Department of Biological and Environmental Science, University of Jyväskylä, Jyväskylä, Finland.
Department of Biological and Environmental Science, University of Jyväskylä, Jyväskylä, Finland.
J Insect Physiol. 2019 Jul;116:77-89. doi: 10.1016/j.jinsphys.2019.04.004. Epub 2019 Apr 17.
Selection experiments offer an efficient way to study the evolvability of traits that play an important role in insects' reproduction and/or survival and to trace correlations and trade-offs between them. We have exercised bi-directional selection on Drosophila montana flies' pre-adult development time under constant light and temperature conditions for 10 generations and traced the indirect effects of this selection on females' diapause induction under different day lengths, as well as on the body weight and cold tolerance of both sexes. Overall, selection was successful towards slow, but not towards fast development. However, all fast selection line replicates showed at the end of selection increased variance in females' photoperiodic diapause response and about one hour increase in the critical day (CDL), where more than 50% of emerging females enter diapause. Indirect effects of selection on flies' body weight and cold-tolerance were less clear, as the flies of the slow selection line were significantly heavier and less cold-tolerant than the control line flies after five generations of selection, but lighter and more cold-tolerant at the end of selection. Changes in females' diapause induction resulting from selection for fast development could be due to common metabolic pathways underlying these traits, collaboration of circadian clock and photoperiodic timer and/or by the interaction between the endocrine and circadian systems.
选择实验提供了一种有效的方法来研究在昆虫繁殖和/或生存中起重要作用的特征的可进化性，并追踪它们之间的相关性和权衡。我们在恒定的光照和温度条件下对黑腹果蝇的幼体发育时间进行了 10 代的双向选择，并追踪了这种选择对不同日长下雌蝇滞育诱导的间接影响，以及对两性的体重和耐寒性的影响。总的来说，选择是朝着缓慢的方向进行的，但不是朝着快速的方向进行的。然而，所有快速选择线的复制在选择结束时都表现出雌蝇光周期滞育反应的方差增加，以及临界日（CDL）增加约 1 小时，超过 50%的新出现的雌蝇进入滞育。选择对苍蝇体重和耐寒性的间接影响不太明显，因为在选择的第五代，慢选线的苍蝇比对照线的苍蝇重得多，耐寒性也差得多，但在选择结束时，苍蝇的体重更轻，耐寒性也更强。快速发育选择导致的雌性滞育诱导的变化可能是由于这些特征的共同代谢途径、生物钟和光周期定时器的协作，或者是内分泌和生物钟系统之间的相互作用。
