UNIT 7 ck12’s 5.11, 5.15-5.17

Question 1

What is phylogenetic classification?

Answer 1

A method of classifying organisms based on their evolutionary history.

Question 2

Who developed the system of classification based on physical traits?

Answer 2

Linnaeus.

Question 3

What did Linnaeus use as the basis for grouping organisms?

Answer 3

Obvious physical traits.

Question 4

What significant theory did Darwin publish in the 1800s?

Answer 4

The theory of evolution.

Question 5

What is phylogeny?

Answer 5

The evolutionary history of a group of related organisms.

Question 6

How is phylogeny represented visually?

Answer 6

By a phylogenetic tree.

Question 7

What is a clade?

Answer 7

A group of organisms that includes an ancestor and all of its descendants.

Clades are essential for understanding evolutionary relationships among species.

Question 8

What method is used to determine ancestor-descendant relationships?

Answer 8

Cladistics.

Cladistics involves comparing traits in related species.

Question 9

What do clades represent?

Answer 9

They are represented by cladograms.

Cladograms visually depict the relationships among different clades.

Question 10

Which clade includes birds?

Answer 10

The reptile clade.

This indicates that birds evolved from reptiles.

Question 11

Fill in the blank: A _______ is a visual representation of clades.

Answer 11

cladogram.

Cladograms help to illustrate the evolutionary paths of different organisms.

Question 12

How did Linnaeus classify mammals, reptiles, and birds?

Answer 12

In separate classes.

This classification method obscures the evolutionary relationships among these groups.

Question 13

True or False: Cladistics is based solely on physical traits of organisms.

Answer 13

False.

Cladistics also considers genetic data in modern applications.

Question 14

What is the main purpose of fossils in the study of evolution?

Answer 14

Fossils provide clear evidence that evolution has occurred

Fossils serve as a window into the past, revealing the changes in species over time.

Question 15

Who studies fossils?

Answer 15

Paleontologists

Paleontologists are scientists who find and study fossils to understand the history of life on Earth.

Question 16

What significant work did Darwin publish that included evidence for evolution?

Answer 16

On the Origin of Species

In this book, Darwin presented evidence and arguments for the theory of evolution through natural selection.

Question 17

What type of evidence has been gathered since Darwin’s time to support the theory of evolution?

Answer 17

Fossils and detailed knowledge of living things, including their DNA

This additional evidence strengthens the understanding of evolutionary processes.

Question 18

Fill in the blank: The fossil record shows how the _______ evolved.

Answer 18

horse

The evolution of the horse is one example demonstrated through the fossil record.

Question 19

True or False: The fossil record only provides evidence for the evolution of plants.

Answer 19

False

The fossil record provides evidence for the evolution of various species, including animals.

Question 20

What logical arguments did Darwin make in his theory of evolution?

Answer 20

Arguments supporting that evolution occurs by natural selection

Darwin’s arguments were based on observations of variation, inheritance, and survival of the fittest.

Question 21

What size were the earliest horses according to fossils?

Answer 21

About the size of a fox

Question 22

How many toes did the earliest horses have?

Answer 22

Four long toes

Question 23

What type of environment did the earliest horses live in?

Answer 23

Wooded marshlands

Question 24

What did the earliest horses likely eat?

Answer 24

Soft leaves

Question 25

What climate change affected the habitat of horses over time?

Answer 25

The climate became drier

Question 26

What replaced the marshes as the climate changed?

Answer 26

Grasslands

Question 27

How did horses evolve in terms of height?

Answer 27

They became taller

Question 28

Why did taller horses have an advantage?

Answer 28

Helped them see predators while feeding

Question 29

What major evolutionary change occurred to the toes of horses?

Answer 29

Evolved a single large toe that became a hoof

Question 30

What advantage did the hoof provide to horses?

Answer 30

Helped them run swiftly and escape predators

Question 31

What change occurred to the molars of horses?

Answer 31

Became longer and covered with cement

Question 32

What was the purpose of the molars evolving to be longer and covered with cement?

Answer 32

To grind tough grasses and grass seeds without wearing out teeth

Question 33

True or False: Similar fossil evidence shows the evolution of the whale moving from land into the sea.

Answer 33

True

Question 34

What do scientists study to learn about evolution?

Answer 34

Living species ## Footnote Scientists compare anatomy, embryos, and DNA of modern organisms.

Question 35

What is comparative anatomy?

Answer 35

The study of the similarities and differences in the structures of different species.

Question 36

What are the two types of similar body parts in comparative anatomy?

Answer 36

Homologies and analogies.

Question 37

What are homologous structures?

Answer 37

Structures that are similar in related organisms because they were inherited from a common ancestor.

Question 38

Do homologous structures have the same function in descendants?

Answer 38

No, they may or may not have the same function.

Question 39

What is an example of homologous structures?

Answer 39

The hands of several different mammals.

Question 40

What do homologous structures show about evolution?

Answer 40

They provide evidence for evolution by showing common ancestry.

Question 41

What are analogous structures?

Answer 41

Structures that are similar in unrelated organisms due to evolution for the same function, not inherited from a common ancestor.

Question 42

Give an example of analogous structures.

Answer 42

Wings of bats and birds.

Question 43

Why do analogous structures look similar?

Answer 43

Because they evolved to perform the same job.

Question 44

What is a key difference between analogous structures and homologous structures?

