Wade Michael J, Sultan Sonia E
Department of Biology, Indiana University, Bloomington, Indiana, USA.
Department of Biology, Wesleyan University, Middletown, Connecticut, USA.
Evol Dev. 2023 Nov;25(6):451-469. doi: 10.1111/ede.12452. Epub 2023 Aug 2.
Organisms construct their own environments and phenotypes through the adaptive processes of habitat choice, habitat construction, and phenotypic plasticity. We examine how these processes affect the dynamics of mean fitness change through the environmental change term of the Price Equation. This tends to be ignored in evolutionary theory, owing to the emphasis on the first term describing the effect of natural selection on mean fitness (the additive genetic variance for fitness of Fisher's Fundamental Theorem). Using population genetic models and the Price Equation, we show how adaptive niche constructing traits favorably alter the distribution of environments that organisms encounter and thereby increase population mean fitness. Because niche-constructing traits increase the frequency of higher-fitness environments, selection favors their evolution. Furthermore, their alteration of the actual or experienced environmental distribution creates selective feedback between niche constructing traits and other traits, especially those with genotype-by-environment interaction for fitness. By altering the distribution of experienced environments, niche constructing traits can increase the additive genetic variance for such traits. This effect accelerates the process of overall adaption to the niche-constructed environmental distribution and can contribute to the rapid refinement of alternative phenotypic adaptations to different environments. Our findings suggest that evolutionary biologists revisit and reevaluate the environmental term of the Price Equation: owing to adaptive niche construction, it contributes directly to positive change in mean fitness; its magnitude can be comparable to that of natural selection; and, when there is fitness G × E, it increases the additive genetic variance for fitness, the much-celebrated first term.
生物体通过栖息地选择、栖息地构建和表型可塑性等适应性过程构建自身的环境和表型。我们通过普莱斯方程的环境变化项来研究这些过程如何影响平均适应度变化的动态。在进化理论中，这一点往往被忽视，因为重点在于描述自然选择对平均适应度影响的第一项（费希尔基本定理中适应度的加性遗传方差）。利用种群遗传模型和普莱斯方程，我们展示了适应性生态位构建性状如何有利地改变生物体所遇到的环境分布，从而提高种群平均适应度。由于生态位构建性状增加了高适应度环境的频率，选择有利于它们的进化。此外，它们对实际或经历的环境分布的改变在生态位构建性状与其他性状之间产生了选择性反馈，尤其是那些在适应度上具有基因型与环境相互作用的性状。通过改变经历的环境分布，生态位构建性状可以增加此类性状的加性遗传方差。这种效应加速了对生态位构建的环境分布的整体适应过程，并有助于快速完善对不同环境的替代表型适应。我们的研究结果表明，进化生物学家应重新审视和重新评估普莱斯方程的环境项：由于适应性生态位构建，它直接促成平均适应度的正向变化；其大小可能与自然选择的相当；而且，当存在适应度的基因型与环境相互作用时，它会增加适应度的加性遗传方差，即备受赞誉的第一项。
