Editor's Summary
8 September 2005
A fighting chance
It's not the taking part that counts, it's the winning. That's the conclusion to be drawn from a study of the combative Mozambique tilapia fish. These fish — the males that is — will show aggressive intent towards a rival and also towards their own image in a mirror. But the act of fighting does not induce a hormonal response (increased circulating androgen) when there is no outcome to the contest in a 'virtual' fight; that happens only in genuine combat. This may be an adaptive mechanism allowing individuals to mount an androgen response and enhance their social status once they have assessed the fighting ability of their challenger.
Brief Communications: Behavioural endocrinology: No hormonal response in tied fights
Fish androgens may start to surge only when there seems to be a good chance of winning a contest.
Rui F. Oliveira, Luis A. Carneiro and Adelino V. M. Canário
doi: 10.1038/437207a