Lips Karen R
Department of Biology, University of Miami, 33124, Coral Gables, FL, USA.
Oecologia. 2001 Aug;128(4):509-518. doi: 10.1007/s004420100687. Epub 2001 Aug 1.
I studied spatial and temporal variation in reproductive activity of Hyla calypsa along a montane stream in south-central Costa Rica between 1991 and 1996. Maggots of drosophilid flies killed the greatest number of frog eggs, while mortality from other sources was random and unpredictable. Late-season increases in fly predation may select for high, early reproductive effort by the frogs. Female frogs in this population show intra-clutch and seasonal variation in egg diameter and seasonal variation in clutch size. There were no correlations between female size and egg or clutch parameters. Egg diameter varied more within a clutch than among clutches, suggesting that individual females were allowing for unpredictable environmental conditions or that the larval environment may be selecting for variation in propagule size. This species uses both bet-hedging and trade-offs between offspring size and number to maximize the chance of producing tadpoles. Future studies should determine the advantages of small and large hatchlings and whether these relate to environmental variation in the stream.
1991年至1996年间，我研究了哥斯达黎加中南部一条山间溪流沿岸的卡利普希拉雨蛙繁殖活动的时空变化。果蝇的蛆杀死了最多数量的蛙卵，而其他来源造成的死亡率则是随机且不可预测的。晚季果蝇捕食量的增加可能促使青蛙进行高投入的早期繁殖努力。该种群中的雌蛙在卵径上表现出窝内和季节变化，在窝卵数上表现出季节变化。雌蛙体型与卵或窝卵参数之间没有相关性。窝内卵径的变化比不同窝之间的变化更大，这表明个体雌蛙在适应不可预测的环境条件，或者幼虫环境可能在选择繁殖体大小的变异。该物种通过在后代大小和数量之间进行风险分摊和权衡，以最大化产生蝌蚪的机会。未来的研究应确定大小不同的幼体的优势，以及这些优势是否与溪流中的环境变化有关。
