Departments of Botany and Forest and Conservation Sciences, University of British Columbia, Vancouver BC V6T 1Z4, Canada; African Centre for DNA Barcoding, University of Johannesburg, Johannesburg South Africa.
Department of Mathematics, Simon Fraser University, Burnaby BC V5A 1S6, Canada.
Curr Biol. 2024 Feb 26;34(4):R120-R125. doi: 10.1016/j.cub.2023.12.027.
Seed masting, a reproductive strategy characterized by variable and synchronous investment in reproduction among years, has attracted much attention. Masting trees incur a cost in delayed reproduction, and thus masting requires an ecological or evolutionary explanation. The two broad causal mechanisms to explain seed masting are resource availability and economies of scale (EOS); the former assumes reproductive investment simply covaries with environment, the latter suggests an adaptive advantage. Two of the most commonly proposed EOS for masting are predator satiation and pollination efficiency. Here we suggest an additional EOS: pathogen escape. We borrow from the disease ecology literature to describe alternative models of pathogen-mediated masting. By comparing and contrasting their ecological dynamics, we show how predator satiation and pathogen escape may favour masting through similar mechanisms of mass-action interactions and temporal delays. However, pathogen- and predator-mediated dynamics may also diverge as a result of host epidemiological structure and the spatial scale of the interaction. We propose that pathogen escape should be considered among the list of putative mechanisms to help explain the many diverse observations of masting across space and phylogeny.
结实大爆发是一种繁殖策略，其特征是在年份之间的繁殖中存在可变且同步的投资。结实大爆发吸引了很多关注。结实大爆发的树木会在延迟繁殖方面付出代价，因此结实大爆发需要有生态或进化方面的解释。解释结实大爆发的两个广泛的因果机制是资源可用性和规模经济（EOS）；前者假设繁殖投资只是简单地与环境相关，后者则表明存在适应性优势。结实大爆发最常被提出的两个 EOS 是捕食者饱和和传粉效率。在这里，我们提出了另一个 EOS：病原体逃避。我们借鉴疾病生态学文献来描述由病原体介导的结实大爆发的替代模型。通过比较和对比它们的生态动力学，我们展示了捕食者饱和和病原体逃避如何通过大规模相互作用和时间延迟的类似机制来促进结实大爆发。然而，病原体和捕食者介导的动态也可能因宿主流行病学结构和相互作用的空间尺度而出现分歧。我们提出，病原体逃避应该被视为帮助解释在空间和系统发育上广泛观察到的结实大爆发的众多潜在机制之一。
