If we mean Avialae (closer to Aves than Deinonychus), I'd say the earliest known are the trio of scansoriopterygids Ambopteryx, Scansoriopteryx (= Epidendrosaurus) and Epidexipteryx, from the Bathonian-Callovian Haifanggou and Jiulongshan Formations. Even
if troodontids, unenlagiids and/or archaeopterygids/anchiornithids are also avialans, these have them all beat except that Pedopenna would tie the record if its an archaeopterygid.
Mickey Mortimer
From: dinosaur-l-request@mymaillists.usc.edu <dinosaur-l-request@mymaillists.usc.edu> on behalf of Thomas Richard Holtz <tholtz@umd.edu>
Sent: Tuesday, April 27, 2021 5:14 AM To: Yazbeck, Thomas <yazbeckt@msu.edu> Cc: dinosaur-l@usc.edu <dinosaur-l@usc.edu>; Poekilopleuron <dinosaurtom2015@seznam.cz> Subject: Re: [dinosaur] What is the earliest known bird Do not forget Asteriornis, a crown-bird from the Maastrichtian of Belgium (depending on the dating of
Vegavis it may be younger than the Antarctic bird, or at the same age.)
If you mean "Avialae", then Archaeopteryx loses out to the Oxfordian-aged Tiaojishan Formation forms like
Anchiornis (which most recent phylogenies agree is also more closer to modern birds than to dromaeosaurids).
The vernacular "bird" is so arbitrary, though: do you mean Aves? Ornithurae? Euornithes? Ornithothoraces? Pygostylia? Avialae? Eumaniraptora? Pennaraptora?
On Tue, Apr 27, 2021 at 2:42 AM Yazbeck, Thomas <yazbeckt@msu.edu> wrote:
Thomas R. Holtz, Jr. Office: Geology 4106, 8000 Regents Dr., College Park MD 20742 Dept. of Geology, University of Maryland Phone: 301-405-6965 Office: Centreville 1216, 4243 Valley Dr., College Park MD 20742 8000 Regents Drive |