Advanced Search

Browse by Discipline

Scientific Societies

E-print Alerts

Add E-prints

E-print Network

  Advanced Search  

Clutch size evolution under sexual con ict enhances the stability of mating systems

Summary: Clutch size evolution under sexual con ict enhances
the stability of mating systems
Henrik G. Smith1*
and Roger Ha« rdling2
Department of Animal Ecology, and 2
Department of Theoretical Ecology, Ecology Building, Lund University, S-223 62 Lund, Sweden
Models of optimal clutch size often implicitly assume a situation with uniparental care. However, the
evolutionary con£ict between males and females over the division of parental care will have a major
in£uence on the evolution of clutch size. Since clutch size is a female trait, a male has little possibility of
directly in£uencing it. However, the optimal clutch size from a female's perspective will depend on the
amount of paternal care her mate is expected to provide. The sexual con£ict over parental care will in its
turn be a”ected by clutch size, since a larger clutch makes male care more valuable. Hence, there will be
joint evolution of mating system and clutch size. In this paper, we demonstrate that this joint evolution
will tend to stabilize the mating system. In a situation with conventional sex roles, this joint evolution
might result in either increased clutch size and biparental care or reduced clutch size and uniparental
female care. Under some circumstances the initial conditions might determine which will be the outcome.
These results demonstrate that it may be di¤cult to deduce whether biparental care evolved because of
few opportunities for breeding males increasing their ¢tness by attracting additional mates or because of
the importance of male care for o”spring ¢tness by studying prevailing mating systems using, for


Source: Agrell, Jep - Department of Ecology, Lunds Universitet


Collections: Environmental Sciences and Ecology