{
  "id": 6734624,
  "title": "Growth rate and yield are not constrained by a trade-off in microbes",
  "url": "https://urgent.news/2026/09/11/growth-rate-and-yield-are-not-constrained-by-a-trade-off-in-microbes",
  "topic": "finance",
  "section": "Finance & Markets",
  "published": "2026-09-11T00:00:00.000Z",
  "source": {
    "name": "bioRxiv",
    "slug": "biorxiv",
    "url": "https://www.biorxiv.org/content/10.64898/2026.09.08.750265v1?rss=1"
  },
  "original_language": "en",
  "account": "Traditional ecological theory suggests widespread trade-offs between organisms' growth, survival, and reproduction. Among these, the relationship between maximum intrinsic growth rate (r) and carrying capacity (K) is often highlighted as a crucial mechanism for species coexistence and biodiversity maintenance. To understand how r correlates with K in microbes, researchers analyzed over 70,000 microbial growth curves across numerous media conditions. The results revealed a strong positive correlation between r and K, contradicting the conventional expectation of a trade-off in life histories. This surprising phenomenon, referred to as a \"trade-up,\" can be explained by a model that assumes a non-zero maintenance cost for cells. The model predicts that this trade-up becomes more pronounced under stress conditions that lower growth rates. Empirical data supports this, showing that salinity stress intensifies the trade-up. The researchers also discovered that community assembly weakens but does not eliminate the positive r-K relationship. Interestingly, the study found that while there is a robust growth-yield trade-up between species, there is little to no such relationship within species. This is evident in single-gene knockout datasets from Escherichia coli and budding yeast. Overall, the findings suggest that the absence of a strong trade-off between growth rate and carrying capacity might be common across species, highlighting the significance of alternative trade-offs and coexistence mechanisms beyond the traditional r-K framework.",
  "summary": "Ecological theory traditionally posits widespread trade-offs in organismal growth, survival, and reproduction. One core trade-off is the relation between maximum intrinsic growth rate (r) and carrying capacity (K), proposed as a key mechanism explaining species coexistence and the maintenance of biodiversity. To quantify how r relates to K in microbes, we analyzed more than 70,000 microbial…",
  "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."
}