3.6 Social Insects and Social Behaviour

Question 1

What is social hierarchy?

Answer 1

social hierarchy is when animals within a social group claim a ranked position within that group, determined by both aggressive and display behaviours
positions range from the strongest to the weakest individual within the group
social hierarchy can be seen in packs of wolves and social groups of chimpanzees

Question 2

What are advantages of social hierarchy?

Answer 2

reduces physical fighting and injury
conserves energy
genes from the strongest individuals are passed onto the next generation

Question 3

DONT FORGET!

Answer 3

Social organisms live in groups and may work together to their mutual benefit
they have behaviours that are adapted to group living

Question 4

What is cooperative hunting?

Answer 4

animals hunt together in a group in order to maximise the chance of finding and bringing down prey.
in this way larger prey animals may be hunted, providing more food energy
example; harris hawks hunt rabbits in teams

Question 5

What are the advantages of cooperative hunting?

Answer 5

kill is shared among all members of a hunting group
larger prey may be hunted
higher chance of finding and killing prey than if hunting individually

Question 6

What are social defence against predation?

Answer 6

vigilance
herd movement
altruism
kin selection

Question 7

What is vigilance?

Answer 7

individual members of a social group will look out for predators while others feed
this benefits the whole group and increases the chances of survival
vigilance behaviour can be seen in prairie dogs and barnacle geese while grazing

Question 8

What is herd movement?

Answer 8

a herd of animals will keep close together while travelling as there is safety in numbers
females and young are positioned towards the centre of the herd for protection
with watchful males on the perimeter

group works together to mob or attack a predator to protect offspring
flocking schooling and herding - animals move together to make it more difficult for predators to pick off individuals from a group

Question 9

What is altruism?

Answer 9

this is unselfish behaviour which benefits the survival chances of other members of a social group, at a cost to the individual.

Question 10

what is reciprocal altruism?

Answer 10

In social species such as chimpanzees, the cost of helping another individual is outweighed if the helper is repaid this is reciprocal altruism

Question 11

Example of altruism - Vampire bats?

Answer 11

vampire bats who have hunted successfully might share food at the roots with those who have not the successful hunter on one occasion might be unsuccessful later and need to obtain food from a previous recipient

Question 12

What is kin selection?

Answer 12

this is altruistic behaviour which specifically benefits the survival chances of close relatives within a social group
e.g. adult chimpanzees giving their food to juvenile members of the social group
this ensures survival of shared genes by increasing the juveniles chances of reproductive success.

Question 13

Example of Kin selection - Donor long tailed tits?

Answer 13

donor long tailed tits with no offspring might feed the recipient offspring might feed the recipient offspring of other parents in times of food shortage long tailed tits live in loose colonies with related individuals so that recipient offspring of one parent might share some of the donors genes

Question 14

DONT FORGET

Answer 14

social behaviours have evolved and are adaptations which increase an organisms reproductive success

Question 15

What will a truly social insect society will have?

Answer 15

cooperative care of the young insects
parents and their offspring living together
the development of a caste system

Question 16

What are social insect societies?

Answer 16

ants, bees, termites and wasps live in colonies where different adults play different roles
reproduction and survival depend on all members of the colony working together
the majority are workers who labour together to raise their relatives
the efficiency and success of the group depends on the workers foregoing reproduction, which allows them to focus all their efforts on their other tasks including defence of the colony
this ensures that their genes are passed onto the next and following generations through their breeding relatives

Question 17

What is communication in social insects?

Answer 17

the social structures of insect colonies relies on effective communication:

1. honey bee workers perform a waggle dance to inform the other workers of the direction and distance to a particular food source
2. some insects use chemical messengers known as pheromones. Certain ants, after finding food, lay down a pheromone trail when returning to the nest. This attracts and guides other ants to the food source

Question 18

Within a bee colony there exists three distinct social levels. Name and explain them?

