SOCIAL BEHAVIOUR IN ANIMALS
Social behaviour can simply be defined as an interaction between two or more organisms of the same species. The scientific study of social behaviour is called ‘sociology’. It is the scientific study of how the members of a community are influenced by the actual, imagined or implied presence of other members of the community or the other communities of organisms.
A lot of animals, including humans, share similar patterns of social behaviours such as aggression and bonding. In determining the social behaviour of a particular group and population of animals, genetics and culture must be considered.
While one may be very social, others play different functional roles social behaviour called division of labour.
Natural selection favours social behaviour within a group because individual animals that interact with others in the group tend to survive and reproduce better. Aggregation is the collection or group of animals in a common location Not all aggregation of animals are social (non-social grouping).
Social behaviour evolved along two pathways; familial and parasocial pathways.
- Familial Pathway: is the type of social behaviour that is found in a closely related group of animals.
- Parasocial Pathway: consists of solitary specie, later unrelated adults of the same generation forming groups centring around resources.
ADVANTAGES OF SOCIAL BEHAVIOUR
- pack or group hunting in hyenas, lions,
- better ability to defend resources,
- easier to find or secure mates
DISADVANTAGES OF SOCIAL BEHAVIOUR
- Resource competition bulls (buffalo) fight among each other for dominance,
- Risk of parasite transmission,
TYPES OF SOCIAL BEHAVIOUR
There are two main types, Collective animal behaviour and Aggressive behaviour.
Collective Animal Behaviour :
This involves the coordination of animals of same/related species in large groups. Eg, flocking birds, an aggregate of worms, etc.
Function Of Collective Animal Behaviour (AGGREGATION)
Animals aggregate for a specific function in the environment which could be categorized into four based on the function of an animal in the community;
- social and genetic interaction,
- anti-predator association,
- enhanced foraging, and
- increased locomotion efficiency.
Social and Genetic Interaction: This interaction deals with the calming effect and reduced stress exhibited by animals when they interact with members of the same species.
Anti-predator Function: Aggregation in animals serves as a protective measure in most animal species, in the sense that the large aggregate gives a defensive group effect that may frighten and unwitty predators.
Enhanced Foraging: Animals tend to find fodder easily when they are in groups because the cooperative search would reduce time spent in identifying portions of the habitat with rich food than it would an individual person.
Threat: These are species-specific behaviours such as vocalization, odour, facial or body movement that signal the intent to display aggression.
Submission: These are species-specific behaviour such as vocalization, posture and odours that signal non-aggressiveness and reduce further attacks from aggressive individuals.
Aggressive Behaviours: It stems from aggression which is an overt, often harmful social interaction with the intent of inflicting damage or other unpleasantness on another individual. It is classified into two; Direct and indirect aggression.
Functions of Aggression :
- Establishment of rank in the social hierarchy,
- Defence of mate/offspring,
- Displacement of other animals from a source of food.
Aggression in animals can be distinguished based on motivation and they include :
- Agression in response to provocation
- Aggression directed towards an objective.
Forms of Aggression include :
- Anti-predatory aggression,
- dominance of aggression,
- species-specific aggression,
- inter-male aggression,
- maternal aggression,
- Sex-related aggression,
- territorial aggression,
- isolation-induced aggression,
- brain-stimulus induced aggression (hypothalamus).
- Inter-specific Aggression: This is observed between animals in a different group.
- Intra-specific Aggression: This is observed between animals in the same group.
Conflict Resolution In Animals
Conflicts caused by aggression can occur between parties in the animal society, common and most obvious include;
- between potential mating partners,
- between parent and offspring,
- between siblings,
- between competitors for available resources.
Forms of Resolving Conflict
- trial of strength
Four Main Perspectives To Explain Aggression
Necessary predisposing factors which enhance the evolution of aggression include ;
- violence and conflict
(a) The brain pathway: controls panel of the nervous system, plays a major role in the innate adaptive behaviours of the animal.
Aggression in humans is associated with abnormalities in three principal regulatory systems of the body
i) The serotonin system
ii) Catecholamine system
iii) hypothalamus-pituitary-adrenal axis
b) Testosterone: Males are more aggressive than females because of a higher level of testosterone than in females.
3) Genetic Explanation Of Aggression
The aggressive tendency is a continuous phenotypic character that is controlled by numerous genes in the animals. Aggression in animals come out of the intricate interaction between the assortment of genes and the environment of the animal.
Management Of Aggression
Tranquilizers (azaperone) are administered as a short term control measure against aggression in husbandry systems, also mixing individuals during a period of lower activity.
Behaviour Patterns In Animals
A behaviour pattern may be defined as a segment of behaviour having a definite adaptive function and is a basic functional unit of behaviour. Social organization, however, is defined by six major functional patterns of behaviour
a) Cooperation: is ‘doing the same thing’ as others
b) Dominance status: social hierarchies and pecking order in a dominance hierarchy in which animals within a group are arranged according to status.
Advantages of Pecking Order:
- it establishes order,
- it ensures that resources are shared out so that not only the fittest can survive.
c) Territorial behaviour: is common to vertebrates except for amphibians, but is rare in non-vertebrates.
d) Leadership: The emergent leader sets the direction and pace of the group.
e) Parental care and mutual stimulation: is associated with complex and long-lasting bond
f) Mutual simulation: is common in most species.