Phenotypic variation in an oviparous montane lizard (Bassiana duperreyi): the effects of thermal and hydric incubation environments

Recent studies have shown that incubation temperatures can profoundly affec t the phenotypes of hatchling lizards, but the effects of hydric incubation environments remain controversial. We examined incubation-induced phenotyp ic variation in Bassiana duperreyi (Gray, 1938; Sauria: Scincidae), an ovip arous montane lizard from south-eastern Australia. We incubated eggs from t his species in four laboratory treatments, mimicking cool and moist, cool a nd dry, warm and moist, and warm and dry natural nest-sites, and assessed s everal morphological and behavioural traits of lizards after hatching. Incu bation temperature influenced a lizard's hatching success, incubation perio d, tail length and antipredator behaviour, whereas variation in hydric cond itions did not engender significant phenotypic variation for most traits. H owever, moisture affected incubation period slightly differently in males a nd females, and for a given snout-vent length moisture interacted weakly wi th temperature to affect lizard body mass. Although incubation conditions c an substantially affect phenotypic variation among hatchling lizards, the a bsence of strong hydric effects suggests that hatchling lizards react less plastically to variation in moisture levels than they do to thermal conditi ons. Thus, our data do not support the generalization that water availabili ty during embryogenesis is more important than temperature in determining t he phenotypes of hatchling reptiles. (C) 2001 The Linnean Society of London .