T10

Question 1

sexual selection

Answer 1

selection for characters that increase the mating success and increases the ability to sexually reproduce

Question 2

viability selection

Answer 2

selection acting on variability in characters that increase survival (avoiding predation/foraging)

Question 3

natural selection with sexual and viability

Answer 3

natural selection encompasses these two different selections which often act against eachother
- eg peacock tail
- the bigger the peacock tail the increase in sexual selection, however, causing a downfall for viability as more obvious to predators

Question 4

intrasexual selections

Answer 4

active competition amongst one sex to get a mate
- because of anisogamy

Question 5

intersexual selection

Answer 5

based on interactions between the sexes
- affecting courtship behaviours k

Question 6

malr and female reproductive success

Answer 6

male success - limited by the number of females he mates with

female success- limited by the number and quality of her offspring

Question 7

cyclical parthenogenesis

Answer 7

cycles for sexual and sexual phases
- when environment is fine, asexual phases
- when the environment is harsh, asexual females produce sexual m+f rather than other asexual
- sexual m+f reproduce to form diploid resting eggs which wait in pond sediment until environment improves

Question 8

reproductive strageries when intrasexual competition occuring

Answer 8

used to maximise reproductive success when there is intrasexual competition

Question 9

harem defense

Answer 9

M v M
- the males fight to dominate groups of females
- evolved when females are distributed into defendable groups

Question 10

territory defense

Answer 10

males defend spawning sites as females need to visit to lay eggs
maximise reproductive success as males can then mate with females present that are fertile as they are at spawning sites

the bigger the territory the more females for males to mate with, increasing their reproductive sucess

Question 11

sperm competition

Answer 11

bigger testes more sperm produced so greater chance at fertilising egg

females have many partners during a cycle so increases competition

Question 12

extra pair copulations

Answer 12

when there is monogamous species, the male still cares for female it is with but will also go off and father other offspring to increase reproductive success

Question 13

sneaky males

Answer 13

hover around terriorties that are guarder and try to sneak in and fertilise females rather than trying to find own terriority

Question 14

female mimics

Answer 14

morphologically look like females so are welcomed into a territory and can fertilise eggs that way

Question 15

reasons for such differences

Answer 15

individuals can recognise if they will succeed being a territory holder or not so will adapt and find another path to reproduce if not

Question 16

intersexual reproductive strageries - male courtship

Answer 16

aim is to look as attractive to female as possible
the male that is most attractive has a greater reproductive success
this is instead of fighting

Question 17

intersexual reproductive strageries female courtship

Answer 17

females need to be picky as need to increase her own reproductive success
choose a male
- that can provide best resources to feed offspring
- best genetic material, biggest, most attractive

Question 18

intersexual reproductive strageries - sex role reversal

Answer 18

where males invest more than females, roles can reverse, eg with seahorse

Question 19

problems with sex

Answer 19

direct costs of sex
- energy spent finding a mate, defending and attracting, high energy taxing

genetic cost
- recombination load, making genes

cost of males - only in isogamous species

Question 20

cost of males

Question 21

benefits of sex

Answer 21

sex allows a parent to produce offspring genetically better than they are
1. bringing together beneficial genes
2. rid of bad mutations

the allele for sex spread quickly as it is associated with increasing fitness

Question 22

evolving sexual species

Answer 22

because of the benefits sex has, sexual species evolve much faster than asexual as they can adapt faster so are less likely to go extinct