Department of Biology, College of Life Science, Xinyang Normal University, Xinyang, SD, 464000, China.
Sci Rep. 2020 Apr 22;10(1):6838. doi: 10.1038/s41598-020-63635-y.
Life history theory predicts that animals often produce fewer offspring of larger size and indicate a stronger trade-off between the number and size of offspring to cope with increasing environmental stress. In order to evaluate this prediction, we tested the life history characteristics of Bufo minshanicus at eight different altitudes on the eastern Tibetan Plateau, China. Our results revealed a positive correlation between female SVL and clutch size or egg size, revealing that larger females produce more and larger eggs. However, high-altitude toads seem to favor more offspring and smaller egg sizes when removing the effect of female SVL, which is counter to theoretical predictions. In addition, there was an overall significantly negative relationship between egg size and clutch size, indicative of a trade-off between egg size and fecundity. Therefore, we suggest that higher fecundity, rather than larger egg size, is a more effective reproductive strategy for this species of anuran living at high-altitude environments.
生活史理论预测，动物通常会产生较少的大型后代，并表明在数量和大小之间存在更强的权衡，以应对日益增加的环境压力。为了验证这一预测，我们在中国东部青藏高原的八个不同海拔高度测试了华西蟾蜍的生活史特征。我们的研究结果表明，雌性 SVL 与窝卵数或卵大小之间呈正相关，这表明较大的雌性产生更多和更大的卵。然而，当去除雌性 SVL 的影响时，高原蟾蜍似乎更倾向于产生更多的后代和更小的卵大小，这与理论预测相反。此外，卵大小和窝卵数之间存在整体显著的负相关关系，表明卵大小和繁殖力之间存在权衡。因此，我们认为，对于生活在高海拔环境中的这种蛙类来说，更高的繁殖力而不是更大的卵大小是一种更有效的繁殖策略。
