Module 3 (The origin of Species)

Question 1

Explain how reproductive barriers would eventually lead to speciation

Answer 1

Reproductive barriers prevent two populations from interbreeding, producing unique species. Instead, groups will keep evolving along separate paths.

Question 1

Summarize key differences between allopatric and sympatric speciation

Answer 1

1. Allopatric speciation occurs if a species is isolated from the parent population. (Other country)
2. Sympatric speciation occurs even without geographic separation. (Same Country)

Question 1

Assess the possible outcomes for hybrids as a result of hybrid zone formation

Answer 1

1.Reinforcement
-hybrids less fit than parents; no gene flow so they decrease overtime.
2. Fusion
-hybrids as fit as parents; substantial gene flow between species
3. Stability
- Extensive gene flow from outside hybrid zone which overwhelm selection.

Question 2

Elaborate on reproductive barriers that block gene flow between the species that eventually limit the formation of hybrids

Answer 2

Pre-zygotic:TEcoBeME
Post-Zygotic: IIB

Question 3

What is the process whereby an ancestral species gives rise to a pair of daughter species?

Answer 3

Speciation

Question 4

What is a group of interbreeding populations that are evolutionarily independent of other populations?

Answer 4

Species

Question 5

Differentiate Microevolution and Macroevolution

Answer 5

Microevolution consists of changes in allele frequency in a population over time

Macroevolution refers to broad patterns of evolutionary change above the species level

Question 6

What does the biological species concept emphasize?

Answer 6

Reproductive Isolation

Question 7

Biological species concept is based on the ___________, not on physical similarity.

Answer 7

potential to interbreed

Question 8

It is the existence of biological factors or barriers that impede members of two species from interbreeding and producing viable, fertile offspring

Answer 8

Reproductive isolation

Question 9

Modified T or F:

Reproduction Isolation PROMOTES gene flow between the species and limit the formation of hybrids

Answer 9

False, blocks

Question 10

What are the Two Types Of Reproductive Barriers?

Answer 10

1. Prezygotic barriers
2. Postzygotic barriers

Question 11

A mechanism that prevents two species from producing viable, fertile offspring thereby preserving the genetic integrity of a biological species

Answer 11

Reproductive barrier

Question 12

What are the five Prezygotic Barries?

Clue: Isolations

Answer 12

1. Temporal
2. Habitat
3. Behavioral
4. Mechanical
5. Gametic

Question 13

What are the three postzygotic Barriers?

Clue: Hybrid

Answer 13

1. Hybrid Inviability
2. Hybrid Sterility
3. Hybrid Breakdown

Question 14

In speciation, Separate populations may evolve independently through three factors. Which are?

Answer 14

1. Mutation
2. Natural Selection
3. Genetic Drift

Question 15

Modified T or F:

SYMPATRIC SPECIATION can result from the appearance of new ecological niche.

Answer 15

True

Question 16

What is the Hybrid Zone?

Answer 16

It is a geographic region where member of different species meet, mate and produce hybrids.

Question 17

What do you call the result of mating between species with incomplete reproductive barriers

Answer 17

Hybrid

Question 18

How long does it take for new species to form? or how many genes needed to differ between species.

Answer 18

Speciation can occur rapidly or slowly and can result from changes in few or many genes

Question 19

In the time course of speciation. Broad patterns in speciation can be studied using what types of record (or data)?

Answer 19

1. Fossil record
2. Molecular record
3. Morphological Record

Question 20

This is the cumulative effect of many speciation and extinction events

Answer 20

Macroevolution

Question 21

What is the evolution of diversely adapted species from a common ancestor upon introduction to new environmental opportunities.

Answer 21

Adaptive Radiation

Question 22

Give an example of Adaptive radiation.

Answer 22

Darwin’s finches