Overview
- Researchers published a Current Biology paper on Sept. 10, 2026 reporting scans of a golf‑ball‑size coprolite found in 2016 in Montana’s Hell Creek Formation.
- Micro‑CT imaging revealed multiple 3D feathers, tiny gar fish scales, and small leg bones preserved inside the coprolite without breaking it open.
- The bones and associated remains match a hesperornithiform diving bird, and the team infers the feathers came from that bird, recording a gar → bird → theropod food chain.
- Two feather types were identified: modern‑like, water‑repellent wing feathers and primitive, fluffy body feathers, prompting a hypothesis that insulation differences affected survivorship after the asteroid impact.
- Authors call for systematic CT scanning of museum coprolites to test this idea but note key inferences remain provisional and the coprolite producer (e.g., Tyrannosaurus rex or Nanotyrannus) is not confirmed.