Intra-specific co-operative behaviour
description
Transcript of Intra-specific co-operative behaviour
Intra-specific co-operative behaviour
Group formationCourtship 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
• R-Strategy – Shell fish, bacteria,insects
• K – strategy – Kakapo, whales, humans
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