Ecolog:
Silvert's post opens up all sorts of subjects (cans of worms?), among them
the issue of:
". . . there may even be species that we could do without. Do we really need
anopheles mosquitoes and Plasmodium? According to Wikipedia there are
around
3500 species of mosquito, maybe if some of those which spread malaria were
to go extinct we would all be better off (assuming that we don't consider
them a good means of human population control). We wiped out smallpox, why
not malaria?"
Looking at this issue from a strictly ecological viewpoint (leaving out the
fact that personally, if selfishly, I side with Silvert), the introduction
of DDT to tropical regions drastically altered demographics in those regions
in the 1940's. A lot of misery and death was avoided. I don't have figures
of the effect on population growth, but worldwide, the birth rate continues
to exceed the death rate, with concomitant effects upon the "sustainability"
of resources. I'm personally glad that I didn't die of smallpox, but despite
the development of various birth-control measures, a "sustainable"
population of humans seems to have been exceeded some time ago (say,
sometime between the present and 10,000 BCE?).
So just how do "we" avoid the inevitable crash that results from any
species' eating its seed corn? Beyond that, how do we return to a state of
cheap enough prices for me to continue to afford to eat my foods, not to
mention how much I miss some that are now, for all practical purposes,
extinct? Conversely, how to we keep the price from being bid up to the point
that only Wall Street denizens and Dubai potentates can afford to take
remaining populations below recovery?
WT
----- Original Message -----
From: "William Silvert" <[email protected]>
To: <[email protected]>
Sent: Sunday, November 22, 2009 5:18 AM
Subject: [ECOLOG-L] Insignificant species?
I don't buy this part of Wayne's post, which repeats a widely held view.
Usually we hear the argument that we should not play god and thus all
species are equally worthy of protection. Unfortunately as human
populations
expand and encroach on habitat, and as pollution grows, it is not always
possible to preserve all of the species in the world and we either make
some
decisions or leave matters up to chance. I think that we have to be
realistic and make responsible choices.
Some species are essential and need to be protected at virtually any cost,
and as Wayne correctly observes these may not be charismatic species.
Earthworms and other creepy crawlies are among the most essential
creatures
on earth. These are the species that we have to consider "significant".
Keystone species are almost always both charismatic and significant, but
many others are not, and many prey organisms play an essential role even
though only the specialists have heard of them. Without Calanus
finmarchicus
many of the North Atlantic fisheries would collapse.
But when we have hundreds of closely related species that probably
diverged
only recently, is each one "significant"? There may be a thousand
different
species of nematodes in a benthic grab sample, is each one essential?
And there may even be species that we could do without. Do we really need
anopheles mosquitoes and Plasmodium? According to Wikipedia there are
around
3500 species of mosquito, maybe if some of those which spread malaria were
to go extinct we would all be better off (assuming that we don't consider
them a good means of human populaton control). We wiped out smallpox, why
not malaria?
Of course we have to be aware that not everyone would share the judgement
of
ecologists in these matters. I suspect that most people would welcome the
extinction of the common house fly, whose maggots are among the most
important detritivores on earth. From a political point of view we may
have
to take positions different from what we think of as ecologists.
Bill Silvert
----- Original Message -----
From: "Wayne Tyson" <[email protected]>
To: <[email protected]>
Sent: quinta-feira, 19 de Novembro de 2009 4:32
Subject: [ECOLOG-L] Ecosystems Human intervention Re: [ECOLOG-L] Voyage of
the Beagle: a new podcast on the science of ecology and conservation
I'll ... concentrate on the central point that no species should be
considered insignificant, a lesson that should perhaps be driven home
much
more widely and taken much more seriously. Microorganisms, in particular,
and "non-charismatic" species in general, tend to be left out...
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