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Re: Waimanu & avian evolution (comments)

A long decline is important, but given the diversity of late Cretaceous
large-bodied pterosaurs (a diversity that was much higher than
previously thought, it now seems), I think the bolide would have to
remain pretty relevant.

Yes, and more importantly...
- Was there ever such a thing as a small adult pterosaur, anurognathids excepted, after the Early Jurassic? Adult *Rhamphorhynchus* spanned 2 m, *Pterodactylus* 2.5... I don't think this is properly counted in the paper, though I can't check right now.
- The fossil record of pterosaurs is quite bad. Where are tapejarids known from? Only from the best of the best (Santana & Crato Fms, Jiufotang Fm). Where are anurognathids known from? Only from the best of the best of the best (Karatau, Solnhofen, Yixian Fm). No sites of such quality are known from the Late Cretaceous. Clearly this must mean the potential sampling bias is impressive. ... Isn't there a toothed pterosaur jaw fragment from the Late Cretaceous of Rajasthan, India?

It depends on how you look at it.  Tail fans seem to be present in
neornithines prior to Falconiformes (likely back to ornithothoraces),

Sure, and its most common function seems to be the reduction of parasite drag, as shown by wind channel experiments. I'll dig up the paper (Proc. R. Soc. Lond. B 2003) ASAP.

but the raptorial armament was probably derived within the lineage.

Within Neornithes most of it is restricted to Falconiformes including Strigiformes...

On the other hand, the Avisauridae show at least some of those adaptations, and one of them comes from the Hell Creek Fm.

Of course, I would also love to hear everyone's thoughts regarding
the dated tree itself, which is ultimately the most important part of the
paper.

Interesting that no one here took up that challenge--or, did I miss it?

You didn't miss it; the challenge didn't draw any contenders.

Indeed. Part of the reason is that we know so little about neornithine phylogeny that we aren't capable of catching any glaring mistakes in the tree that might be obvious to everyone 5 or 10 years from now.