From: bear@tigger.cs.Colorado.EDU (Bear Giles)
Subject: Re: Facts and Values (was Where it came from)
Organization: National Oceanic & Atmospheric Adminstration / Boulder Labs
Distribution: na
Date: Wed, 26 Aug 1992 22:18:14 GMT

In article <25786@dog.ee.lbl.gov> sichase@csa3.lbl.gov writes:
>In article <1992Aug26.192110.27466@colorado.edu>, bear@tigger.cs.Colorado.EDU (Bear Giles) writes...
>> 
>>I thought there was a _lot_ of evidence that early humans hunted many
>>other animals to extinction.  Bones in fire pits and the like.
>
>I doubt that it is easy to prove such a contention.  But even granted that it 
>is so, what are we talking about?  Two or three large mammals which were
>hunted to extinction?  A dozen?  A hundred?  This is nothing compared to
>the job we are doing right now.

Look at the niches, not the raw numbers.

Humans enter Europe and virtually all other large predators are eliminated.
Saber-tooth tigers, extinct.  Cave bears, extinct.  (The bears remaining
in Europe originated in Asia, but I don't know when they migrated).  Wolves
remained for awhile, but they were cross-bred with domesticated wolves
(which became dogs).  Lions apparently remained until early historical
times.

Large herbavores remained if they could be domesticated.  Mammoths could
not; they're extinct.  Cattle, sheep, goats and pigs could be domesticated
and they're still alive.  Deer were domesticated in the north (there are
no wild reindeer, for instance.  Every animal is owned) but not the south.
(I'm tempted to list 'elephants' as domesticated as a reference to Hannibal
crossing the Alps, but I'll resist).  Horses were imported from the Middle
East (and Asia?).  (That's why some of them are _Arabian_ horses).

In Europe, humans basically lopped off the entire top of the food chain
and replaced it with their own.  Ditto in the middle east.  Ditto in the
far east, somewhat later.  (Korea came _extremely_ close to eliminating
all native tigers).  Ditto in the Americas after Columbus.

It is only in this century that humans are trying to replace the
top of the food chain with a more natural one (e.g., reintroducing
wolves to Yellowstone), or resisting tampering with the natural
food chain's adjustments (e.g., the spread of coyotes to the eastern U.S.)

>That many species may be disappearing
>every day in the tropics.  Most of these are arthropods that most people
>are too busy to care about.  But from a scientific point of view, at least,
>this is a tragedy of the highest order.

I'm not claiming that the current loss of species isn't bad.  I just
suspect most ecologists would be more upset at a continent-wide destruction
of entire niches (large herbavore, large preditor) than the localized
destruction occuring now.

As an example, _Discover_ magazine made a big deal a few years back
about the efforts to save a type of lark in Central Florida.  There
were _three_ 'species' of lark which could interbreed, filled the same
niche, etc.  One species went 'extinct' shortly after a cross-breeding
effort was started... and it turned out the 'obvious' nearest-kin
species wasn't.

The loss of biodiversity isn't great, but in this case it is hardly
tragic -- there were two other species (if that's the word, since they
could all interbreed) which filled the same niche in the same geographical
area.


Bear Giles
bear@fsl.noaa.gov