{
  "id": 7683895,
  "title": "Decadal signatures of seasonal and ENSO-driven selection in microbial populations in distant oceans",
  "url": "https://urgent.news/2026/09/15/decadal-signatures-of-seasonal-and-enso-driven-selection-in-microbial",
  "topic": "science",
  "section": "Science",
  "published": "2026-09-15T00:00:00.000Z",
  "source": {
    "name": "bioRxiv",
    "slug": "biorxiv",
    "url": "https://www.biorxiv.org/content/10.64898/2026.09.14.751425v1?rss=1"
  },
  "original_language": "en",
  "account": "Microbes in distant ocean regions exhibit seasonal and ENSO-driven selection, as revealed by a decade-long study of coastal marine microbiomes. The Blanes Bay Microbial Observatory (BBMO) and the Microbes in the Coastal Region of Orange County (MiCRO) were examined, each with distinct oceanographic characteristics. Despite their geographic separation, 250 genomes shared 95% genome similarity between the sites, while only 13 BBMO genomes matched 15 MiCRO representatives at a stricter 99% similarity threshold. As genome similarity increased, the distribution shifted from cosmopolitan to more coastal strains, and genome size expanded slightly, indicating niche adaptation. Seasonal population structure was evident in ~70% of genomes, while ~76% of MiCRO genomes displayed El Nino Southern Oscillation (ENSO)-associated structure beyond seasonal effects. A Prochlorococcus genome shared by both locations exhibited recurrent seasonal mutations and a higher positive selection signal during ENSO events. These findings suggest that long-term climatic oscillations play a significant role in shaping microbial populations, providing valuable insights into how the ocean microbiome may respond to future environmental changes.",
  "summary": "Despite the crucial role of the ocean microbiome for global ecosystem processes, its response to global change remains poorly understood. Global change will exert selection on microbial species through changes in the genetic composition of their populations, favouring strains that are better adapted to new conditions. Analyzing long-term genomic variation in microbial populations inhabiting…",
  "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."
}