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Re: Wollemi, Attenborough, and Branagh
T. Michael Keesey wrote:
I've seen fossil araucarian leaves from sites near the Lark Quarry dino
footprint locality in Winton Shire, central Queensland, and was told
that these leaves were conspecific with the Wollemi Pine. An age of 90
Ma sounds about right for that sort of locality...there are plenty of
other araucarian leaf types from the same set of localities, so
diversity of that family is already good at that time, even locally.
Now a question comes into my mind. Is this much ado about nothing? I see the
fossil record for these creatures (yes, the pines) being touted as either
ending 2 Ma ago or 90 Ma (I guess this last one must be a misprint). Is
there in fact a fossil record for Wollemia nobilis or are we talking of
Araucariaceae in general? I agree it's a wonderfull find, a living one at
that, but I'd like to have a bit of perspective thrown in to this "frenzy"
(if asking for that isn't too off topic).
From what I can glean, the *first* fossil record of the _Wollemia
nobilis_ stem-lineage is dated at 90Ma, and the split from other
extant _Araucariaceae_ would have been about 200Ma.
By the way, in response to a related question in this thread, 'pine' is
commonly used in ANZ to denote living species of araucarias - hence
Norfolk Pine, Hoop Pine, Bunya Pine, and the famous Kauri (spelling?)
Pine - so it seems perfectly natural to use the name in relation to
_Wollemia_. Pinus radiata, in contrast, is known as the Canberra
One interesting thing about them is that there has not been any
genetic variation detected between specimens. It seems that each one
is a virtual clone of each other one, despite the fact that they
reproduce sexually. This lack of genetic diversity might indicate that
it is a true "living fossil", with modern representatives being
virtual clones of more ancient representatives (how ancient, I don't
That's what I got from reading half a dozen websites today, anyway.
Corrections are welcome.
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