ch.20

What is the current explanation, from an evolutionary standpoint, of the lack of large placental mammals in Australia? Multiple choice question.

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

Which of the following statements about adaptations that evolved through natural selection is true?

Some organisms do not appear to be perfectly adapted to their environment.

in ______ selection, humans choose the parents of the next generations, while in _______ selection, organisms that survive and reproduce are those that pass their genes on

artificial natural

Darwin's finches represent a ______ that is thought to have evolved from ______ that diversified in an environment with many available niches and different selective pressures.

cluster of species; an ancestral species

_________ evolution happens when natural selection appears to have favored parallel adaptations in unrelated organisms that live in similar environments.

convergent

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

convergent evolution

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

corn cats pigeons dogs

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

false

Despite the presence of many dinosaurian traits, Archaeopteryx fossils possess ______, which are a definitive trait of birds.

feathers

Organisms that are transitional between hoofed mammals and whales, between reptiles and mammals, between apes and humans, and between fish and tetrapods are all examples of ______ that have been discovered.

fossil intermediates

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

fossils

Research in which the ______ of different vertebrates were compared showed that ______ genetic differences are present in vertebrates that are more closely related.

genomes less

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

has consistently lead to a strong, predictable evolutionary response

Artificial selection has resulted in all of the following outcomes in agriculture except ____.

higher susceptibility to disease in tomatoes

Evolutionary biologists 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.

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

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

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

minor species

For an island, dispersal from a nearby continent is usually ________ likely than dispersal from more distant sources

more

relative dating ----> absolute dating ----->

rocks are dated based on their position rocks are dated based on changes in their isotopic competition

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 mineralize harden

'' Features of fruit flies that have been selected for in laboratory experiments include body ______, eye _____, and growth rate, among others

size color

What is the magnitude of change produced by artificial selection?

substantial

Even though it has feathers similar to modern birds, Archaeopteryx also has many features of carnivorous dinosaurs, for example, _______ in its mouth and a bony ______

teeth tail

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.

Because changes in traits are due to changes in alleles of a gene, the more distantly related two organisms are,

the more different they are molecularly.

Select all of the following in which a streamlined body shape for fast swimming has evolved due to convergent evolution.

tuna dolphins ichthyosaurs sharks

Presumably, when the ancestor of the Galapagos finches arrived on the islands, many of the bird niches were ______, such that the finches could move into them, and then under differing selective pressures, the finches evolved into separate ______.

vacant, species

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

vestigal

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 medium ground finch of the Galápagos islands feeds on small seeds, produced in abundance during _____ years

wet

Why is evolution considered a theory?

- Because it is supported by a large body of evidence. - Because it helps explain a very wide range of observations.

Select all of the following that provide molecular evidence of evolution.

- Color vision genes are similar among relatives of humans. - All animals possess similar pattern formation genes.

Select the biogeographical observations about islands made by Darwin during his voyage around the world.

- Island species are usually most closely related to species on nearby continents. - Islands are often missing plants and animals that are common on continents. - Island species have often diverged from their continental relatives.

Which of the following are reasons why the fossil record is incomplete?

- Many fossils occur in rocks that are inaccessible. - Organisms decay or are scavenged before forming fossils. - Fossils can be destroyed before they are collected.

Select the conditions that scientists must demonstrate are occurring in studies of natural selection in action.

- There must be variation in the population for the trait being examined. - The variation must be genetically transmissible. - The variation must lead to differences among individuals that affect reproductive success.

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

Supporters of intelligent design cannot explain the presence of

- imperfect adaptations - vestigal structures

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

- pigs - corn - cattle

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 of 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 attached

Experiments with fruit flies have shown that significant evolutionary change can be observed within

35-40 generations

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

450%

What similar selective pressures have resulted in convergent evolution of streamlined body shape in sharks, tunas, and dolphins?

Advantages of swimming fast as marine predators

Which of the following would be molecular evidence of evolution?

Conserved DNA sequences

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.

Finches on the Galapagos islands exhibit remarkable variation in the shape of their beaks. What best explains this variation?

Differences in their feeding habits

Select all of the following organism transitions that are documented by the fossil record.

Fish and tetrapods Hoofed mammals and whales Dinosaurs and birds

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.

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 animals to dehydrate.

After 20 generations of artificial selection, what happened to the average time for onset of tooth decay in laboratory rats?

It increased from 100 days to over 500 days.

Why are giraffe necks not perfectly suited for their function?

Like all mammals, giraffes only have 7 vertebrae in their necks which limits their flexibility.

Typically, how are species on islands related to species on a nearby continent?

More closely

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 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 describes the process of relative dating used to estimate the age of rocks and fossils in the nineteenth century?

Rocks are dated by their relative position, rocks in deeper strata being generally older.

What types of species are most likely to be able to disperse to an island?

Species that float Species that fly Species that drift

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.

Which of the following is not an example of an imperfect adaptation?

The human coccyx

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, the whale is placental

How has the fossil record changed since Darwin?

Today the fossil record is far more complete.

Today's geologists are able to use ______ to establish the age of rocks based on amount of decay of a radioactive isotope.

absolute dating

Galápagos finches supposedly underwent a(n) ______ after an ancestral population arrived on the islands about 2 million years ago and eventually evolved into a cluster of 14 species with different feeding adaptations.

adaptive radiation

The phenomenon in which a cluster of species evolves to occupy several different niches within a region is called

adaptive radiation.

Today, fossils have been found that link ____.

all major groups of vertebrates

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

artificial

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

beak food

_________ is the study of the geographic distribution of modern and extinct species.

biogeography

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

can produce significant

Genetic changes in ______ accumulate at a constant rate, such that the pattern can be referred to as a molecular clock.

cytochrome c

In absolute dating of rocks, the age of rocks around a fossil can be determined by measuring the amount of

decay of radioactive isotopes.

Laboratory selection experiments have produced forms that cannot reproduce and thus would in nature be considered

different species

What type of evidence for evolution is provided by fossils?

direct

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

embryonic

When fossils are arranged and compared according to their age, from oldest to youngest, successive _______ change becomes apparent

evolutionary

Contrary to the claims by supporters of intelligent design, the fossil record shows that many complex features of species such as the bones in the mammalian ear have

evolved incrementally.

True or false: All organisms have become perfectly adapted to their environment in the course of evolution.

f

True or false: Organisms that are more closely related have accumulated a greater number of genetic changes.

f

The primary difference between natural and artificial selection is

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

fruit fly =

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

One reason why the fossil record is incomplete is that many fossils occur in rocks that are _______ to scientists

inaccessible

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

is a non random orocess

Evolution by natural selection requires that variation exists for a trait, the variation in the trait leads to differential reproductive success, and that the variation

is heritable

Darwin noted that _____ communities are often missing plants and animals typically found on continents

island

The significant changes illustrated by artificial selection provide strong support for the power of _____ selection

natural

Darwin's theory of evolution is

not accepted by everyone in the general public

lesser anteater -----> flying squirrel ------> wolf------>

numbat flying phalanger thylacine

the _______ content of corn kernels has increased dramatically since 1896 as a result of over 90 generations of _______ selection

oil artificial

when considered that earth is a

open

In a classic experiment, scientists selected for fruit flies with many bristles on their abdomen by

picking out and breeding the 20% of the population that had the greatest number of bristles.

how often do fossils form

rarely

Geologists of the nineteenth century were able to use ______ to get a fairly accurate idea of the age of rocks using their positions in the strata and known rates of erosion.

relative dating

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.

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