Biology 1407 Lesson 11 Review

Darwin returned from his expedition on the HMS Beagle in 1836, but did not present his theory of natural selection to the Linaean Society until

1858. Darwin did not present his theory until he was almost "scooped" by Wallace.

With which of the following ideas would Lamarck not agree?

A purple-flower-loving cow is grazing in a field with purple and white flowers. The next year white flowers will dominate the population of flowers in the field. Lamarck would not agree with this idea because the flowers do not have any influence on what flower color is acquired by their offspring. He believed that those organs or traits that become more developed will be passed on to offspring, and he called this inheritance of acquired characteristics.

The process of artificial selection demonstrates that:

A range of variation exists within members of a species. Artificial selection is the selective breeding of plants and animals in order to get offspring with desired traits. For example, wild mustard has been selectively bred over many generations yielding the vegetables broccoli, brussel sprouts, kale, cabbage, and cauliflower. The process of artificial selection demonstrates that variation exists between members of a given species and that certain traits can be selected for. The process of artificial selection demonstrates that some of the mechanisms underlying natural selection exist.

Coevolution refers to the process by which

B and C Coevolution refers to the process through which the interactions of species affect the evolution of those species. In coevolution, the change in one species may produce selective pressures that drive the change in another species. Most species on earth have evolved through coevolution with other organisms with whom they interact.

The greatest period of evolutionary diversification occurred during the

Cambrian period. The greatest period of evolutionary diversification occurred during the Cambrian period, in what is often referred to as the "Cambrian explosion". Most modern animal phyla have their roots in this period.

During what period did the dinosaurs suddenly disappear from the record?

Cretaceous, 65 million years ago The dinosaurs disappeared from the record during the Cretaceous, 65 million years ago.

Scientists think that a continental collision resulted in a mass extinction during which period?

Devonian The crashing of the continents disturbed the tropical seas. This probably resulted in a decrease in ocean temperatures.

One of the propositions of Darwin's theory of evolution by natural selection is "survival of the fittest." The phrase means that:

Different individuals leave different numbers of descendants. Charles Darwin's theory of evolution by natural selection has four propositions which are: (1) individuals of a population of species are not identical; (2) some of the variations are heritable (can be passed on to offspring); (3) all populations have the potential to populate the earth but don't; (4) different individuals leave different numbers of descendents. The fourth proposition describes the concept of fitness. The fittest individuals in a population are those that leave the greatest number of descendents. The aspect of fitness is a relative, not an absolute, term. For example, a member of an insect population may produce only a few eggs. Although its reproduction is low, if it produced more eggs than any other member of the population it would be by definition the "fittest" member of the population. The example shows that natural selection does not necessarily produce organisms that are perfectly suited to their environment. The process selects the fittest choice available.

Lamarck would explain the evolution of a giraffe's long neck in which of the following ways?

Each generation, giraffes' necks became a little more elongated by stretching to reach leaves in trees. The giraffes passed the acquired elongation on to their offspring, so the offspring have longer necks than their parents. Lamarck believed that evolution responded to an organism's "felt needs." A need produced by the environment would result in a change in an organism during the organism's lifetime. This change could then be passed on to the offspring of the organism.

Which of the following is true about the mass extinction that occurred during the Ordovician period?

Eighty-five percent of the species (all of which were marine) were wiped out. Because of the falling ocean levels and a decrease in ocean temperatures, many species became extinct.

Which of the following ideas was common to both Darwin and Lamarck?

Evolutionary adaptation results from interactions between an organism and its environment. Lamarck and Darwin both believed that evolution involved the interaction between organisms and their environment.

What was Fitzroy's contribution to the development of evolutionary theory?

Fitzroy believed in stability of the species and argued furiously with Darwin about his new ideas. Fitzroy acted as a great sounding board for Darwin and helped him to crystallize his ideas about evolution.

Which statement about fossils is not true?

Fossils generally contain large quantities of organic substances from the dead organism. Fossils generally do not consist of large quantities of organic matter from the dead organism. The organic matter will usually decay before it can be fossilized. Exceptions to this occur when the organism is trapped in an environment such as resin, ice, or acid, in which the natural process of decay is prevented.

Based on studies of the grazing ecosystem of the Serengeti Plains in East Africa, interesting adaptations have been observed amongst herbivores and the plants that they feed on. The studies show that herbivores graze off the tops of plants and that their grazing may contribute to the evolutionary success of species that can withstand grazing. Given this information, identify which of the following would not represent evidence of coevolution.

Grasses that grow inside enclosed areas protected from grazing have more vegetation per unit area than grazed areas. The studies showed that protected areas had less vegetation / cm3 than grazed areas, indicating that the grasses had successfully adapted to grazing conditions.

Which statement regarding the works of Jean Baptiste Lamarck is incorrect?

