Social Behaviour

Question 1

What are the advantages of living in a social group?

Answer 1

Protection

Easier to catch food

Easier to find a mate

Have help with raising young

Question 2

What is a social hierarchy?

Answer 2

A system where members of social groups are organised into a rank order resulting from aggressive behaviour between different members of groups

A high ranking individual dominates the subordinates

Question 3

Advantages of a social hierarchy

Answer 3

Increase species chance of survival because:

• agression between members is ritualised so real fighting is kept to a minimum avoiding serious injury
• energy is conserved
• experienced leadership is guaranteed
• most powerful and fittest will pass on genes to next generation

Question 4

What is co-operative hunting?

Answer 4

Predatory mammals often hunt together as groups to increase their hunting success

Question 5

Advantages of cooperative hunting

Answer 5

All members of a group get a share and benefit (although dominant animals get more)

They can tackle larger prey so gain more food than hunting alone

Minimises injury

Question 6

Social mechanisms of défense

Answer 6

Safety in numbers - staying in a large group protects many animals from predators as there are many eyes to look out for predators and alert the group and it is harder for predators to pick out one animal

Defensive formation - females and young in the centre

Strict social hierarchy - always march in a certain order

Question 7

What is altruistic behaviour?

Answer 7

Unselfish behaviour which is detrimental to the donor and beneficial to the recipient

Question 8

Two types of altruistic behaviour

Answer 8

Reciprocal Altruism

Kin Selection

Question 9

What is reciprocal altruism?

Answer 9

One animal giving help to another animal in the prospect of the favour being returned

Question 10

What is Kin selection?

Answer 10

Where individuals reduce their own net lifetime production of offspring in order to help their relatives reproduce

May involve personal sacrifice but it is not a sacrifice in evolutionary terms

It is a sacrifice where the benefits outweigh the costs

Question 11

Why do social insects express extreme altruism

Answer 11

Kin selection

Workers are sterile yet they help their siblings survive and reproduce so the shared genes are still passed on

Question 12

Features of social insects

Answer 12

A division of labour exists:

Food gathering/defence = sterile members

Reproduction = few fertile individuals

Question 13

Three types of honeybees

Answer 13

Queen: female that produces eggs

Drones: haploid males whose role is purely reproductive, to find and mate with the Queen

Workers: nonreproducing females (all sisters) that maintain and defend the hive rather than reproduce

(Drones and workers are the Queen’s offspring)

Question 14

Describe signalling in honeybees

Answer 14

Workers perform a waggle dance to communicate:

• The distance of food
• The direction of food
• The richness of the supply

They do this to minimise energy expenditure by other members of the hive

Question 15

Describe social behaviour in ants

Answer 15

Ants search for food in a snaking pattern

They leave scent markers for other ants to follow the trail

Question 16

What is a keystone species?

Answer 16

Play a critical role in the structure and working of an ecosystem

Their absence could lead to instability and collapse of an ecosystem

Question 17

What are ecosystem services?

Answer 17

The benefits to humans provided by natural ecosystems

E.g. pollination

Question 18

Describe parental care in Primate behaviour

Answer 18

Small number of offspring but take great care of them:
Feeding, cleaning, protection

Young primates have time to learn complex social behaviours including communication

Question 19

Describe ritualistic threat displays

Answer 19

Exhibit a threat display that makes them look larger and fiercer

One will make itself more intimidating and the other will then concede defeat and adopt appeasement behaviour

Question 20

Describe appeasement behaviour

Answer 20

Body made to look smaller, flatter, motionless and unthreatening

Females and subordinate males use appeasement behaviours to show acceptance of dominant male

Reduces needless hostility

Question 21

Examples of appeasement behaviour and benefits of it

Answer 21

Grooming, facial expression, body position, sexual presentation

Reduces tension, prevents conflict, establishes dominance, avoid aggression

Question 22

How can social status within a social hierarchy change?

Answer 22

Not always static and may change such as through alliances

Question 23

What is the social structure of private societies related to?

Answer 23

Ecological niche

Resource distribution

Taxonomic group

Question 24

What is group size and organisation of social structures affected by?

Answer 24

Predator pressures

Availability and distribution of resources