Chapter 17- Speciation

Question 0

Biological Species Concept

Answer 0

Based on reproduction

Question 1

Morphological Species Concept

Answer 1

Based on appearance alone (phenotype). But is not reliable due to the subtle variations that are displayed

Question 2

Species

Answer 2

One or more populations of individuals that are interbreeding under natural conditions and producing fertile offspring and are reproductively isolated from other such populations

Question 3

Genetic changes between populations can only be encountered by what?

Answer 3

Gene Flow

Question 4

Genetic Divergence

Answer 4

Differences build up between the gene pools of genetically separate populations

Question 5

Reproductive Isolating Mechanisms

Answer 5

Any heritable feature of body, form, functioning, or behavior that prevents breeding between one or more genetically divergent populations

Question 6

Pre-Zygotic Isolation

Answer 6

Mating or zygote formation is blocked

Question 7

List the 5 types of Pre-Zygotic Isolations

Answer 7

1. Temporal Isolation
2. Behavioral Isolation
3. Mechanical Isolation
4. Ecological Isolation
5. Gamete Mortality

Question 8

Temporal Isolation

Answer 8

Different groups may not be reproductively mature at the same month, year, or season.

Question 9

Behavioral Isolation

Answer 9

Patterns of courtship may be altered to an extent that sexual union is not achieved

Question 10

Mechanical Isolation

Answer 10

Differences in reproductive organs prevent successful breeding

Question 11

Ecological Isolation

Answer 11

Potential mates may be in the same general area but not in the same habitat where they are likely to meet

Question 12

Gamete Mortality

Answer 12

Incompatibilities between egg and sperm prevent fertilization

Question 13

Post-Zygotic Isolation

Answer 13

Occurs after members of two different species have mated and produced a hybrid offspring

Question 14

Zygotic Mortality

Answer 14

Egg is fertilized but zygote or embryo dies

Question 15

Hybrid Inviability

Answer 15

First generation hybrid forms but shows low fitness

Question 16

Hybrid Infertility

Answer 16

Hybrid is fully or partially sterile

Question 17

Allopatric Speciation

Answer 17

Physical barrier prevents gene flow between populations of a species

Question 18

Sympatric Speciation

Answer 18

New species forms within a home range in the absence of physical barrier

Question 19

Parapatric Speciation

Answer 19

Neighboring populations become distinct species. Hybrid Zone, daughter species formed by a common geographical border

Question 20

Cladogenesis

Answer 20

Lineage splits resulting in genetic isolation and branching of species

Question 21

Background Extinction

Answer 21

Local changing conditions

Question 22

Mass Extinction

Answer 22

Catastrophic global event

Ex. Temperature changes, asteroids