#hadrocodium

[vickysaurus-art]

Two Hadrocodium who have made their nest in a patch of moss on a tree are rudely disturbed by a curious snakefly. Meanwhile a Tatisaurus has developed a sudden craving for moss.

[synapsidgirl]

Instead of doing inktober this time, I’ve been doodling Sciartober prompts. Not all of them, and I started on day 11, got carried away with one of them, and I have no idea when I’m going to finish it, but here’s what I’ve done so far. So, day 11 - fish. Or in my case, a happy Castorocauda trotting home with a nice, big, juicy one. Day 17 - invisible. Hoplophoneus trying to dissapear from view. Day 18 - in the ocean. Basilosaurus, because of course it is . Day 19 - mammal. Fruitafossor, probably the earliest known relative of therian mammals. Day 20 - tiny. Hadrocodium, cause it tiny. It was an early Jurassic mammaliaform that was pretty cloe to crown group mammals. I kind of screwed up the thumb, and for some reason the shading looks much worse than it does in person. I also made two versions of this, but I decided to go with this one, because while I prefer the hand in the first on, it had really stark, dramatic light and shadow that detracted from the Hadrocodium. I should have predicted that drawing in a room lit only by small desk lamp will do that. I also managed to kill my back and left arm drawing these. Because of course I did.

[alphynix]

Month of Mesozoic Mammals #08: Tiny Transitional Hadrocodium

Falling evolutionarily between the docodonts and Mammalia itself, Hadrocodium is an important transitional form in the early mammal family tree. Something very similar to it would have been the common ancestor of all modern mammals.

Living in China during the Early Jurassic (196-189 mya), it was one of the first known mammals to have both an enlarged brain cavity and the characteristic middle ear bones of modern mammals, about 45 million years earlier than such traits were previously thought to have evolved.

It was also one of the smallest mammals of all time, measuring only about 3cm long (1.2″) -- similar in size to the smallest mammals alive today, the bumblebee bat and Etruscan shrew.

[data-and-vision]

[eximago-blog]

Hadrocodium wui is an extinct Mammaliaform from the lower Jurrasic of China. At a mere 1.35 inches (3.2 cm), it is one of the smallest "mammals" to have ever existed. Hadrocodium was an important discovery with interesting implications. It had evolved features that were though to define true mammals from their mammal-like ancestors. Relatively speaking, it had a large brain. It also had an advanced jaw structure and middle ear (the three tiny bones of which evolved from reptilian jaw bones). This shows that these features appeared a full 45 million years earlier than previously thought. It was also probably a warm-blooded, nocturnal insectivore.