Test 2

Question 1

Polymorphism

Answer 1

Simultaneous occurrence of two or more discontinuous phenotypes (or genes) in a population

Question 2

Balanced Polymorphism

Answer 2

Selection maintains more than or equal to two alleles at relatively high frequencies for many generations

Question 3

Transient polymorphisms

Answer 3

Temporary response to selective pressure

Question 4

Geographic polymorphism

Answer 4

Isolation yields different morphs

Question 5

Heterozygosity

Answer 5

Illustrates how much of a species total genetic diversity (Ht) is due to genetic variability WITHIN populations (Hs) versus AMONG populations (Dst)

Question 6

Heterozygosity and Fitness

Answer 6

Fitness = contribution of an individuals genotype to the gene pool of the next generation, relative unit of pressure

• high heterozygosity may result in greater fitness in cases where over dominance of heterozygote (sickle cell anemia) exceeds fitness of either homozygote

Question 7

3 Types of Islands

Answer 7

1. Temporary
2. Continental
3. Oceanic

Question 8

Primary Factors Controlling Island Colonization (5)

Answer 8

1. Island size
2. Island latitude
   3 Island topography
3. Distance to mainland source
   5 Disturbance Regime (hurricanes, etc)

Question 9

Ecological Release (?)

Answer 9

The absence of competition and / or predation island species expand into a greater variety of habitats compared to closed related mainland species

Question 10

Density Compensation

Answer 10

Compared with nonspecific mainland populations, species on oceanic island exhibit relatively greater densities

Question 11

Dwarfism (?)

Answer 11

Large animals get smaller

Question 12

Gigantism (?)

Answer 12

Small animals get bigger

Question 13

Rescue Effect

Answer 13

Reduction in extinction rate of near island versus distant ones

Question 14

Target Effect

Answer 14

Increase in immigration rate in large islands versus small ones

Question 15

Metapopulations

Answer 15

• balance between extinction rates in occupied patches and colonization rate of empty patches

Ex: Christmas Tree; some lights are on, while others are off, and they alternate

Question 16

Sources

Answer 16

Habitat patches where local survival is MORE than local mortality

Question 17

Sinks

Answer 17

Habitat patches where local survival is LESS than local mortality

Question 18

Extinction

Answer 18

Constant risk multiplied by the number of occupied patches

Question 19

Colonization

Answer 19

Dependent on number of occupied (sources) and empty (target) patches

Question 20

Turnover ***

Answer 20

Extinction of local populations and establishment of new local populations in empty habitat patches by migrants from existing local populations

Question 21

Types of Fragmentation (5)

Answer 21

1. Perforation
2. Dissection
3. Fragmentation
4. Shrinkage
5. Attrition

Question 22

Responses to Habitat Fragmentation (4)

Answer 22

1. Initial Exclusion
2. Isolation
3. Island-Area Effects
4. Edge Effects

Question 23

1. Initial Exclusion

Answer 23

Many species eliminated given remaining fragments represent only a sample of the original habitats

Question 24

2. Isolation

Answer 24

Modified landscape restricts movement and dispersal

Question 25

3. Island - Area Effects

Answer 25

Fragments include fewer habitats, smalls populations more susceptible to local extinction events

Question 26

4. Edge Effects

Answer 26

Climactic influence and environmental degradation results in increased predation and competitors, reduced area of suitable core habitat

Question 27

Corridors (5)

Answer 27

1. Environmental 2. Introduced 3. Disturbance 4. Remnant 5. Regenerated

Question 28

Corridor Functions (5)

Answer 28

1. Habitat 2. Conduit 3. Filter / Barrier 4. Sink 5. Source