Alford Ross A
Department of Zoology, Duke University, 27706, Durham, NC, USA.
Oecologia. 1986 Jan;68(2):199-204. doi: 10.1007/BF00384787.
Four sibships of Hyla chrysoscelis larvae were used to examine the effects of parentage on mass at day 23 of growth and on vulnerability to predation. The H. chrysoscelis larvae were raised alone, in competition with Rana clamitans larvae, and in competition with siblings. Vulnerability to predation by adult Notophthalmus viridescens dorsalis was evaluated for Hyla that had been raised in competition with siblings. Sibships differed in body mass and vulnerability to predation. Competition with Rana or with siblings resulted in a major reduction in body mass. There were no interactions between the effects of parentage and level of competition on body mass. Vulnerability to predation by newts appeared to be determined partially by body mass and partially by parental influences on factors other than body mass. If the differences observed between factors determining body mass and vulnerability to predation reflect negative genetic correlations among these determinants, tradeoffs between selection for increased competitive ability and reduced vulnerability to predators may partially account for the existence of genetic variation for growth rate in larval Hyla.
使用四窝金线蛙（Hyla chrysoscelis）幼虫来研究亲本关系对生长第23天的体重以及对捕食易感性的影响。金线蛙幼虫单独饲养、与绿蛙（Rana clamitans）幼虫竞争饲养以及与同胞竞争饲养。对于与同胞竞争饲养长大的金线蛙，评估其被成年东部绿红东美螈（Notophthalmus viridescens dorsalis）捕食的易感性。不同窝的幼虫在体重和捕食易感性方面存在差异。与绿蛙或与同胞竞争导致体重显著下降。亲本关系和竞争水平对体重的影响之间没有相互作用。被蝾螈捕食的易感性似乎部分由体重决定，部分由亲本对体重以外因素的影响决定。如果在决定体重和捕食易感性的因素之间观察到的差异反映了这些决定因素之间的负遗传相关性，那么在选择提高竞争能力和降低被捕食者捕食的易感性之间的权衡可能部分解释了金线蛙幼虫生长速率遗传变异的存在。
