Lecture 10: mating strategies

Question 1

mating systems classification encompasses:

Answer 1

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

Question 2

monogamy

Answer 2

1M and 1F

most birds, a few mammals and fish

Question 3

__% of socially monogamous birds are also genetically monogamous

Answer 3

<25%

Question 4

polygyny =

Answer 4

1 m and >1 F

-few birds, most mammals

Question 5

2 forms of polygyny

Answer 5

• simultaneous (red-winged blackbird)

- successive/sequential (orangutan)

Question 6

polyandry;

Answer 6

1 female and >1 male

-few birds, fish and mammals

Question 7

2 forms of polyandry

Answer 7

• successive/sequential (spotted sandpiper)

- simultaneous (painted snipe)

Question 8

promiscuity

Answer 8

polygynandry

• > 1 females and 1> male
• few birds, few mammals, many fish, reptiles and amphibians

Question 9

do mating systems vary within a species?

Answer 9

YES,
dunnocks and extra pair paternity in monogamous species (adelies penguins)
humans

Question 10

who has a greater reproductive potential M/F?>

Answer 10

MALES

Question 11

reproductive potential: Males are limited by

Answer 11

access to females

Question 12

reproductive potential: females are limited by

Answer 12

access to resources

Question 13

General model of mating systems

Answer 13

ecology –> female dispersion –> male dispersion

resource defence links ecology and male dispersion

Question 14

resource defence polygyny =

Answer 14

males defend key resources wanted by females
-e.g. tent making bats
–> males construct and defend roosting test which house harems of females
sex ration: 1M:1-37F

Question 15

Clutton-Brock 1989

Answer 15

• supports general model, leks?
• in mammals, male parental care is rare
• female monopolisation by males and hence mating system depends on :
• -female groups size
• -female range size

Question 16

female solitary: range defendable

Answer 16

• 60% of mammal species
• small range –> polygyny
• large range –> monogamy

Question 17

female solitary: range not defendable

Answer 17

scramble competition polygyny

Question 18

female social: range defendable:

Answer 18

• small groups = uni-male polygyny

- large groups = multi-male polygyny

Question 19

female social: large range not defendable

Answer 19

large unstable groups, males may aggregate in leks when competition for females is intense

Question 20

lek polygyny

Answer 20

ecological basis for lek formation applies across taxa

Question 21

experimental evidence that resources determines female dispersion which, in turn, determines male dispersion?

Answer 21

• Blue-headed wrasse (Thalassoma bifasciatum) Warner 1990

- Grey-sided vole

Question 22

Warner 1990 blue-headed wrasse

Answer 22

females = forage over large overlapping ranges, spawn daily at predictable, favoured sites
Males = can’t defend females, compete for and defend spawning sites
-spawning sites –> female dispersion –> male dispersion

Question 23

Grey sided vole experiment

Answer 23

1) female range encompassed by male range, food added in 2 separate sites, 2 new female ranges, males also converge to these sites
2) captive females, radio tracked males, so female dispersion determines male dispersion
3) revers exp. 2, captive males, radio tracked females, no effect of M dispersion on F dispersion

Question 24

reproductive potential of males is not always

Answer 24

realised

Question 25

when M provide parental care we see a ____ in reproductive potential

Answer 25

reduction

Question 26

males ‘___’ polygyny

Answer 26

prefer

Question 27

females may ‘prefer’ polyandry if they get

Answer 27

better/more resources (e.g. parental care)

Question 28

in many species, monogamy occurs as a

Answer 28

compromise between coflidting interests of the sexes

Question 29

sexual conflict over mating system: yellow-bellied marmot

Answer 29

females raise more offspring in small groups

• males raise more offspring in large groups
• compromise

Question 30

sexual conflict over mating system: Female enforced monogamy in burying beetles

Answer 30

female & male make a nest containing a corpse, and then care for offspring
-males attempt to attract additional F, F try to prevent them doing so

Question 31

potential reproductive rates of sexes drives

Answer 31

variation