Bio chapter 21B

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

Fast runners Long legs Adapted to grasslands

--- evolution happens when two species from different lineages independently evolve similar characteristics because they occupy similar environments.

convergent

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

The similar shapes of fast swimming marine predators are an example of --- evolution.

convergent

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

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

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

convergent evolution

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

homologous

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 vestigal

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 vestigal

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

The forelimbs of modern vertebrates exemplify

homologous structures

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.

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

intelligent

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 hardens

Molecular analysis of lactase DNA --- in humans shows that genes for that enzyme have --- evolved in Africa and Europe to produce the same result.

sequences independently

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

streamlined friction

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.

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 bone) mineralize 3. surrounding sediment hardens into rock

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 attained

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.

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

Early embryonic similarities Homologous structures Vestigial structures

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 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 is the most direct evidence for evolution?

Fossils

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

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

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

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.

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.

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

Muscles that wiggle the ears of humans and other mammals

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

Natural selection is a progressive guiding force pushing evolution in a single direction. Evolutionary change is constant through time.

Why is the argument "proteins are too improbable" invalid?

Probability cannot be used to argue backwards

`Why is the argument "proteins are too improbable" invalid?

Probability cannot be used to argue backwards

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.

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

Species that drift Species that fly Species that float

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

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

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)?

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

Which of the following is true about transitional fossils (choose all that apply)?

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

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.

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

True

Today, fossils have been found that link

all major groups of vertebrates

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

The forelimbs of modern vertebrates are homologous structures, meaning that they may have changed evolutionarily to perform different functions, but they

evolved from the same body part in a common ancestor.

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.

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

horse

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

inaccessible

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

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

island

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

long fast grasslands

Darwin's theory of evolution is

not accepted by everyone in the general public

When considering that Earth is an --- system, it is easy to see that evolutionary theory does not violate the second law of thermodynamics.

open

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

placental

Fossils that contain characteristics of two separate groups of organisms are called --- fossils.

transitional

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. Select all that apply.

transitional intermediate

ven 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. Select all that apply.

transitional intermediate