Migration (Lecture 11)

Question 1

Fixation

Answer 1

An allele goes to 100%

Question 2

Mainland/Island Model

Answer 2

Simplest model (Pc to Pi); continent to island

Question 3

Stepping Stone

Answer 3

Multiple populations; migration between geographically adjacent populations

Question 4

Stepping Stone one dimension model

Answer 4

Riverrine model (spot to spot)

Question 5

Stepping Stone 2-Dimension

Answer 5

Patchy grassland; migrating between multiple places; not specific intermediate stops

Question 6

Isolation by distance

Answer 6

Migration between places but not only adjacent habitats

Question 7

Isolation by distance rates

Answer 7

Rates become lower as distance gets larger

Question 8

Mechanisms of gene flow

Answer 8

Any movement of any part of an organism that carry the genes and reproduce in the new environment; depends on organisms life history/biology

Question 9

Example of mechanisms of gene flow

Answer 9

Pollen, adults, juveniles etc.

Question 10

Populations size does not impact the

Answer 10

Number of migrants per generation will prevent differences in populations; all you need is 1 because you need someone to settle drift so that fixation doesn’t occur

Question 11

Homogenization

Answer 11

Makes populations more similar

Question 12

m=

Answer 12

Migration rates

Question 13

Mu=

Answer 13

mutation

Question 14

C=

Answer 14

Continent/mainland

Question 15

0=m(-Pi+Pc)

Answer 15

Equilibrium

Question 16

There are no allele frequency changes when

Answer 16

m=0; no migration; when -Pi=Pc, when island frequency= the continent frequency

Question 17

Migration reduces

Answer 17

Differentiation among populations

Question 18

When migration counteracts natural selection,

Answer 18

An intermediate equilibrium is reached between the two processes

Question 19

Cline

Answer 19

Geographic regions of change in some trait; relatively smooth transition across space

Question 20

Example of Cline graphs

Answer 20

More migration makes a shallower line; Change in Cline slope over time, no differential selection with migration will produce a flat line

Question 21

Ecology and behavior can have profound impacts on

Answer 21

Gene flow and thus evolutionary dynamics

Question 22

Disruption of gene flow is usually a requirement for

Answer 22

speciation