Re: An alternative to ST and AAT

Rohinton Collins (
1 Dec 1996 22:47:45 GMT

> But it did not become bipedal to get around faster or more
> efficiently. It is the old, old problem in evolution of
> intermediary stages. Birds did not learn to fly because it
> was a better way to migrate long distances. An intermediate
> stage usually implies some diminution in the normal
> capability and it requires a special explanation. Maybe
> birds started jumping to catch insects. Similarly, the
> origin of bipedalism needs some explanation other than
> getting about more efficiently.
> Paul.

Oh dear, oh dear, oh dear. Intermediary stages? Do you think that the
australopithecines, during their 2 million year existence, said:

"Oh shit, we have to walk with this damned waddling gait because we're just
an intermediary stage, just an evolutionary dead end. Such is our lot in

Think again, Paul. The australopithecines were *obviously* terribly well
adapted or they would not have existed for so long. Evolution does not plan
ahead. Intermediary species - those who are evolving rapidly from one
stable species to another - are very unlikely to be preserved in the fossil
record, since they exist for a relatively very short period of time. Only
evolutionarily stable species are preserved in the fossil record, of which
the australopithecines are a member. During evolution, each evolutionary
stage, must by definition, be better adapted than the last. If you do not
understand this, you do not understand evolution. There was no evolutionary
rubicon during the evolution of bipedalism.

A point of interest. Did anybody see the documentary on the Galapagos
Islands which was narrated by, and starred Richard Dreyfuss? There is a
flightless bird on one of the islands, I forget which species. Having
arrived on the island on the wing several hundred years ago and finding
that the only food source was the sea, the bird began evolving. It is now
caught, like a snapshot of evolution, midway between what it was when it
arrived at the island, and a flightless marine adapted bird, similar to the
penguin. On land, it looks somewhat like its non-evolved cousin species,
only with smaller wings with reduced plumage and a longer neck. When
swimming in the sea it is a wonder to behold. It is still hampered to some
degree by its avian heritage, but it is well on its way to evolving into a
small penguin-like bird. This is the best evidence for evolution which I
have yet witnessed. Does anyone remember the species which I have