Living fast and dangerously: Hormones influence the 'pace of life' of songbirds
Thursday, June 17, 2010 - 11:40
in Biology & Nature
Human beings, fish, reptiles and birds have the same hormones in their blood with very similar functions. But why does one find hormone values in some species that are ten times higher than in others? Scientists have now discovered that the differing concentrations in birds of the stress hormone, corticosterone, and the reproductive hormone, testosterone, are correlated with the "pace of life". They control whether energy is invested into reproduction, i.e. the number of eggs laid and the breeding attempts in a given season, or more into longevity, i.e. immune function or the flight response in times of danger.