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Antipredatory behaviour, sexual selection and reproductive success in domestic sparrow (Passer domesticus).
Klvaňová, Alena ; Exnerová, Alice (advisor) ; Mlíkovský, Jiří (referee) ; Procházka, Petr (referee)
Anti-predator behaviour, sexual selection and reproductive success in the House Sparrow Passer domesticus Alena Klvaňová Summary of the thesis Individual components of parental care are disproportionally distributed among the parents in the House Sparrow. While the female broods the nestlings more often and feeds them more frequently, the male defends the nest more intensely. In an experimental study the parents did not adjust their nest defence intensity to behaviour of their partners, nor to brood parameters. Only males tended to defend the sooner broods more intensely, which is in concordance with the "brood value hypothesis". Male contribution to nestling feeding affected their body mass. Male nest defence intensity increased with the size of their melanin ornament. Thus, we assume that the ornament could signal male investment in this component of parental care, while it does not correlate with feeding frequency and time spent by incubation. This output is probably caused by pleiotropic effect of genes regulating melanogenesis, affecting e. g. testosterone plasma level, which is associated with increased agression and lower intensity of other components of parental care as nestling provisioning or incubation. We have also aked the question whether the anti-predator strategy in House Sparrow is stable...
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