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Intra-specific co-operative behaviour. Group formation Courtship and pair-bond formation Parental care. Group Formation. When members of a group come together to undertake tasks e.g Hunting. Advantages to forming groups. Team work leads to increased success rate.
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Intra-specific co-operative behaviour Group formation Courtship and pair-bond formation Parental care
Group Formation • When members of a group come together to undertake tasks e.g Hunting
Advantages to forming groups • Team work leads to increased success rate. • Less predation as can have members of the group on “look out” • Older members protect young or weak individuals • Large numbers can cause confusion for predators • Breeding sites are located within a boundary that is protected by members of a group
Disadvantages • Competition is increased • Disease can spread faster • Parasites (e.g. fleas) spread faster • Increases conflict between members
Courtship/Pair bonding • Requires co-operation, suppression of aggressive behaviours and communication. • Usually females make the choice who they mate with, but both partners need to make sure; • They are the same species • Both fertile • Both fully prepared to mate.
Courtship • Males usually will compete for the attention of females by • Competing with other males by fighting or ritualised combat • Compete indirectly by attracting females by displays and adornments • E.g. antlers in deer, brightly coloured feathers in peacocks, singing and dancing of many bird species, producing pheromones.
Pair-bond Relationship • A stable relationship between animals of the opposite sex that ensures co-operative behaviour on mating and rearing of the young
Parental Care • Survival depends on successfully breeding adequate numbers of offspring. • Can be achieved by to possible strategies • R-strategy – produce large numbers of unprepared offspring with a low chance of survival • K-strategy – produce few, well prepared offspring which have a high chance of survival
Parental Care • Degree of parental care depends on the species • E.g. eggs buried and then abandoned (many fish species), nest constructed and defended, offspring themselves defended • Often those species that have a high degree of parental care will teach their offspring how to find food, where to find water, how to make a home etc.
Reproductive Strategies • Monogamy – each mating with only one member of the opposite sex (often for life) • Polygyny – males mate with many females thus fathering many offspring • Polygamy – dominant males mates with a harem of females • Polyandry – females mate with more than one male • Polygynadry (promiscuity) – both male and female mate with more than one member of the opposite sex