Week 2 Genetic Dridt

Question 1

What is natural selection?

Answer 1

→ considered the main evolutionary mechanism
→depends on genetic drift and gene flow

Question 2

What is sampling error?

Answer 2

Random bias that occurs when sample sizes are small

Question 3

What is the definition of a species?

Answer 3

Group of populations who’s members have the same
Potential to interbreed in nature to make fertile offspring
→ there are many definitions
→humans commonly identify organisms based on how they look

Question 4

Reproductive isolation

Answer 4

Pre-zygotic and post-zygotic isolation

Question 5

Define pre-zygotic mechanisms

Answer 5

Preventing the formation of a zygote

Question 6

Define post-zygotic isolation

Answer 6

Impairing survival or reproduction of the zygote

Question 7

What are the three phases of speciation

Answer 7

1. Separation
2. divergence
   3.reproductive isolation

Question 8

What is separation

Answer 8

Gene pools that separate into smaller groups that are isolated from gene flow

Question 9

Define divergence

Answer 9

Groups of species diverging

Question 10

What is allopathic speciation?

Answer 10

Closely related species have geological or physical separation

Question 11

How does sexual selection drive reproductive isolation

Answer 11

→sexual selection involves rapid evolutionary changes

Question 12

Define polyploidy

Answer 12

Genetic change causing instant reproductive isolation between gene pools

Question 13

Define cline

Answer 13

Change in allele frequency across hybrid zone
→ provides evidence of substantial genetic exchange

Question 14

What are the outcomes of hybridization?

Answer 14

1. Hybrid zones are stable
2. Reinforcement for reproduction

Question 15

What is speciation?

Answer 15

Evolutionary process in which one species splits into 2 or more
→ Darwin realized that it explains why organisms share traits

Question 16

Define microevolution

Answer 16

Changes over time in allele frequencies

Question 17

Define macroevolution

Answer 17

Broad pattern of evolution above species level

Question 18

What is the biological species concept

Answer 18

Species are groups of populations in which members can reproduce

Question 19

How do prezogtic barriers block fertilization?

Answer 19

1. Impeding members of a diff species
2. Prevent successful mating
3. Hindering fertilization

Question 20

What is the morphological species concept

Answer 20

Characterizes a species in terms of body shape/other structure

Question 21

What is the ecological species concept

Answer 21

Views species in terms of ecological niche, sum of how members of the species interact with the non-living parts of their environment

Question 22

What is an allopolyploid?

Answer 22

Bertie when mating with each other but cannot interbreed

Question 23

What is a hybrid zone?

Answer 23

Place where members of different species meet and mate

Question 24

What are the main stages of life?

Answer 24

1.abiotic (non-living)
2. Small molecules
3. Packing into proto-cells
4. Origin of self replicating molecules

Question 25

What is radio metric dating?

Answer 25

Method for determine age based on half-life of radioactive isotopes

Question 26

What are the eons?

Answer 26

1. Archaeon
2. Proterozoic
3. Phanerozoic

Question 27

What are the eras?

Answer 27

1. Paleozoic
2. Mesozoic
3. Cenozoic

Question 28

Define stromatolites

Answer 28

Layers rocks that formed when prokaryotes bind thin films together

Question 29

What does serial endosymbiosis mean?

Answer 29

Hypothesis predicts that mitochondria evolved before plastids through endusymbiotic events

Question 30

What is adaptive radiation

Answer 30

Period of evolutionary change in which groups of organisms form new species with successful adaptations

Question 31

What is heterochrony?

Answer 31

Evolutionary change in the timing or rate of an organisms development

Question 32

Define paedomorphosis

Answer 32

Retention in an adult organism of juvenile features of its evolutionary ancestors