He was a contemporary of Charles Darwin. Jean Baptiste Lamarck lived from 1744 to 1829. Charles Darwin was not born until 1809.

Which of the following questions does modern biology not emphasize?

How do we describe an organism's appearance? Modern biology tends to emphasize questions that answer the question "Why?" and often these questions are evolutionary in nature. Prior to Darwin, biology was a descriptive science, concerned with documenting organisms' features and locations.

A good example of coevolution is the interaction of

Hyracotherium and the dominant vegetation of the time. A good example of coevolution is the interaction of Hyracotherium and the dominant vegetation of the time. The changes in the vegetation put selective pressure on the Hyracotherium, resulting in the changes that were characteristic of the Mesohippus. Coevolution has to involve species that coexist, not species that have a linear evolutionary relationship.

What question did his discovery of horse fossils in South America raise in Darwin's mind?

If horses weren't indigenous to South America, how did the fossils get there? Spanish explorers brought horses to South America because there were no living horses there when they arrived. Darwin knew that the absence of horses indicated that no horses were native to South America within the last few centuries. If no horses were native to South America, then how did the horse fossils get there?

Why is an iridium-rich layer of rock significant in evidence bearing on the Cretaceous-Tertiary extinction?

Iridium is rare on earth but common in extraterrestrial rocks. This fact suggests that the layer of iridium may be extraterrestrial in origin, specifically the result of a meteorite impact. Such an impact would have adversely affected the earth's climate and could have led to the extinction of the dinosaurs.

Of the following choices, the modern horse's most recent ancestor was

Merychippus. Merychippus followed Mesohippus and eventually gave rise to the modern horse. The evolution of the modern-day horse involved several stages. The earliest of these was the small, four-toed Hyracotherium. From this species, the horse progressed to the larger, three-toed Mesohippus, and finally to the hooved Merychippus before evolving into the modern-day horse.

Darwin would explain the evolution of a giraffe's long neck in which of the following ways?

Random mutation produced giraffes with various neck lengths. Longer necks were advantageous to survival, and consequently giraffes with longer necks experienced better reproductive success than giraffes with short necks. Darwin believed that evolution was driven by the "survival of the fittest." The principles underlying this theory were that variations were produced by random processes and that the variations that provided the greatest survival and reproductive advantages would be propagated at a greater rate than variations that were disadvantageous. In this manner, the species would gradually adapt to selective pressures.

Which of the following is not one of the propositions of the theory of evolution by natural selection?

Reproductive potential is limited. According to the theory of evolution by natural selection, every species has the capacity to populate the entire earth. Reproductive potential is not the limiting factor that prevents species from a population explosion. Competition within and between species for limited resources sets the limitation on the number of individuals produced.

Which of the following is an accurate example of the evolution of the horse exhibiting both cladogenesis and coevolution?

Some ancestral horse species got larger and developed an enlarged central toe for walking on the prairie, and this branch of the horse lineage experienced great success as a result of this adaptation. The enlarged central toe is called a hoof, which is an ideal adaptation for a large animal on grassy prairie land.

Which of the statements regarding the Permian time period is incorrect?

The earth was populated by small mammals. The Permian time period was characterized by the formation of a supercontinent called Pangea. During this period, the continent was subject to cold temperature, and giant insects and a variety of reptiles populated the earth. Volcanoes and glaciers were prevalent, and 90% of land and marine species became extinct.

Which of the following findings would have provided Darwin with evidence that evolution by natural selection did not occur?

The fossil evidence shows that species composition always changes suddenly rather than gradually. Evolution is a change in gene frequencies over time. Evolution can occur from mutation, natural selection, nonrandom mating, or genetic drift. In the fossil record, evidence that evolution had occurred by natural selection would be apparent by a gradual shift in species over time. A sudden change in species composition would be interpreted as evolution from one of the other possible mechanisms.

Which of the following is true about fossils?

They can be an imprint of any organism. Fossils can be mineralized bones, plants pressed into shale, insects trapped in resin or other preserved remains or imprints of living beings.

Which statement regarding transition fossils is incorrect?

Transition fossils generally date back to the Precambrian period. Transition fossils do not generally date back to the Precambrian period. During the Precambrian period, organisms were not complex and well developed. The first fossils date back to this period.

Which of the following is evolutionary evidence that whales and dolphins descended from land-dwelling mammals?

Transition fossils show the presence of leglike structures, pointing to the possibility that the ancestors of whale and dolphins once lived on land. Transition fossils show evidence of leglike structures in cetacean ancestors, and these fossils have helped us reconstruct the whale lineage.

While Darwin was on the Galapagos Islands he made some interesting observations regarding giant tortoises. Which one of the following is not a logical question that relates to his theory of evolution by natural selection?

