B) Lamarck C) Linnaeus D) Mendel Lamarck believed in acquired characteristics. He believed that characteristics an individual gains in its lifetime can the be passed on to future generations. This was later proven to be untrue.

B) Lamarck

European rabbits were introduced to Australia in 1859. The rabbits reproduced rapidly in their new environment, displaced other animals and overgrazed vegetation. In an attempt to reduce the rabbit population, a deadly virus was introduced in 1951. When the virus was first introduced, the rabbits died in large numbers, but the death rate decreased over time. What statement best explains the decrease in the rabbit death rate? A) The virus had a short life span and died out with the rabbits. B) Natural selection favored rabbits that were resistant to the virus. C) The rabbits died of natural causes and the introduced virus did not work. D) Young rabbits exhibited a learned behavior and began to avoid being infected by the virus. Natural selection favored rabbits that were resistant to the virus. Natural selection is considered a mechanism of evolution. Individuals that are better adapted to their environment are more likely to survive and reproduce than other less fit members of the same species. In essence, nature "selects" those individuals with beneficial traits.

B) Natural selection favored rabbits that were resistant to the virus.

While visiting the Galapagos Islands in 1835, Charles Darwin collected over thirteen different species of a type of bird called a finch. He later observed that the birds were similar in many ways but often differed in the size and shape of their beaks. Which statement BEST summarizes Darwin's explanantion for the different beaks he observed in these finch species? A) The beaks changed so they could eat different foods. B) The beaks of each finch species were the result of natural selection. C) The size and shape of the beaks differed because of the effects of artificial selection. D) The size and shape of the beaks differed because of different climates found on the islands. The beaks of each finch species were the result of natural selection. Darwin believed that the shape and size of the beak were best suited for the environment in which the bird lived.

B) The beaks of each finch species were the result of natural selection.

Charles Darwin is well known for developing the theory of evolution based on his observations of the finches found on the Galapagos Islands. Which of these would be an example of how someone would explain why the finches had different beak sizes PRIOR to the ideas developed by Darwin? A) The differences in their DNA led to different beak sizes. B) The finches have always had different beak sizes and that has never changed throughout time. C) The finches continue to slowly change today based on the slight differences found within the population. D) The variations within the finch population led to certain individuals being better fit to survive in different conditions. Prior to Darwin, one might have believed that the finches have always had different beak sizes and that has never changed throughout time. It was believed that all organisms appeared on earth at the same time and have never changed,. Darwin helped pave the way to showing that organisms do change over time, and it is due to the slight changes found within the population.

B) The finches have always had different beak sizes and that has never changed throughout time.

The snowshoe rabbit has white fur in winter and dark fur in summer. What is the main survival advantage of this fur color change to the rabbit? A) The light fur keeps the rabbit from getting sunburned in summer. B) The fur color is an adaptive form of camouflage to avoid predators. C) The dark fur absorbs more sunlight so the rabbit is warmer in winter. D) The white fur is more valuable to fur trappers, so the animal will be trapped and better fed in winter. The fur color is an adaptive form of camouflage to avoid predators. The rabbit is dark during summer to blend in with foliage, and light during winter, to blend in with snow.

B) The fur color is an adaptive form of camouflage to avoid predators.

During the rainy months in Africa, temporary pools of water form. One fish species, the snakehead fish, is able to walk, using pectoral fins, from pool to pool. Other fish in the same area cannot travel from pool to pool. During the dry season, the pools gradually disappear. If the climate in Africa remains the same as described, what would you MOST LIKELY expect to see after many years? A) The snakehead fish will develop legs and feet. B) The snakehead fish will replace the other fish species. C) The snakehead fish will walk to another part of Africa. D) The non-walking fish will learn to use their fins to walk. If the climate remains the same, we would expect to see that the snakehead fish will replace the other fish species after many years. This is an example of natural selection. The fish that can walk from pool to pool to survive, can more easily reproduce. The fish that cannot walk from pool to pool as they dry up, do not survive to reproduce.

B) The snakehead fish will replace the other fish species.

The dots represent a bacterial infection. Sal was very sick with this bacterial infection. The infection was treated with antibiotics. Sal seemed to get well, but in a few weeks, she was sick again. How can this be explained using natural selection? A) The antibiotics were ineffective to this strain of bacteria. B) The stronger, more resistant bacteria survived the antibiotics and reproduced. C) The antibiotics did not kill the bacteria; it only forced them to be dormant. D) Antibiotics will only kill a portion of the bacteria, no matter how much medicine Sal takes. The stronger, resistant bacteria was able to survive the antibiotics and reproduce. As seen in the diagram, the orange-red bacteria survived and were then able to reproduce to make more of that type of bacteria. Another way to describe this is survival of the fittest.

B) The stronger, more resistant bacteria survived the antibiotics and reproduced.

A population of green iguanas lived on a tropical island. Originally, most of the iguanas had feet without webbing between their toes and a long round tail. A few iguanas had webbed feet and a short, flat tail. As the years passed, the island became smaller and smaller because of flooding. Even the land areas were dotted with ponds and pools. The iguanas had a hard time finding the food they normally ate. To survive, the iguanas had to swim from island to island to find food. How would you expect the iguanas to look many years after the island flooded and food became harder to find? A) The iguanas will look the same but there will be less of them. B) There would be more iguanas with webbed feet and flat tails. C) There would be fewer iguanas with webbed feet. D) The iguanas would no longer be green. There would be more iguanas with webbed feet and flat tails. Because iguanas now had to swim to find food, the iguanas that had webbed feet and short, flat tails were able to survive and reproduce. Over time, more and more iguanas had webbed feet and flat tails.

B) There would be more iguanas with webbed feet and flat tails.

Notice that the appendages of the organisms in the picture contain an overall common structure but different functions. What is the best explanation on why these organisms share a common structure in number and organization of bones? A) These organisms are all of the same species. B) These organisms all evolved from a common ancestor. C) These organisms passed on acquired traits to their offspring. D) These organisms all lived in similar habitats and were therefore under similar environmental pressures. These organisms all evolved from a common ancestor. These organisms share common structure (homologous structures) due to the fact that they all evolved from a common ancestor.

B) These organisms all evolved from a common ancestor.

According to scientists, the organisms in the picture all evolved from a common ancestor. What evidence backs up this theory? A) These organisms are all of the same species. B) These organisms contain very similar bone anatomy. C) The appendages of these organisms share similar function. D) These organisms all lived in similar habitats and were therefore under similar environmental pressures. These organisms Contain very similar bone anatomy.. These organisms share common structure (homologous structures) due to the fact that they all evolved from a common ancestor.

B) These organisms contain very similar bone anatomy.

Scientists believe the first giraffes on Earth had shorter legs and a shorter neck than giraffes today. What can you conclude about these first giraffes? A) They ate both meat and leaves from trees. B) They had food sources that were low to the ground. C) They found it necessary to flee quickly from predators. D) They had abundant sources of water from which to drink.

B) They had food sources that were low to the ground.

African cichlids are a group of closely related fish species. There are at least 500 known species living in three small lakes. Over time, specialized teeth and body colorations have evolved for each species in response to mutations and competition for food and mates. This change over time is an example of A) coevolution. B) adaptive radiation. C) convergent evolution. D) vestigial structures. Adaptive radiation. Adaptive radiation is the rapid evolution of many species, due to fragmented habitats, resources, and competition.

