10: mating systems

Question 1

what 4 things are included in a mating system classification?

Answer 1

• copulation behaviour
• social organisation
• parental care system
• competition for mates

Question 2

list the 4 mating systems

Answer 2

• monogamy
• polygyny
• polyandry
• polygynandry

Question 3

what do social mating systems not always reflect and give an example

Answer 3

the genetic mating system

extra pair paternity in birds

Question 4

what is monogamy and give 4 examples and which group are mainly monogamous

Answer 4

1 male and 1 female
birds
- swan 
- clownfish
- fulmar
- splendid fairy wren

Question 5

roughly what % of birds are socially monogamous and what % are also genetically monogamous?

Answer 5

90%

<25%

Question 6

• what is polygyny
• what group is it mostly
• what are the 2 types and an example for each

Answer 6

• 1 male and >1 female
• mammals
• simultaneous: red winged blackbird
  successive/sequential: orangutan

Question 7

• what is polyandry
• what are the 2 types and an example for each
• what can often happen in this mating system?

Answer 7

• 1 female and >1 male
• simultaneous: painted snipe
  successive/sequential: spotted sandpiper
• sex role reversal

Question 8

• what is polygynandry
• what groups are mainly included
• give 2 examples

Answer 8

• > 1 female and >1 male
• reptiles, fish, amphibians
• guppy and foam nest tree frog

Question 9

mating systems often vary within a species, list 3 examples

Answer 9

• extra pair paternity in monogamous species
• dunnocks
• humans

Question 10

what mating systems do dunnocks engage in and in what proportions?

Answer 10

• 1/3 monogamy
• 1/4 polygyny
• 40-50% polyandry or polygynandry

Question 11

what is the reproductive potential for males and females like and what they are limited by

Answer 11

males > females

• males limited by access to females
• females limited by access to resources

Question 12

what should males do to maximise their fitness?

Answer 12

directly monopolise lots of females or monopolise resources she needs for survival and reproduction

Question 13

what determines the mating system?

Answer 13

female and male dispersion

Question 14

what is the general model?

what does It predict?

Answer 14

ecology/resource distribution > female dispersion > male dispersion
- predicts that mating systems should reflect female dispersion and resource distribution

Question 15

what is resource defence polygyny and an example?

Answer 15

• males defend key resources wanted by females

tent making bats- males construct and defend roosting tents that house harems of females with 1M: 1-37F

Question 16

in mammals male parental care is rare so what does female monopolisation by males and mating system depend on?

Answer 16

• female group size

- female range size for travel

Question 17

in Clutton Brock 1989 study what was discovered for when females are solitary and the range is defendable? (3)

Answer 17

• 60% mammals
• small range: polygyny, voles and otters
• large range: monogamy, gibbon

Question 18

in Clutton Brock 1989 study what was discovered for when females are solitary and the range is not defendable? (3)

Answer 18

• scramble competition
• polygyny
• orangutan cant defend the widely distributed rainforest patches

Question 19

in Clutton Brock 1989 study what was discovered for when females are social and the range is defendable? (2)

Answer 19

• small group: uni male polygyny, colobus

- large group: multi male polygyny, lion

Question 20

in Clutton Brock 1989 study what was discovered for when females are social and the range is large and not defendable? (3)

Answer 20

• large unstable groups
• males may aggregate in leks when high competition for females
• Uganda kob
• Topi

Question 21

list the two example experiments to answer the question: do resources determine female dispersion and in turn male dispersion?

Answer 21

• blue headed wrasse

- grey sided vole

Question 22

blue headed wrasse all start off as female and become males at a certain size- what is the difference between the males and females? - 2 for each

Answer 22

females
- forage over large overlapping ranges
- spawn daily at favoured sites 
males 
- cant defend females 
- compete for and defend spawning sites on reefs

Question 23

what was warner 1990 experiment on blue headed wrasse (5)

Answer 23

• removed males and replaced with new ones
• when males removed 22/24 sites still used and no new sites, would follow what previous males did
• removed females and replaced with new ones
• when females removed 11 sites lost and 10 new spawning sites found
• females determine the site of spawning and males compete to defend those sites

Question 24

what was experiment 1 for the grey sided vole? (3)

Answer 24

• small patches rich with food
• food distribution determines female distribution
• males also followed

Question 25

what was experiment 2 for the grey sided vole? (3)

Answer 25

- captive females and radio tracked males - males would collapse their range around the females - female dispersion determines male dispersion

Question 26

what was experiment 3 for the grey sided vole? (3)

Answer 26

- captive males and radio tracked females | - no effect of male dispersion on female dispersion

Question 27

the reproductive potential of males is not always realised so what does this mean for the mating systems and their reproductive success?

Answer 27

sexual conflict over them | more variation

Question 28

how can females maximise their reproductive success?

Answer 28

monopolise parental care from males

Question 29

where is sexual conflict over mating systems common?

Answer 29

in birds

Question 30

what type of mating system does the male and female prefer?

Answer 30

male: polygyny female: polyandry so can get more or better resources such as parental care

Question 31

in many species why does monogamy often occur?(3)

Answer 31

- at a compromise between conflicting interests of the sexes - males may be unable to defend more than 1 female at a time - female may force monogamy upon male

Question 32

what is the yellow bellied marmot example for sexual conflict over mating systems? (2)

Answer 32

- females raise more offspring in smaller groups and get more parental care - male overall gains more offspring in a large harem

Question 33

what is the female enforced monogamy in burying beetle example for sexual conflict over mating systems? (3)

Answer 33

- female and male make a nest with a corpse and care for offspring - males attempt to attract extra females using pheromones - females try to prevent males form doing so

Question 34

give 5 points summarising mating systems

Answer 34

- very variable - potential reproductive rate drives variation - ecological factors set the scene for mating system evolution - experiments support general model - sexual conflict plays a key role in mating system evolution