Date: March 29, 2016
Source: University of Bern
Variation in social organization and
behavior of highly social animals like cichlids is primarily explained by
predation risk and related ecological factors. This stresses the significance
of predation for social evolution.
Sociality is a ubiquitous feature of
life, but the reasons why animals cluster together can vary. In nature, there
is great diversity in social organization and in the complexity of interactions
among group members. It is widely accepted that high predation risk may select
for group living, but predation is not regarded as an important driver of
social complexity.
This view neglects the important effect
of predation on dispersal and offspring survival, which may require cooperation
among group members. The significance of predation for the evolution of social
complexity can be well illustrated by behavioural and morphological adaptations
of highly social animals showing division of labour, such as ants and
cooperatively breeding fishes like cichlids.
Long-time study of eight fish populations
In several species of cichlids in Lake Tanganyika , for example, groups consist of many
individuals differing in size, age, dominance rank and relatedness. Group
members typically cooperate in brood care, territory maintenance and defence,
and they decide about their cooperative effort in dependence of relatedness to
beneficiaries and the outcome of negotiations with other group members.
Importantly, the form and function of social organization varies considerably
among different populations of the same species, which enables to study the
significance of ecological factors for social organization.
No comments:
Post a Comment
You only need to enter your comment once! Comments will appear once they have been moderated. This is so as to stop the would-be comedian who has been spamming the comments here with inane and often offensive remarks. You know who you are!