Causes of Behaviour : Proximate And Ultimate




Causes of Behaviour : Proximate And Ultimate

1. Discuss proximate and unltimate causes of animal behaviour.

Scientists have identified two main types of causes of behaviour: Proximate causes and Ultimate causes.

1. Proximate Causes of Animal Behaviour

Example: A female animal choose to mate with a particular male. The possible proximate explanation can be that the particular male produced more intense signals, leading to elevated hormone levels in the female inducing copulatory behaviour.

It means proximate causes of behaviour include those internal mechanisms that enable an organism to execute the specific required behaviour. This explain how an animal or individual manages to carry out a specific behavioural activity. It means proximate causes influence the mechanisms within an animal, enabling it to behave in certin ways.

These mechanisms include:

1. Genetic: Developmental mechanisms such as:

  • Effects of heredity on behaviour.

  • Genetic environmental interactions during development that produce sensory motor mechanisms.

2. Sensory: Motor mechanisms, such as:

  • Operation of nervous system to detect environmental stimuli.

  • Operation of hormonal system for the adjustment of internal responsiveness.

  • Operation of skeletal muscular ststems for carrying out responses.

Causative factors of first category are associated with the influence of heredity on the development special receptors, brain cells and muscle controllers. This helps in understanding the process of channelising the proliferation and specialisation of cells along certain pathways. In addition, to the development of differential pathways, it is necessary to understand the mechanisms of detection of stimulation and relaying of messages to activate the muscular respinse. This is called neurophysiological basis of behaviour.

The neurophysiological basis of behaviour includes neural, hormonal and chemical mechanisms within the body to include specific behaviour.

In case moth expose its hindwings when pecked because its nervous ststem controls the wing flipping response. This is proximate explanation of behavour.

2. Ultimate Causes of Behaviour

Ultimate causes of behaviour include the evolutionary causes of behaviour. These are associated with origin of a particular behaviour and modifications of the genes for that behaviour and also their inheritance generation after generation. These are also called distal causes and are considered to be the real reasons for the behaviour in action.

Example: Female animals after display preferences for male’s display traits, such as attractive colour patterns, songs or courtship behaviours.

The ultimate explanation for such preference of sexual selection is to have more attractive or more vigorous male offspring by the female.

Thus, ultimate causes are the reasons behind the mechanism of behavioural activity.

The history of differential reproductive sucess among individuals determines what genes survive from generation to generation and therefore, what genetic information is available to influence the development of a specific behaviour in current generation. Therefore, ultimate causes of behaviour separated into:

1. Origin of the behaviour and its alteration over time, i.e., the historical pathway leading to behaviour.

2. Past effects of natural selection in shaping the current behaviour, i.e., the past and current utility of behaviour in terms of reproductive success or the evolutionary importance.

Thus, ultimate explanations focus on causes that occur in populations over many generations and arise because natural selection has shaped the proximate mechanisms and behavioural abilities of individuals in the past.

Very Short Answer Type Questions

1. What is proximate hypothesis?

Ans: A proximate hypothesis relates to the mechanisms or methods by which an animal performs a specific behaviour.

2. What do you mean by ultimate hypothesis about animal behaviour?

Ans: An ultimate behaviour relates to the evolutionary reason for the behaviour.

Credit:- Dr. Veer Bala Rastogi (KedarNathRamNath)