B) adaptive radiation.

The finches that Darwin studied in the Galapagos islands have evolved with different types of beaks: drilling, cracking, tearing, and fishing. This is an example of A) predation. B) adaptive radiation. C) warning coloration. D) protective resemblence. This is an example of adaptive radiation. Adaptive radiation describes the rapid speciation of a single or a few species to fill many ecological niches.

B) adaptive radiation.

Scientists believe that the first life forms to appear on planet Earth were probably similar to which modern organisms? A) viruses B) bacteria C) plant cells D) animal cells Scientists believe that the first organisms to appear on Earth most likely resembled modern bacteria. This is due to the simplicity of these organisms.

B) bacteria

Darwin wrote many of the premises of 'The Theory of Evolution by Natural Selection' by noting differences in the _________ of closely related ______________, while studying in the Galapagos Islands. A) feet, finches. B) beaks, finches. C) feather color, tortoises. D) dietary preferences, tortoises. beaks, finches. Darwin noted that finches had seemed to adapt different bill shapes, according to the food available on their particular island. Their other similarities suggested a common ancestor.

B) beaks, finches.

Chemical analysis of the oxygen isotopes in foraminifera shells allow scientists to create a climate record like the one shown here. The chemical composition of shells depends on the temperature of the surrounding water and the presence or absence of large polar ice sheets. Fossil data like this indicates that A) only simple organisms on Earth are subject to change over time. B) climatic changes can definitely influence changes in life forms. C) change in life forms is more likely to change in marine habitats. D) climatic change does not necessarily result in change in life forms. Fossil data like that illustrated here indicates that climatic changes can definitely influence changes in life forms. Scientists believe that climatic change and change in life forms go hand-in-hand. A similar foraminifera fossil record was used to study climate change around the time of the extinction of the dinosaurs to formulate a hypothesis for their disappearance.

B) climatic changes can definitely influence changes in life forms.

According to evolutionary theory, the cell on the right appeared first. _________________ were among the first photosynthetic forms of this organism. A) algae B) cyanobacteria C) plants D) zooplankton Cyanobacteria. Cyanobacteria were photosynthetic and supplied oxygen to an oxygen deficient environment.

B) cyanobacteria

Suppose that pollution caused snow in the arctic to quickly turn black, which happens sometimes in today's urban areas. To adapt to this change over time, the arctic fox's fur would A) darken in the summer. B) darken in the winter. C) lighten in the summer. D) lighten in the winter. The most evolutionarily advantageous adaptation for the fox would be if its fur would turn darker in the winter. This would both help the fox sneak up on its prey and hide from its predators.

B) darken in the winter.

Stabilizing selection is the most common form of natural selection. It eliminates any extreme expression of a trait in a population of organisms when the average expression leads to a higher rate of survival. Stabilizing selection tends to A) decrease genetic sameness. B) decrease genetic diversity. C) increase the frequency of a rare allele. D) increase the frequency of two rare alleles. Stabilizing selection tends to decrease genetic diversity. This mechanism tends to eliminates extremes, while disruptive selection favors extremes.

B) decrease genetic diversity.

Imagine a field of flowers; a field of flowers that are pollinated by basically three different pollinators. One pollinator, bees, attracted to short plants. Another, butterflies, prefer plants of medium height and a third pollinator, birds, visits only the tallest plants. Pesticide spraying kills many insect pests in the field of flowers but also wipes out the butterfly population. If the pollinator that preferred plants of medium height, the butterflies, disappears from the area, medium height plants would be selected against and the population would tend toward both short and tall, but not medium height plants. Such a population, in which multiple distinct forms or morphs exist is said to be polymorphic. This is also an example of ____________ selection. A) directional B) disruptive C) environmental D) stabilizing This is an example of disruptive selection. In disruptive selection, selection pressures act against individuals in the middle of the trait distribution

B) disruptive

If you have ever been to a natural history museum, you have probably seen large fossils of dinosaurs. These fossils are not actually bones, but hardened minerals which have replaced the bone over time. Despite the fact that we have a record of these ancient animals, they no longer roam the earth, due to ____________. A) adaptation B) extinction C) extraction D) pollution extinction Sometimes species change slowly over time, but sometimes they can die off altogether.

B) extinction

Many gardeners use a chemical weed-killer to control plant pests in their gardens. However, many weeds have begun to develop a resistance to these chemical poisons. The resistance that the weeds have developed may be passed down to future generations through _________ . A) apoptosis B) genes C) mitosis D) revolution Any trait passed down from parent to offspring is riding on the backs of genes.

B) genes

According to evolutionary history and taxonomy, tigers resemble ____________ more closely than they resemble fish. A) hydra B) gorillas C) sea urchin D) grasshoppers Gorillas. Tigers share many more characteristics with primates, like gorillas, than they share with fish and other "lower" organisms. Tigers and gorillas are both higher vertebrates, while fish are considered primitive vertebrates.

B) gorillas

Which term describes body structures in different organisms that have different outward appearances but develop from the same embryonic tissues? A) analogous B) homologous C) remedial D) vestigial Homologous structures is the term used to describe body structures in different organisms that have different outward appearances but develop from the same embryonic tissues.

B) homologous

Identify the BEST way to determine if two organisms are closely related. A) comparing body plans B) molecular homology (comparing DNA) C) identifying and comparing homologous structures D) comparative embryology (comparing embryonic development) molecular homology (comparing DNA) Although all of answers, if similar, would suggest degrees of relatedness, the BEST way to determine how closely two organisms are related is through DNA comparison. The more similar the DNA, the greater the degree of relatedness.

B) molecular homology (comparing DNA)

Many gardeners use a chemical weed-killer to control plant pests in their gardens. However, many weeds have begun to develop a resistance to these chemical poisons. This is an example of _________________ in action. A) hybridization B) natural selection C) polynuclueization D) chemical selection Developing an ability over several generations in response to environmental stimuli is a short definition of natural selection.

B) natural selection

Which term best demonstrates when an organism is better adapted to the environment that they live in and are more likely to survive and reproduce? A) natural variation B) natural selection C) speciation D) living Natural selection is the process by which organisms are better suited for their environment. Because they are better suited, they are more likely to survive and reproduce. This is also known as survival of the fittest.

B) natural selection

The fossil image is of a trilobite. Trilobites lived in the ancient seas and the fossil was found in the sea floor. Compare the fossil to the four modern-day animals also pictured. Based on physical evidence, the trilobite is probably a direct ancestor of what animal? A) locust B) pillbug C) scallop D) roundworm pillbug If you compare the shape of the body and pattern of the exoskeleton, you will see the similarities.

B) pillbug

All BUT one factor contributes to natural selection. That factor is A) mutation. B) population stability. C) environmental factors. D) differential reproduction. Population stability will not be a driving force behind genetic change. For natural selection to occur there must be genetic variation, that could be the result of mutation or sexual reproduction. There is differential reproduction and finally there is heredity.

B) population stability.

