Gibbs Theo L, Levine Jonathan M, Turcotte Martin M
Lewis-Sigler Institute for Integrative Genomics, Princeton University, Princeton, New Jersey, USA.
Department of Ecology and Evolutionary Biology, Princeton University, Princeton, New Jersey, USA.
Ecology. 2025 May;106(5):e70085. doi: 10.1002/ecy.70085.
The competitive effect of one individual on another can have impacts beyond just reductions in performance. Because species plastically respond to their environment, competition can also induce changes in species traits, and in turn, these modified traits can then affect interactions with yet other individuals. In this context, plasticity is often argued to favor species coexistence by increasing the niche differentiation between species, though experimental evidence for this hypothesis that explicitly projects competitive outcomes is largely lacking. Here, we transiently subjected four annual plant species to early-season intraspecific or interspecific competition to explicitly induce plastic responses and then examined the response of these individuals to competitors faced later in life. Competing with nearby individuals early in the growing season tended to amplify the sensitivity of individuals to competition, and particularly so for interspecific competition, but the strength of this effect depended on the identity of the focal species. This increase in interspecific relative to intraspecific competition caused plasticity to decrease the predicted likelihood of pairwise coexistence. By combining recent theory with a new experimental approach, we provide a pathway toward integrating phenotypic plasticity into our quantitative understanding of coexistence.
一个个体对另一个个体的竞争效应可能产生的影响不仅仅是性能下降。由于物种会对其环境产生可塑性反应，竞争还会引发物种性状的变化，反过来，这些改变的性状又会影响与其他个体的相互作用。在这种情况下，可塑性通常被认为通过增加物种间的生态位分化来促进物种共存，尽管在很大程度上缺乏明确预测竞争结果的这一假设的实验证据。在这里，我们让四种一年生植物物种短暂地经历早期种内或种间竞争，以明确诱导可塑性反应，然后研究这些个体对后期遇到的竞争者的反应。在生长季节早期与附近个体竞争往往会增强个体对竞争的敏感性，种间竞争尤其如此，但这种效应的强度取决于焦点物种的身份。种间竞争相对于种内竞争的这种增加导致可塑性降低了成对共存的预测可能性。通过将最新理论与一种新的实验方法相结合，我们提供了一条将表型可塑性纳入我们对共存的定量理解的途径。
