Birds
Week 7
Mating and Social Behavior
Mating systems; nature of the pairing between the sexes
- Most species monogamous [90%]
- M invest in reproduction
o EG: Australian Malleefowl; related to chickens// build mounds at 4yr but more
attractive the bigger they get [30yrs] // M guard eggs [round 3m, 1m high nest,
control temp by adding or removing sand]
o EG: Red necked Phalarope; F larger and brightly colours/ M incubate and rear
chicks while F reproduce again
1. Monogamy;
- M attempt to fertilize large number of F
- High potential for parental care [EG. Snow bunting = more offspring fledge when M
present]
- Pair bonds; one breeding season, variable times
o Long lived birds [Geese/swans/albatrosses/ herring gulls/ ravens] = mate for
life to save on investment in courtship.
2. Polygyny:
- Resource defense, patchy and defended by M [nesting habitat with limited resources =
better nest sites = resources = mates]
o Trade-off: resources and parental care [F access to food but less help rearing]
o EG: RW Blackbird [North America]; sexually dimorphic [F brown], M have
<10 F
- Female Defense;
o EG: Montezuma oropendola; M fight to control clusters of breeding F // F
build nests in isolated clumps// M = dominance hierarchies [alpha = >90%]
Limiting factor = nest sites.
- Leks;
o Small display sights without useful nest sites/ food.
o Communal [black grouse/ruff] or solitary [bower birds/pheasants]
o M bright, F duller// noisy displays// M dominate mating.
a. Hot Spot model; M gather in high density of F
b. Hot shot model; M gather round dominant experienced M
c. Female preference model; F to compare M directly
3. Cooperative Courtship;
a. Direct benefit; gain some mating anyway
b. Indirect benefit; helps relatives [inclusive fitness]
c. Delayed direct benefit; inherit patch
4. Polyandry;
- F with multiple mates [Spine and Jacana/ Dunnock]
Courtship and Display;
1. Ritualized Displays;
Week 7
Mating and Social Behavior
Mating systems; nature of the pairing between the sexes
- Most species monogamous [90%]
- M invest in reproduction
o EG: Australian Malleefowl; related to chickens// build mounds at 4yr but more
attractive the bigger they get [30yrs] // M guard eggs [round 3m, 1m high nest,
control temp by adding or removing sand]
o EG: Red necked Phalarope; F larger and brightly colours/ M incubate and rear
chicks while F reproduce again
1. Monogamy;
- M attempt to fertilize large number of F
- High potential for parental care [EG. Snow bunting = more offspring fledge when M
present]
- Pair bonds; one breeding season, variable times
o Long lived birds [Geese/swans/albatrosses/ herring gulls/ ravens] = mate for
life to save on investment in courtship.
2. Polygyny:
- Resource defense, patchy and defended by M [nesting habitat with limited resources =
better nest sites = resources = mates]
o Trade-off: resources and parental care [F access to food but less help rearing]
o EG: RW Blackbird [North America]; sexually dimorphic [F brown], M have
<10 F
- Female Defense;
o EG: Montezuma oropendola; M fight to control clusters of breeding F // F
build nests in isolated clumps// M = dominance hierarchies [alpha = >90%]
Limiting factor = nest sites.
- Leks;
o Small display sights without useful nest sites/ food.
o Communal [black grouse/ruff] or solitary [bower birds/pheasants]
o M bright, F duller// noisy displays// M dominate mating.
a. Hot Spot model; M gather in high density of F
b. Hot shot model; M gather round dominant experienced M
c. Female preference model; F to compare M directly
3. Cooperative Courtship;
a. Direct benefit; gain some mating anyway
b. Indirect benefit; helps relatives [inclusive fitness]
c. Delayed direct benefit; inherit patch
4. Polyandry;
- F with multiple mates [Spine and Jacana/ Dunnock]
Courtship and Display;
1. Ritualized Displays;
