Week 4

Question 1

Pros to sexual reproduction

Answer 1

-male parental care
-sexual selection removes bad alleles
-recombination

Question 2

Cons to sexual reproduction

Answer 2

-Have to make males(2 fold cost)
-may disrupt advantageous combinations of alleles
-could be risky (predation, STDS)

Question 3

Advantages of having separate sexes

Answer 3

-allows purging of deleterious alleles
-exploit a complex fitness landscape
-decreases inbreeding

Question 4

Female choice

Answer 4

females may choose mates on the basis of
-physical characteristics
-resources or parental care

Question 5

What are the causes of sexual selection

Answer 5

female choice, male-male competition, innate biases and sensory exploitation

Question 6

Honest advertising

Answer 6

attractive physical feature that directly translates to increased fitness

Question 7

Nuptial gifts

Answer 7

anything a male provides to incise a female to mate with them
ex: sexual cannibalism

Question 8

What does sexual selection in males being higher than in females cause

Answer 8

higher variation in reproductive success in males vs females, but still produce same amount of offspring on average

Question 9

Sensory exploitation

Answer 9

preexisting bias before the evolution of that feature

Question 10

Speciation

Answer 10

occurs when populations accumulate genetic differences that cause reproductive incompatibilities

Question 11

The biological species concept

Answer 11

assigns individuals to the same species if they actually or potentially interbreed

Question 12

What is the problem with the BSC

Answer 12

the concept is difficult to apply to natural systems

Question 13

Examples of Prezygotic isolation

Answer 13

temporal, habitat, behavioral, gametic barrier, mechanical

Question 14

Examples of Postzygotic isolation

Answer 14

hybrid viability and hybrid sterility

Question 15

Temporal isolation

Answer 15

populations are isolated because they breed at different times

Question 16

habitat isolation

Answer 16

populations are isolated because they breed in different habitats

Question 17

behavioral isolation

Answer 17

populations do not interbreed because their courtship displays differ

Question 18

Gametic barrier

Answer 18

Matings fail because eggs and sperm are incompatible

Question 19

Mechanical isolation

Answer 19

Matings fail because male and female genitalia are incompatible

Question 20

Partial postzygotic isolation

Answer 20

when one gender of a hybrid is sterile and the other is fertile

Question 21

Hybrid viability

Answer 21

hybrid offspring do not develop normally and die as embryos

Question 22

hybrid sterility

Answer 22

hybrid offspring mature but are sterile as adults

Question 23

The Morphospecies Concept

Answer 23

species are distinguished by differences in size shape or other morphological features
-rather subjective

Question 24

The phylogenetic species Concept

Answer 24

Based on reconstructing the evolutionary history of populations
Species is defined as the smallest monophyletic group on a tree that compares populations
-tends to over diagnose specise

Question 25

Allopatric Speciation by dispersal

Answer 25

The physical barrier pre-dates the time of speciation

Question 26

Allopatric speciation by vicariance

Answer 26

the physical barrier causes speciation and therefore is approximately the same age

Question 27

Geographical distance as a reproduction barrier

Answer 27

allele frequencies are initially evenly distributed and then later become unevenly distributed due to geographical distance