{
  "id": 3791827,
  "title": "Predation by migratory birds shapes seasonally fluctuating selection on a sexually selected signal",
  "url": "https://urgent.news/2026/08/27/predation-by-migratory-birds-shapes-seasonally-fluctuating-selection",
  "topic": "science",
  "section": "Science",
  "published": "2026-08-27T00:00:00.000Z",
  "source": {
    "name": "bioRxiv",
    "slug": "biorxiv",
    "url": "https://www.biorxiv.org/content/10.64898/2026.08.24.746656v1?rss=1"
  },
  "original_language": "en",
  "account": "Sexually selected traits can have fitness costs, but the benefits and drawbacks of such traits can change over time and location, leading to variations in selection on those traits. Insects are one group of organisms for which seasonal shifts in the abundance of migratory insect-eating birds can influence selection on these traits. The smoky rubyspot damselfly (Hetaerina titia) is an example of an insect with a notable seasonal variation in wing pigmentation across North America. The pigmentation is more conspicuous in summer-bred individuals.\n\nThis study investigates whether this variation in wing pigmentation is an adaptive response to seasonal and geographic changes in predation risk. The researchers first found evidence that strong constraints exist on wing phenotypes outside of the summer season, suggesting a seasonal shift in the balance of costs and benefits associated with pigmentation. They then conducted a nationwide predation experiment, which revealed that predation risk varies with wing pigmentation and is linked to the seasonal fluctuations in the local abundance of migratory birds.\n\nThe findings demonstrate an ecological and evolutionary connection between tropical and temperate regions, emphasizing the need to consider the evolutionary and ecological implications of spatial and temporal fluctuations in biotic interactions as species distributions change due to global change.",
  "summary": "Sexually selected traits often impose fitness costs on their bearers. Yet, the relative costs and benefits of conspicuous traits can vary through space and time, driving variation in selection acting on those traits. For insects, an important but overlooked source of such variation is seasonal shifts in the local abundance of migratory insectivorous birds. Smoky rubyspot damselflies (Hetaerina…",
  "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."
}