In either instance, the elicited behaviors result in the following: (1) precopulatory mate guarding, wherein the male physically carries the female beneath his abdomen for several days before female ecdysis; (2) actual copulation immediately following ecdysis; and (3) postcopulatory
guarding until the female integument is sufficiently calcified (Fig.
Sperm competition is an important evolutionary driver in postcopulatory
sexual selection, which occurs in polyandrous species when the sperm of different males compete for the access to the ova (Parker 1970; Birkhead & Moller 1998; Parker & Pizzari 2010).
sexual selection in Mediterranean fruit flies: advantages for large and protein-fed males.
However, to date, no study has demonstrated postcopulatory
choice of male song through differential investment.
, prezygotic isolation in flour beetles.
It is well known that mammalian sperm has a higher water permeability than other cell types (Nodes et al., 1993; Curry et al., 1995a), and ion channel-controlled water influx/efflux is involved in postcopulatory
sperm volume regulation (Petrunkina et al., 2004; Yeung et al., 2005; Callies et al., 2008).
Retreat may be observed in pangolins as a precopulatory or postcopulatory
behaviour in response to the opposite sex individual.
"This provides experimental evidence that male genital morphology influences success in postcopulatory
reproductive competition," Polak said.
This suggests that the risks of competition are minimal, in contrast to what occurs in Scarabaeus, Kheper and Canthon, whose use of ephemeral resources has encouraged both precopulatory and postcopulatory
genital grooming in male rats: prevention of sexually transmitted infections.
Adaptive significance of postcopulatory
guarding of mates
Recently, Eberhard and Cordero (1995) have tried to extend the role of sexual selection to seminal products that might influence female reproductive behavior and physiology as well as to female postcopulatory
mechanisms for male discrimination (cryptic mate choice).