Prior to the time of Charles Darwin, it was widely believed that all organisms appeared on Earth at the same time and remained unchanged throughout history. Which of these proved to be the biggest influence in the development of this idea? A) scientific data B) religious beliefs C) Mendel's work with pea plants D) Lamarck's idea of acquired characteristics Religious beliefs, the Church, and religious leaders were the major influence in the development of early evolutionary ideas. For many years, it was an accepted belief that all organisms appeared on Earth at the same time and have never changed. Scientifically, we can prove that organisms do change over time and not all organisms have been on Earth since its beginning.

B) religious beliefs

To ensure its survival, any species must be able to A) kill competitors. B) reproduce successfully. C) obtain enough energy through food. D) maintain internal body homeostasis. Reproduce successfully. On the species level, this is what is required to avoid extinction. Individuals need to do the first two, but indivuals dying does not necessarily doom the species as a whole.

B) reproduce successfully.

All the finches Charles Darwin observed on the Galapagos Islands A) behaved in the same way. B) shared a common ancestor. C) had the same shaped beaks. D) sang the same kind of song. All the finches on the Galapagos Islands shared a common ancestor. Through separation on the different island chains that had different resources, the one species of finches evolved into many species.

B) shared a common ancestor.

What did Charles Darwin mean when he stated that some organisms were 'more fit' than other organisms? A) some organisms were heavier and stronger B) some organisms were more likely to reproduce C) not all organisms had the same natural life span D) not all organisms were equally suited to gathering food Organsisms that were more fit were,according to Darwin, more likely to reproduce than organisms that were less fit.

B) some organisms were more likely to reproduce

According to Darwin, organisms that are best adapted to their environment are more likely to produce offspring than organisms that are less well adapted to their environment. Which phrase is used to summarize this idea? A) species variability B) survival of the fittest C) use and disuse of organs D) evolution through mutation Survival of the fittest refers to the observation by Darwin that organisms that are better adapted to their environment ('more fit') are more likely to survive and reproduce than organisms less well adapted.

B) survival of the fittest

Approximately 2 million years ago the genus Australopithecus gave rise to a new genus, Homo. Today, we retain the genus as Homo sapiens. What important fossil evidence MOST likely helped scientists change the classification of those early human ancestors? A) opposable thumb B) teeth and skull size C) pelvis and leg bones D) spine alignment and foot size The correct answer is teeth and skull size. The Homo genus had smaller teeth and a larger skull with some shape modifications that allowed for larger brain volume. Scientists also used behavior to help separate the two; Homo began to use primitive tools.

B) teeth and skull size

Prior to the ideas presented by Charles Darwin concerning evolution, several alternating theories had been developed. They included all BUT A) all species on Earth were created at the same time and have never changed. B) the DNA differences within a species lead to some individuals being better able to survive. C) new animals were simply made from the different parts of animals that were living at the time. D) an organism can acquire characteristics during their lifetime and then pass these onto future generations. All of these were theories of evolution prior to Darwin except the DNA differences within a species lead to some individuals being better able to survive. This idea is the basis of Darwin's, and the one most widely held to be true today. The other answer choices all presented ideas developed in the past, and all have been discredited.

B) the DNA differences within a species lead to some individuals being better able to survive.

Thomas Malthus' most well known work An Essay on the Principle of Population was published in 1798, although he was the author of many pamphlets and other longer writings. The main ideas of his argument on the human condition were radically opposed to current thinking at the time. He argued that increases in population would eventually diminish the ability of the world to feed itself and based this conclusion on the thesis that populations expand in such a way as to overtake the development of sufficient land for crops. The main idea of Malthus' article as described above is analogous to A) Lamarck's theory of use and disuse. B) the concept of population and carrying capacity. C) Darwin's ideas regarding survival of the fittest. D) the belief that inherited variations in a population increase an individual's ability to compete, survive, and reproduce. The main idea of Malthus' article as described above is analogous to the concept of population and carrying capacity. Malthus' view was that poverty and famine were natural outcomes of population growth and a limited food supply. Any population requires a certain amount of natural resources in order to survive. If any of the basic resources are limited, survival declines.

B) the concept of population and carrying capacity.

Natural selection would favor which of the these rabbits in Antarctica? A) brown rabbit B) white rabbit C) black rabbit D) white-and-black rabbit A white rabbit would be favored by natural selection in Antarctica because it would blend into the snow covering the land. By blending in, the white rabbit would avoid predators, and reproduce more successfully than other color rabbits.

B) white rabbit

There have been many attempts over time to explain the mechanism behind the evolution of living organisms. Two of the better known theorists include Charles Darwin and Jean Baptist Lamarck. How would Lamarck's explanation of the evolution of long necked giraffes differ from Darwin's explanation? A) According to Lamarck, giraffes evolved due to environmental pressures; those giraffes with better traits would pass on traits to offspring, and according to Darwin, inherited traits were passed to offspring. B) Since they both believed in the same mechanism for evolution, both would agree that long necked giraffes evolved because the more giraffes stretched their necks, the better fit for the environment, and this trait was passed down to offspring. C) According to Lamarck, long necked giraffes evolved because they spent the majority of their time stretching their necks and this trait was passed down to offspring; according to Darwin, giraffes with longer necks had the advantage in the environment and survived, reproduced, and passed this trait on to offspring. D) According to Darwin, long necked giraffes evolved because they spent the majority of their time stretching their necks and this trait was passed down to offspring; according to Lamarck, giraffes with longer necks had the advantage in the environment and survived, reproduced, and passed this trait on to offspring. According to Lamarck, long necked giraffes evolved because they spent the majority of their time stretching their necks and this trait was passed down to offspring; according to Darwin, giraffes with longer necks had the advantage in the environment and survived, reproduced, and passed this trait on to offspring. Lamarck believed in the inheritance of acquired characteristics, meaning that any behavior or trait acquired during an organism's lifetime would be passed on to offspring. Darwin believed that the organisms most suited to the environment survived, reproduced, and passed these advantageous traits on to offspring. Those not well adapted died.

C) According to Lamarck, long necked giraffes evolved because they spent the majority of their time stretching their necks and this trait was passed down to offspring; according to Darwin, giraffes with longer necks had the advantage in the environment and survived, reproduced, and passed this trait on to offspring.

James was sick, went to the doctor, and was diagnosed with a bacterial throat infection. His infection was treated with antibiotics. In a few days, James felt much better, but some resistant bacteria survived and, overnight, James was sick again. This time, he had to take a much stronger antibiotic. The resistant bacterial cells illustrate what characteristic of life? A) All living things respond to stimuli. B) All living things maintain homeostasis. C) All living things adapt to changes in their environment. D) All living things contain genetic material and reproduce. All living things adapt to changes in their environment. This is one part of the evolution picture. The "new" bacteria in this situation were resistant to the first antibiotic and survived. They will pass this resistance to their off-spring.

C) All living things adapt to changes in their environment.

All of the following EXCEPT the resistance of _________ demonstrate artificially selected resistance. A) beef cattle, to "shipping fever", B) many agricultural wheat varieties, to drought and fungus, C) Antarctic fish to freezing, due to antifreeze proteins in their blood, D) many common grasshopper species to pesticides, such as diazinon, sevin, and others, The resistance of Antarctic fish to freezing, due to antifreeze proteins in their blood. This is the only answer choice where natural selection is working, and not artificial selection by human means.

