social behaviour 6

• Main behaviors adopted by animals when living in social groups

  • Social hierarchy
  • Co-operative hunting
  • Social defence
• Social hierarchy


  A rank order within a group of animals consisting of dominant and subordinate members
• Dominant individuals

  Carry out ritualistic (threat) displays
• Subordinate animals

  Carry out appeasement behavior to reduce conflict
• Social hierarchies

  Increase the chances of dominant animal's favorable genes being passed onto offspring
• Animals can often form alliances in social hierarchies

  To increase their social status within the group
• Social hierarchy

  • The pecking order in chickens
  • The social groups of wolves
• Co-operative hunting

  May benefit subordinate animals as well as dominant ones, as they gain more food than by foraging alone
• Co-operative hunting

  Less energy is used per individual and enables larger prey to be caught and increases the chance of success
• Co-operative hunting

  • Lions preying on large buffalo
  • Killer whales (Orca) hunting blue whales
• Social defence strategies

  Increase the chances of survival as some individuals can watch for predators whilst others can forage for food
• Groups adopt specialised formations when under attack

  Protecting their young
• Social defence

  • Meerkats standing guard to allow others to forage for food
  • Large adult Walruses forming a circle surrounding young in the middle when under attack from polar bears
• Altruistic behavior

  Harms the donor individual but benefits the recipient
• Reciprocal altruism

  When the roles of donor and recipient later reverse, often occur in social animals
• The donor will benefit in kin selection

  In terms of the increased chances of survival of shared genes in the recipient's offspring or future offspring
• Examples of social insects

  • Bees
  • Wasps
  • Ants
  • Termites
• In beehives, there are only a few individuals that contribute to the society reproductively (Queens and drones). Most members of the colony are sterile workers who co-operate with relatives to raise relatives. This increases the chances of the survival of shared genes.
• Other roles of workers

  • Collect pollen
  • Defending the hive
  • Carrying out waggle dances to show the direction of food
• Primates have a long period of parental care

  To allow learning of complex social behaviors
• Complex social behaviors

  Reduce conflict through ritualistic displays and appeasement behavior
• Complex social behaviors in primates

  • Grooming
  • Facial expressions
  • Body posture
  • Sexual presentation
• Alliances will also form between individuals

  Which are often used to increase social status within the group