Module 14 - Evolution

Question 1

What is natural selection?

Answer 1

Theory of evolution developed by Darwin, the survival of the fittest.

Question 2

Who was Charles Darwin?

Answer 2

Scientist who developed the theory of evolution and natural selection.

Question 3

Who was Thomas Malthus?

Answer 3

An economist who introduced the idea of natural selection in terms of humans.

Question 4

What are the four principles of natural selection? *

Answer 4

Excess reproduction (producing way more seeds than can actually be sustained)

Variations (differences in traits between a group of organisms)

Inheritance (organisms get traits from their parents)

The advantages of specific traits in an environment (organisms with the best traits will survive longer, reproduce, and eventually that trait will be the main one in that species)

Question 5

What is evolution?

Answer 5

The change in species over time

Question 6

What is a derived trait? *

Answer 6

A new feature that had not appeared in common ancestors

Question 7

What is an ancestral trait? *

Answer 7

More primitive characteristic that appeared in common ancestors

Question 8

What is an embryo?

Answer 8

An early, pre-birth stage of an organism’s development

Question 9

What is a homologous structure? *

Answer 9

Anatomical structures inherited from a common ancestor

Question 10

What are vestigial structures? *

Answer 10

A kind of homologous structure that has either a reduced function or no function in an adult organism. They are functional in related organisms or were functional in an ancestor.

Question 11

What is an analogous structures? *

Answer 11

Structures that can be used for the same purpose and can be superficially similar in construction, but are not inherited from a common ancestor

Question 12

What is geographic distribution?

Answer 12

The idea that organisms are more similar to other organisms in their area than organisms across the planet, suggesting that the plants and/or animals in a geographic location share a closer ancestor than plants and/or animals in a different part of the Earth.

Question 13

What is biogeography?

Answer 13

The study of the distribution of plants and animals around the world

Question 14

What are the five categories that offer evidence for evolution? *

Answer 14

The fossil record, comparative anatomy, comparative embryology, comparative biochemistry, and geographic distribution

Question 15

What is fitness?

Answer 15

A measure of the relative contribution that an individual trait makes to the next generation

Question 16

What is the difference between camouflage and mimicry?

Answer 16

Camouflage makes an organism difficult for predators to see by blending in with their environment. Mimicry is an adaptation where one species starts to look like another, more harmful species so that predators are less likely to attack them.

Question 17

What is the Hardy-Weinberg principle? *

Answer 17

When allelic frequencies remain constant, a population is in genetic equilibrium. (proportions of genotypes)

Question 18

What five conditions does a population need to meet to be in genetic equilibrium? *

Answer 18

No genetic drift
No gene flow (no immigration or emigration)
No mutation
Mating must be random
No natural selection

Question 19

What is genetic drift?

Answer 19

Random change in allelic frequencies in a population

Question 20

What is the founder effect?

Answer 20

Random effect that can occur when a small population settles in an area separated from the rest of the population and interbreeds, producing unique allelic variations. (changing the allelic frequencies.)

Question 21

What is a bottleneck?

Answer 21

Process in which a large population declines in number, then rebounds. (changing the allelic frequencies)

Question 22

What is stabilizing selection *

Answer 22

Most common form of natural selection in which organisms with extreme expressions of a trait are removed. (against both extremes)

Question 23

What is directional selection? *

Answer 23

Shift of a population toward an extreme version of a beneficial trait. (against one extreme, towards the other)

Question 24

What is disruptive selection? *

Answer 24

Process in which individuals with average traits are removed, creating two populations with extreme traits. (Against the mean)

Question 25

What is sexual selection?

Answer 25

Change in frequency of a trait based on the ability to attract a mate

Question 26

What are the three types of natural selection?

Answer 26

Stabilizing selection
Directional selection
Disruptive selection

Question 27

What is the difference between prezygotic and postzygotic?

Answer 27

Prezygotic is before fertilization and postzygotic is after fertilization.

Question 28

What are prezygotic isolating mechanisms?

Answer 28

Mechanisms that prevent genotypes from entering a population’s gene pool, by making fertilization unlikely through geographic, ecological, or behavioral differences.

Question 29

What are postzygotic isolating mechanisms?

Answer 29

Mechanisms that prevent survival or reproduction in hybrid offspring.

Question 30

What are the two types of speciation?

Answer 30

Allopatric and sympatric

Question 31

What is the difference between allopatric speciation and sympatric speciation? *

Answer 31

Allopatric speciation is when a species becomes multiple species because of a physical barrier, while sympatric speciation happens without a physical barrier.

Question 32

What is adaptive radiation?

Answer 32

(aka divergent evolution) Can occur in a relatively short time when one species gives rise to many species in response to the creation of a new habitat or another ecological opportunity

Question 33

What is coevolution?

Answer 33

When the evolution of one species affects the evolution of other species (such as mutualism or coevolutionary arms race)

Question 34

What is convergent evolution? *

Answer 34

Unrelated species evolve similar traits even though they live in different parts of the world.

Question 35

What is the theory of gradualism?

Answer 35

Evolution happens in small, gradual steps.

Question 36

What is the theory of punctuated equilibrium?

Answer 36

Tries to explain the abrupt transitions in the fossil record. Rapid spurts of genetic change cause species to diverge quickly and then have longer periods with little change.