C) Antarctic fish to freezing, due to antifreeze proteins in their blood,

The above image shows four different finches that Charles Darwin found while on the Galapagos Islands. This information led Darwin to develop the idea that organisms change, or evolve, over time. Which of these would best describe what Darwin saw as the MAJOR difference(s) between these finches? A) They all ate different food B) They all lived in different areas C) Both where they lived and what they ate were different D) Only their beak size was different and they lived together and ate the same food. The finches had different shaped beaks, and Darwin noticed that both where they lived and what they ate were different. Their beaks evolved over time, and that allowed the different finches to be able to live in different places and eat different food.

C) Both where they lived and what they ate were different

Four species of finch arrive on a newly formed Galapagos island, which is covered with cacti growing in loose, dry sand. The cacti have honey-filled flowers and tiny seeds. The theory of evolution by natural selection would probably predict that ____________________ would most succesfully survive, because _________________________. A) Geospiza magnirostris; its large size makes it the fittest. B) Geospiza fortis; it will probably be able to dig up worms with its bill. C) Certhidia oliveacea; its tiny pointed bill is the best adapted to sip nectar. D) Geospiza parvula; animals with intermediate traits tend to have higher survival rates in new places. Certhidia oliveacea; its tiny pointed bill is the best adapted to sip nectar. This finch is the most fit to survive in its new environment.

C) Certhidia oliveacea; its tiny pointed bill is the best adapted to sip nectar.

Farmer Brown grows corn for a living. One day, Farmer Green suggests to Farmer Brown that he should clone his best corn plant in order to produce more ears of corn per plant. Farmer Brown is not sure about Farmer Green's idea. Why might Farmer Brown be hesitant to clone his corn? A) Cloning the corn plants is difficult and expensive to accomplish. B) The cloned corn would not have the same taste as the original plants. C) Cloning eliminates the ability to sexually reproduce and provide genetic variability. D) Cloned plants would have increased genetic variability as well as a shortened life expectancy. Cloning eliminates the ability to sexually reproduce and provide genetic variability. . Genetic variability is essential for the long-term survival of the species as the strongest plants would best survive and reproduce. If a disease came in that affected one of the cloned plants, all of the others would be affected as well, while the genetic variability of the naturally-reproducing plants might provide some survival abilities.

C) Cloning eliminates the ability to sexually reproduce and provide genetic variability.

Human evolution from its first separation from the last common ancestor of humans and chimpanzees is characterized by a number of changes. The most significant of these are bipedalism, increased brain size, lengthened gestation and infancy, and decreased sexual dimorphism. Bipedalism is the basic adaptation of the hominin and is considered the main cause behind skeletal changes shared by all bipedal hominins. Anatomically, the evolution of bipedalism was accompanied by a large number of skeletal changes, not just to the legs and pelvis, but also to the vertebral column, feet and ankles, and skull. The images above all illustrate the presence of a vestigial structure. What is this structure and why is it no longer used for its original function? A) Sacral vertebrae have disappeared in modern man. They are no longer needed as man stood more and more upright. B) Lumbar vertebrae. As man became bipedal, the vertebrate became shorter and wider. These particular vertebrate disappeared. C) Coccyx or tailbone is the remanent of a lost tail. The tail was used for gripping as well as an aid in balance and mobility. D) Iliac blade. This part of the pelvis was shortened and widened as a requirement for keeping the center of gravity stable while walking. Coccyx or tailbone is the remanent of a lost tail. The tail was used for gripping as well as an aid in balance and mobility. The tailbone is the final segment of the vertebral column in humans and apes, and certain other mammals such as horses. The tailbone has lost its original function in assisting balance and mobility, although it still serves some secondary functions, such as being an attachment point for muscles.

C) Coccyx or tailbone is the remanent of a lost tail. The tail was used for gripping as well as an aid in balance and mobility.

Scientists routinely explore whether two different animal species have evolved from a recent common ancestor. _______________ is the LEAST useful technique to help with this determination. Comparison of items eaten for food is the least useful technique for determining whether two species share a recent common ancestor. Studies of embryological development, anatomical comparisons, and DNA analysis are all tools used to determine the relationships among animal species. A) Analysis of strands of DNA B) Comparisons of bones and muscles C) Comparisons of items eaten for food D) Studies of embryos during development Comparison of items eaten for food is the least useful technique for determining whether two species share a recent common ancestor. Studies of embryological development, anatomical comparisons, and DNA analysis are all tools used to determine the relationships among animal species.

C) Comparisons of items eaten for food

The MOST accurate way to determine the evolutionary relationship between two animals is through the examination of A) common behaviors. B) similar physical features. C) DNA or protein sequences of shared genes. D) fossilized ancestors that they may have in common. DNA or protein sequences of shared genes. Biochemical evidence is extremely accurate in determining the relationship between two organisms. Many animals have been re-classified, due to DNA evidence.

C) DNA or protein sequences of sared genes.

The amino acids for beta hemoglobin found in five species were compared to the amino acids found in human (Homo sapiens) beta hemoglobin. The number of sequence differences was recorded. Based on the molecular data, which species is most closely related to humans? A) Lemur catta (lemur) B) Hylobates lar (gibbon) C) Gorilla gorilla (gorilla) D) Macaca mulatta (Rhesus monkey) Gorilla gorilla (gorilla) There is only one difference in the amino acid sequences between humans and gorillas. Therefore, they would be considered most closely related. Least related would be the lemur.

C) Gorilla gorilla (gorilla)

The table is showing you the amino acid sequence of the same protein in different organisms. What information can you gain by analyzing this table? A) It can show you chromosomal abnormalities. B) It can show you how well the protein will function in the organism. C) It can show you which organism is most closely related to the human. D) It can show you whether or not the organisms carry a genetic disease. It can show you which organism is most closely related to the human. The more similar the DNA, the greater the degree of relatedness, or the more recent in time the two organisms diverged from a common ancestor. If there is a great difference in DNA sequencing, this suggests that the organisms shared a common ancestor a long time ago.

C) It can show you which organism is most closely related to the human.

A review of the cladogram shows a common ancestor for these four types of vertebrates. Which statement BEST explains the genetics represented by the cladogram? A) There are no genetic similarities among the four distinct types. B) The four types of animals no longer have any genetic similarities. C) Lizards and snakes are more genetically alike than lizards and birds. D) A common ancestor indicates that the four once had identical genotypes. Lizards and snakes are more genetically alike than lizards and birds. All living things share a universal genetic code. What we are is determined by how that genetic code is arranged. The four organisms once shared a common ancestor and similar, although not identical, genetics. Over time, the genetic code of each changed. The branches of the cladogram indicate relatedness so we can say that lizards and snakes are more genetically similar than lizards and birds.

C) Lizards and snakes are more genetically alike than lizards and birds.

Which fact about fossils is MOST important to scientists who study evolution? A) Fossils are often found in sedimentary rock. B) Footprints, body structures, and even animal droppings can become fossilized. C) The age of a fossil can be determined by examining the rock strata in which the fossil is found. D) The formation of a fossil depends on the geologic and chemical conditions present when an organism dies. The age of a fossil can be determined by examining the rock strata in which the fossil is found. Without knowing the relative ages of fossils, scientists would have no way to know the order in which organisms have evolved.

C) The age of a fossil can be determined by examining the rock strata in which the fossil is found.

