Facultative sex ratio adjustment in natural populations of wasps: cues of local mate competition and the precision of adaptation.

Sex ratio theory offers excellent opportunities to examine the extent to which individuals adaptively adjust their behavior in response to local conditions. Hamilton's theory of local mate competition, which predicts female-biased sex ratios in structured populations, has been extended in numerous directions to predict individual behavior in response to factors such as relative fecundity, time of oviposition, and relatedness between cofoundresses and between mates. These extended models assume that foundresses use different sources of information, and they have generally been untested or have only been tested in the laboratory.