What is the size of the population relative to the amount of available resources? Determining the size of the population relative to the amount of available resources is a question relating to the natural history of the population. Darwin was looking for evidence of evolution by natural history.

An adaptation is

a trait in an organism that helps it survive. An adaptation is any form of a trait that helps an organism survive and reproduce under a given set of environmental conditions.

According to evidence provided by transition fossils, the earliest known birds had all but which of the following characteristics?

absence of teeth The earliest known birds, such as Archaeopteryx and Hesperornis, had long beaklike jaws that were armed with teeth. The presence of teeth was a reptilian condition. The toothless condition seen in modern birds occurred later in evolution.

Natural selection may occur when

all of the above All of the answers contribute to natural selection.

The fossil record represents most completely

all of the above The preservation of organisms as fossils is really against the odds, since fossils have to withstand natural decay processes and environmental stressors. Because of this, not all organisms are represented in the fossil record. The fossil record represents most completely hard-shelled or skeletoned organisms that were abundant, widespread, and that existed over long periods of time.

Many of Charles Darwin's ideas

all of the above. Shortly after his graduation from Cambridge University in 1831, Charles Darwin embarked on a voyage around the world on the HMS Beagle. The observations he made of fossils during this voyage would greatly influence the development of his ideas on evolution. He was also influenced by the theories of gradualism developed by James Hutton and Charles Lyell in the previous century.

The ideas of George de Buffon regarding evolution

all of these. The ideas of George de Buffon were published in the book The Natural History of Animals in the eighteenth century. De Buffon believed that the presence of vestigial organs and homologous structures indicated that species give rise to new species. His work was done in the eighteenth century, approximately 100 years prior to the investigations of Darwin.

Darwin's theory of evolution was lacking

an explanation for the source of variation of traits in a population. Darwin did not know about genes and had no mechanism to explain the variety of traits in a population.

An ecological niche is

an organism's role in its environment. An ecological niche is the sum of all activities and relationships that it needs in order to secure the resources necessary for its survival and reproduction; in other words, it's an organism's role in its environment.

The oldest fossils known are

bacteria. The oldest known fossils were formed by bacterial cells. These fossils date back to the Precambrian period, and are well over 2 billion years ago.

Archaeopteryx is a transition fossil that has characteristics of both

birds and reptiles. Archaeopteryx is a transition fossil that has characteristics of both birds and reptiles. Members of the species had wings and feathers like a bird but also had teeth, claws, and a tail like a reptile.

The taxonomic system developed by Linnaeus

both answer choices A and B are correct. The taxonomic system developed by Linnaeus is a binomial system of nomenclature that classifies species into increasingly broad taxonomic categories.

Absolute dating of fossils

can involve the use of radioactive isotopes. Absolute dating of fossils is a way to determine the actual age of a fossil, rather than simply its age in comparison to other fossils. The primary method of absolute dating utilizes knowledge of the length of the half-lives of radioactive isotopes present in the specimen. Since isotopic half-lives are unaffected by environmental conditions, this form of dating can be very accurate. Another method used to date fossils involves a chemical conversion process called racemization. The degree of racemization that has occurred can also be a precise indicator of age. Racemization can be affected by environmental conditions, however, so its precision is dependent on the climatic consistency of the region in which the fossil was found.

Branching evolution in which one species gives rise to several is referred to as

cladogenesis. Branching evolution in which one species gives rise to several is referred to as cladogenesis.

Carolus Linnaeus

developed a taxonomic system for the identification and classification of species. Carolus Linnaeus developed a taxonomic system for the identification and classification of species in the eighteenth century.

Which of the following is not relevant to Lamarck's theory of evolution?

evolution through random mutation The key components of Lamarck's theory of evolution are use, disuse, and inheritance of acquired characteristics. He did not believe that random mutation played a role in evolution.

True or false? Natural selection is defined as the differential survival and reproduction of a population's individuals that are genetically identical.

false Natural selection is simply the outcome of differences in the survival and reproduction of a populations individuals. These individuals will display variability in one or more traits because of genetic differences. Those individuals with adaptive traits will be more likely to reproduce and their genes will be found in more individuals of the next generation.

True or false? The type and location of rock strata are instrumental in determining the absolute age of a fossil.

false The relative age of a fossil can be determined by the layer of rock in which it is located and the age of other fossils.

Which of the following is not one of the five parts of Darwin's theory of evolution by natural selection?

fitness is determined solely by the ability of an individual to find food By Darwin's theory, fitness is the ability of an individual to reproduce, thus passing traits on to offspring. These traits might include the ability to find food, to find shelter, or simply the ability to better attract a mate.

The binomial system of nomenclature includes the name of the ____________ then the ____________.

genus, species The binomial system of nomenclature is the process by which the species name is defined. The first part of the name is the genus to which the species belongs. The second part of the name is the specific epithet that is associated with the species.

