Pascoal Sonia, Jarrett Benjamin J M, Evans Emma, Kilner Rebecca M
Department of Zoology University of Cambridge Cambridge CB2 3EJ United Kingdom.
Pembroke College Cambridge CB2 1RF United Kingdom.
Evol Lett. 2018 Mar 17;2(2):114-125. doi: 10.1002/evl3.45. eCollection 2018 Apr.
When females mate promiscuously, rival males compete to fertilise the ova. In theory, a male can increase his success at siring offspring by inducing the female to lay more eggs, as well as by producing more competitive sperm. Here we report that the evolutionary consequences of fecundity stimulation extend beyond rival males, by experimentally uncovering effects on offspring. With experiments on the burying beetle , we show that smaller subordinate males are better able to stimulate female fecundity than larger, dominant males. Furthermore dominant males also benefit from the greater fecundity induced by smaller males, and so gain from the female's earlier promiscuity - just as predicted by theory. By inducing females to produce more offspring on a limited resource, smaller males cause each larva to be smaller, even those they do not sire themselves. Fecundity stimulation thus promotes the non-genetic inheritance of offspring body size, and provides a mechanism for telegony.
当雌性进行滥交时,雄性竞争者会竞相使卵子受精。从理论上讲,雄性可以通过促使雌性产下更多卵子以及产生更具竞争力的精子来提高自己生育后代的成功率。在此我们报告,通过实验揭示对后代的影响,繁殖力刺激的进化后果不仅限于雄性竞争者。通过对埋葬虫的实验,我们发现较小的从属雄性比较大的优势雄性更能刺激雌性的繁殖力。此外,优势雄性也从较小雄性诱导的更高繁殖力中受益,从而从雌性更早的滥交中获利——正如理论所预测的那样。通过促使雌性在有限资源上产生更多后代,较小的雄性会使每个幼虫体型更小,即使是那些它们自己并未授精的幼虫。因此,繁殖力刺激促进了后代体型的非遗传继承,并为先父遗传提供了一种机制。