Maternal egg care enhances hatching success and offspring quality in an oviparous skink

Maternal egg-caring behavior can often be observed in oviparous scincid lizards.The expression of such behavior is predictably affected by the trade-off between its resultant costs and benefits for mothers and/or offspring,which has been investigated in only a few scincid species.Here,post-ovipositional Plestiodon chinensis females were treated to care for their egg clutches without interference,under simulated predation pressure,or to be caredeprived.Potential maternal costs and offspring benefits associated with egg-caring behavior were then evaluated by measuring changes in maternal body condition,egg mortality,and hatchling performance.Egg-caring behavior caused post-ovipositional females to participate less in outside-nest activity,eat less food,and show relatively poorer body conditions at egg hatching.By contrast,compared with care-deprived females,egg-caring females gained mass slightly faster,and achieved a similar body condition within a few months of hatching.Eggs that were cared for by their mothers were more likely to hatch and produced larger,faster-running and better-growing hatchlings with higher survival than uncared-for eggs.Simulated exposure to a potential predator had no distinct impact on maternal egg-caring behavior expression and offspring performance.These results indicated that marked benefits of offspring viability but minor maternal energy costs might play a decisive role in the occurrence of maternal egg-caring behavior in P.chinensis.