Evolutionary transition to birds on YouTube video

https://www.youtube.com/watch?v=GV49b9RFCRw

Transformations… the complex evolutionary transition to birds by Dr Corwin Sullivan.

@7:40 Sullivan’s cladogram divides Archosauria into Pseudosuchia and Ornithodira. Adding taxa recovers a clade Archosauria containing only Crocodylomorpha + Dinosauria and does not recover Pseudosuchia, nor Ornithodira. The latter traditionally includes Pterosauria, but those were shown to be lepidosaurs related to Huehuecuetzpalli and small bipedal tanystropheids like Sharovipteryx, Longisquama and Cosesaurus almost 20 years ago (2000, 2007). In this new order Ornithodira is a junior synonym for Reptilia and so is Amniota.

@8:18 Sullivan reports the origin of birds from theropods has been widely accepted for three decades = since 1990 (on this 2016 video). This points out a major fault with paleontology: failure to embrace the obvious. By 1996 Ostrom’s work with Archaeopteryx and Deinonychus was, by then, twenty years old and Huxley’s advocacy for the transitional status of feathered Archaeopteryx was over a century old.

@9:00 Sullivan fails to acknowledge the variety of Solnhofen birds, labeling them all Archaeopteryx, which has become a brand name, unfortunately, more valuable to lump than to separate.

@9:57 Sullivan shows several feathered theropods, labeling them all ‘first-cousins’ and ‘close’ to birds. This is incorrect. Many theropods unrelated to birds also had feathers. Sullivan more or less acknowledges this fact later.

@14:46 Sullivan discusses scansoriopterygids as closely related to birds. After analysis these are birds, some of them secondarily flightless, which Sullivan later reports.

@15:23 Sullivan brings up microraptors, which are convergent with birds, not closely related after analysis. Cladogram here: http://reptileevolution.com/reptile-tree.htm

@21:00 Yi qi does not have a strange wing. Rather that was a misinterpretation of a torsion fracture detailed here: https://pterosaurheresies.wordpress.com/2021/07/04/when-a-simple-torsion-fracture-turned-an-early-cretaceous-bird-into-bizarre-bat-wing-dinosaur/

Which brings up another widespread weakness in paleontology: a failure to test odd interpretations and resulting ‘unique’ concepts like the styliform element. So Sullivan is promoting a myth here. He wonders why this theropod had membraneous wings when no others do. That should have led him and others to figure out why this element was misinterpretated.

@28:38 Sullivan moves on to the rib cage and other elements associated with flight – completely ignoring the key to flapping: the elongate, locked-down coracoid found in birds and pterosaurs. Bats substitute an elongate, locked-down clavicle since they lack a coracoid. Non-avian theropods have a short, round, sliding coracoid. Flapping preceeded flying and gliding in birds. This insight has been overlooked and ignored by avian paleontologists, other than Ken Dial (2003).