Chapter 21 Evidence of Evolution

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

Pigeons Corn Cats Dogs

What types of species are most likely to be able to disperse to an island (choose all that apply)?

Species that fly Species that float Species that drift

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

climates

Pseudogenes

code for traits no longer present in the phenotype of a species

When two species from different lineages independently evolve similar characteristics because they occupy similar environments, we observe ______.

convergent evolution

A common criticism of evolution is that selection only produces ______ changes and cannot produce the variety of ______ documented in the fossil record.

minor, species

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

Why is it that some organisms do not appear to be perfectly adapted to their environment?

Because natural selection can only work on the variation present in a population.

How does artificial selection contradict the claim that selection can only produce minor evolutionary change?

Differences between breeds can be larger than differences between different genera of animals or plants.

Which of the following are common misconceptions about evolution?

Evolution has not been demonstrated. Complex organs cannot be explained by evolution, but can be explained by intelligent design.

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

Fast runners Long legs Adapted to grasslands

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.

How did Bernard Kettlewell test Tutt's hypothesis about peppered moths?

He released marked dark and light moths in polluted and unpolluted woods and determined their survival.

Which of the following are anatomical features that provide evidence for evolution?

Homologous structures Vestigial structures Early embryonic similarities

Which of the following best distinguishes vestigial from homologous structures?

Homologous structures are functional, while vestigial structures have no function.

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

Homology - Vertebrate forelimbs Embryonic development - Lanugo Vestigial structures - Human coccyx

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

Natural selection

We know that evolution is not a random process, but imagine for a moment that evolution is random. If so, which of the following would be true?

Organisms that are least adapted to their environment could have the highest fitness.

How does the climate drive evolution in the medium ground finch?

The climate impacts the size of seeds, which acts as a selective force for beak size.

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

grasslands

One of the best studied examples of evolutionary change is that of the ____ family. This family includes zebras and donkeys, among other animals.

horse

The primary difference between natural and artificial selection is ______. Multiple choice question.

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

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

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 polluted 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 common misconception among the general public is that the features of species can be scientifically explained by _____ design.

intelligent

Today, fossils have been found that link

all major groups of vertebrates

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

Artificial selection clearly shows that selection ______ evolutionary changes, such that over millions of years, natural selection can produce the diversity of life on Earth.

can produce significant

The ant-eaters in South America and the Australian echidna have similar snouts and tongues that they use to capture ants. This is an example of _______ evolution.

convergent

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

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

Which of the following are reasons why island trees belong to plant families that typically do not have tree members (for example the sunflower family)?

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

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

fossils

_______ are the preserved remains of once living organisms.

fossils

Many fishes that inhabit the sub-freezing Arctic and Antarctic waters posses antifreeze proteins; we now know that there are at least five different kinds of antifreeze protein genes that have evolved independently in different species to perform the same function. This is an example of:

convergent evolution

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

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, light

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

decreases

What type of evidence for evolution is provided by fossils?

direct

Even though there are gaps in the fossil record, some of the most direct evidence for evolution comes from fossils called ______ fossils that illustrate how certain major transformations in life forms occurred.

intermediate, transitional

Some critics of evolution claim that because complex cellular mechanisms (for example, blood clotting) are ______, the intricate machinery of the cell cannot be explained by evolution from simpler stages. But this argument ignores the fact that natural selection operates on ______.

irreducibly complex; a system as a whole

Because it favors those variations that lead to the highest reproductive fitness, natural selection:

is a non-random process

Some species, for example, frogs, are very sensitive to saltwater and therefore have almost no chance of island colonization. Why is saltwater so harmful to these animals?

it causes those animal to dehydrate

Modern members of the horse family have teeth that are _______.

large with a complex pattern of ridges

All modern members of the horse family are large, ____-legged, _____-running animals adapted to living in open _____.

long, fast, grasslands

One of the most successful studies in showing evolution by natural selection is the one done by Peter and Rosemary Grant on the Galápagos islands; these scientists studied a bird that was referred to by the common name of __________ finch.

medium ground

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 foot

Most evolutionary biologists would agree that the primary process responsible for evolution is

natural selection

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

natural selection

Darwin's theory of evolution is

not accepted by everyone in the general public

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

organisms become buried in sediment hard tissue mineralizes surrounding sediment hardens into rock

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

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

pollution

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

silver fox

The teeth of early members of the horse family (for example, Hyracotherium) were ______.

small and relatively simple

What is the preferred food of the Galápagos medium ground finch?

small tender seeds

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, an increase

Fossils include ______.

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

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

streamline, friction

True or false: Natural selection does not always produce perfectly working adaptations, because it can only work on the genetic variation present in a population.

true

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

very rare

A _____ structure has no apparent function in a species, but is fully functional in the species' ancestors.

vestigial

Some species have anatomical features that have no apparent function but resemble structures of their presumed ancestors; these anatomical features are called ______.

vestigial structures

The intelligent design argument cannot explain the presence of

vestigial structures imperfect adaptations

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

Which is a correct statement about the evolutionary changes in the medium ground finch studied by Peter and Rosemary Grant?

Climatic variation impacts seed size, which is a selective force on beak size.

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.

Which of the following is not an example of convergent evolution?

Muscles that wiggle the ears of humans and other mammals

Match the type of rock dating with its description.

Relative dating - Rocks are dated based on their position Absolute dating - Rocks are dated based on changes in their isotopic composition

How has rock and fossil dating changed since Darwin's times?

Relative dating was used in the past; today we use absolute dating.

Which of the following statements about pseudogenes are correct?

They are also known as fossil genes. They are made inactive by mutation.

Which of the following is true about transitional fossils?

They help to fill in the gap in the fossil record between two separate groups. They illustrate how major transitions in life occurred.

What are some fossil findings in recent years that have bridged major gaps in our understanding of vertebrate evolution?

Tiktaalik, a species that is transitional between fish and amphibians. A four legged aquatic mammal that links marine mammals to their terrestrial ancestors. A fossil snake with legs that links modern snakes to the lizards from which they descended.

How has the fossil record changed since Darwin?

Today the fossil record is far more complete.

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.

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

Warbler finches - Small narrow beaks Ground finches - Crushing beaks "Vampire" finches - Sharp beaks

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

artificial

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

artificial

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

artificial selection

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

One of the most important features of Galapagos finches is that the shape of their _____ is related to their _____ habits.

beaks, feeding

Bernard Kettlewell tested Tutt's hypothesis on peppered moths by releasing _______ numbers of dark and light individuals into two sets of woods, and then recapturing and counting the dark and light individuals that ________ in each of the woods.

equal, survive

In all cases when scientists have performed artificial selection experiments on fruit flies, a strong and predictable ________ response has been observed.

evolutionary

In the laboratory setting, selection for a trait in fruit flies ______.

has consistently lead to a strong, predictable evolutionary response

Structures that are derived from a common ancestor but with different appearance and function are called ______ structures, while ______ structures refers to structures that have little or no function but were functional in an ancestor.

homologous, vestigial

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

homologous, vestigial

Two types of structures in adult organisms that provide anatomical evidence for evolution are _____ and _____structures.

homologous, vestigial

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

sediment, mineralizes, hardens

Galapagos finches with powerful thick beaks typically eat large ______.

seeds

According to some critics of evolution, natural selection can produce changes in a population, but it cannot cause substantial changes leading to ______.

the formation of an entirely new species

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

In recent years, scientists have discovered remarkable fossils, such as a four-legged aquatic mammal and a snake with legs. These are examples of ______.

transitional fossils

True or false: Darwin's theory of evolution is not universally accepted.

true