3.6 Social Behaviour

Question 1

How do many animals live?

Answer 1

In social groups and have behaviours that are adapted to group living such as social hierarchy, co-operative hunting, and social defence

Question 2

How are animals ranked in their groups?

Answer 2

By dominant and subordinate behaviours

Question 3

What are the advantages of having dominant and subordinate members in a group?

Answer 3

• Aggression between it’s members becomes ritualised
• Real fighting is kept to a minimum
• Serious injury is normally avoided
• Energy is conserved
• Experience leadership is guaranteed
• The most powerful animals are most likely to pass their genes on to the next generation

Question 4

Advantages of social hierarchy

Answer 4

• Reduces conflict
• Increases chance of dominant animal favourable genes being passed on to offspring
• Animals often form alliances in social hierarchies to increase their social status within the group

Question 5

Co-operative hunting advantages

Answer 5

• Benefits subordinate animals as well as dominant ones
• Less energy used
• Enables large pray to be caught and increase chance of success

Question 6

Social mechanisms of defence advantages

Answer 6

• Increases the chance of survival as some individuals can watch for predators whilst others can forage for food

Question 7

Altruism

Answer 7

A behaviour that harms the donor but benefits the recipient

Question 8

Reciprocal altruism

Answer 8

The roles of donor and recipient later reverse

Question 9

Kin selection

Answer 9

A behaviour that appears to be altruistic can be common between a donor and a recipient if they are related to - the donor will benefit in kin selection in terms of the increased chances of survival of shared genes in the recipients offspring or future offspring

Question 10

Social insects

Answer 10

Social insects and the structure of their society in which only some individuals (queens and drones) contribute reproductively. Most members of the colony are sterile workers who co-operate with close relatives to raise relatives

Question 11

Primates

Answer 11

A group of placental animals possessing dexterous hands and feet, opposable first digits, stereoscopic vision, highly developed brain. They have a long period of parental care to allow learning of complex social behaviour

Question 12

Complex social behaviour

Answer 12

Supports the social hierarchy

Question 13

Examples of social behaviour

Answer 13

Grooming - Reduces tension, builds alliances, can help reconciliation after a fight
Facial expressions - Closed eyes: given up, Grinning: appease dominant individuals it fears
Body posture - Prostrate or low posture shows respect to dominate male
Sexual presentation - Appease a dominant male, this arouses a response that is an alternative to aggression