Evidence of Evolution

Question 1

Fossils are when…

Answer 1

Dead organisms sometimes leave traces of their existence

Question 2

What is most likely to be fossilized?

Answer 2

Hard body parts like shells, bones, and teeth

Question 3

Why are not all organisms represented in the fossil record?

Answer 3

Only a fraction of those formed are ever found

Question 4

What do we use to determine the age of fossils?

Answer 4

Relative dating

Question 5

How can we make the transitions between fossils apparent?

Answer 5

By placing them in chronological order

Question 6

What is the Law of Superposition?

Answer 6

Sedimentary layers are deposited in a time sequence, oldest on bottom and youngest on top

Question 7

How is it possible to reconstruct the sequence of geologic events that have occurred at a site?

Answer 7

Using relative dating principles and the position of layers within a rock

Question 8

What does a transitional fossil show?

Answer 8

The change from one species to another

Question 9

What is comparative embryology?

Answer 9

The comparison of embryos at different stages in the development of different organisms

Question 10

What do similarities in embryonic development suggest?

Answer 10

Common ancestry

Question 11

What does oviparity mean?

Answer 11

Birds, frogs, and most invertebrates give birth to eggs instead of live young

Question 12

What does viviparity mean?

Answer 12

Eutherian mammals give birth to live young instead of eggs

Question 13

What does ovoviviparity mean?

Answer 13

Certain reptiles and sharks produce an egg that hatches inside the body

Question 14

Describe the holoblastic pattern of cleavage

Answer 14

The entire egg is divided into smaller cells in frogs and mammals

Question 15

Describe the meroblastic form of cleavage

Answer 15

Chicks where only one part of the egg is destined to become the embryo while the other part serves as nutrition

Question 16

In 1651, William Harvey concluded that all animals, even mammals, originate from…

Answer 16

Eggs, Ex ovo omnia (all from the egg)

Question 17

What is the blastoderm of a chick embryo?

Answer 17

The small region of the egg that contains yolk-free cytoplasm that gives rise to the embryo

Question 18

What did William Harvey discover in the blastoderm of a chick embryo?

Answer 18

Islands of blood cells form before the heart does

Question 19

What type of structure are pharyngeal pouches?

Answer 19

Homologous

Question 20

What does comparative embryology show?

Answer 20

How different adult structures of many animals have the same embryonic precursors

Question 21

Explain homologous structures

Answer 21

Result from a common ancestor, even if they look different today

Question 22

What is an example of a homologous structure

Answer 22

Bat wing and human hand (share all of the same bones)

Question 23

Homologous structures are an example of…

Answer 23

Divergent evolution

Question 24

When does divergent evolution occur?

Answer 24

When two or more biological characteristics have a common evolutionary origin but have diverged over time

Question 25

Divergent evolution is also known as…

Answer 25

Adaption or adaptive evolution

Question 26

Homologous structures can be either…

Answer 26

Observable or molecular such as genes

Question 27

Explain analogous structures

Answer 27

Features that do NOT share a common ancestor, but may have the same function (opposite of homologous)

Question 28

What is an example of an analogous structure?

Answer 28

Bird wing and bat wing, evolved independently

Question 29

Analogous structures are an example of…

Answer 29

Convergent evolution

Question 30

What is convergent evolution?

Answer 30

The process where organisms not closely related independently evolve similar traits as a result of adapting to similar environments/niches

Question 31

What are vestigial structures?

Answer 31

Homologous characters which have lost all or most of their original function through evolution

Question 32

Vestigial structures may…

Answer 32

Take various forms such as anatomical structures, behaviors, and biochemical parhways

Question 33

Some vestigial structures disappear in _________ ___________, but others are ________ in _________

Answer 33

Embryonic development, retained, adulthood

Question 34

List characteristics of vestigial structures

Answer 34

Have no purpose Leftovers from ancestors that needed them

Question 35

List examples of vestigial structures

Answer 35

Wings in flightless birds Leg bones in whales and snakes Human body hair Appendix

Question 36

What animal has a fossil record with transitional species?

Answer 36

Horses

Question 37

Plant and animal cells…

Answer 37

Share most of the same organelles

Question 38

The closer two organisms are related, the more _____ they have in common and the closer their _____ ____ _________ are

Answer 38

Genes, amino acid sequences

Question 39

Some genes are…

Answer 39

Widespread among organisms

Question 40

What does the pax-6 gene contain?

Answer 40

The instructions for making the eye in humans and flies

Question 41

Examples of suboptimal design

Answer 41

Trachea vs Esophagus (can lead to choking) Human eye (inverted retina; blind spot) Non-coding DNA

Question 42

Sympatric speciation occurs when…

Answer 42

Populations of a species that share the same habitat become reproductively isolated from each other

Question 43

Allopatric speciation (most common) occurs when…

Answer 43

Populations of a species become geographically isolated and become genetically different over time

Question 44

Describe Parapatric speciation

Answer 44

Extremely rare, occurs when populations are separated by extreme change in habitat (not geographical barrier) and may develop distinct characteristics and lifestyles

Question 45

What type of crops/livestock are chosen to reproduce?

Answer 45

Most fit/desirable