Origin of Species

Question 1

Speciation

Answer 1

the process by which one species splits into 2+ species

Question 2

_____ is at the focal point of evolutionary theory.

Answer 2

Speciation

Question 3

Macroevolution

Answer 3

broad patterns of evolutionary change above the species level over long time spans/formations of new groups

Question 4

Biological Species Concept dictates that:

Answer 4

a species is a group of populations whose members have the potential to interbreed in nature and produce viable, fertile offspring

Question 5

The Biological Species Concept places an emphasis on _____ _____.

Answer 5

Reproductive Isolation

Question 6

Reproductive Isolation

Answer 6

impedes two different species from producing viable, fertile offspring

Question 7

Prezygotic Barriers

Answer 7

Block fertilization from occurring

Question 8

Postzygotic Barriers

Answer 8

Reduce survival among hybrid embryos

Question 9

Types of Prezygotic Barriers

Answer 9

• Habitat Isolation
• Temporal Isolation
• Behavioural Isolation
• Mechanical Isolation
• Gametic Isolation

Question 10

Types of Postzygotic Barriers

Answer 10

• Reduced Hybrid Viability
• Reduced Hybrid Fertility
• Hybrid Breakdown

Question 11

Allopatric Speciation

Answer 11

gene flow is interrupted/reduced when a population is divided into geographically isolated sub-populations

Question 12

Sympatric Speciation

Answer 12

Speciation takes place in geographically overlapping populations

Question 13

Allopatric means:

Answer 13

other country

Question 14

What two factors can drive sympatric speciation?

Answer 14

• Habitat Differentiation
• Sexual Selection

Question 15

Polyploidy

Answer 15

Presence of extra sets of chromosomes due to accidents during cell division, resulting from barriers to gene flow

Question 16

Autopolyploid

Answer 16

An individual with 2+ chromosome sets derived from one species

Question 17

Allopolyploid

Answer 17

A species with 2+ chromosomes, derived from a different species

Question 18

Hybrid Zone

Answer 18

A region in which members of different species mate and produce hybrids

Question 19

What are the three possible outcomes when closely related species meet in a hybrid zone?

Answer 19

1. Reinforcement
2. Fusion
3. Stability

Question 20

Reinforcement

Answer 20

Strengthening of reproductive barriers that occurs when hybrids are less fit than parent species

Question 21

Fusion

Answer 21

Weakening of reproductive barriers that occurs if hybrids are as fit as parents; parent and hybrid species will fuse into one if gene flow is great enough

Question 22

Stability

Answer 22

The continued formation of hybrid individuals that occurs when hybrids have increased fitness relative to the parent species

Question 23

In the reinforcement of reproductive barriers, ______ species will be preferred to _____ species.

Answer 23

Allopatric; Sympatric

Question 24

The fusion of the parent and hybrid species, if ____ ____ is great enough.

Answer 24

gene flow

Question 25

Habitat Isolation

Answer 25

Differences in where species live, preventing them from encountering one another

Question 26

Temporal Isolation

Answer 26

Difference in species-specific mating cycles, causing mating to be unlikely

Question 27

Behavioural Isolation

Answer 27

Distinct differences in courtship behaviours/traditions that aren't noticed/recognized by females of different species

Question 28

Mechanical Isolation

Answer 28

Physical differences in genitalia preventing successful mating

Question 29

Gametic Isolation

Answer 29

When sperm and egg of different species cannot fuse to form a zygote

Question 30

Reduced Hybrid Viability

Answer 30

Resulting hybrid embryos often do not survive or will have major morphological anomalies that cause them to die off.

Question 31

Reduced Hybrid Fertility

Answer 31

Hybrid offspring will often be sterile/infertile

Question 32

Hybrid Breakdown

Answer 32

occurs when first generation of hybrid offspring are viable and fertile, but when they mate, their offspring are inviable/infertile