Effect of reproductive site limitation on the intensity of sexual selection and the quality of paternal care: a meta-analysis

• Autor(a) principal: Alissa, Louise M.
• Data de Publicação: 2018
• Tipo de documento: Dissertação
• Idioma: eng
• Título da fonte: Biblioteca Digital de Teses e Dissertações da USP
• Texto Completo: http://www.teses.usp.br/teses/disponiveis/41/41134/tde-23102018-090541/
• topic: Alternative reproductive tactics; Competição entre machos; Competição espermática; Defesa de recursos; Environmental potential for polygyny; Limitação de recursos; Male-male competition; Mating system; Parental effort; Paternidade; Paternity; Potencial ambiental para a poliginia; Resource defense; Resource limitation; Sistema de acasalamento; Sperm competition; Táticas alternativas de reprodução

The availability of reproductive sites is a major factor shaping the behavior of males and females in species with resource-based mating systems. Using a meta-analytic approach, we tested five predictions directly or indirectly derived from the mating system theory. We expected that reproductive site limitation would lead to: (1) intense male-male competition for resource possession; (2) high variance in male reproductive success, generating high values of opportunity for sexual selection; (3) high intensity of selection on male traits related to resource possession; (4) high sperm competition risk; and (5) low quality of paternal care. We compiled information from observational and experimental studies that compared the reproductive behavior of individuals of the same species under low and high reproductive site limitation. We found that, when reproductive sites are limited, there is a slight increase in male-male competition, with higher rates of nest takeover and agonistic interactions, and a slight increase in the selection gradient on male traits, with successful males tending to be larger than unsuccessful males. Reproductive site limitation has no consistent effect on the opportunity for sexual selection and on the sperm competition risk. However, territorial males invest more in gonads and lose less paternity when reproductive sites are limited. There is also no clear effect of reproductive site limitation on the quality of paternal care, but few studies have addressed this subject. Taken together, our findings indicate that predictions on how reproductive site limitation affects several aspects of resource-based mating systems have weak empirical support. These predictions do not consider the plasticity in the mating tactics of males and females, which make them too simplistic. Moreover, since the original proposition of the mating system theory, our understanding of sperm competition increased a lot. We now know that accurate predictions on the intensity and direction of sexual selection should take into account both pre- and post-copulatory processes. Finally, the interplay between sexual selection and parental care is complex, and the original framework of mating system theory does not provide sufficient elements to derive clear and taxonomically broad predictions