Hummingbird bill length data was collected and graphed in a particular environment. Based on the data collected, which is the BEST conclusion drawn? A) The environment is selecting against all longer bill length birds. B) Due to natural selection, a virus has killed off all medium bill length birds. C) The environment has a greater amount of long nectar tubed flowers and short nectar tubed flowers causing disruptive selection in medium bill length birds. D) The environment has a greater amount of long nectar tubed flowers and short nectar tubed flowers causing stabilizing selection in medium bill length birds. The environment has a greater amount of long nectar tubed flowers and short nectar tubed flowers causing disruptive selection in medium bill length birds. Disruptive selection, also called diversifying selection, describes changes in population genetics in which extreme values for a trait are favored over intermediate values. In this case, the variance of the trait increases and the population is divided into two distinct groups.

C) The environment has a greater amount of long nectar tubed flowers and short nectar tubed flowers causing disruptive selection in medium bill length birds.

In 1831, Charles Darwin visited the Galapagos Islands. While observing the giant land tortoises that lived on these islands, Darwin noted that the shape of the tortoise shell varied depending on which island the tortoise lived. Tortoises on one island had round shells, for example, whereas tortoises on a neighboring island had more flattened, saddle-shaped shells. Which statement BEST summarizes Darwin's explanation for these differences? A) Random mutations caused the shape of the shells to fluctuate periodically. B) The shape of the tortoise shell varied because the predators on the islands were all similar. C) The particular shape of the shell was best suited for the island on which the tortoise was living. D) Tortoises who used their shells in special ways caused the shells to become larger, rounder, or flatter. The particular shape of the shell was best suited for the island on which the tortoise was living. Darwin reasoned that the particular shape of the shell was related to the ability of the tortoise to survive and reproduce.

C) The particular shape of the shell was best suited for the island on which the tortoise was living.

Apple farmers are currently having a very difficult time with pesticide-resistant insects. These insects are no longer being killed by the current chemical treatments, thus causing a lot of damage to the apple crops. In reaction to this, researchers are developing newer and stronger chemicals to help control the bugs. Why are the apple farmers seeing these new, stronger bugs? A) The bugs were not native to the area and thus cannot be killed by normal chemicals. B) Changes in the weather have led to stronger insects that can survive these harsh changes. C) The strongest bugs were able to survive pesticides, reproduce and create more resistant pests. D) The apple trees are producing too many apples, which is allowing the insects to reproduce rapidly. The strongest bugs were able to survive pesticides, reproduce and create more resistant pests. Most of the bugs did die, but the few strongest that were able to survive and reproduce began to create a new strain of insect that could resist the pesticides.

C) The strongest bugs were able to survive pesticides, reproduce and create more resistant pests.

Which statement is true, with regard to the theory of evolution? A) Evolution of an entire species can often occur in a single individual organism. B) The theory of evolution is proof that evolution occurs exactly as described, and cannot be revised. C) The theory of evolution offers an explanation of how competition for resources may lead a species to change. D) DNA sequences and protein similarities are the only reliable way to determine that an organism evolved from another. The theory of evolution offers an explanation of how competition for resources may lead a species to change. Competition for resources is one of the main points of Darwin's theory. Species adapt, as the struggle to obtain resources to reproduce.

C) The theory of evolution offers an explanation of how competition for resources may lead a species to change.

An earthquake causes a huge canyon to form, permanently dividing a population of wild donkeys. On the windward side of the canyon, dry conditions develop and grasses grow. On the leeward side of the canyon, rainfall is frequent and a forest grows. What is LEAST likely to happen over the course of 100,000 years? A) Two new species of donkeys will form. B) Donkeys from the grassy side could develop zebra striping for camouflage. C) The two populations of donkeys will remain physically identical in both areas. D) Over a long time, even if introduced to each other, donkeys from the grassy side of the canyon, will not be able to reproduce with donkeys on the forest side. The two populations of donkeys will remain physically identical in both areas. The two groups of donkeys will probably undergo speciation and adapt to the two new environments differently.

C) The two populations of donkeys will remain physically identical in both areas.

Sea gulls prey on snails on the rocky sea coast. The snails vary in color from solid brown to brown and tan striped. The birds suck the soft snail bodies out of the shells and leave the shells behind on the rocks. Scientists picked up 500 empty shells and found that 400 of the shells were solid brown and only 100 were striped. Over the years, what would you expect to happen to the snail population? A) The snails would become extinct. B) There would be mostly brown snails. C) There would be mostly striped snails. D) There would be an even number of brown snails and striped snails. There would be mostly striped snails. Since the birds ate mostly brown snails, we can assume the birds could see the brown snails and not the striped snails. Over time, the striped snails would survive and reproduce.

C) There would be mostly striped snails.

Why are the beak sizes and shapes of Darwin's finches different? A) They had different ancestors. B) They adapted to the type of predators. C) They adapted to the type of food available. D) They crossbred with different bird species. The beaks of Darwin's finches are different because of the type of food available. Large beaks are better for islands with larger seeds, while pointed beaks are better for getting insects out of trees.

C) They adapted to the type of food available.

Data was collected concerning Galapagos bird beak size over time. There are 13 types of Galapagos finches, and they are also known as Darwin's Finches. These finches share the same habits and characteristics except for one; they all have different beaks. The differences in their beaks might be the most important aspect of their survival because beak size determines the type of seed able to be eaten. Only the birds with the largest of beaks are able to eat the toughest, biggest, and spine covered seeds. Based on the data given, choose the BEST conclusion. A) This data shows that over time the type of food available remained constant. B) This data shows that the environment did not change over the course of time. C) This data shows a fluctuation in bird species over time most likely due to food availability. D) This data shows a fluctuation in bird species over time most likely due to the inheritance of acquired characteristics. This data shows a fluctuation in bird species over time most likely due to food availability. Percentages are based on environmental pressures. In the years with more birds with a larger beak size, the majority of the food available were big, tough, spine covered seeds. Those birds with a larger beak size survived better during those years. In natural selection, those animals most suited or best adapted to the environment survive and reproduce.

C) This data shows a fluctuation in bird species over time most likely due to food availability.

Naturalist Jean-Baptiste Lamarck promoted the theory of "inheritance of acquired characteristics". This theory stated that changes developed over the course of the life of an organism would be transmitted to the next generation. A famous example involves a blacksmith. Working with heavy hammers, pounding iron all day, blacksmiths developed larger arms than average men. This trait, large and muscular arms, would then be passed down to the children of the blacksmith. Charles Darwin developed a competing theory based on variation and a process he called "natural selection". His theory stressed how the differences among the individuals in a population would lead to different rates of survival and reproduction. Through this process, in conjunction with what he called a "strong principle of inheritance", entire populations could adapt, and ultimately, evolve. The fact that many blacksmith apprentices were not born to blacksmith fathers, and they still developed large arms, would have what impact on Lamarck's theory? A) According to his theory, it would mean that the apprentice's children would definitely have large arms. B) It would weaken it somewhat, because it shows that physical characteristics are mostly linked to one's environment. C) It would strengthen the theory, because of the clear connection between being a blacksmith and having certain physical traits. D) It would weaken it, because it suggests that development of some traits may not be linked to the characteristics of one's parents. It would weaken it, because it suggests that development of some traits may not be linked to the characteristics of one's parents. This is the best answer because it directly refutes Lamarck's claim, that acquired traits are passed down from parents to children.

