CRETACEOUS NEORNITHINES

[darren.naish@port.ac.uk]

Mike Keesey asked stuff about Mesozoic neornithine birds. Obviously 
you'd need all the literature to hand to go through these properly; I 
can't do that but I'd like to add some comments (apologies if these 
issues have been addressed already). The Hornerstown Formation birds  
[_Anatulavis_, _Tytthostonyx_ et al.] are, after all, probably 
latest Cretaceous as mosasaurs and some other K taxa are known from 
the site. This I learnt from Tom Stidham who posted his thoughts, via 
John Hutchinson, on dino-l a while back (in response to my assertion 
that, as Feduccia (1996) and others state, the Hornerstown is 
Palaeocene). Apparently there is published pollen data supporting a 
Palaeocene age, however, so loathe as I am to suggest that mosasaurs 
survived into the Cainozoic, there still might be some disagreement.

The Hell Creek parrot jaw described by Stidham and suggested to have 
affinities with loriids has not been accepted by the majority of 
ornithologists. Several authors - I will not mention their names but 
see if you can guess - have stated that it simply can't be a parrot 
because, well, it can't. Because of its antiquity I suppose. Gareth 
Dyke and Gerald Mayr have been working on early parrot evolution, 
mostly new specimens from Messel and the London Clay, and they argued 
in a response to Stidham that the jaw most probably was _not_ from a 
parrot: fossils show that the advanced parrot jaw is restricted to 
psittacids (=psittacoids), the psittaciform crown-group, and these 
did not evolve until the Oligocene or Miocene. Eocene parrots with 
complete skulls do not have psittacid-style jaws and in cladistic 
analyses are basal to psittacids. Of course, this still leaves the 
problem as to what the Hell Creek specimen IS and Stidham responded 
to Dyke and Mayr that, regardless of their arguments, all he had done 
was propose an identity based on morphological characters. Personally 
I think it unlikely that crown-group modern-style parrots were around 
in the Cretaceous: this would invoke long ghost lineages both for 
this group and for the Eocene parrots that are apparently basal to 
modern parrots. 

All of this was covered in _Nature_ to which you should refer for the 
full story; there is additional stuff in dino-l archives and, if you 
are interested in reading up on early parrot evolution and phylogeny, 
there are a number of papers by Mayr and in press (Dyke and Mayr). I 
think the refs for these are in the archives somewhere.

"The Japanese have a saying for this.. visitors are like fish, after 
3 days they start to stink"

DARREN NAISH 
PALAEOBIOLOGY RESEARCH GROUP
School of Earth, Environmental & Physical Sciences
UNIVERSITY OF PORTSMOUTH
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