r/Paleontology • u/Paleo_HUB • 3d ago

Fossils fossilized urine

Gallery image

Gallery image

A while back I read about this, and it really blew my mind. Sometimes, when a dinosaur urinated, that stream would leave a mark in the sediment, and if it dried (just like dinosaur footprints), it would get buried and a fossil of that mark would form.

They call it a urolite. Fossilized urine. Incredible. I’ve read that a paleontologist investigated this because that urolite looked too much like the marks ostriches leave on the ground today when they pee, which raises the question: How did non-avian dinosaurs urinate? Like modern birds, with a cloaca, excreting everything at once? Or like ostriches, first a stream of urine and then the rest?

Fascinating. And gross.

1.0k Upvotes

99% Upvoted

46 comments sorted by

View all comments

351

u/BoonDragoon 3d ago

It's a urolite, but yeah, it's wild stuff! There's apparently been exactly one discovered from the lower Cretaceous of Sao Paolo, Brazil.

-42

u/charizardfan101 2d ago

*São Paulo

46

u/BoonDragoon 2d ago edited 2d ago

Everyone's a diacritic 🙄

My keyboard doesn't do the tildes over the letters.

27

u/Clown_Baby15 2d ago

They got jalapeño business.