D) It would weaken it, because it suggests that development of some traits may not be linked to the characteristics of one's parents.

In 1950's, Stanley Miller and Harold Urey showed how organic molecules necessary for the formation of life could be assembled from simple molecules known to have existed on Earth millions of years ago. Evidence from Miller and Urey's experiments suggest that complex organic molecules could be formed from other, simpler molecules. Why is it unlikely that this process is still occuring today? A) Modern amino acids are unlike those that may have existed on the ancient Earth. B) The current environment of the Earth is too polluted to allow the formation of organic molecules. C) The present day Earth lacks sufficient energy to allow the formation of organic molecules to occur. D) Living organisms such as bacteria are likely to interfere in the process by breaking down the organic molecules. Evidence from Miller and Urey's experiments suggest that complex organic molecules could be formed from other, simpler molecules. Why is it unlikely that this process is still occuring today?

D) Living organisms such as bacteria are likely to interfere in the process by breaking down the organic molecules.

In 1967 a penicillin-resistant pneumonia, caused by Streptococcus pneumoniae and called pneumococcus, surfaced in a remote village in Papua, New Guinea. At about the same time American military personnel in southeast Asia were acquiring penicillin-resistant gonorrhea from prostitutes. By 1976, when the soldiers had come home, they brought the new strain of gonorrhea with them and physicians had to find new drugs to treat it. In 1983 a hospital-acquired intestinal infection caused by the bacterium Enterococcus faecium joined the list of bacteria that could not be killed by penicillin. Which of these BEST describes why certain bacteria have become resistant to penicillin? A) The penicillin in the 1970's was much weaker that the penicillin used today, thus it was not as effective. B) Penicillin was not effective in treating any bacterial diseases, so the doctors had to find new treatments. C) These new bacterial strains came out of the jungles and forests already equipped to be penicillin-resistant. D) Penicillin was so heavily prescribed by doctors that it led to certain, more fit, strains of bacteria to be able to survive. Penicillin was so heavily prescribed by doctors that it led to certain, more fit, strains of bacteria to be able to survive.. Researchers thought penicillin was the cure for all, and thus it became overused. Through natural selection, new, stronger strains of bacteria developed.

D) Penicillin was so heavily prescribed by doctors that it led to certain, more fit, strains of bacteria to be able to survive.

For over a decade, farmers in the U.S. have been planting genetically modified crops. An example of one of these crops is corn that is resistant to weed-killer. This makes it so that no corn is lost due to contact with herbicide meant to kill weeds. While this is seen by many as a positive development, others see it as a cause for concern. What is one possible negative side effect of planting genetically modified corn? A) Genetically modified corn, as well as other plants, is unnatural. B) Corn will replace wheat and other crops as our main source of carbohydrates. C) Plants with modified genomes may have a predictable impact on the environment. D) Plants with modified genomes may have an unforeseen impact on the environment. Plants with modified genomes may have an unforeseen impact on the environment. Even though the genetic modification may seem small, how it interacts with an environment outside the lab is nearly impossible to predict.

D) Plants with modified genomes may have an unforeseen impact on the environment.

The diagram documents a famous experiment by Diane Dodd. Dodd took an initial population of Drosophila fruit flies and separated them into two different containers. The first group was fed food containing mostly starch. The second group was fed food containing mostly maltose. After eight generations apart (about four months), the flies were re-introduced and could not longer interbreed. They had become two new species. What is the most likely reason the flies evolved into two species? A) At least one of the groups of flies became sterile and unable to lay eggs. B) The two flies were really separate species to begin with, but it went unnoticed. C) The two different food sources introduced many new DNA mutations very quickly and the flies changed drastically. D) Separation with different food sources gave an advantage to mutant flies that could only digest starch or digest maltose. They survived and the species changed in these directions. Separation with different food sources gave an advantage to mutant flies that could only digest starch or digest maltose. They survived and the species changed in these directions. Likely, flies that could only digest these types of food, carried an advantage in the strict diet environment, and the whole species changed in 2 directions.

D) Separation with different food sources gave an advantage to mutant flies that could only digest starch or digest maltose. They survived and the species changed in these directions.

In 1967 a penicillin-resistant pneumonia, caused by Streptococcus pneumoniae and called pneumococcus, surfaced in a remote village in Papua, New Guinea. At about the same time American military personnel in southeast Asia were acquiring penicillin-resistant gonorrhea from prostitutes. By 1976, when the soldiers had come home, they brought the new strain of gonorrhea with them and physicians had to find new drugs to treat it. In 1983 a hospital-acquired intestinal infection caused by the bacterium Enterococcus faecium joined the list of bacteria that could not be killed by penicillin. A population of bacteria is treated with an antibiotic. Because of variation in the population of bacteria, what is a possible outcome of the treatment? A) The population will increase rapidly. B) All of the bacteria will be resistant to the antibiotic. C) The population will be better able to obtain a food source. D) Some of the bacteria may be resistant to the antibiotic and survive. Penicillin was so heavily prescribed by doctors that it led to certain, more fit, strains of bacteria to be able to survive.. Researchers thought penicillin was the cure for all, and thus it became overused. Through natural selection, new, stronger strains of bacteria developed.

D) Some of the bacteria may be resistant to the antibiotic and survive.

Which pair of organisms show convergent evolution? A) Despite being close relatives, cattle and giraffes have drastically different neck lengths. B) Ducks develop different mating dances to avoid mating with other ducks from different species. C) A bluegill sunfish and a redear sunfish, closely related, have similar fin shapes and color patterns. D) Tasmanian devils and wolverines are both thick-bodied predators with crushing teeth and similar food sources, but they are not at all related. Tasmanian devils and wolverines are both thick-bodied predators with crushing teeth and both eat carrion, but they are not at all related. In convergent evolution, unrelated organisms adapt similar features to deal with similar environments.

D) Tasmanian devils and wolverines are both thick-bodied predators with crushing teeth and similar food sources, but they are not at all related.

Which statement is true about fossils? A) There are more fossils in warm, wet tropical areas. B) No fossils resemble organisms that are presently alive. C) The oldest fossils are found in layers closest to the surface. D) The complexity of the organisms in fossil beds increases closer to the surface. The complexity of the organisms in fossil beds increases closer to the surface. The most recent fossils are found at the surface. Therefore the most advanced fossils are found closer to the surface, as a rule.

D) The complexity of the organisms in fossil beds increases closer to the surface.

Matthew has discovered a new species of fish. During the summer months, the male fish separate themselves from the female fish and swim to cooler waters. During one summer, a volcano erupts and the molten rock forms a barrier preventing the male and female fish from reuniting. A) The species would not be affected by the barrier. B) The male fish would begin to produce eggs and sperm. C) The fish would develop legs and walk across the barrier. D) The fish would become extinct as they would not be able to reproduce. The fish would become extinct as they would not be able to reproduce.. Reproduction is essential to the overall survival of a species. Without it, no new organisms can be produced and eventually, they would become extinct.

D) The fish would become extinct as they would not be able to reproduce.

