Housekeeping in the LRT: basal birds get corrected

Taking a critical look
at the basal bird subset of the large reptile tree (LRT, 1959+ taxa; Fig. 1) changes some tracings, some scores and some nestings. That’s why we call this a hypothesis of interrelationships. It’s a work in progress. It still needs several other workers to confirm it (or refute it, or parts of it) using substantially similar taxon lists.

More taxa brings more insight.
Mistakes should not be allowed to fester and when you’re dealing with new data not clearly presented (like crushed and scattered fossils), mistakes can happen. Making corrections is considered good science here, one of the benefits to online publishing, rarely seen in the world of print.

A tiny Early Cretaceous bird with short legs
Cratoavis (Fig. 3), now nests basal to larger Early and Late Cretaceous birds with longer legs.

A long-legged Latest Cretaceous taxon lacking a skull
and several other parts, Vegavis, now nests with other long-legged basal birds.

A short-beaked Early Cretaceous taxon with robust wings,
Jianchangornis (Fig. 3), was re-scored the most. Now it nests with its look-alike, Early Cretaceous Eogranivora (Fig. 3).

Better and more complete data
was used to score Megapodius (Fig. 2), previously scored for only a few skull traits based on a photo with only a few bones presented. When better data comes around, use it. That new data on Megapodius started this whole ball rolling again.

With these four changes,
the Cretaceous toothed birds leading to Neornithes are no longer in the clade of crown birds. Instead, the LRT splits the Cretaceous birds into three smaller clades (Fig. 1). Megapode-like Early Cretaceous Longicrusavis (Fig. 3), is now the proximal outgroup taxon to the crown birds. That gives crown birds even more time (tens of millions of years) to diversify to the point of having Paleocene giant penguins.

Housekeeping should be an important aspect of good science.
Correcting errors (the count continues to climb past 150,000 or so over the last 11 years) is part of the process. On the other hand, and for reasons that continue to perplex and bemuse, omitting pertinent taxa to create the impression that invalid hypotheses should remain in textbooks is not good science. Even so it is considered more acceptable in academic circles.