Phys Org –
Why do animals help raise offspring that aren’t their own? A new study by an international team of researchers from Sweden, Canada and the UK shows that fish cooperate to raise another fish’s offspring to reduce their own risk of being eaten by a predator.
In an article published yesterday in the journal Nature Ecology and Evolution John Fitzpatrick, a lecturer at Stockholm University, and his colleagues show self interest is what leads to the evolution of complex cooperative societies in African cichlid fishes.
“In some group living animals – like meerkats – a few dominant individuals do all the breeding and receive help in raising their offspring from other members of the group. In birds and mammals, this helping behaviour evolves because the helpers are related to the offspring they are caring for. This wasn’t the case in cichlid fishes“, says Fitzpatrick, the senior author on the study.
To determine which behaviours are associated with cooperatively rearing offspring, the researchers examined the behaviours of almost 70 cichlid species living in Lake Tanganyika, Africa.