Posted: November 11, 2004, 12:00 a.m. PDT
Some female birds select their mates by copying choices of other females rather than using their own judgment. According to biologist Luc-Alain Giraldson of the University of Quebec and colleagues, female bird mate-choice decisions can be non-independent and highly influenced by exposure to other females of the same species using mate-selection criteria that are borrowed. Such a lack of self-confidence in choosing a mate was not previously suspected.
Mate-choice copying has been documented in several avian species already, primarily those that lek. More research is underway. Some female birds select mates entirely on the basis of mate-choice criteria used by other females. Most often, those choices are determined by information revealing genetic quality or attractiveness in males. Such information can, in some cases, cause observer-females to alter their original mate-selection decisions.
When trying to select from among males of similar genetic quality and attractiveness, some female birds regularly engage in mate-copying, apparently to avoid making a wrong selection based on their own criteria. Furthermore, borrowed criteria used in mate selection seem to persist in the avian female memory and are repeatedly used, often in subsequent breeding seasons.
So far, it is not clear why some female birds copy mate selection in other females. It is possible that they somehow judge their own assessment criteria to be flawed.
Ongoing mate-choice copying research stems largely on observation of major biases in male mating success in some lekking species, where females tend to select males on the basis of criteria borrowed from other nearby females.
Preliminary evidence suggests that the frequency of copycat mating in females might be age-related. It might occur most often in younger inexperienced females seeking to establish mental guidelines for choosing the best mate from among a number of alternatives.