In case you were wondering, the NYTimes has a TMI article regarding dinosaur anatomy...
[HEADING=2]Finally in 3-D: A Dinosaur’s All-Purpose Orifice[/HEADING]
This cloaca is more than 100 million years old, and it did a lot of work for this extinct species.
The world’s oldest known all-purpose orifice sits in a fossil display case in the Senckenberg Natural History Museum in Frankfurt, Germany, so close to the glass that enshrines it that you can “put your face up to it, like this,” said Jakob Vinther, a paleontologist at the University of Bristol in England, holding his hand a couple inches from his nose.
It belongs to a Psittacosaurus, a beaked, dog-size, leaf-munching dinosaur that lived more than 100 million years ago. And it’s not technically an anus, even though it sometimes functioned like one. It’s a cloaca: a multifunctional outlet named for the Latin word for “sewer,” through which some animals — including a menagerie of modern birds, reptiles, amphibians and even a few mammals — can defecate, urinate, copulate and/or extrude their offspring or eggs.
Now, that orifice’s opening, which was flattened during its fossilization, has been reconstructed into a three-dimensional model and [published Tuesday in the journal Current Biology]('https://www.cell.com/current-biology/fulltext/S0960-9822(20)31891-1'). Close examination of the Psittacosaurus’s prehistoric privates suggest that the cloaca is somewhat crocodilian, but is still distinct among known nether regions.
“It’s always kind of a rare gift when we get soft tissues like this preserved,” said Armita Manafzadeh, a vertebrate paleontologist at Brown University who was not involved in the study.
In case you want to read the whole thing, here it is: [Finally in 3-D: A Dinosaur’s All-Purpose Orifice]('https://www.nytimes.com/2021/01/19/science/dinosaur-cloaca-fossil.html?surface=home-discovery-vi-prg&fellback=false&req_id=173493866&algo=identity&variant=no-exp&imp_id=964912796&action=click&module=Science%20%20Technology&pgtype=Homepage')
