No early gender effects on energetic status and life history in a salmonid.

Throughout an organism's early development, variations in physiology and behaviours may have long lasting consequences on individual life histories. While a large part of variation in critical life-history transitions remains unexplained, a significant proportion may be caused by early gender effects as part of gender-specific life histories shaped by sexual selection. In this study, we investigated the presence of early gender effects on the timing of emergence from gravel and the energetic status of brown trout (Salmo trutta) early stages. To investigate this question, individual measures of emergence timing, metabolic rate and energetic content were coupled for the first time with the use of a recent genetic marker for sdY (sexually dimorphic on the Y-chromosome), a master sex-determining gene. Our results show that gender does not influence the energetic content of emerging juveniles or their emergence timing. These findings suggest that gender differences may appear later throughou...在生物体的早期发育阶段，生理与行为的差异可能对个体生活史产生持久影响。尽管目前仍有大部分关键生活史转变的差异尚未得到合理解释，但其中相当一部分可能源于早期性别效应——即由性选择塑造的性别特异性生活史的组成部分。本研究以褐鳟（Salmo trutta）早期发育阶段个体为研究对象，探究早期性别效应对其从砾石巢中出巢时间以及能量状态的影响。为解答该研究问题，本研究首次将出巢时间、代谢速率与能量含量的个体水平测定数据，与新近开发的针对sdY（Y染色体性别二态性基因，主控性别决定基因）的遗传标记相结合。本研究结果显示，性别并不会对出巢幼体的能量含量或出巢时间产生影响。上述发现表明，性别差异可能在后续发育阶段逐步显现……