Biology exam 1 review

as the horse family fossil record became more complete, scientists realized that the evolution of horses was not linear, constant, and unidirectional. Why?

Change often occurred simultaneously across the different lineages of the horse family the rates of evolution varied through time with long periods of little or no change In some lineages completely opposite trends are observed

The forelimbs of vertebrates are an example of _____ structures, while the human appendix is an example of a _____ structure.

Homologous vestigial

The fossil record reveals that during the last 25 million years most of the lineages in the horse family have exhibited a rapid and substantial _____ in size.

Increase

Over the last 55 million years, the limbs of animals in most lineages of the horse family have ______ in length.

Increased

what is the current explanation, from an evolutionary standpoint, of the lack of large placental mammals in Australia?

Placental mammals evolved elsewhere and could not disperse to Australia due to its isolated position in the ocean.

which of the following accurately describes sperm competition?

a female mates with multiple males and not e very male's sperm has equal chances of fertilizing an egg.

The odd proportions of dachshunds have resulted from

artificial selection for dogs that could enter narrow badger holes

in _____ selection, humans choose the parents of the next generation, while in _____ selection, organisms that survive and reproduce are those that pass their genes on.

artificial, natural

when did humans begin to utilize artificial selection?

centuries and millennia ago

Overall, the evolutionary changes observed in the fossil record of the horse family can be understood as adaptations to changes in global _______

climate

when a female mates with multiple males, not every male's sperm has an equal chance to fertilize an egg; in these cases, we observe sperm ______ between males

competition

sexual selection is a type of natural selection in which the evolution of certain traits is driven by which of the following types of competition?

competition for mates

structures that have evolved separately but look very similar exhibit______ evolution; in contrast, structures that evolved through modification from a common ancestral trait are ______ structures.

convergent, homologous

One of the best studied examples of evolutionary change is that of the _____ family. this family includes zebras and donkey, among other animals

equidae

Which of the following are common misconceptions about evolution that were traditionally thought to be revealed by the fossil records of horses.

evolutionary change is constant through time natural selection is a progressive guiding force pushing evolution in a single direction

which of the following is true of evolutionary forces in natural populations?

evolutionary forces can alter allele frequencies in natural populations

True or false: artificial selection has only recently become possible because of advances in our knowledge of genetics

false

true or false. recent findings suggest that there is no correlation between the prevalence of dark forms of moths and the pollution levels in an area.

false

true or false: even though humans have used artificial selection for centuries, only animals have been significantly modified by our efforts

false

____ are the preserved remains of once living organisms

fossils

_____ are the preserved remains of once living organisms

fossils

which of the following is the most direct evidence for evolution?

fossils

what genetic phenomena may be responsible for unintentional selection?

gene linkage pleiotropy

different alleles of genes are found within different individuals of a population. This is known as.....

genetic variation

which of the following best describes the genetic variation of a population?

genetic variation refers to the fact that different individuals of a population have different alleles of genes.

Evolutionary changes in the horse family can be related to changes in their habitat in North America (where most of the horse evolution occurred); in particular, horse evolution was related to the widespread appearance of

grasslands

artificial selection has resulted in all of the following outcomes in agriculture except

higher susceptibility to disease in tomatoes.

Structures with different appearances and functions that are all derived from the same body part in a common ancestor are called ______ structures

homologous

evolutionary biologist believe that even though they serve different functions, the forelimb of a frog and the forelimb of a bat share structural similarities and are derived from a common ancestor. This makes these forelimbs an example of ______

homologous structures

Match the different types of anatomical evidence for evolution to an example

homology-vertebrate forelimbs embryonic development- lanugo Vestigial structures- human coccyx

The primary difference between natural and artificial selection is

how the parents are chosen (by humans or because of their reproductive success)

starting in 1850 when Europe become industrialized, the frequency of melanic forms of the peppered moth in populations _______ until they made up _____ of some population

increased; almost 100%

in certain areas of the world, populations of moths have been shown to change over the years with dark forms becoming more abundant than light forms; this phenomenon is called

industrial melanism

the phenomenon, where dark forms of moths become more prevalent than light forms in industrialized areas, is known as ________

industrial melanism

A type of sexual selection in which members of one sex, usually females, choose mates based on particular characteristics such as courtship songs is called ________

intersexual selection

______ selection is a form of sexual selection based on same-sex competition usually involving males, in which the winner "gains" a mating partner

intrasexual

in _______ selection, a small number of males may mate an inordinate number of times, while a large number of males rarely mate, if they mate at all

intrasexual

The teeth of modern members of the horse family are

large with a complex pattern of ridges

In ______ mammals the young are born in a very immature condition and held in a pouch; in contrast, the offspring of ______ mammals are not born until they can safely survive the external environment.

marsupial, placental

which of the following provide evidence that natural selection occurs in peppered moths?

melanic moths become more abundant than light forms in polluted areas light moths become more abundant than melanic forms when clean air legislation is implemented

The observation that the relative frequencies of melanic to light peppered moths changes with the color of tree bark provides support for _____

natural selection

The primary process responsible for evolution is ________

natural selection

review the following list of processes that can alter the genetic make up of a population. Which one is considered by scientist to be primarily responsible for evolution?

natural selection

which of the following statements about intrasexual selection is true?

often a few successful males may engage in an inordinate number of matings, while most males do not mate at all.

