Origin of Species (Ch. 24)

Question 1

8 types of hybrid barriers

Answer 1

1. Habitat Isolation
2. Temporal Isolation
3. Behavioral Isolation
4. Mechanical Isolation
5. Gametic Isolation
6. Reduced Hybrid Viability
7. Reduces Hybrid Fertility
8. Hybrid Breakdown

Question 2

Species Definition

Answer 2

Group of populations whose members have the potential to interbreed in nature and produce viable offspring.

Question 3

Allopolyploidy

Answer 3

An individual with more than 2 sets of chromosomes derived from a DIFFERENT species.

Question 4

Autopolyploidy

Answer 4

An individual with more than 2 sets of chromosomes derived from the SAME species.

Question 5

Allopatric Speciation

Answer 5

Gene flow is interrupted or reduced when a population is divided into geographically isolated subpopulations.

Question 6

Sympatric Speciation

Answer 6

Speciation takes place in geographically overlapping populations.

Question 7

Speciation

Answer 7

The evolutionary process by which populations evolve to become distinct species.

Question 8

Hybrid Zone

Answer 8

A region in which members if different species can mate and produce hybrids.

Question 9

3 Possible Outcomes for Hybrid Zones

Answer 9

1. Reinforcement: Strengthening reproductive barrier, offspring is less fit.
2. Fustion: Weakening reproductive barrier, offspring are as fit as parents.
3. Stability: Continued formationf of hybrid individuals.

Question 10

Other Definitions of Species

Answer 10

1. Morphological Species Concept: Structural features
2. Ecological Species Concept: Ecological niche
3. Phylogenetic Species Concept: smallest group of individuals on a phylogenetic tree.

Question 11

Eldredge and Gould

Answer 11

Punctuated Equilibrium.