Everybody poops, as the saying goes—and sometimes, it sticks around for millions of years.
Such fossilized feces—called coprolites—can often help scientists determine what an ancient critter ate.
Take the giant ground sloth, whose poop (pictured below) revealed a diet of leaves, bark, and twigs, according to the Smithsonian Institution, which recently featured the dung in the their ”weekly peek” at museum collections.
Giant ground sloth dung
Photo courtesy Chip Clark, Smithsonian’s National Museum of Natural History
The hundred thousand-year-old poop (now on display at the National Museum of Natural History) was collected by Smithsonian curator Remington Kellogg in 1941 in the Grand Canyon. Giant ground sloths, relatives of living tree sloths, used their huge claws to grasp tree climbs and scrape bark off trees about 2.58 million years ago.
In addition to unearthing clues about a creature’s diet, ancient poop can give us other clues about the past.
In 2009, for instance, scientists announced the discovery of the oldest human hair—found in a piece of hyena poop. Researchers discovered the rock-hard dung near South Africa‘s Sterkfontein caves, where many early human ancestor fossils have been found.
The white, round fossil turds were found embedded in sediments 195,000 to 257,000 years old, we reported.
What’s more, 14,300-year-old fossilized human feces found in Oregon provided scientists with the earliest evidence of people in North America, according to a 2008 study.
That coprolite “looks like a hardened clump of brown mud of a, uh, familiar shape,” David Wolman wrote for National Geographic News.
As Wolman pointed out, coprolites are ideal objects for archaeologists to research, since studying other remains, such as bones, can be controversial.
“In contrast, no one takes offense to examining stool samples, which are filled with cellular material shed by the harsh environment of the colon,” Wolman wrote.
As University of Oregon archaeologist Dennis Jenkins said in the story, “You don’t think of it, but you’re leaving behind genetic signatures every morning.”
Check out more weird coverage on National Geographic News.