Ferrari R P, Martinelli R, Saino N
Dipartimento di Biologia, Università degli Studi di Milano, Milano, Italy.
J Evol Biol. 2006 May;19(3):981-93. doi: 10.1111/j.1420-9101.2005.01030.x.
In diverse animal taxa, egg mass variation mediates maternal effects with long-term consequences for offspring ontogeny and fitness. Patterns of egg mass variation with laying order differ considerably among birds, but no study has experimentally investigated the function of variation in albumen or yolk egg content in the wild. In barn swallows (Hirundo rustica), absolute and relative albumen mass increased with egg laying order. Experimental albumen removal delayed hatching, had larger negative effects on growth of late-hatched nestlings, and reduced nestling survival. Laying order positively predicted hatch order. Because nestling competitive ability depends on size, and albumen egg content influences hatchling size, present results suggest that by increasing albumen content of late eggs mothers reduce hatching asynchrony and enhance growth particularly of late-hatched nestlings. Thus, variation in albumen mass with laying order may function to mitigate the negative phenotypic consequences of hatching late in species that adopt a 'brood-survival' strategy.
在不同的动物类群中，卵质量的变化介导了母体效应，对后代个体发育和适合度产生长期影响。鸟类中，卵质量随产卵顺序的变化模式差异很大，但尚无研究在野外通过实验探究蛋白或卵黄含量变化的功能。在家燕（Hirundo rustica）中，蛋白的绝对质量和相对质量随产卵顺序增加。实验性去除蛋白会延迟孵化，对晚孵化雏鸟的生长有更大的负面影响，并降低雏鸟存活率。产卵顺序能正向预测孵化顺序。由于雏鸟的竞争能力取决于体型大小，且蛋白含量会影响雏鸟体型，目前的结果表明，通过增加后期卵的蛋白含量，母亲可减少孵化异步性，并特别促进晚孵化雏鸟的生长。因此，蛋白质量随产卵顺序的变化可能起到减轻采用“育雏存活”策略物种中晚孵化带来的负面表型后果的作用。
