Tom asks more questions than can be answered in a short email, but a couple
are open to simple, direct answers. One is:

> On the other hand, where is the data that supports evolution?  Why aren't
>  the "intermediate life forms" evolutionists love, anywhere to be found?

This is actually a very legitimate question, and one that greatly excites
every "evolutionist," simply because it strikes at the core of evolutionary
mechanism.

While it is basically true to say that whales are swimming cows and that we
are hairless, bipedally upright apes, what makes these sorts of statements
technically incorrect is that in both instances there was a "last common
ancestor" before the lineages split apart. Neither cows nor whales are like
their last common ancestor. Both branches have continued to evolve over the
years. And in this sort of situation, if you're going to find all of the
intermediate transitional forms that you want, you're going to have to find
them in the fossil record.

And we of course do. There seems to be no gaps in either branch any more. We
seem to have a complete fossil record for both cows and whales, one that is
becoming more complete each year.

However, my favorite example for intermediate forms is that of snakes. If St.
Patrick would have his way with the world and on any given day, eliminate all
of the snakes from the world, and not just Ireland as he claims to have done,
in a single *poof", the most interesting consequence of that poofery is tht
snakes would rearise almost immediately.

In fact, they're doing that now, except again, they're not technically called
snakes. Snakes are lizards without legs. They arose anywhere from 40 to 160
million years ago. The taxonomy of snakes at the moment is quite confused,
and to a biologist, that makes it all the more exciting. Ten years ago, the
issue seemed rather settled. Snakes arose from the mossasaur/varanid family
(Komodo dragons, etc.)  The varanids are the only lizards with the forked
tongues that are characteristic of snakes, and thus that was the basis of the
obvious relationship. But recently, good arguments have also been put forward
that the scleroglossid lizards were the progenitors of snakes, and that the
Boidae (boas, pythons, etc.) are not the most primitive snakes, as had been
believed because many of these snakes still retain their pelvises and femurs,
which still occasionally protrude from the skin, but rather the blindsnakes
are.

Nonetheless, if St. Patrick should have his wish and snakes did disappear,
snakes would never reappear. Snakes have very definite characteristics that
technically make them snakes, and the chances of another line of animals
having these same physiological characteristics is infinitesimally small.

But there is good reason to be a snake, to possess snake-like qualities and
to hunt in a snake-like manner,. Thus snake-like animals would rearise
virtually instantly. Indeed, they're already here, standing (in a manner of
speaking, at least) in the wings, ready to take their rightful place of the
stage of life.

Legless lizards have independently arisen in a multitude of lizard families
all over the world. These families (and that's a technical word) are abound
with "transitional" forms, species with well-formed legs, species with very
short and stubby legs, and species with no legs at all. The lizard families
of greatest interest are the Anguidae (alligator lizards), Scincidae (skinks)
and the Pygopodidae.

A very nice picture of some of the legless Anguidae is at:

    http://www.embl-heidelberg.de/~uetz/families/Anguidae.html

The text on the page is important. From it, you can get a sense of the
transition in progress that this Family represents: "Limbless (Anguinae) or
limbed lizards; all are heavily armored with scales (largely nonoverlapping)
underlain by rectangular osteoderms. Commonly, a longitudinal ventrolateral
fold separates the dorsal and ventral armor on each side, hence the name
"lateral fold lizards". Diploglossines are elongate, limbed lizards, although
their limbs are often greatly reduced. Gerrhonotines are broad-headed,
heavy-bodied and -tailed lizards with short, strong limbs.Ophiodes has lost
the forelimbs but retains tiny hindlimbs."

Similarly, a very nice image of a German legless lizard, species Anguis
fragilis, appears at:

    http://animaldiversity.ummz.umich.edu/media/herp/090.herp.jpg

A completely different group of legless lizards, in the Family Pygopodidae,
which is generally considered a sister taxon to the Gekkonidae (the gekkos),
appears at:

    http://aerg.canberra.edu.au/pub/aerg/herps/fndelma.htm

All of these animals (and more) are the "transitional forms" of lizards
becoming snakes again, and the great joy inherent in studying these animals
is that we don't have to revert to the fossil record to see this transition.
It's occuring now, in our time, with living species.



>  Anytime genetic mutations are found, do scientists shout "evolution in the
>  making"?  No, they scream "ENVIRONMENTAL DESTRUCTION" instead?
>  Why do they hold to evolutionary theory, yet consistently consider
mutation
>  a bad thing?

The answer to that question is relatively simple. If you have code -- and
computer code will do -- that has been optimized over generations and sits a
peak of optimality, virtually anything that you do to it will degrade it,
especially if you do it randomly.

But if on the other hand, your code is a mess, poorly designed, and hardly
working, futzing around with it randomly might actually do about as much good
as harm. In the wake of catastrophes (e.g., the sudden appearance of an
oxygen atmosphere) or in those periods when a novel adaptive zone opens up
(e.g., flight), the few initial species that are found there are generally
never well adapted to the new situation. Thus a few random futzings often
tend to make a great deal of difference and promote very rapid evolutionary
progress. But that all eventually comes to an end, if for no other reason
than the ultimately arrived at designs rapidly become optimal to the current
circumstances [Evolution is a dynamic process that constantly works to cull
error from its designs, where only the best, the most competitive of the
current crop are retained. Indeed, the word "adapt" itselt captures that
dynamism. It means "towards appropriateness" in Latin.] When you've arrived
at the pinnacle of a local optimum, all paths obviously lead downwards, and
any further futzing is simply going to make the end result appear amateurish
and non-competitive.

Wirt Atmar

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