Answer 44

Analogous structures evolve independently, while homologous structures are inherited from a common ancestor.

Question 45

Fill in the blank: The wings of bats and birds have the same _______ but evolved independently.

Answer 45

function

Question 46

True or False: Analogous structures are inherited from a common ancestor.

Answer 46

False

Question 47

What can be compared to distinguish between the wings of bats and birds?

Answer 47

The pattern of bones inside the wings.

Question 48

What is comparative embryology?

Answer 48

The study of the similarities and differences in the embryos of different species.

Question 49

What do similarities in embryos indicate?

Answer 49

Evidence of common ancestry.

Question 50

Which structures do all vertebrate embryos have?

Answer 50

Gill slits and tails.

Question 51

What happens to gill slits in most vertebrates by adulthood?

Answer 51

They are lost, except for fish.

Question 52

In humans, what does the tail reduce to?

Answer 52

The tail bone.

Question 53

Why is it valuable to compare organisms in the embryonic stage?

Answer 53

Because similarities may be gone by adulthood.

Question 54

Fill in the blank: Comparative embryology is the study of the _______ and differences in the embryos of different species.

Answer 54

similarities

Question 55

What are vestigial structures?

Answer 55

Structures that have lost most or all of their original function through the course of evolution ## Footnote Examples include the human tail bone and whale pelvis.

Question 56

Give an example of a vestigial structure in humans.

Answer 56

Human appendix ## Footnote It is a remnant of a once-larger organ used for digestion in ancestors.

Question 57

Why do vestigial structures shrink in size?

Answer 57

Because they are no longer used ## Footnote Evolution reduces their size as they serve no significant function.

Question 58

How might a full-sized, unused structure affect an organism's fitness?

Answer 58

It may reduce the organism's fitness ## Footnote Unused structures can consume resources that could be allocated to more beneficial traits.

Question 59

What is biogeography?

Answer 59

The study of how and why plants and animals live where they do.

Question 60

What does biogeography provide evidence for?

Answer 60

Evolution.

Question 61

What is the camel family an example of in biogeography?

Answer 61

The distribution and evolution of species.

Question 62

Where did the ancestors of today's camels live?

Answer 62

North America.

Question 63

How long ago did camel ancestors live in North America?

Answer 63

About a million years ago.

Question 64

Fill in the blank: Biogeography helps explain how _______ and _______ are distributed in different environments.

Answer 64

[plants], [animals]

Question 65

True or False: All of today's camels are descended from different ancestors.

Answer 65

False.

Question 66

List the primary focus areas of biogeography.

Answer 66

* Distribution of species * Evolution of species * Environmental interactions

Question 67

Where did early North American camels migrate to?

Answer 67

East Asia, Africa, South America

Question 68

What land bridge did some camels cross during the last ice age?

Answer 68

A land bridge to East Asia

Question 69

What is the Isthmus of Panama associated with in terms of camel migration?

Answer 69

It is where some camels crossed to reach South America

Question 70

What happened to camels after they reached different places?

Answer 70

They evolved independently

Question 71

What adaptations did camels develop?

Answer 71

Adaptations suited to their particular environments

Question 72

What is the process through which camel descendants evolved their diversity?

Answer 72

Natural selection

Question 73

What does island biogeography provide evidence for?

Answer 73

Evolution

Question 74

What did Darwin study on the Galápagos Islands?

Answer 74

Finches

Question 75

From where did the first finch likely arrive on the Galápagos Islands?

Answer 75

South America

Question 76

What type of eater was the first finch on the Galápagos Islands?

Answer 76

Seed eater

Question 77

What is adaptive radiation?

Answer 77

The process by which a single species evolves into many new species to fill available niches

Question 78

How many finch species evolved from the first finch?

Answer 78

Many

Question 79

What type of evidence do the finches on the Galápagos Islands provide?

Answer 79

Evidence for adaptive radiation

Question 80

Who were the biologists that studied Darwin's finches in the 1970s?

Answer 80

Peter and Rosemary Grant ## Footnote They spent over 30 years on this project.

Question 81

What was the location of the Grants' study on evolution?

Answer 81

Galápagos Islands ## Footnote This is where they re-studied Darwin's finches.

Question 82

What significant event occurred while the Grants were studying the finches?

Answer 82

A drought ## Footnote This event affected the availability of seeds for the finches.

Question 83

What was the impact of the drought on the finch population?

Answer 83

Fewer seeds available for finches to eat ## Footnote This led to a change in survival rates based on beak size.

Question 84

Which type of finch beak had an advantage during the drought?

Answer 84

Bigger beaks ## Footnote Birds with bigger beaks could eat seeds of all sizes.

Question 85

What happened to the small-beaked finches during the drought?

Answer 85

Many died ## Footnote They could only eat smaller seeds, which were less available.

Question 86

What was the result of the survival of birds with bigger beaks?

Answer 86

They survived and reproduced ## Footnote This led to a change in the population's characteristics.

Question 87

What was observed in the finch population within 2 years after the drought?

Answer 87

The average beak size increased ## Footnote This is an example of evolution by natural selection.

Question 88

Fill in the blank: The study of Darwin's finches by the Grants demonstrated _______.

Answer 88

evolution by natural selection

Question 89

True or False: The Grants' research took place over a short period.

Answer 89

False ## Footnote They studied for more than 30 years.