Behavioral Modification as a Means of Reducing the Cost of Reproduction

摘要: Because relative clutch mass (RCM) adversely affects locomotor performance, and therefore presumably the survival rate of pregnant females, it is assumed to be constrained by natural selection. I propose that changes in antipredator tactics during pregnancy can reduce females' dependence on locomotion, thereby alleviating selection acting RCM. Such a behavioral shift would more likely response against poor ability because reductions RCM have obvious disadvantages (i.e., decreasing fecundity) only partially improve speed endurance. Comparisons performance behaviors female garter snakes (Thamnophis ordinoides) before after parturition indicate declines change gestation. Females tend toward cryptic behavior than after. These observations are consistent with shifts observed lizards periods reduced abi...