Re: chicken wing-claws

["David Marjanovic" <david.marjanovic@gmx.at>]

> I was surprised to learn that the hoatzin-seriema clade is not new.  Olson
> (1985) proposed a close relationship between the two groups, as part of a
> more inclusive Sth American neognath radiation.

I've just read the paper (heh heh... it was accessible, sort of!)...
apparently there are some mosaic birds from the Eocene of the Green River Fm
and Quercy that fit this interpretation.

> (Mayr and Clark [2003]
> regard a Musophagidae+Cuculidae [turacos+cuckoos, respectively] as sister
> taxon to the _Opisthocomus_-Cariamidae clade -

and the whole thing is in a "higher landbird" clade, far away from the
remaining "gruiforms", which populate the base of Neoaves.

> Anyway, if seriemas and hoatzins are closely related, then this clade
would
> have to include phorusrhacids.  At least one phorusrhacid (_Titanis_) has
a
> mobile manual digit (the first, I think), and juvenile hoatzins have free
> manual digits (so they can climb) - is this a potential synapomorphy for
> this clade?

Sounds like an interesting idea... more seriema research, please! :-)