On Baminornis

Baminornis zhenghensis by uncredited artist.

A study has found a derived avialan from the Late Jurassic (Tithonian) of China. This bird solidifies the presence of pygostylian birds some 20 million years before other pygostylians show up in the fossil reccord. The phylogenetics on the study aren’t clear, but they favour a placement in Avialae just outside Jeholornis, meaning it could have developed its derived features independently… or Jeholornis is an atavistic fuck.

This has strong ramifications for the evolution of birds. Birds with modern features, even if not directly related to modern birds, were around in the Late Jurassic (though a possible enantiornithean has also been dated to the Jurassic), and contrast the “primitive” archaeopterygids and anchornithids that previously thought to represent birds in this epoch. Though given the weird bat-winged scansoriopterygids, it’s clear diversification and experimention were already pretty wild before the Jurassic ended.

Co-existing with these birds were pterosaurs, including “archaic” long tailed forms like rhamphorhynchids. This further disproves the notion that birds outcompeted pterosaurs, since modern birds were co-existing with even basal pterosaurs and co-existed with their cohorts for several tens of millions of years.

Ultimately the fossil reccord doesn’t capture biodiversity perfectly, and “modern” birds could have evolved even earlier.

Certainly a major breakthrough in our understanding of bird evolution.