Phylogenetic relationships near the origin of crown birds

Crane et al 2025 sought to clarify phylogenetic relationships
near the origin of crown birds by looking at mandibular morphology.

To long-time readers, this focus on just a few traits around the mandible sounds like “Pulling a Larry Martin.” Better to employ traits from mandible to tail and toes in any analysis… and employ more taxa than necessary.

Since this was an article ‘in press’
that means feedback is encouraged. So I wrote to the authors:

You wrote: “We find that evidence from Asteriornis fails to support interpretations of derived mandibular similarities with palaeognaths, and instead strongly favours galloanseran, and specifically galliform, affinities.”

This trait-based online cladogram supports that result:  http://reptileevolution.com/reptile-tree.htm …but does not recover the genomic clade Galloanseres. Instead chickens and their seed-eating allies nest far from water-tied geese and their allies, including Asteriornis.

You also wrote, “Our results also illustrate striking similarities in the architecture of the lower jaws between the toothed ornithurine Ichthyornis, Pelagornithidae and Vegavis, which, in addition to the absence of derived features linking them to Galloanserae, highlights questions regarding the phylogenetic position of these perennially controversial taxa.”

That same cladogram nests Pelagornis with Morus far from Ichthyornis. Vegavis nests among the most basal birds, close to Pseudocrypturus, again far from Ichthyornis.

The last common ancestor of crown birds in this trait-based cladogram is Early Cretaceous Archaeorhynchus. That gives almost the entire Cretaceous for birds to diversify and radiate across closer continents, despite the current paucity of supporting fossils. That’s how we get terror birds in South America derived from African secretary birds. That’s how we get highly derived New Zealand penguins in the Paleocene. That’s how we get ratites in all the former Gondwanaland continents. That’s how we get flightless kiwis restricted to New Zealand with their closest trait-based relatives, the woodcock and snipe, radiating elsewhere.

Hope this helps.
Best regards,
David Peters

To long-time readers
this comment on their paper represents the scientific method. The authors’ analysis was repeated using the LRT, but with the addition of more taxa and more characters. Results differed. That’s all you need to say. That gives the authors guidance with a suggested method. It’s up to them to add characters and taxa.

Note: I did not strip down the LRT to exactly repeat their experiment with just mandibular characters. That would be like taking away the steering wheel and gas tank from an automobile and expecting it to continue to work the same way. I am surprised that such a stripped down experiment focused on just the mandible was proposed let alone executed and submitted.

Editors note: I see I have four comments waiting in the queue. I have not looked at them, nor will I do so for a day or three while I work elsewhere on other issues. Apologies for the delay. Thank you for your patience.

References
Crane et al (4 co-authors) 2025. Mandibular morphology clarifies phylogenetic
relationships near the origin of crown birds. BMC Ecology and Evolution Article in Press. https://doi.org/10.1186/s12862-025-02487-4