George Frandsen has been collecting ancient poop for many years. Now, he wants to share these exceptional excrements with the world in the first-ever online museum of fossilised poop: the Poozeum.

A coprolite from the Jurassic Period that was found in the United Kingdom. © George Frandsen/Poozeum

Coprolites are the fossilised remains of faeces, and they can come from any ancient species, from termites to turtles to tyrannosaurs. Frandsen first encountered one in a fossil shop in Utah during his freshman year of college. Amazed and immediately hooked, he bought the specimen – the first of a collection that continues to grow to this day.

What's so great about old poop? Coprolites are pretty rare as fossils go, and they can be valuable sources of information for scientists. Many of the specimens in Frandsen's collection include bits of bones and scales, the undigested remains of an animal's prehistoric dinner. Finding food in fossilised faeces is one of the only ways palaeontologists can show definitively what a particular prehistoric animal ate. Want to know what was on the menu for a hungry dinosaur? Check the poop! 

Despite their value, Frandsen found that coprolites got little attention in natural history museums or internet resources. So a few years ago, he decided to use his collection as the basis for an online museum. "[I want it to be] a free, one-stop, media-filled coprolite resource site," he says. 

This specimen was found in northwest Nebraska and one coprolite even shows the complete toe bone from a small deer in the genus Leptomeryx© George Frandsen/Poozeum

In 2015, Guinness World Records, with the help of professional palaeontologists, certified Frandsen's collection as the largest private coprolite collection in the world, containing over 1,200 samples at the time. According to Frandsen, thousands more have been added since then. 

The Poozeum holds some pretty incredible specimens, including the largest coprolite in the world – affectionately known as "Precious", it's 20 centimetres long and weighs almost two kilograms. Precious was probably left behind by a similarly supersized pooper, perhaps a large crocodilian.

Another standout specimen in Frandsen's collection (this one, unfortunately, doesn't have a name) bears the marks of large teeth, a sign of "aborted coprophagy": at one point in time, a big, hungry animal had snapped up the poo, chewed on it and spat it back out (wouldn’t you?). 

This is “Precious”, the famous coprolite. The specimen would be over 254mm or 10” inches long if it wasn’t bent. © George Frandsen/Poozeum
This coprolite shows evidence of aborted-coprophagy. Of all the coprolites known from the fossil record, this is the only specimen recognized as preserving both the top and bottom sets of vertebrate bite mark impressions. © George Frandsen/Poozeum

Frandsen's coprolites make public appearances, too. Recently on display at the South Florida Museum, the exhibit proved so popular it was extended from just a few months to an entire year.

Why are people so intrigued by fossilised poop? For Frandsen, the answer is quite simple. "It's something we can all relate to," he says. What's more, seeing the poop ancient animals left behind provides us with a connection to them, especially everyone's favourite prehistoric fascination, the dinosaurs. But it's also a subject we don't normally spend time on, and that makes it "fresh, exciting and maybe even a little taboo," he adds.

A coprolite found in South Dakota. © George Frandsen/Poozeum
This specimen dates back to the Miocene Epoch and shows signs of Invertebrate burrows throughout. © George Frandsen/Poozeum
A coprolite found in Germany. © George Frandsen/Poozeum
A coprolite from Wyoming that dates back at least 50 million years. © George Frandsen/Poozeum
This large fossilised faeces specimen is named "The Kraken". © George Frandsen/Poozeum

Correction: A previous version of this article incorrectly stated that Frandsen's collection is the largest coprolite collection in the world. In fact, it is the largest private coprolite collection in the world.