Hadfield Jarrod D, Reed Thomas E
Institute of Evolutionary Biology, School of Biological Sciences University of Edinburgh Edinburgh EH9 3JT UK.
School of Biological, Earth and Environmental Sciences University College Cork, Distillery Fields North Mall Cork T23 N73K Ireland.
Evol Lett. 2022 Feb 28;6(2):178-188. doi: 10.1002/evl3.279. eCollection 2022 Apr.
The mismatch between when individuals breed and when we think they should breed has been a long-standing problem in evolutionary ecology. Price et al. is a classic theory paper in this field and is mainly cited for its most obvious result: if individuals with high nutritional condition breed early, then the advantage of breeding early may be overestimated when information on nutritional condition is absent. Price at al.'s less obvious result is that individuals, on average, are expected to breed later than the optimum. Here, we provide an explanation of their non-intuitive result in terms of hard selection, and go on to show that neither of their results are expected to hold if the relationship between breeding date and nutrition is allowed to evolve. By introducing the assumption that the advantage of breeding early is greater for individuals in high nutritional condition, we show that their most cited result can be salvaged. However, individuals, on average, are expected to breed earlier than the optimum, not later. More generally, we also show that the hard selection mechanisms that underpin these results have major implications for the evolution of plasticity: when environmental heterogeneity becomes too great, plasticity is selected against, prohibiting the evolution of generalists.
个体实际繁殖时间与我们认为其应有的繁殖时间之间的不匹配，一直是进化生态学中一个长期存在的问题。普赖斯等人的论文是该领域的一篇经典理论文章，主要因其最明显的结果而被引用：如果营养状况良好的个体较早繁殖，那么在缺乏营养状况信息时，较早繁殖的优势可能会被高估。普赖斯等人不太明显的结果是，平均而言，个体预计会比最优繁殖时间更晚繁殖。在这里，我们从硬选择的角度对他们这个非直观的结果给出了解释，并进而表明，如果繁殖日期与营养之间的关系能够进化，那么他们的两个结果都不会成立。通过引入这样一个假设，即营养状况良好的个体较早繁殖的优势更大，我们表明他们最常被引用的结果可以得到挽救。然而，平均而言，个体预计会比最优繁殖时间更早繁殖，而不是更晚。更一般地说，我们还表明，支撑这些结果的硬选择机制对可塑性的进化具有重大影响：当环境异质性变得过大时，可塑性会被选择淘汰，从而阻止通才的进化。
