It’s just a little dumpling. I don’t know what else to call it. The baby, this most tragic and precious little thing, is curled up tight as if still inside a leathery shell that decayed away more than 251 million years ago. The protomammal perished before it was even born but I still want to hold it in my palm and offer it everything.

I’ve never seen a fossil quite like this one. It was exciting enough, back in 2018, when paleontologist Eva Hoffman and colleagues described dozens of Kayentatherium babies. The small bones represented the first protomammal perinates anyone had ever uncovered. Their size, apparent helplessness, and number all suggested that their parent stayed nearby and raised them on milk. But these Lystrosaurus embryos, they tell a very different story for one of the most resilient species that’s ever existed.

Lystrosaurus doesn’t look like an especially close relative of ours. The animal had a turtle-like beak flanked with tusks, its form often likened to a reptile-like pig. Still, if we follow the family tree, Lystrosaurus is more closely related to us than to any reptile, one of the many forms of protomammals that thrived in the Permian world of more than 252 million years ago. When an especially terrible mass extinction ground down the majority of known vertebrate species alive at the end of the Permian, Lystrosaurus was one of the few survivors. The protomammal even seemed to thrive in the shaken, struggling Triassic world. Why this animal? What made Lystrosaurus so special? The dumplings embody an important clue.