11 Things Fossil Dung Scientists Found in Fossilized Poop

Paleoscatologists have, quite possibly, the most epic job description ever: “fossil dung scientists.” Among the best-known is Kim Chin, who maintains that fossil feces—which are known scientifically as coprolites—can “teach us about the diet of ancient animals and how those animals interacted with each other” to an arguably greater extent than their celebrated skeletal remains. With that in mind, let’s examine a few items spotted in prehistoric poo.

1. Dinosaur Bones

Found in dung attributed to Tyrannosaurus rex; the bones belonged to a plant-eating species. According to Smithsonian, the amount of bone still left in the poop suggests that what the T. rex ingested didn't remain in its digestive system for long enough for it to break down; this is a marked difference from modern crocodiles and snakes. 

2. Louse Eggs and Human Hair

Found in 2000-year-old human feces. The egg was still attached to the hair. 

3. Tapeworm Eggs

Found in a 270-million-year-old shark coprolite that had been buried in a lakebed. According to National Geographic, "The density of the minifossils suggests that the eggs were part of a tapeworm body segment that breaks off and passes out of the body with feces, a standard part of the tapeworm life cycle that is still in place today. The strategy relies on some unlucky consumer coming along and eating the parasite-laden poop, giving the eggs a new home and starting the process anew."

4. Dung Beetle Burrows.

Found in numerous specimens spanning tens of millions of years.

5. Seeds

Found in ancient poop belonging to an extinct flightless Moa bird. Despite the fact that the bird was nearly 10 feet tall, most of the seeds came from plants that were under 2 feet tall. 

6. Shells

Found in human excrements dating to 2400 BCE.

7. Fish Scales

Found in numerous marine deposits from several geological periods. Here’s a handy link to a small sample from central Kansas.

8. Wood Fragments

Found in 83-million-year-old dinosaur droppings.

9. Spores

Found in material attributed to prehistoric arthropods.

10. Bacterial Colonies

Found in 90-million-year-old dinosaur dung (along with several other specimens throughout much of the fossil record).

11. Evidence of Pre-digestion.

Found in a 12,000-year-old Mammoth coprolite. “Mammoths Ate Their Own Poo” shouts a 2010 Discover magazine headline after tell-tale fungi samples revealed that at least some of these majestic mammals ingested their own fecal matter. Many modern species—including rats and elephants—do the same, in order to gain the most nutrition out of what they've already processed once.