Ineffective nuptial gifts suggest female emancipation from sensory exploitation

摘要: Male sensory exploitation of female gustatory pre-existing bias has been proposed for the origin nuptial gifts in insects and spiders. This sexual trait may have beneficial to both sexes, giving mating survival advantages males providing nutritional resources females. However, evolution deceptive worthless is against females’ interests trigger a co-evolutionary change preferences. We evaluated preferences adaptive function gift spider Trechaleoides keyserlingi. The genus belongs understudied Neotropical family Trechaleidae which are widespread. composed only two species, seems be absent sister creating relevant scenario understanding processes. In laboratory, we found that although invested more when encountering mated females compared unmated, they had similar access duration than lacking gift. also an absence choice between offering nutritive gifts. Few were aggressive cannibalized males, did not find evidence protected from cannibalism. field, 50% items. congruent with laboratory findings where seem better attract females, discuss context bias. therefore propose evolved indifference gift-giving this species represents currently non-functional remnant behaviour. Nutritive can exploit preferences, mutual benefits sexes: increase success survival, while their fecundity. But offer leading suboptimal matings, turn evolve trait. ideal examine process because behaviour present one other. examined its T. invest but gain no reproductive advantage, as equally likely mate them regardless whether offered or was worthless. changed