Rebar Darren, Halliwell Chay, Kemp Rachel, Kilner Rebecca M
Department of Biological Sciences Emporia State University Emporia Kansas USA.
Department of Zoology University of Cambridge Cambridge UK.
Ecol Evol. 2022 Apr 15;12(4):e8829. doi: 10.1002/ece3.8829. eCollection 2022 Apr.
The overproduction of offspring is commonly associated with high hatching failure and a mechanism for dispensing with surplus young. We used experimental evolution of burying beetle populations to determine causality in these correlations. We asked does eliminating the mechanism for killing "spare" offspring cause the evolution of a more restrained clutch size and consequently select for reduced hatching failure? . typically overproduces eggs but kills 1 instar larvae through partial filial cannibalism during brood care. We established replicate evolving populations that either could practice filial cannibalism (Full Care) or could not, by removing parents before their young hatched (No Care). After 20+ generations of experimental evolution, we measured clutch size and hatching success. We found that No Care females produced fewer eggs than Full Care females when allowed to breed on a small corpse, a finding not explained by differences in female quality. On larger corpses, females from both populations laid similar numbers of eggs. Furthermore, hatching success was greater in the No Care populations on small corpses. Our results suggest that the adaptive overproduction of offspring depends on a mechanism for eliminating surplus young and that killing offspring, in turn, relaxes selection against hatching failure.
后代的过度繁殖通常与高孵化失败率以及一种处理多余幼崽的机制相关联。我们利用埋葬甲虫种群的实验进化来确定这些关联中的因果关系。我们提出疑问：消除杀死“多余”后代的机制是否会导致更克制的窝卵数的进化，从而选择降低孵化失败率？埋葬甲虫通常会过度产卵，但在育雏过程中通过部分同类相食杀死一龄幼虫。我们建立了可进行同类相食（全育雏）或不可进行同类相食（无育雏，即在幼崽孵化前移除亲代）的重复进化种群。经过20多代的实验进化后，我们测量了窝卵数和孵化成功率。我们发现，当在小尸体上繁殖时，无育雏的雌性产生的卵比全育雏的雌性少，这一发现无法用雌性质量的差异来解释。在较大的尸体上，两个种群的雌性产卵数量相似。此外，在小尸体上，无育雏种群的孵化成功率更高。我们的结果表明，后代的适应性过度繁殖依赖于一种消除多余幼崽的机制，而杀死后代反过来又会减轻对孵化失败的选择压力。
