Date: Wed, 21 Jun 2000 09:45:07 +1000 From: Miguel de Salas <mm_de@postoffice.utas.edu.au> To: cp@opus.hpl.hp.com Message-Id: <aabcdefg1856$foo@default> Subject: Re: Amazon rainforest destruction is real! What a disaster!!!
>""One of the simple, but very important, facts is that
>the rainforests have only been around for between
>12,000 and 16,000 years. That sounds like a very long
>time but, in terms of the history of the earth, it's
>hardly a pinprick"".
Then how come I've isolated rainforest species fossils as part of whole
rainforest assemblages dating back to the Eocene?
Rainforests have been around for very, very long. What might have been
meant in any case is that much of what is currently the Amazon rainforest
was steppe and savannah during the height of the last glaciation, when the
climate was much drier. However, rainforest almost certainly survived in
the form of refugia in higher, wetter valleys in the eastern side of the
Andes.
It is pretty clear that most of the earth (Including, yes, Antarctica) was
covered in rainforest during wetter periods, including much of the
tertiary. In the Eocene, for example, Tasmania had just lost contact with
Antarctica and was situated at a latitude of 70-75 degrees south, within
the polar circle. This didn't preclude the existence of fully tropical
temperatures and high humidities, as reflected by the widespread rainforest
at the time.
So if we look at it from this timescale, we've already lost most of the
rainforest (which used to cover much of what is dry land), and should try
and keep what's left.
As you can see this type of discussion doesn't have much point. Depending
on what timescale you are referring to, rainforest may have covered much of
the earth or hardly been there at all.
What does it all have to do with CPs anyway?
Miguel de Salas
mailto://mm_de@postoffice.utas.edu.au
School of Plant Science,
University of Tasmania,
GPO Box 252-55, Hobart,
Tasmania, Australia, 7001.
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