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We are, by now, used to hearing how volant/semi-volant dinosaurs may
have evolved into large-bodied grounded descendants. Reversals and
adaptations for large size may have made some groups, such as certain
theropods, exhibit features more 'primitive' than those seen in their
ancestors. The hands of phorusrhacoids are a superb example.
Other possible instances of reversal are seen in large flightless
geese which, in ways, resemble supposedly primitive palaeognathous
birds like ratites. Regardless, the birds are interesting anyway.
This recently came out..
JAMES, H.F. and BURNEY, D.A. 1997. The diet and ecology of Hawaii's
extinct flightless waterfowl: evidence from coprolites. _Biological
Journal of the Linnean Society_ 62: 279-297.
Coprolites preserved with unfortunate Moa-nalo (aka Turtle-jawed
geese) of taxon _Thambetochen chauliodous_ (unfortunate because the
birds that produced the coprolites fell into, and became trapped in,
Puu Naio Caves) show that they were eating ferns before their death.
I was thinking that this fact may show that the birds were eating
what was available, i.e. they could not select plants they really
wanted to eat, but 'If birds that took their last meal outside the
cave had eaten something different from birds that fed within the
cave, we might expect the microfossil spectra to be more
heterogeneous' (p. 290). So - - fern eating geese! Wow.
Some moa-nalo (genera _Thambetochen_ and _Ptaiochen_) have
pseudoteeth, and _Chelychelynechen_ had broad, flat occlusal surfaces
forming crushing platforms.
It's funny that the James and Burney paper should appear now, as at
about the same time, this one came out..
WORTHY, T.H., HOLDAWAY, R.N., SORENSON, M.D.
and COOPER, A.C. 1997. Description of the first complete skeleton of
the extinct New Zealand goose _Cnemiornis calcitrans_ (Aves:
Anatidae), and a reassessment of the relationships of _Cnemiornis_.
_Cnemiornis_ was also a flightless big herbivore, and its robust
square-tipped bill indicates that it was a grazer. The specimen
described in this paper is the first pretty much complete skeleton
The cladistic analysis of Worthy et al. shows that _Cnemiornis_ is
most closely related to _Cereopsis_: the Cape Barren goose, something
long suspected and reasonably logical if you compare the two with
each other and other anatids. A proverbial spanner in the works is
Livezey's 1989 study: he even doubted that _Cnemiornis_ was an anatid
and gave its own family, deemed more basal in Anseriformes than
Anatidae. However, both _Cereopsis_ and _Cnemiornis_ share unique
derived characters, and DNA analysis supports a relationship between
them, exclusive of other birds.
"I was very sceptical.. I thought, Hong Kong !NA!.. having lived out