Fossilized dinosaur poop yields first ancient feathers

Scientists in Montana discovered exquisitely preserved feathers inside a fossilized dinosaur coprolite, marking the first time feathers have been found in dinosaur poop.

Jingmai O’Connor of the Field Museum of Natural History in Chicago and colleagues used micro-CT scans to map the contents of the fossil, revealing the feathers belonged to an aquatic bird called a hesperonithiform.

The feathers included dense bristles potentially able to repel water like a pelican’s, and lightweight shafts filled with air pockets, features previously unseen in dinosaur-age plumage. Researchers believe the feather structure might explain why some ancient birds survived the extinction event 66 million years ago while others, like the hesperonithiforms, did not. The more primitive, stringy feathers could have provided insufficient insulation, making the bird vulnerable to the cooling temperatures following the asteroid impact.

O’Connor hopes this discovery will encourage more paleontologists to search for feathers within coprolites, as fossilized feathers are rare and this finding demonstrates that dung can preserve them well.