Shine Richard, Downes Sharon J
Biological Sciences A08, University of Sydney, NSW 2006, Australia e-mail:
Oecologia. 1999 Apr;119(1):1-8. doi: 10.1007/s004420050754.
We exposed females of a highly placentotrophic viviparous scincid lizard (Pseudemoia pagenstecheri) to various environmental factors during pregnancy, and quantified the effects of these treatments on their offspring. The clear result was that the phenotypes of neonatal lizards can be substantially modified by the environment that their mother experiences during gestation. Restricting prey availability to the females reduced the size of their offspring. Limiting the females' basking opportunities delayed their seasonal timing of parturition, and modified body proportions (tail length relative to snout-vent length) of the neonates. More surprisingly, female lizards that were regularly exposed to the scent of sympatric lizard-eating snakes gave birth to offspring that were heavier, had unusually long tails relative to body length, and were highly sensitive to the odour of those snakes (as measured by tongue-flick responses). The neonates' antipredator responses were also modified by the experimental treatment to which their mother was exposed. The modifications in body mass, tail length and response to snake scent plausibly reduce the offspring's vulnerability to predatory snakes, and hence may constitute adaptive maternal manipulations of the neonatal phenotype.
我们在妊娠期让一种高度胎盘营养型胎生石龙子蜥蜴（佩氏石龙子）的雌性个体接触各种环境因素，并量化这些处理对其后代的影响。明确的结果是，新生蜥蜴的表型会因其母亲在妊娠期所经历的环境而发生显著改变。限制雌性个体的猎物可获取量会减小其后代的体型。限制雌性个体的晒太阳机会会延迟其季节性分娩时间，并改变新生蜥蜴的身体比例（尾巴长度相对于吻肛长度）。更令人惊讶的是，经常接触同域食蜥蜴蛇气味的雌性蜥蜴所产的后代更重，相对于体长而言尾巴异常长，并且对那些蛇的气味高度敏感（通过吐舌反应来衡量）。新生蜥蜴的反捕食者反应也会因其母亲所接受的实验处理而改变。体重、尾巴长度以及对蛇气味反应的改变可能会降低后代对捕食性蛇类的脆弱性，因此可能构成对新生表型的适应性母体操控。
