[extropy-chat] Extinctions

[Anders Sandberg]

Damien Sullivan wrote:
> On Sat, Jun 10, 2006 at 03:55:26AM +0200, Anders Sandberg wrote:
>
>> Besides, have anybody calculated how we rate compared to K/T and Perm? I
>> think we still are within the normal noise rate of species/megayear?
>
> More like 100-10,000 times the normal rate.  Possibly comparable to K/T,
> especially if things go on.

A little dive into the data.

I found http://math.ucr.edu/home/baez/extinction/ which has some good
data. The main problem is that we get rates rather than absolute numbers
so far. Doing a bit of counting in one of Baez diagrams produces a lower
bound of around 416 species. http://extinctanimals.petermaas.nl/ gives 921
animal species cand 86 plant species. So if we make the assumption that
this about half the number of real extinctions, we get around 2000 already
extinct species. But this doesn't fit at all with
http://www.soc.duke.edu/~pmorgan/levin&levin.2002.the_real_biodiversity_crisis.html
who claim that about 2000 pacific bird species are gone. Maybe the above
lists were just looking at obvious macrospecies and not the ones
specialists care about. Going to UNEP gives 380+371 (extinct plus possibly
extinct) vascular plants, but I cant get the stupid animal database to
give a complete number.
http://www.unep-wcmc.org/index.html?http://www.unep-wcmc.org/species/animals/animal_redlist.html~main
Making the assumption that the ratio 751/86 for the plants repeats for the
animals, we get a multiplied estimate of the extinctanimals number as 8042
species. So the order of magnitude is about 10,000 species or so, so far.

The total number of species is somewhere between 2-100 million.
http://hypertextbook.com/facts/2003/FelixNisimov.shtml
which gives an extinction so far of 0.5-0.001%. This indeed seems to be
within the noise level.

It is probably indeed shaping up to be the biggest mass extinction since
K/T, but so far it hasn't really got started. The estimates of coming
extinction rates lie between 0.7 (Lomborg) - 50% (various) over the next
century. So if the pssimists are right and nothing happens, we are going
to be on par with K/T (to get to perm we need to work for a few more
centuries).


So, how do we fix it? Looking at it from the big perspective it is fairly
clear that having a big population of a large mammal in all parts of the
ecosystem and mass-flows between previously isolated areas is not
compatible with the past kind of biosphere. So either we go back to being
a smaller species with less room for an interesting civilization,
re-enginer the biosphere to work with us (e.g. increasing the number of
species by engineering new ones and/or designing them to fit with the
technosphere) or go extinct in a good way (preferably by simply going
postbiological or (less likely) leave the planet). Or some combination of
all three. Upload civilizations can be pretty ecological.

It seems to me that most of the traditional proposals of being nice to the
planet suffer the assumption that we can be as we always have, yet in an
unobtrusive way. A bit like wanting cats to be cats, yet not kill small
animals or shed fur.




-- 
Anders Sandberg,
Oxford Uehiro Centre for Practical Ethics
Philosophy Faculty of Oxford University