myllokunmingia

Eons Roundup 13

I haven’t posted any PBS Eons commissions here for quite a while, so let’s catch up a bit of the backlog:

An illustration of the extinct mammal Repenomamus robustus. It's a low-slung, stocky, badger-like animal with a thick tail, depicted as colored brown and white. It's shown baring a mouth full of pointed teeth. — *Repenomamus robustus*

An illustration of the extinct mammal Repenomamus giganticus. It's a low-slung, stocky, badger-like animal with a thick tail, depicted as colored yellow-brown and dark brown. It's shown walking with its head held down as if stalking something. — *Repenomamus robustus*

The Cretaceous mammals Repenomamus robustus and Repenomamus giganticus, from “When Mammals Only Went Out At Night”
https://www.youtube.com/watch?v=JqZONKXWPfw

An illustration of a decaying carcass of the extinct whale Borealodon. Its skin is tattered and torn as if scavengers have been picking at it, and part of its lower jaw bone is exposed. — *Borealodon osedax* (carcass)

A carcass of the whale Borealodon, from “How Ancient Whales May Have Changed the Deep Ocean”
https://www.youtube.com/watch?v=1vb00-gcdtA

An illustration of the extinct early vertebrate Haikouichthys. It's a small eel-like animal with large eyes, a circular mouth, and seven gill slits. It's depicted as pale blue colored, and it's swimming in dark blue water. — *Haikouichthys ercaicunensis*

And the early vertebrates Haikouichthys and Myllokunmingia, from “Why Sour May Be The Oldest Taste”
https://www.youtube.com/watch?v=XXgd_cNZSvk

Myllokunmingia, from the Early Cambrian of China (~530 mya).

Just under 3cm long (or just over 1″), this tiny animal seems to have been a very close relative of the true vertebrates – almost a vertebrate itself but not quite there yet. A single known fossil specimen shows evidence of a cartilage skull and skeletal elements, five or six gill pouches, a large sail-like dorsal fin, and paired finfolds on its underside.