African fish choose safety over sex 
CA Source: CBC News 1/18/2010

Safety in numbers wins out over an increased chance of sex when it comes to a native African fish, a new study finds.

The results, recently published in the journal Biology Letters, suggest a species of cichlid fish employs a complex decision-making process when joining a social group.

Lead author University of New South Wales biologist Alex Jordan says the strategy employed by the fish is likely to be replicated in other group-joining species.

For the research, Jordan examined the choices made by Neolamprologus pulcher found in Lake Tanganyika in Tanzania.
 

He says N. pulcher is unusual because it lives in social groups that include both breeders and helpers.

Jordan says the breeding pair can have between two to seven helpers who do tasks such as cleaning the nest, defending territory and looking after the eggs.

The helpers do not breed, instead waiting until a breeding position becomes available through the death of a more senior member of the group.

Previous genetic work has shown that N. pulcher within a group are unrelated, suggesting the young disperse to other groups.

 
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