Page 152 - Once Upon a Time There Was Darwinism

from a founder population. What's more, as far as we know,
no new species has formed as a result of humans releasing
small numbers of organisms into alien environments. 102
Actually, this admission is not new. In the century and a
half since Darwin, no speciation such as he proposed has ever

been observed, and no satisfactory explanation has ever been
provided for the origin of species.
Once Upon a Time There Was Darwinism
To explain this, it will be useful to examine what sort of
"speciation" Darwin envisioned.
His theory depended on the observation of variations in
the animal populations. Some of these observations were
made by individuals who bred animals, raising quality

breeds of dogs, cows or pigeons. From among the population,
they selected ones with a desirable characteristic (for exam-
ple, dogs that could run fast, cows that produced good milk
or "smart" pigeons), and bred them. Within a few genera-
tions, their resulting offspring had a high proportion of the
selected qualities. For example, the cows produced much
more milk than ordinary cows.
This kind of "limited variation" made Darwin think that
modification is continual in nature, and when it is extended

over a long enough period of time, it produces a radical
change, that is, evolution.
Darwin's second observation along these lines was that
the various breeds of finches he saw in the Galapagos Islands
had differently-shaped bills than finches on the mainland. In
the islands, long-billed, short-billed, curved-billed and
straight-billed strains of finches developed in the same popu-

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