On Wed, 5 Jul 1995 22:57:28 -0400 you wrote:
SJ>ABSTRACT: Continuing part 3B of my four part response to Glenn's
whale transitional form post, namely: 3. the difficulty of Darwinist
mechanisms of mutation and cumulative natural selection to
account for the immense changes involved in transforming a land-mammal
like a Mesonychid into a whale.
Looking at the Discover sketches of the Mesonchynid - Prozeuglodon
transition, the following obvious changes occurred, and what
selective advanatage they would have had:
1. Mesonychid-Ambulocetus (5 MY)
a. Head: dog-like - crocodile-like
b. Nose - disappeared
c. Eyes: middle of head - top of head.
d. Jaw & teeth: dog-like - crocodile-like.
e. Legs: Mammal-like - reptile-like (front splayed out)
f. Toes: hoofs - webbed
g. Tail: dog-like - reptile-like
2. Ambulocetus-Rodhocetus (4 MY)
a. Body: fur - blubber?
a. Hands: five fingers - four
b. Legs: powerful rear legs - reduced in size
c. Tail: greatly thickened. Flukes
3. Rodhocetus-Prozeuglodon (6 MY)
a. Nostrils: middle of head
b. Legs: disappearing
c. Fully aquatic body
Of course this is only a superficial. No doubt a detailed study of
the skeletons of the above animals would indicate many more changes to
be accomplished to make the required transition. As Denton points
out, in the case of "the large marine aquatic vertebrates such as the
..whales"...only the most general explanations of how such
transitions occurred are offered. Detailed analyses providing
relatively complete blueprints of the transitional stages, including
descriptions of skeletal and muscular morphology as well as
cardiovascular and reproductive physiology and behaviour, to show
clearly that their gradual evolution could have occurred are never
provided." (Denton, p216)
Pitman lists the following changes necessary to convert a land-mammal
to a whale:
(i) "a quadruped would have had a hipbone too small to support the
hind legs and yet too large to permit the musculature necessary to
move the great tail..the whale has a small pelvis...
(ii) The whale's forelimbs are jointless paddles or flippers...
(iii) The whale lacks hair..the body is protected by a thick layer of
fibrous, fatty blubber..Sweat glands are absent.
(iv) The outer skin is criss-crossed with numerous
striations...which..help streamline the flow of water in a pattern
which gives maximum speed for minimum exertion...
(v) Eye, ear and mouth differ from those of land mammals. The eye..is
subtly converted so that light rays through the sea water are brought
to focus on the retina.... It has a sclerotic coat for protection at
great depths..mouth and nose design serves to prevent water
entering...
(vi) The ear is constructed on a different plan from that of the
mammal which receives air-borne sound-waves...the eardrum..is
protected from the high pressure experienced in diving. The orifice
is minute...but whales can communicate over long distances, so that
the ear is not functionally deficient..
(vii) ...whalebone whales have great baleen plates which hang like
curtains from the roof of the mouth..ingenious and perfectly moving
sieves or traps for plankton extraction. The blowholes are placed
backwards, permitting respiration without elevation of the muzzle
above water level...
(viii) ...the breathing apparatus has been refined to ensure a
sufficient supply of oxygenated blood and absorption of carbon
dioxide; also to withstand the great pressures exerted by the water in
deep dives...
(ix) The female whale bears her young tail-first and suckles them
under water. She secretes milk into a specially developed nipple
which fits the baby whale's snout...its windpipe is prolonged above
the gullet to prevent milk ejected from its mother's 'breast' from
entering its lungs..."
(Pitman M., "Adam and Evolution", 1984, Rider & Co., London,
pp212-213)
The issue is not just whether these transitional changes ocurred.
Progressive Creation does not apriorily deny that they did. The issue
here is whether they ocurred by a purely *naturalistic evolutionary
mechanism* of mutations and cumulative natural selection caused these
immense changes.
It is noteworthy that one of the seventeen features which evolutionist
Richard Goldschmidt challenged Neo-Darwinians to provide explanations
for evolution on a gradual step-by-step basis, was "whalebone"
(Goldschmidt R.B., "Evolution as viewed by one geneticist', American
Scientist, 40 (1952), pp. 84-123, in Hitching F., "The Neck of the
Giraffe: Where Darwin Went Wrong", 1982, Ticknor & Fields, NY, p88)
Another of these difficulties is raised by Hitching, namely how did
the whale get its tail?
"One of the principal problems for Darwinians in whale evolution is
constructing a pattern of events for the whale's tail to emerge in
small, naturally selected steps. The point is that the tail moves up
and down, whereas in a land mammal it moves from side to side. This
may sound a relatively small difference, but anatomically it is not.
It means that somehow the whale's ancestor had to get rid of its
pelvis. Now this cannot be done just because the animal would prefer
things this way . However much it wished that it could move its rear
quarters up and down more vigorously so that it could swim faster to
catch more fish, it could improve only up to a certain point; after
this, the pelvic bones would prevent further movement....every
downward movement of such a tail would crush the reproductive opening
of the creature against the back of the pelvis, causing pain and
harm'. Taken to the extreme, there would come a point where the
pelvis would be fractured by the action of the tail, thereby making
survival impossible. Natural selection would work against, not for,
such a change. So for the up-down action in whales to emerge, there
simultaneously had to be random genetic changes that diminished the
pelvis while allowing the tail to grow larger. Apart from the
stupefyingly long odds against such a chain of events happening by
chance...there is a further anatomical objection. At a certain point
in the supposed transitionary period, the hip bone would have been
'too small to support the hind legs and yet too large to permit the
musculature necessary to move the great tail of the whale."
(Hitching, p89).
Johnson observes that "Even the vestigial legs present problems" and
asks "By what Darwinian process did useful hind limbs wither away to
vestigial proportions, and at what stage in the transformation...did
this occur? Did...forelimbs transform themselves by gradual adaptive
stages into whale flippers? We hear nothing of the difficulties
because to Darwinists unsolvable problems are not important."
(Johnson P.E., "Darwin on Trial", Second Edition, 1993, Inter Varsity
Press, Illinois, p86-87)
Continued #4. Evidence
God bless.
Stephen
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