The prevailing theories about mass extinction are that the causes may have been

glacier formation, meteorites crashing into the earth, and movement of continents. The factors that may have contributed to mass extinctions include glacier formation, resulting in a drop in the temperature of the oceans; collisions between the continental landmasses, resulting in a drop in ocean temperatures; and collisions of meteorites into the earth.

Transition fossils provide evidence that cetaceans (whales and dolphins) originated from

land-dwelling mammals. Transition fossils indicate that whales and dolphins evolved from land-dwelling mammals.

The cause of the mass extinctions of marine species at the end of the Ordovician period is thought to be

massive glaciation. The cause of the mass extinctions of marine species at the end of the Ordovician period is thought to be massive glaciation resulting in a drop in the ocean temperatures and levels and the the extinction of ~80% of marine species. Ocean level is thought to have dropped about 50 meters.

Evidence for evolution can also be found in the function and location of various bones in certain species. For example, the reptilian jawbone is composed of several bones, some of which have evolved to become part of the _____________ in mammals.

middle ear The articular and quadrate bones of the reptilian jaw have evolved into the incus and malleus of the middle ear of mammals.

The flying squirrel (genus Glaucomys) and the flying phalanger (genus Petaurus) live on different continents and are only distantly related, yet they share the same

niche. Both the flying squirrel and the flying phalanger are mammals. The two genera are only distantly related; the first belongs to the order Eutheria (the "placental" mammals) and occurs in North America; the second belongs to the order Marsupialia (the "marsupial" mammals) and is native to Australia. Both occupy a similar niche as flying mammals that live and feed in the canopy of trees.

Darwin's theory of natural selection includes the following ideas:

overpopulation, variation of traits in individuals, competition, survival of the fittest, and reproduction. These are the five ideas that explain Darwin's theory of natural selection.

Which of the following was not a characteristic of hyracotherium ?

reptile-like jaw The jaws of hyracotherium were similar to those of modern horses.

Many fossils are formed by __________________, a process in which layers of _______________ settle to form rocks that encapsulate dead organisms.

sedimentation, minerals Many fossils are formed by sedimentation, a process in which layers of minerals settle to form rocks that encapsulate dead organisms. Sedimentation does not occur continuously but in intervals, which causes the formation of rock strata.

While on his voyage, Darwin observed 13 varieties of finches, each with a different niche. Darwin would explain the occurrence by saying that

the different varieties of finches share a common ancestry. According to Darwin, evolution by natural selection can occur as a result of four conditions: (1) members of a species are not identical; (2) the variation in characteristics is heritable; (3) every species has the potential to populate the entire earth; and (4) members of a species differ in their reproductive success. The theory of natural selection suggests that the thirteen varieties of finches all arose from the same ancestral group of finches. Members of the ancestral group were not identical. Some members of the species came to inhabit a particular environment. Over time, traits that were favored in that environment were selected for and increased in frequency; members of the original population branched into thirteen varieties, and each variety became specialized to occupy a particular niche.

Which of the following is not an example of coevolution?

the evolution of reptiles after the evolution of amphibians Reptiles were able to go further onto land, eating plants that had already colonized the interiors of the continents, as well as animals that had followed the plants. They evolved from amphibians, but did not evolve because amphibians had provided them with a new source of food.

Biogeography is

the study of how organisms are distributed around the planet. The study of how organisms are distributed around the planet is called biogeography. Darwin concluded that if the earth can change, the organisms that live on earth can change, too. This idea influenced his formulation of evolutionary theory.

The fossil record tells us that mass extinctions occurred because

there are periods during which there is a sharp decline in the number and types of fossils found. Mass extinctions are always characterized by a sharp decrease in the number of fossils. After this decline, there is a significant change in the types of fossils found.

The significance of the quadruped fossils Darwin found while exploring Argentinean riverbeds was that

they represented species that were extinct. The significance of the quadruped fossils Darwin found while exploring Argentinean riverbeds was that the fossils represented species that were no longer in existence, providing Darwin with evidence that the species composition of the Earth changed over time.

The significance of the fossils of shells that Darwin found in the Cape Verde islands was that

they were found at the top of a cliff. The significance of the shell fossils was that they were found at the top of a cliff. To Darwin, this raised the question of how they had arrived there and whether the cliff had at one point been submerged under an ocean.

True or false? Alfred Wallace proposed a theory of evolution by natural selection.

true Although lesser known than Charles Darwin, Alfred Russel Wallace also proposed a theory of evolution by natural selection.

Selective pressure is

when an outside force affects the composition of a population by favoring certain traits over others. Selective pressure occurs when an outside force, such as predation or prey availability, affects the composition of a population.