Aquiloni Laura, Gherardi Francesca
Department of Animal Biology and Genetics, University of Florence, Via Romana 17, 50125 Florence, Italy.
Biol Lett. 2008 Apr 23;4(2):163-5. doi: 10.1098/rsbl.2007.0590.
To test whether male body size affects female reproductive investment in the polygamous crayfish Procambarus clarkii, we described mating behaviour of virgin females paired with either small or large males, and analysed the number, size and weight of both eggs and juveniles sired by either types of male. Along with confirming the overt selection by females of larger mates, we found that the size and weight of both the eggs and the juveniles were higher when sired by larger fathers. This suggests that P. clarkii females exert a form of cryptic choice for large males, seemingly adjusting the quantity of egg deutoplasm in function of the mate body size. The question of why females spend time and energy to brood low-fitness offspring is finally raised.
为了测试雄性体型是否会影响多配性克氏原螯虾雌性的生殖投入，我们描述了未交配过的雌性与小体型或大体型雄性配对后的交配行为，并分析了这两种类型雄性所产的卵和幼体的数量、大小及重量。在证实了雌性对体型较大配偶的明显选择之后，我们发现，由体型较大的雄虾授精的卵和幼体，其大小和重量都更大。这表明，克氏原螯虾雌性对大体型雄性表现出一种隐蔽选择形式，似乎是根据配偶体型来调整卵质的数量。最后，我们提出了一个问题，即为什么雌性要花费时间和精力去抚育适应性较差的后代。
