Search results for "MATING SYSTEMS"
showing 3 items of 3 documents
Men with elevated testosterone levels show more affiliative behaviors during contact with women
2012
Testosterone (T) is thought to play a key role in male–male competition and courtship in many vertebrates, but its precise effects are unclear. We explored whether courtship behaviour in humans is modulated and preceded by changes in T. Pairs of healthy male students first competed in a non-physical contest in which their T levels became elevated. Each participant then had a short, informal interaction with either an unfamiliar man or woman. The sex of the stimulus person did not affect the participants' behaviour overall. However, in interactions with women, those men who had experienced a greater T increase during the contest subsequently showed more interest in the woman, engaged in more…
Data from: The evolutionary dynamics of adaptive virginity, sex-allocation and altruistic helping in haplodiploid animals
2017
In haplodiploids, females can produce sons from unfertilized eggs without mating. However, virgin reproduction is usually considered to be a result of a failure to mate, rather than an adaptation. Here we build an analytical model for evolution of virgin reproduction, sex-allocation, and altruistic female helping in haplodiploid taxa. We show that when mating is costly (e.g. when mating increases predation risk), virginity can evolve as an adaptive female reproductive strategy. Furthermore, adaptive virginity results in strongly divergent sex-ratios in mated and virgin queen nests (‘split sex ratios’), which promotes the evolution of altruistic helping by daughters in mated queen nests. How…
Data from: Sexually selected traits evolve positive allometry when some matings occur irrespective of the trait
2013
Positive allometry of secondary sexual traits (whereby larger individuals have disproportionally larger traits than smaller individuals) has been called one of the most pervasive and poorly understood regularities in the study of animal form and function. Its widespread occurrence is in contrast with theoretical predictions that it should evolve only under rather special circumstances.