{
  "id": 6533282,
  "title": "Cyclic pathogen epidemics favour the evolution of delayed germination",
  "url": "https://urgent.news/2026/09/09/cyclic-pathogen-epidemics-favour-the-evolution-of-delayed-germination",
  "topic": "science",
  "section": "Science",
  "published": "2026-09-09T00:00:00.000Z",
  "source": {
    "name": "bioRxiv",
    "slug": "biorxiv",
    "url": "https://www.biorxiv.org/content/10.64898/2026.09.04.749465v1?rss=1"
  },
  "original_language": "en",
  "account": "Delayed germination is a well-known strategy employed by plants to hedge against environmental variability. By delaying the emergence of offspring, plants can mitigate the risk of establishment across years that exhibit varying conditions such as temperature, precipitation, and other factors critical to seedling survival. While the role of biotic interactions in shaping germination timing has been explored less, this study investigates the evolutionary dynamics of germination timing in a host-pathogen framework. In this model, a saturating (Holling Type II) transmission function links seed bank dynamics to the recurrent cycles of pathogen epidemics.\n\nThe researchers identified three primary ecological outcomes using their model: a pathogen-free equilibrium, a stable endemic state, and an oscillatory endemic regime brought about through a bifurcation, signifying a transition from stable to oscillatory dynamics. Through adaptive dynamics, or invasion analysis, the study revealed that the optimal germination rate depends on the prevailing ecological regime. When the pathogen dynamics stabilize into an equilibrium, selection favors accelerated germination, with no upper limit to the rate, irrespective of the pathogen's impact. Conversely, when the dynamics manifest as periodic cycles, these regular epidemic peaks yield recurring periods of heightened establishment mortality, functioning as analogous selective pressures to abiotic factors like environmental conditions. The evolutionary optimum thus aligns with a critical bifurcation point.\n\nSimulations demonstrating trait substitution confirm the convergence towards this attractor, and multi-trait eco-evolutionary simulations provide compelling evidence that this attractor is evolutionarily stable, fitting the criteria for a continuously stable strategy (CSS). These findings broaden the classical bet-hedging theory to encompass biotic drivers, highlighting that pathogens with the capacity to sustain population cycles may exert an underrecognized selective influence on germination timing and, more broadly, on the tempo of life-history evolution.",
  "summary": "Delayed germination is classically explained as a bet-hedging strategy against environmental variability: by withholding a fraction of seeds from germination, plants spread establishment risk across years that vary in temperature, precipitation, and other conditions governing seedling survival. Whether biotic interactions can generate analogous selective pressure has received comparatively little…",
  "key_points": [],
  "editors_take": null,
  "illustration": null,
  "coverage": {
    "outlets": 1,
    "also_reported_by": []
  },
  "ai_generated": true,
  "disclaimer": "Summaries, key points and the editor’s take are written by software from other outlets’ reporting and may contain errors — always check the linked original."
}