Agnolin 2021 on Brontornis affinities (still excluding parrots and stinkbirds)

Yes, it’s massive taxon exclusion time again
as Agnolin 2021 tells us that Brontornis (Fig. 2) is a giant goose.

We’ve known since 2011
that Brontornis is closely related to Gastornis (Figs. 1, 2) the giant flightless parrot.  Derived from hoatzins first, then sparrows, then even more distantly from fowl (= chickens, pheasants, peacocks), these giant flightless, herbivorous birds have all the hallmarks (= characters) of Ara, the parrot (Fig. 1).

these taxa were excluded from Agnolin’s 2021 analysis, again.

Figure 1. Gastornis (=Diatryma) to scale with Ara the parrot (lower right).

Figure 1. Gastornis (=Diatryma) to scale with Ara the parrot (lower right).

Figure 3. Skulls of Gastornis, Brontornis and Ara, the scarlet macaw.

Figure 3. Skulls of Gastornis, Brontornis and Ara, the scarlet macaw.

Agnolin 2007
also considered Brontornis a giant goose (Anseriformes).

Agnolin 2021
wrote, “After few changes in the data matrix, Brontornis results as part of a clade composed by the giant anseriforms designated by Worthy et al. 2017 as Gastornithiformes. This result is in agreement with recent proposals that excluded Brontornis from phorusrhacoid cariamiforms (where it was traditionally nested) and included it among Anseriformes.”

“Finally, the nesting of Brontornis among herbivorous giant anseriforms, together with several aspects of its mandibular morphology reinforces previous thoughts that Brontornis was herbivorous in habits.”

Fowl, sparrows, hoatzin (= stinkbirds) and parrots are all also herbivorous.

Unfortunately Agnolin 2007, 2021 supports
the hypothesis that fowl and geese are closely related in a traditional genomic clade, Galloanseriformes (= chicken + geese). The large reptile tree (LRT, 1803+ taxa; subset Fig. x) does not support that relationship. Rather fowl and geese are widely separated in the LRT where fowl are in cyan (= bright light blue, Fig. x) and geese are in pale magenta (= pinkish purple Fig. x).

Figure 4. Subset of the LRT focusing on birds. Chongmingia is highlighted in yellow in the Scansoriopterygidae.

Figure 4. Subset of the LRT focusing on birds. Chongmingia is highlighted in yellow in the Scansoriopterygidae.

Taxon exclusion
will always come back to haunt/bite you (pick your own favorite cliché). Add taxa as a remedy for this malady. It works every time.

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