The Biology Coach: AH Biology, Topic 2, Key Area 4b

Monogamy

The mating of a pair of animals to the exclusion of all others

Polygamy

Individuals of one sex has more than one mate

Polygyny

One male mates exclusively with a group of females

Polyandry

One female mates with a number of males in the same breeding season

Species-specific sign stimuli

A species-specific sign that an organism produces during courtship rituals that results in a fixed action response

Sexual dimorphism is a product of...

sexual selection because it offers no advantage to survival in the environment - instead, in increases the chances of finding a mate

Reverse sexual dimorphism

where the female is more conspicuous, e.g. in the Angler fish

Female choice

involves females assessing honest signals of the fitness of males.

Honest signals

Can indicate favourable alleles that increase the chances of survival of offspring (fitness) or a low parasite burden suggesting a healthy individual.

Lek

An area where the males of a lekking species, e.g. grouse, will gather to display to the females.

Dominant males at a lek

Dominant males occupy the centre of the lek

Satellite males at a lek

Subordinate or juvenile males found at the fringes of the lek.

Male-male rivalry

often involves conflict (real or ritualised), whereby successful males will be more successful in "female choice". This might reflect weaponry, e.g. antlers, tusks, horns