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Re: BCF ANDPDW



In a message dated 98-08-02 17:27:50 EDT, m_troutman@hotmail.com writes:

<<And quit the "miracles" nonsense.  There are no "miracles" being 
supported here.  Simply exaptations.>>

Obviously I haven't gotten across why the "ground up" BADD paradigm requires a
miracle: The miracle is in the accumulation of a >suite< of characters (not
just one or two but lots) in a non-flying, large, cursorial biped that
suddenly allows it to fly. It is emphatically not the evolution of flight
itself. Did whales evolve flippers >before< they went into the water? No; it
would be a miracle if they did. Then why would anyone think that birds evolved
wings before they went into the air (became arboreal)? Yet this is just what
the "ground up" paradigm maintains.

<<Let me tell you about another "miracle": early tetrapod limbs evolved for
slow "walking" through water (_Acanthostega_); then evolved for walking
(_Ichthyostega_); then evolved for better support on land (temnospondyls,
leposondyls, lissamphibians, early amniotes, etc.); evolved a more erect
stance for 
faster speeds ("theraspids", cynodontids, early mammals); evolved a more erect
stance for even more efficient and faster walking (tribosphenic mammals);
elongated for faster speeds (_Hyracotherium_); and finally lengthened to the
point seen in modern _Equus_.  The same can be explained for the flight
stroke.  Climbing is similiar to the flight stroke kinematically and uses up
similiar energy; gliding is prerequisite to flight energetically,
myologically, etc; and flight is 
similiar to both functions (Rayner 1985, 1991). You can use this sequence in
theropod phylogeny. >>

Indeed; you've encapsulated BCF as well as anyone. As I said earlier, just
good old evolution, proceeding one character at a time, over millions of
years. But--in the "ground up" paradigm, there is no climbing, no gliding, no
nothing before archaeopterygid flight. Big theropods six feet long or bigger
simply ran around flapping their arms, and suddenly, like Peter Pan, they
became small and could fly. This is the miracle.