Answer 18

queen bee - is the only bee within the colony that produces eggs. other female bees do not produce eggs and become worker bees. The eggs of the queen bee are fertilised by male drone bees

worker bee - female daughters of the queen bee and share similar genes. instead of reproducing they defend and maintain the hive together with the drone bees

drone bee - male bees that fertilise the eggs laid by the queen bee. they work in the hive to maximise the survival chances of the offspring by guarding the hive, foraging for food, cleaning and building new cells, storing pollen and feeding larvae

Question 19

What are keystone species?

Answer 19

keystone species are those which have a particularly important impact on their ecosystem
without keystone species, the species diversity of the ecosystem would decrease and the ecosystem may cease to exist
social insects are often keystone species
bees, ants, and termites exist within complex social structures benefiting the environment by providing ecosystem services such as pollination, decomposition and natural biological control of populations

Question 20

What are examples of keystone species?

Answer 20

honey, bees and wasps - pollinate flowering plants, including many food crops
termites - build mounds which provide habitats for other species; provide protein rich food for many animals; are decomposers, so recycle soil nutrients
ants - pollination, nutrient turnover, seed dispersal

Question 21

DONT FORGET

Answer 21

pollination is the transfer of pollen from anther to stigma in a flowering plant
without pollination plants could not reproduce

Question 22

What are primates?

Answer 22

primates are humans, a large, diverse group of mammals including monkeys and apes

Question 23

What does the long period of parental care in primates allow?

Answer 23

gives time for young to learn complex social behaviours by watching and copying others
chimpanzees learn to make tools such as termite fishing sticks and leaf sponges

Question 24

what are social groups in primates?

Answer 24

most primates live in social groups where there is competition for resources (such as food/mate) so conflict can arise.

Question 25

Benefit from living in a group?

Answer 25

provide protection from predators

Question 26

What do primate species exhibit?

Answer 26

exhibits a range of complex behaviours which help to support the social structure of the group and reduce unnecessary conflict

Question 27

what does the social structure of each species depends on?

Answer 27

its particular ecological niche - the role it plays in its ecosystem
the distribution of its resources - the type of food eaten and its availability
the taxonomic group to which it belongs - different species display different behaviours

Question 28

What are 4 behaviours in primates?

Answer 28

parental care
ritualistic displays
appeasement/ submissive behaviour
alliances with others/ friendships

Question 29

What are the features of these behaviours?

Answer 29

extends to several years
reinforces a leader’s position within a group, for example use of vocal sounds and chest beating
use of facial expressions, lower body posture to signal ‘standing down’
social bonds develop between individuals

Question 30

What are the advantages of these behaviours?

Answer 30

young animals learn complex social behaviours from parents
challenger is able to assess threat
reduces physical fighting and potentially fatal injury
improves position within social hierarchy

Question 31

the success of social groups in primates allows them to do what?

Answer 31

allows them to exploit a wide variety of ecological niches within a particular ecosystem, such as a forest

Question 32

where do chimpanzees live?

Answer 32

live in trees an on the forest floor, eating fruit, seeds and insects

Question 33

where do bushbabys live?

Answer 33

they live solely in the trees, feed mainly on insects and pollinate flowers that open at night

Question 34

What is resource distribution?

Answer 34

primates are able to feed on both plants and animals within their own geographical range in a large forest ecosystem
although mainly herbivorous, chimpanzees will occasionally hunt monkeys cooperatively in a group and share the kill between them
chimpanzees have also learned from their parents how to use a thin stick to collect termites from inside the trunk of a tree

Question 35

What is a taxonomic group?

Answer 35

chimpanzees, baboons and monkeys are all primates but belong to different classified groups
these are called taxonomic groups
members of each taxonomic group are similar in terms of resource requirements, habitat and type of social structure, but are able to inhabit different ecological niches

Question 36

TOPTIP

Answer 36

agonistic behaviours are seen through situations of conflict and include fighting and running away