Niewiarowski Peter H, Dunham Arthur E
Department of Biology, Leidy Labs, University of Pennsylvania, Philadelphia, Pennsylvania, 19104-6018.
Evolution. 1994 Feb;48(1):137-145. doi: 10.1111/j.1558-5646.1994.tb01300.x.
We evaluated Shine and Schwarzkopf's (SS) model of the evolution of reproductive effort (RE) in squamate reptiles. They suggested that fecundity trade-offs were unimportant in the evolution of RE in most squamate reptiles and that only survival trade-offs needed to be considered. However, we show that by assuming no variation in offspring size exists, and that adult mortality is episodic, the results of the SS model are not general. By extension, we argue that conclusions drawn about factors important in the evolution of RE in squamate reptiles are premature. Using a modified version of the SS model, we demonstrate that variation in the form of trade-offs relating offspring size and survival substantially affect relationships among clutch size, relative clutch mass, and lifetime reproductive success. We also demonstrate that the way in which adult mortality is simulated drastically affects conclusions about the potential fecundity trade-offs experienced by populations of squamate reptiles. Finally, we suggest that a complete understanding of the evolution of RE will come from theory that incorporates trade-offs between offspring size and quality, as well as other system-specific constraints on the allocation of energy to growth, maintenance, storage, and reproduction.
我们评估了施奈德和施华蔻（SS）关于有鳞目爬行动物繁殖投入（RE）进化的模型。他们认为，在大多数有鳞目爬行动物的RE进化中，繁殖力权衡并不重要，只需考虑生存权衡。然而，我们表明，通过假设后代大小不存在变异，且成年死亡率是偶发性的，SS模型的结果并不具有普遍性。由此推论，我们认为关于有鳞目爬行动物RE进化中重要因素的结论为时过早。使用SS模型的一个修改版本，我们证明了与后代大小和生存相关的权衡形式的变异会显著影响窝卵数、相对窝卵质量和终生繁殖成功率之间的关系。我们还证明，模拟成年死亡率的方式会极大地影响关于有鳞目爬行动物种群潜在繁殖力权衡的结论。最后，我们建议，对RE进化的全面理解将来自于整合了后代大小与质量之间的权衡以及其他特定于系统的能量分配限制（如生长、维持、储存和繁殖）的理论。