The key difference between sexual and natural selection is that natural selection acts on traits which increase fitness, whereas sexual selection favors any adaptation which enhances mating success. Differentiate between the two by choosing the example of sexual selection. A) The non-poisonous king snake coloration mimics that of the poisonous coral snake. B) Over time, different sized and shaped finch beaks evolved to suit the food source available. C) The antibiotic resistance of some disease-causing bacteria, making it almost impossible to kill the bacteria with medication. D) The male twelve-wired bird of paradise brushes the female's face with the dozen stiff feather shafts protruding from his lower torso. The male twelve-wired bird of paradise brushes the female's face with the dozen stiff feather shafts protruding from his lower torso. In an act that scientists call "wire-wipe display," during courtship the male twelve-wired bird of paradise repeatedly brushes the female's face with the dozen stiff feather shafts protruding from his lower torso. The female finds the sensation appealing and often approaches the male from behind to place her head among his "wires."

D) The male twelve-wired bird of paradise brushes the female's face with the dozen stiff feather shafts protruding from his lower torso.

Farmer Fran sprays her sugarcane field with a highly effective pesticide called 'Bayou Bug Blast'. For five years the pesticide works without a hitch, effectively killing almost all of the bayou weevils trying to eat Farmer Fran's crop. However, during the 6th year, some of the crop takes a hit. During the 7th year, she loses half of her crop, and during the 8th year, she loses almost the entire cane field to bayou weevils, despite using twice the usual dose of Bayou Bug Blast. What happened? A) The sugar cane became used to the pesticide, rendering it ineffective. B) Bayou weevils over-populated, because Bayou Bug Blast killed all of the predatory insects. C) A small population of weevils survived on other food sources and returned to the sugar cane field to feed. D) The weaker weevils were killed, and Farmer Fran accidentally caused only pesticide-resistant beetles to survive. The weaker weevils were killed, and Farmer Fran accidentally caused only pesticide-resistant beetles to survive. This is a classic case of survival of the fittest in artificial selection.

D) The weaker weevils were killed, and Farmer Fran accidentally caused only pesticide-resistant beetles to survive.

The genetic information in human and chimpanzee DNA shows a high degree of similarity, as humans share about 96-99% of their DNA code with chimpanzees. What is an explanation for this similarity? A) They evolved from each other. B) They evolved at the same time. C) Their evolution is nearly complete. D) They evolved from a common ancestor. They evolved from a common ancestor. Evolutionary theorists say that humans and chimpanzees had a common ancestor, though the link has not yet been found.

D) They evolved from a common ancestor.

A population of fruit flies on an island lay their eggs in some rotting fruit. Some of the fruit is blown into the ocean by a storm and washes up on another island that is too far apart for the flies to fly back to their original island. Over time the two populations change so much that they are different species. What must be true of the two populations of flies at this point? A) They will be genetically identical. B) They will share no genetic material. C) They will be able to produce fertile offspring. D) They will not be able to produce fertile offspring. Different species are not able to produce fertile offspring with one another.

D) They will not be able to produce fertile offspring.

Look at the picture showing the difference between punctuated equilibrium and gradualism. What provides the best evidence for gradualism? A) Mass extinctions B) Adaptive radiation C) Convergent evolution D) Transitional fossils Transitional fossils Gradualism is the idea that large changes are actually the culmination of very small changes that build up over time. Transitional fossils are fossils in the record that show structural adaptations of species as they transform into new species slowly over time. Punctuated equilibrium is based on the idea that we see a quick burst of change in a species and then very long periods of no change.

D) Transitional fossils

Bed bugs might sound like an old-fashioned problem, but now they are back with a vengeance. Fifty years ago, the blood-sucking pests were nearly eradicated in the United States thanks in part to the use of pesticides like DDT. Today, they are creeping over sheets and tormenting sleepers across the country. New York was recently declared America's most bed-bug-infested city in America. In the past, we countered the bed bugs by using pesticides called pyrethrins and pyrethroids. These compounds work by attacking the nervous system. Insects have channels in the membranes of their nerve cells that can be opened to allow sodium into the cells, triggering a nerve impulse. Pyrethrins and pyrethroids alter the nervous system by binding to the sodium channels, locking them in the open position. This allows sodium to pour into the cell continuously, causing the nerve to fire repeatedly and eventually leading to paralysis. Todays bed bugs seem to be more resistant to the chemicals. Biologists have determined that mutations are responsible for this resistance. Mutations changing just two of the 2000 amino acids that make up part of the sodium channels would be enough to make an insect 250 times more resistant to a commonly used pyrethroid. These mutations may change the channel so that the insecticide can no longer bind to it effectively. If bed bugs had never been exposed to DDT in the 1950's and 1960's, how would you expect that to affect bed bugs' resistance to pyrethroids during the last decade? A) Because bed bugs reproduce so rapidly, resistance to pyrethroids among bed bugs has become a major problem. B) With the widespread use of DDT, pesticide-resistant mutations became much more common among bed bugs. The bed bugs passed that resistance on to future generations. C) If some of the bed bugs carry the resistance mutations, those insects will be better able to survive and reproduce and will wind up passing the mutation on to their offspring. D) Without the use of DDT, natural selection would not have favored any mutations that provided protection from pesticides; bed bugs would be more susceptible to today's chemicals. Without the use of DDT, natural selection would not have favored any mutations that provided protection from pesticides; bed bugs would be more susceptible to today's chemicals. Without the DDT spraying, the mutation might not have been favored and todays bed bugs would be less resistant to modern sprays.

D) Without the use of DDT, natural selection would not have favored any mutations that provided protection from pesticides; bed bugs would be more susceptible to today's chemicals.

In vertebrate animals, the same organ in different species often have different structures. For example, the heart of a fish has two chambers while the heart of a mammal has four chambers. What is an explanation for these differences in organ structure? A) reproductive differences B) differences in the size of the animals C) mutation of the genes of the organisms D) adaptation of organisms to their environments Natural selection causes the organisms the are best adapted to their environments to survive and reproduce. Over large amounts of time this leads to differences in organisms that live in different habitats.

D) adaptation of organisms to their environments

During the Industrial Revolution, the dark peppered moth had an advantage because it A) was larger and hardier. B) reproduced easily and quickly. C) was poisonous to many of its predators. D) blended in with the soot from the factories. The dark peppered moth had an advantage because it blended in with the soot from the factories, which protected it from predators. The light peppered moth could not blend in and the population decreased at high rates. This changed the composition of the population in just a few generations.

D) blended in with the soot from the factories.

Scientists believe that land plants, such as the examples seen here, evolved from single-celled green algae. Single-celled algae first evolved a colonial form, as noted in Volvox, and eventually developed organs for reproduction as well as food and water conduction. One key process in this evolution was A) mitosis. B) cell replication. C) genetic continuity. D) cell differentiation. In order to evolve from a single celled aquatic photosynthetic organism to a multicellular land plant, many changes needed to take place. The first place the changes began was with cell differentiation. In a typical land plant, there are many types of cells that have various functions. Some cells are organized into tissues and organs. We can see this process at work today when undifferentiated cells, or meristems, are used in vegetative propagation. These undifferentiated cells are capable of making shoots and/or roots.

D) cell differentiation.

Suppose that the four species of finches shown at the top of the picture above, are all released onto an island in the middle of the ocean. The only species of plant is the betel palm, shown below. The betel palm produces large nuts with a tough outer husk. According to the law of natural selection, which species of finch probably has the greatest chance to survive over the long term? A) finch species 2 B) finch species 3 C) finch species 4 D) finch species 1 Finch species 1 has the largest and strongest beak. The beak of this finch will help it eat the large nut.