The _____ content of corn kernels have been increased dramatically by over 90 generations of ____ selection.

oil, artificial

The feet of modern horses have ____ toe(s); in contrast, early horses had _____ toe(s) on their front feet and ______ toe(s) on their hind feet.

one four three

features that increase the chance that a mate will be chosen by a female are known as ________ characteristics

secondary sexual

A deer's antlers, a ram's horns and the bright plumage of a male paradise bird are all examples of which of the following?

secondary sexual characteristics

Rock fossils are created when three event occur; dead organisms are buried in _____; hard tissues ______; the material that surrounds the remains ______ hardens to form rock.

sediment mineralize hardens

_____ selection is a type of natural selection in which competition for mates drives the evolution of certain traits

sexual

In many species of animals, males and females look very different as a result of sexual selection. These animal species exhibit which of the following?

sexual dimorphism

sexual selection favors traits that give males greater ability in mate competition, therefore males and females within the same species may exhibit different traits. This difference between the sexes of the same species is known as

sexual dimorphism

after generations of selective breeding, this animal has been made exceptionally tame.

silver fox

Fast swimming marine predators such as dolphins, sharks, and tuna have a _____ body shape that minimizes ______ in the water.

similar, resistance

The teeth of early members of the horse family were?

small and relatively simple

The fossil record shows that early species of horses were generally ______ in size, but many lineages since about 30 million years ago exhibit substantial change toward _____ in size.

small; and increase

Fossils include

specimens in amber specimens preserved in dry caves Specimens preserved in permafrost remains preserved in rocks

attempts to domesticate silver foxes by artificial selection resulted in the _____ selection of traits which produced silver foxes that were as tame as domestic dogs

unintentional

Prior to 1850, the melanic form of the peppered moth in Europe was:

very rare

match the beak shapes of Galapagos finches to their feeding habits.

warbler finches-small narrow beaks ground finches- crushing beaks "vampire" finches- sharp beaks

The evolution of members of the horse family is

well documented by the fossil record

The short legs and broad feet of early horses made them well adapted to their habitat which was

wooded areas

developmental patterns seen in a group of organisms often reveal evolutionary relationships. Place the developmental descriptions in the order that they would occur in a group or related organisms, beginning with the earliest description at the top.

1. greatest similarity is present 2. different characteristics are lost or formed 3. final form is attained

Place the series of events that must occur to produce a rock fossil in order, starting at the top.

1. organisms become buried in sediments 2. Hard tissues (such as bones) mineralize 3. Surrounding sediment hardens into rock

in artificial selection experiments with corn plants that began in the 19th century, scientists have managed to increase oil content of corn kernels by

450%

which of the following are potential direct benefits of mate choice?

A male that provides the best parental care increases the chances of rearing more offspring a male that has a better territory can provide higher quality food for females.

what type of evidence for evolution is provided by fossils?

Direct

Which of the following statements about marsupials in Australia is true?

For many types of placental mammals found throughout the world, there is a strikingly similar marsupial mammal in Australia.

Which of the following are typical characteristics of all modern members of the horse family?

Long legs fast runners adapted to grasslands

early horses had four toes on the front feet and three toes on the hind feet, all encased in fleshy pads. what statement correctly describes how the toes have changed during the evolution of modern horses?

Modern horses have a single toe enclosed in a bony hoof

an opossum gives birth to tiny young that finish developing in the mother's pouch. A whale sustains its developing offspring in the uterus. Which of the following correctly identifies the opossum and whale?

The opossum is marsupial, whale is placental

The great variety of breeds of cats, dogs and other domestic animals have arisen through

artificial selection

In many animals, structures used for fighting, such as horns, have evolved to be larger in males because of which of the following?

They confer an advantage in intrasexual competition

which of the following is not a direct benefit of mate choice?

a healthier male is less likely to cary disease

today, fossils have been found that link

all major groups of vertebrates

Genetic variation in a population results from evolutionary forces that cause changes in....

allele frequencies

Most of the species that humans use as food have been modified through _____ selection

artificial

one of the most important features of Galapagos finches is that the shape of their _______ is related to their ______ habits

beaks, eating

Early horses inhabited woody areas where they probably browsed leaves and escaped predators by dodging through openings; this explains why those animals had _____ feet and _____ legs.

broad, short

regarding the peppered moth, many studies have shown that in polluted areas, the _____ form of the moth is favored by natural selection, and in unpolluted areas, the _____ form of the moth is favored.

dark (melanic): light (peppered)

scientists have observed that when air pollution is significantly reduced, the frequency of the melanic form of peppered moths

decreases

artificial selection may result in traits that are

desirable, unintended, intended, undesirable

In many animals, selection has favored traits that confer greater ability in mate competition; as a result of such selection, one of the sexes- usually males- can look very different. This is known as sexual________

dimorphism

varieties of which of the following organisms are the result of artificial selection?

dogs, pigeons, corn, cats

Organisms that are believed to share a common ancestor often show similarities in their early ______ development before diverging into varied forms

embryonic

what kinds of mammals were found on Australia when it separated from the rest of the continents?

only marsupial mammals

economically important organisms that have been modified significantly through artificial selection include

pigs, cattle, corn

as a result of convergent evolution, many marsupial mammals of Australia look similar to _______ mammals found elsewhere and occupy a similar ecological niche.

placental

unintentional selection can be the result of linkage and

pleiotrophy

scientist have observed that light colored moths decrease in abundance in areas that are _____

polluted

scientists have observed that light colored moths decrease in abundance in areas that are ______

polluted

The frequency of melanic peppered moths has decreased in areas where _______ is removed from the air and environment

pollution

Which of the following are reasons why island trees belong to plant families that typically do not have tree members?

the tree niche is empty and so a flower can evolve through natural selection to be tree-like tree seeds rarely make it to isolated islands

What trend has been observed in the fossil record of horses regarding the length of their limbs

they have generally increased in length

most of the species that we use as food do not look like their ancestral species anymore. How have humans achieved that?

through artificial selection

how are traits produced by convergent evolution different from homologies

traits produced by convergent evolution have not evolved from a common ancestral trait, while homologies have