{
  "id": 3275758,
  "title": "Song divergence and a gleaming white iris reveal four species in a widespread Neotropical understory bird (Clibanornis rubiginosus, Furnariidae)",
  "url": "https://urgent.news/2026/08/25/song-divergence-and-a-gleaming-white-iris-reveal-four-species-in-a",
  "topic": "science",
  "section": "Science",
  "published": "2026-08-25T00:00:00.000Z",
  "source": {
    "name": "bioRxiv",
    "slug": "biorxiv",
    "url": "https://www.biorxiv.org/content/10.64898/2026.08.24.746896v1?rss=1"
  },
  "original_language": "en",
  "account": "The Ruddy Foliage-gleaner, a widespread Neotropical understory bird belonging to the family Furnariidae, has been found to consist of four distinct species. This discovery arises from a closer examination of their songs, which had previously been overlooked due to the bird's large range and numerous subspecies.\n\nClibanornis rubiginosus, which spans from Mexico to Brazil, was originally recognized as a polytypic species with 15 subspecies. However, recent research has revealed that eight of these subspecies west of the Andes share a single-note song, while Amazonian and Guianan populations sing longer, lower-pitched songs with a short introductory note. Within this latter group, the subspecies watkinsorum sings the lowest-pitched and longest song, and is genetically closer to another species, C. cinnamomeigula, than to its Amazonian neighbors.\n\nThe third group consists solely of C. cinnamomeigula, a white-eyed taxon in an otherwise dark-eyed group. Its high-pitched, vibrato song is unique within the genus and does not share similarities with any other species. The remaining two-note song patterns are distinct and absent intermediates, indicating that every two-note taxon sequenced to date belongs to one clade. Consequently, this suggests that C. rubiginosus is paraphyletic and requires further classification.\n\nBy recognizing four separate species—C. rubiginosus sensu stricto, C. cinnamomeigula, C. watkinsorum, and C. obscurus—the classification of Clibanornis has been expanded from five species to eight. This new understanding highlights the importance of analyzing individual song characteristics to better understand the true diversity present within a widespread Neotropical bird species.",
  "summary": "Polytypic species with large ranges may harbor unrecognized diversity because taxonomy ranks populations differing subtly in plumage as subspecies. The Ruddy Foliage-gleaner (Clibanornis rubiginosus) exemplifies this problem. It ranges from Mexico to Brazil, with 15 subspecies, and forms a non-monophyletic complex with two congeners, yet its songs had not been compared. We measured ten spectral…",
  "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."
}