Yes (some) Dinosaurs did eat grass!

 Have a Happy Thought: 

 

I heard this week that dinosaurs didn’t eat grass, because grass **didn’t exist yet** at the time that the (non-avian) dinosaurs all died.

 

So, that blew my mind.

 

And I was going to tell you all this as the Friday email, but I’m dedicated to making sure that what I put in these is the truth. So I did some research. And it turns out that..

 

Grass DID exist before the (non-avian) dinosaurs all died! Not for too long, though, and not for the entire time dinosaurs were around – grasses evolved probably 70 million years ago (non-avian dinosaurs died out around 66 million years ago)… maybe as long as 100 million years ago. (Before grass was around, herbivorous dinosaurs were eating other plants like cycads and ferns. I might have to do a Friday email about cycads because they are so. cool.)

 

How do we know this?

 

Well, coprolites.

 

What are coprolites, you ask?

 

Fossilised dung.

 

Yep, scientists have looked into fossilised dinosaur poo, and found evidence that grass had been eaten and pooped out by actual dinosaurs. Turns out there’s a part of a plant cell, called a phytolith, that can survive digestion by a large animal. Phytoliths from different types of plants have different shapes, and apparently grass phytoliths are quite distinctive. And yep, you guessed it, these scientists found phytoliths that are specific to grasses inside the coprolites. (there’s your two new words of the week)

 

Science is awesome.

 

Oh also the existence of grass may explain the tooth shape of a gopher-size mammal called gondwanatherians, that also existed at the time the K-Pg (Cretaceous-Paleogene) boundary was created by a massive rock smashing into the Gulf of Mexico and creating what is now the Chicxulub Crater.

In case you needed a few Scrabble winners.

 

 

Thanks to @arvalis on twitter for giving me the reason to look into grass and dinosaurs.

And this NewScientist article for confirming grass in dinosaur dung.