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Re: No Cretaceous placental mammals?

On 6/22/07, K and T Dykes <ktdykes@arcor.de> wrote:

Unless I've been dating that attractive Miss Informed again, the last I heard was that the unambiguous Cretaceous fossil record for the 28? (or something like that) extant feathery fraternal orders, was closely comparable to the weight of seagull droppings on my car. As I haven't got a car, that would be less than one.

Then again, I think the most recent thing I happened to read on such
mammal-birdy matters was Benton MJ (1999), Early origins of modern birds and
mammals, molecules vs. morphology, BioEssays, 21, p.1043-1051.  Perhaps
details of the landscape might've changed over the past eight years, but I'd
be surprised to find an impressive nesting colony of such cases has
accumulated.  Still, a bit old or not, the paper's at least easily
accessible on-line.

So is Clarke et al. 2005: http://www.digimorph.org/specimens/Vegavis_iaai/nature03150.pdf

They find _Vegavis iaai_, a Maastrichtian bird from Antarctica, to be
a stem-anatid. This means, at the very least, that pan-palaeognathes,
pan-galliforms, pan-neoavians, pan-anhimids, pan-anatids, and the
_Anseranas_ total group were distinct before the K/Pg boundary. (Also
possibly the _Lithornis_ branch--or is _Lithornis_ considered a
palaeognathe now?)

Mike Keesey