D) finch species 1

20,000 years ago, two populations of the black-tailed rats became separated from each other by the formation of a large canyon, thus preventing their interbreeding. The condition described is A) mass extinction. B) selective breeding. C) adaptive radiation. D) geographic isolation. New species develop from an original population through geographic isolation. The species is separated andprevented from interbreeding. Eventually two species will result.

D) geographic isolation.

Evidence for evolution includes the presence of _______________________, which are similar structures shared by different species. A) gradual structures B) vestigial structures C) integrated structures D) homologous structures Homologous structures are those features or organs that are shared by very different species (ex. forelimbs bones in bats and penguins).

D) homologous structures

The bones in the front limbs of many mammals are similar in their structure and arrangement. What term is used to describe physical similarities between related species that indicates a common ancestry? A) vestigial organs B) convergent anatomy C) embryonic parallels D) homologous structures Similar body structures among closely related species are known as homologous structures. Homologous structures are considered to be evidence of a shared ancestry.

D) homologous structures

The wing of a bird and the leg of a horse are very different looking structures. Although they look different, bird wings and horse legs are very similar in the arrangement of the bones that make up the limb. Which term is used by scientists to describe structures that look different on the outside but are actually similar in construction and develop from the same embryonic tissues? A) common descent B) ancillary anatomy C) vestigial structures D) homologous structures Structures of organisms that may look different but have strong similarities in construction and come from the same embryonic tissues are called homologous structures.

D) homologous structures

In 1809, Lamarck developed one of the first theories of evolution called the A) independent assortment. B) survival of the fittest. C) inheritance of variations. D) inheritance of acquired characteristics. Inheritance of acquired characteristics is the false idea that organisms change in order to meet the needs of their environment.

D) inheritance of acquired characteristics.

Horses are much larger today than their two-foot tall ancestor, mesohippus. Geologists believe the change in size was the result of changing environments, from tropical forests to a grassland habitat. Larger size would be an advantage for survival in this new habitat because A) taller horses could reach the leaves that grow high on trees. B) larger horses could find food easier than the shorter horses. C) the larger horses were better camouflaged than the smaller horses. D) larger horses had longer legs and could run faster to escape predators. Larger size would be an advantage for survival in this new habitat because larger horses had longer legs and could run faster to escape predators. The open grasslands made it easier for predators to see the grazing horses, so in order to survive, the horses had to run fast to escape them.

D) larger horses had longer legs and could run faster to escape predators.

Fifty years ago, bed bugs were nearly eliminated in the United States by using of pesticides like DDT. Today bed bugs are back in beds and theaters. DDT is no longer used due to environmental issues. Pyrethrums are currently the top choice for bed bug infestations. Pyrethrums are especially useful to us because they generally have a stronger effect on bugs than on humans and animals. Some bed bugs had mutations in their genetic code which allowed them to survive the chemical pesticide and they produced chemically resistant offspring. How can this be explained? A) mutations were planned out by the bugs B) bed bugs chose other bugs to partner with who had the mutation C) bed bugs chose other bugs to partner with who had no mutations D) mutations involved the genetic variation of the bugs are random The mutations involved the genetic variation of the bugs are random. Some variations are favorable for the organisms environment and some variations are not.

D) mutations involved the genetic variation of the bugs are random

According to Darwin's theory of evolution, which organisms are BEST able to survive in nature? A) those with the best camouflage and coloration B) organisms that possess the greatest number of mutations C) those that possess characteristics acquired during their lifetime D) organisms that possess overall characteristics best suited to their environment

D) organisms that possess overall characteristics best suited to their environment

If scientists wanted to learn more about evolutionary history, they would study all but one of these molecules. Which biological molecule would NOT offer much information about the history of life? A) DNA B) proteins C) nucleic acids D) phospholipids The sequence or arrangement of phospholipids is not determined by the genetic history of an organism. Phospholipids are chemically similar in all cells.

D) phospholipids

Which theory of how evolution occurs would argue that all of the oak species in Georgia appeared suddenly from one common ancestor, over a short period of time, due to some extreme environmental changes, and that since that time, they have not changed much? A) gradualism B) microevolution C) macroevolution D) punctuated equilibrium Punctuated equilibrium. This theory of how evolution works, holds that environmental extremes cause rapid evolution, followed by long periods, when the environment remains relatively stable and the organisms in it do not change much.

D) punctuated equilibrium

Natural selection can lead to the formation of a new species which is called A) fitness. B) mutations. C) selection. D) speciation. Speciation is the term used to describe the formation of a new species due to natural selection.

D) speciation.

Fifty years ago, bed bugs were nearly eliminated in the United States by using of pesticides like DDT. Today bed bugs are back in beds and theaters. DDT is no longer used due to environmental issues. Pyrethrums are currently the top choice for bed bug infestations. Pyrethrums are especially useful to us because they generally have a stronger effect on bugs than on humans and animals. However, bed bugs have become resistant to even this chemical pesticide. What happened that allowed the bug population to increase? A) the chemicals used currently are weaker B) the chemicals no longer can penetrate bed bugs brains C) the bed bugs of today are exactly the same as the bed bugs of fifty years ago D) the bed bugs that survived the DDT years ago, reproduced new generations of chemical resistant offspring The bed bug population has increased because the bed bugs that survived the DDT years ago, reproduced new generations of chemical resistant offspring.

D) the bed bugs that survived the DDT years ago, reproduced new generations of chemical resistant offspring

According to Charles Darwin's theory of natural selection, A) people control evolution. B) the fastest species always survive. C) the strongest species always survive. D) the fittest species survive. Natural selection states that the fittest species survive. Thefittest species are able to reproduce more than those that are not well-adapted, and this causes a change in the make-up of populations favoring the well-adapted species.

D) the fittest species survive.

In 1859, Charles Darwin described a model of how living things change over time. He described this model and the evidence that supported it in a book called On The Origin of Species. Which scientific term is used to describe a testable model that seeks to explain natural phenomena? A) data B) hypothesis C) observation D) theory A theory is a testable model that seeks to explain natural phenomena. Charles Darwin's model of how evolution occurs has been called a theory of evolution.

D) theory

In order for natural selection to occur, Charles Darwin stated we must begin with a population of organisms that has genetic A) competition. B) engineering. C) reproduction. D) variation. In order for natural selection to occur, Charles Darwin stated we must begin with a population that has genetic variation. The genetic variation allows some members of the population to have traits, like a certain color, that helps them to survive. If an organism survives, it reproduces, and then passes those traits on to the offspring.

D) variation.

One of the major elements of natural selection is that all species have genetic A) digression. B) melanism. C) stability. D) variation. Variation. Organisms in a population must have variety so that response to natural pressures can occur. Lack of variety can be deadly to a species.

D) variation.

Darwin theorized that the finches on the Galapagos Islands were related because the finches A) had the same size beaks. B) ate the same kind of food. C) sang the same kind of song. D) were the same size and color. The finches shared many physical characteristics. They were the same size and color. This evidence led Darwin to conclude that they all evolved from the same species. Other factors such asgenetic similarities are used to determine if species are closely related.

D) were the same size and color.