Lecture 5: Adaptation and Evolution

Question 1

what is evolution

Answer 1

A process that changes populations of organisms over time.

Question 2

How dose evolution occur?

Answer 2

Through changes in gene frequency over time, within a population

Question 3

What are the two required components for evolution?

Answer 3

Evolution requires Phenotype variation among individuals that is heritable

Question 4

What are Genetic Differences?

Answer 4

Variation as a result of differences in genome

Question 5

What is Phenotypic Plasticity?

Answer 5

Variation as a result of environmental influences

Question 6

What is a phenotype?

Answer 6

An attribute of an organism such as its behavior, morphology, or physiology.

Question 7

What is a genotype?

Answer 7

The set of genes an organism carries

Question 8

What is genetic drift?

Answer 8

Extremely important in smaller populations,

it is where Random processes result in the loss of genetic variation in mating, fecundity, mortality, inheritance

Question 9

What is a Genetic bottle neck?

Answer 9

A reduction in genetic diversity in a population due to a large reduction in population size.

Question 10

What is the founders effect?

Answer 10

When a small number of individuals leave a large population to colonize a new area and bring with them only a small amount of genetic variety.

Question 11

What is natural selection?

Answer 11

The differential reproduction and survival of individuals in a population due to environmental influences

Question 12

What is the first rule of natural selection?

Answer 12

There are many more offspring produced than can be supported by the environment (competition)

Question 13

What is the second rule of natural selection?

Answer 13

Traits vary among individuals within a population and may be heritable

Question 14

What is the overall basis of natural selection?

Answer 14

Some heritable traits give individuals an advantage in the environment.

Such as advantageous traits, conferring higher fitness.

All of these traits will slowly become more common.

Question 15

What are adaptations?

Answer 15

Traits that have been selected for through natural selection

Question 16

What is directional selection?

Answer 16

When the mean population shifts from one direction to another through some animals showing advantageous adaptations

Question 17

What is stabilizing selection?

Answer 17

Selection that sees the average population having the favorable trait (mean in the center)

Question 18

What is disruptive selection?

Answer 18

Selection that spits a population in half, with the center mean being the smallest population.

Question 19

What is a Species?

Biological species concept

Answer 19

Group of actually or potentially interbreeding population, which are reproductive isolated from such groups”

Question 20

What is Speciation?

Answer 20

Physical and ecological processes interact with selection and random processes such as drift to produce species.

Question 21

True or false:

Morphology is best way to identify species.

Answer 21

True

Question 22

What is the biological species concept?

Answer 22

The idea that organisms that can interbreed are members of the same species.

Question 23

What are the two major forms of reproductive isolation?

Answer 23

Prezygotic
&
Postzygotic

Question 24

What are some examples of Prezygotic reproductive barriers?

4

Answer 24

• The inability to find a mate (Ecological)
• The organisms not being fertile at the same time (temporal)
• Give & recivie mating cues (behavioral)
• the parts cannot go together ( mechanical)

Question 25

What are examples of postzygotic reproductive barriers?

Answer 25

• the Zygote & embryotic development is impossible (Hybrid inviability)
• Production of grandchildren is impossible (hybrid sterility)

Question 26

What is Allopatric specication?

Answer 26

• Barrier creates geographically isolated populations

Question 27

What is Parapatrc speciation?

Answer 27

Population expands into new habitat within range of parent species

Question 28

What is sympatric speciiation?

Answer 28

Genetically distinct populations form within barrier or spatial isolation.

Question 29

What causes Sympatric spceiation?

Answer 29

Disruptive selection leading to associative mating