Fossilized excrement is providing clues about which birds survived a mass extinction event. Tiny feathers trapped in the excrement are helping scientists understand why some birds made it through while others did not. The feathers are well-preserved and were found in the remains of a bird that was eaten and then excreted by a predator, possibly a Tyrannosaurus rex.

The discovery was made in a study published in the journal Current Biology. It sheds light on the events leading up to the mass extinction that occurred 66 million years ago.

Further details about the study and its findings are available, including information about the exceptionally well-preserved feather found in the fossilized excrement.