13

Question 1

Mechanisms of speciation?

Answer 1

*Barrier to gene flor between diverging populations.

Question 2

Extrinsic barriers?

Answer 2

Geographical barriers

Question 3

Reproductive barriers (intrinsic)?

Answer 3

Cannot physically mate

Question 4

Allopatric speciation?

Answer 4

When populations are separated by an extrinsic geographic barrier.

Question 5

Peripatric speciation?

Answer 5

Small number of individuals are separated from the main population.

Question 6

Vicariance?

Answer 6

The formation of geographic barriers that separate a population.

Question 7

Parapatric speciation?

Answer 7

When species are spread out over a large geographic area, but mate only with those that live close to them.

Question 8

Sympatric speciation?

Answer 8

If some individuals begin to exploit a new niche, and mate only with others that do the same.

Question 9

Prezygotic barriers?

Answer 9

Occur prior to the fertilization of the egg and the production of the zygote.

Question 10

Prezygotic isolation?

Answer 10

Habitat isolation

Question 11

Pollinator isolation?

Answer 11

Species pollinated by different organisms.

Question 12

Behavioural isolation?

Answer 12

Species utilize a different “mate recognition system”

Question 13

Copulatory behavioural isolation?

Answer 13

During copulation, makes may need to perform behaviours that entice the female into allowing mating to occur.

Question 14

Mechanical isolation.

Answer 14

Species genitalia not compatible.

Question 15

Gametic isolation?

Answer 15

Species gametes not compatible

Question 16

Postzygotic isolation avoids selection for?

Answer 16

hybrids

Question 17

Ecological hybrid inviability?

Answer 17

Hybrids have lower survival in parent habitat

Question 18

Behavioural sterility?

Answer 18

Hybrids can’t obtain mates

Question 19

Primary hybrid zone?

Answer 19

Two separate populations that continue to mate and produce hybrids.

Question 20

Secondary hybrid zone?

Answer 20

Two populations that have been physically separated via allopatric come back together.

Question 21

Reinforcement?

Answer 21

The increase of reproductive isolation between hybridizing populations through selection against hybrid offspring.

Question 22

Selection prefer?

Answer 22

Prezygotic barriers.

Question 23

About how many eukaryote species are known today?

Answer 23

1.9 million

Question 24

How many eukaryotic species do we predict?

Answer 24

5-10 million

Question 25

Phenetic species concept?

Answer 25

Species are defined using morphological traits.

Question 26

Disadvantages to the phenetic species concept?

Answer 26

*Members of the same species can be morphologically distinct
*Cryptic species: morphologically similar but genetically distinct
*Concept relies on human interpretation to define species.

Question 27

Phylogenetic species concept?

Answer 27

Species are the smallest possible groups whose members are descended from a common ancestor and all possess characteristics that distinguish them from other groups.

Question 28

Biological species concept?

Answer 28

Species are a group of actually or potentially interbreeding populations that are reproductively isolated from other groups.

Question 29

Advantages with the biological species concept?

Answer 29

*No trouble with different morphs within a species or cryptic species
*Does not require human interpretation of morphology or detailed phylogenetic information.

Question 30

Disadvantages to the biological species concept?

Answer 30

*What is meant by potentially interbreeding?

*Not useful for ancient species

*Not possible for asexual species

What if populations don’t overlap in the wild but will breed in captivity?

What if they produce offspring but those offspring are infertile or unhealthy?

Question 31

General lineage species concept?

Answer 31

Species are metapopulations that exchange allele frequently enough that they comprise the same gene pool and the same evolutionary lineage. If individuals are in the same gene pool, they are considered the same species.

Question 32

Fused populations?

Answer 32

If divergence in allopatry results in no pre zygotic or post zygotic isolation, and the geographic barrier is removed, ten fusion will result.