Hi Friends
I have just realised that there was some more information I should have
inlcuded in my Albatross paper. It is the influence of Ice Ages on
plumages. Don't forget at hat the last Ice Age ended about 11,000 years ago,
and its started about 23,000 BC. And Scientist now say that the Ice age
affected not only the Northern Hemisphere but also the Southern Hemisphere:
witness glaciation in the southern Andes. Global temperatures during the
coldest part of the Ice Age were between 3 and 9°C cooler then today, with
a most likely difference of about 5-6°C. If the taxa within the Dioedea
exulans complex on Amsterdam Island and the New Zealand Subantarctic Islands
at this time, the temperature would have been much lower than today. That
means feather lice, the main reason for adopting darker plaumage, would have
been far less of a problem. And I'll bet you that during that period, most
of the taxa that now breed in relatively warmer climates would probably have
looked like Diomedea exulans dabbenena. Don't forget that epigenetic effects
can kick in very quickly. The first realisation of epigentics cam from a
study tracing the health of people from the far north of Norway. And it was
found that if your great-grandfather was eight years old in a time of
relative famine, you could expect to live up to ten years longer than if
your great-grandfather was eight years old in a time of plenty. And I will
also bet that if most of the taxa resembled dabbenena, that there would have
been no rush to split them!
Dr John Penhallurick
86 Bingley Cres
Fraser A.C.T. 2615
Australia
email:
Phone: Home (612) 62585428
Mobile:0408585426
sunt lacrimae rerum et mentem mortalia tangunt Aeneid Book 1,line 462 "The
world is a world of tears, and the burdens of mortality touch the heart."
Magna est veritas et praevalet Vulgate, Book of Edras
The legitimate object of government is to do for a community of people
whatever they need to have done, but can not do at all, or can not so well
do, for themselves?in their separate, and individual capacities. Abraham
Lincoln
"It's good to look beyond the bounds of accepted ideas" James
Peebles,Princeton University
Please visit my website: http://www.worldbirdinfo.net
<http://www.worldbirdinfo.net/>
Please visit my blog:
http://jpenhall.wordpress.com/2011/04/02/john-penhalluricks-blog-1-evidence-
that-the-ipccs-case-is-a-fraud/
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