The oldest human hairs ever found have been discovered embedded in ancient hyena coprolites.
Lucinda Backwell, a paleontologist in the group, took a sediment block containing several coprolites back to the lab for a closer look. She and a colleague carefully removed forty of the “hairs apparent” from one of the coprolites and subjected half to scanning-electron microscopy. Sure enough, fossilized hairs they were, and five showed remarkably preserved surface scales.
Comparing the scales to those of a variety of animals – an admittedly tricky undertaking – Backwell’s team concluded that human hairs were the best match.