Don't know if you can read this(subscription necessary?) Abstract (or at least the first paragraph):
A fascinating question in biology is how molecular changes in developmental pathways lead to macroevolutionary changes in morphology. Mutations in homeotic (Hox) genes have long been suggested as potential causes of morphological evolution(1,2), and there is abundant evidence that some changes in Hox expression patterns correlate with transitions in animal axial pattern(3) . A major morphological transition in metazoans occurred about 400 million years ago, when six-legged insects diverged from crustacean-like arthropod ancestors with multiple limbs(4-7_. In Drosophila melanogaster and other insects, the Ultrabithorax (Ubx) and abdominal A (AbdA, also abd-A) Hox proteins are expressed largely in the abdominal segments, where they can suppress thoracic leg development during embryogenesis(3) . In a branchiopod crustacean, Ubx/AbdA proteins are expressed in both thorax and abdomen, including the limb primordia, but do not repress limbs(8-11) . Previous studies led us to propose that gain and loss of transcriptional activation and repression functions in Hox proteins was a plausible mechanism to diversify morphology during animal evolution(12) . Here we show that naturally selected alteration of the Ubx protein is linked to the evolutionary transition to hexapod limb pattern.
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Evolution of a transcriptional repression domain in an insect Hox protein
RON GALANT AND SEAN B. CARROLL
Homeotic (Hox) genes code for principal transcriptional regulators of animal body regionalization. The duplication and divergence of Hox genes, changes in their regulation, and changes in the regulation of Hox target genes have all been implicated in the evolution of animal diversity. It is not known whether Hox proteins have also acquired new activities during the evolution of specific lineages. Amino-acid sequences outside the DNA-binding homeodomains of Hox orthologues diverge significantly. These sequence differences may be neutral with respect to protein function, or they could be involved in the functional divergence of Hox proteins and the evolutionary diversification of animals. Here, we identify a transcriptional repression domain in the carboxy-terminal region of the Drosophila Ultrabithorax (Ubx) protein. This domain is highly conserved among Ubx orthologues in other insects, but is absent from Ubx in other arthropods and onychophorans. The evolution of this domain may have facilitated the greater morphological diversification of posterior thoracic and anterior abdominal segments characteristic of modern insects.
One difficulty in debating evolutionists and exposing their claims is that they are masters at the art of equivocation, which means to use misleading language and arguments in order to obfuscate the actual facts of the case. They do this in a variety of ways; from bringing in extraneous data and arguments that lend an air of polish and create the appearance of proof by the very amount of scientific verbiage, while clouding the issue at hand; repetition of the same argument over and over again, even after it has been refuted; bringing up false and tautologous arguments that in essence state nothing but are cleverly contrived to appear as though they are the result of a logical process; cleverly constructed fibs that are cloaked in scientific nomenclature that snare those unaware of their techniques; propagating the myth of Darwin that has been repeated ad nauseam for the past century; and sometimes by straight, old fashioned, bald faced lies and misrepresenting the position of their opposition.
In Thinkplease's rambling FAQ he presents absolutely no evidence of any type of evolution, no evidence of any species change at all, and all of the supposed changes in Drosophila merely produced blind fruitflies, fruitflies with appendages coming out where their eye should be, crippled fruitflies, wingless fruitflies or fruitflies that couldn't fly as well as the original model, sterile fruitflies, dead fruitflies, etc. etc. and producing nothing else except a fruit fly, and not a better, more fit fruitfly that would have survived in the "struggle for existence" in Darwin's strange evolutionary world; again, no evidence of evolution after all the fireworks. It is much so-called scientific clatter about nothing, which shows the desperation of evolutionists to prove their case with so much research producing such meager evidence.