Jones quotes and comments:
http://news.bbc.co.uk/hi/english/sci/tech/newsid_1056000/1056040.stm
BBC ... 5 December, 2000 ... Domestic breeds head for extinction ... Many
breeds of domestic animal are threatened with extinction, according to the
United Nations Food and Agriculture Agency (FAO). ... FAO experts say
that 1,000 different breeds of domestic animal have become extinct during
the past century and a third of surviving breeds are endangered. ... The
problem is the success of breeders in the developed world in exporting
animals which have been bred to produce more and better meat or milk.
They go to developing countries where they may lack resistance to
unfamiliar diseases. ... Beata Sherf of the FAO explains: "We can't rely only
on a handful of animals, because animal breeds are adapted to their special
environments and if you transfer them to other environments they don't
produce as well as in the environment they have been adapted to. "You
may just imagine a racing car ... on rough gravel roads. The performance
would not be the same as on the racing circuit. "And the same applies to
animal breeds - if you transfer improved, highly productive breeds from
developed countries into developing countries, with big stresses in terms of
climate, disease and so on, these animals won't produce as in their country
of origin." ... [Another example of the limits of biological change, contrary
to Darwin's belief that there was "no limit to this power... of natural
selection" (see tagline for example of Darwin's use of rhetoric to carry this
crucial points in his theory.)]
Chris
Nope, it indicates no such limits at all. In fact, I'm at a loss as to why
you even think it indicates such a limit. Where is the limit you are claiming?
What it *does* prove is something that you recently *denied*: Natural
selection is *real*, because organisms that evolved in one environment are
not necessarily fit in another and get selected out of existence. These new
breeds are merely *unfit* for such environments, as would be predicted on
the basis of pure Darwinism. In fact, I predict that it will happen again.
Organisms bred in an environment in which disease-resistance is of no
significance will, of course, evolve to have less disease-resistance,
because it is no longer a major selective factor, so any organism with
genes that do not confer disease-resistance will not be selected out of the
population, whereas organisms that don't have the features that are being
bred for *will* be selected out.
The whole piece is actually good *positive* support for a Darwinian view of
consequences of variation and natural selection. Your attempt to twist it
into providing support for the still-unsubstantiated claim that there are
essential "type" or "species" limits on evolution outside of those imposed
by physics and chemistry (we won't find giraffes ten miles tall because
ordinary flesh and bone tissue could not support the weight involved, etc.).
Please let us know when you get some *real* support for this claim, okay?
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