Bradford Michael J, Guerette Paul A, Roff Derek A
Department of Biology, McGill University, 1205 ave. Dr. Penfield, H3A-1B1, Montreal, QC, Canada.
Oecologia. 1993 Mar;93(2):263-267. doi: 10.1007/BF00317680.
We experimentally tested a series of hypotheses proposed by Masaki (1979, 1986) for the evolution of ovipositor length in crickets. Female crickets use the ovipositor to bury eggs in the soil, where it was hypothesized to protect their eggs from desiccation, cold and other disturbance. However, we found no effect of depth on the overwinter survival of eggs of three species of Nemobiinae. The probability of hatchlings reaching the soil surface was negatively correlated with depth documenting a significant cost to females laying eggs deep in the soil. Hatchling survival may be an important agent of selection on ovipositor length in habitats of different soil moistures. Hatchling survival in the soil was also correlated with body size, which may impose a constraint on egg-size fecundity trade-offs. Females of a bivoltine population of Allonemobius socius lay eggs at shallower depths when reared under summer compared to fall conditions and, therefore, may be able to respond to selection through behavioral plasticity when morphological adaptation is constrained by allometry.
我们通过实验检验了正树（1979年、1986年）提出的一系列关于蟋蟀产卵器长度进化的假说。雌性蟋蟀用产卵器将卵埋入土壤中，据推测这能保护卵免受干燥、寒冷和其他干扰。然而，我们发现深度对三种姬蟋亚科昆虫的卵越冬存活率没有影响。幼体到达土壤表面的概率与深度呈负相关，这表明雌性在土壤深处产卵会付出巨大代价。幼体存活率可能是不同土壤湿度栖息地中产卵器长度选择的一个重要因素。土壤中的幼体存活率也与体型有关，这可能会对卵大小与繁殖力的权衡形成限制。与秋季条件相比，在夏季饲养时，双季种群的社会异针蟋雌性会在较浅的深度产卵，因此，当形态适应受到异速生长的限制时，它们可能能够通过行为可塑性对选择做出反应。
