Briddon Charlotte Louise, Menéndez García Aurora, Ghedini Giulia
GIMM - Gulbenkian Institute, Lisbon, Portugal.
Department of Biology, Ghent University, Ghent, Flanders, Belgium.
Proc Biol Sci. 2025 Jul;292(2050):20251146. doi: 10.1098/rspb.2025.1146. Epub 2025 Jul 9.
Species can evolve rapidly in response to competition but how evolution within communities affects community properties is unclear. Niche theory predicts that species should evolve to use different resources, increasing coexistence and community productivity. However, recent experiments suggest that species might instead evolve their competitive ability, particularly when competing for essential resources. To test the consequences of species evolution on community properties, we grew three species of marine phytoplankton in monoculture (alone) or polyculture (together) for 4.5 months. We then combined them in communities based on their competition history and tracked community composition and productivity over time. We found that species dominance was unaffected, but coexistence was reduced when species evolved together (polyculture isolates). These species-level changes did not affect community functions equally. Total biovolume growth rates and carrying capacity were the same between communities of monoculture or polyculture isolates but the latter had greater oxygen fluxes during the exponential phase. Our results suggest that evolution within communities can strengthen competitive differences between species with uneven effects on community functioning. While some community properties seem robust to species evolutionary changes, we should be cautious in extrapolating the consequences of evolution from community biomass to other aspects of productivity or stability.
物种能够对竞争做出快速进化，但群落内部的进化如何影响群落特性尚不清楚。生态位理论预测，物种应进化以利用不同资源，从而增加共存和群落生产力。然而，最近的实验表明，物种可能反而会进化其竞争能力，尤其是在争夺基本资源时。为了测试物种进化对群落特性的影响，我们将三种海洋浮游植物单独培养（单种培养）或混合培养（混种培养）4.5个月。然后，我们根据它们的竞争历史将它们组合成群落，并随时间跟踪群落组成和生产力。我们发现，物种优势不受影响，但当物种一起进化时（混种培养分离株）共存性降低。这些物种水平的变化对群落功能的影响并不相同。单种培养或混种培养分离株的群落之间总生物量生长率和承载能力相同，但后者在指数期有更大的氧气通量。我们的结果表明，群落内部的进化可以强化物种间的竞争差异，对群落功能产生不均衡的影响。虽然一些群落特性似乎对物种进化变化具有抗性，但我们在将进化的后果从群落生物量外推到生产力或稳定性的其他方面时应谨慎。
