Buongiorno, Anchiornis!

Added: 2026-05-19

[00:00:00]Angus and its relatives are little birdlike dinosaurs from the Jurassic of China, which we do not have a toy of, but their excellent fossils preserve both the skeleton and the soft bits, including the feathering and famously the coloration of the animal. The skeleton has much of the equipment that would be needed for flight, but the soft tissues, particularly the feathering, suggest that they were not using it for that. Laser stimulated fluoresence showed that the chest muscles are a slender sheet and they're not even anchoring to a breast bone, not even cartilage. So, the way they were moving clearly didn't rely on a downstroke.

[00:00:36]Modeling of these animals is borderline.

[00:00:38]They couldn't fly, but they couldn't rule out that they were flapunn.

[00:00:44]When it comes to the feet, the joints between the toes are not as hinge-like as we would expect in a perching animal.

[00:00:51]The claws of the feet don't have the strong curvature that we would associate with a climbing animal. And they don't have the sickles that we associate with, you know, droiosaur like predation. They do have large pads on the toes, which suggests an animal that was running along the ground preying on animals that also couldn't fly. We have stomach contents of lizards and fish. The feathering also bears this out.

[00:01:15]Anternids have a lot of it. both wing feathers, primaries and secondaries, and tail feathers, retrices. They are small, narrow, and nearly symmetrical. So, these wouldn't be very useful for flying. Like modern ryes or ostriches, the number of primary feathers varies between individuals. We find more primaries than the 9 to11 we count in volent or recently flightless animals.

[00:01:38]And in some of these, we get twice that.

[00:01:40]If antionids were like crown birds and the number of primaries and the arrangement of the coverts over those primaries was inflexible, that would suggest that Antionis was really far removed in time, tens of millions of years later than the ancestor of penaptors with its 9 to11 primaries, which would mean penoraptors first evolved in the early Jurassic, 15 to 20 million years earlier than we'd thought. Which again implies that there's forms out there that we have yet to discover.