Beneficial Mutations Made Simple

Hox proteins are thought by some to be the vehicle driving beneficial mutations. For instance, an ongoing experiment on the drosophila (fruit fly) have been conducted for over 80 years. Numerous scientists have bombarded these fruit flies with X-ray radiation, among other techniques, in order to mutate them. Well, it worked. In fact, it worked remarkably well. They were able to produce offspring with eyes missing and wings growing out of their heads. Here is the point: No bionic fruit fly was ever the bi-product of these experiments. (No dragonflies, houseflies, horseflies, butterflies, were ever bioengineered . . Just fruit flies and lots of them). Of those that actually survived essentially produced monstrosities with horrible deformities that certainly would have eliminated them in the wild. Even more damning, the fruit fly is molecularly very simple in relation to that of a human. What is worse, their lifespan is not even a thousandth to that of the average human lifespan. What does this mean? Essentially, it means that the fruit fly has the physical ability to evolve more readily than that of a human being. The fruit fly is relatively simple with a genome, composed of four pairs of chromosomes of about 13,000 genes. Aside from this, they breed at a much quicker rate. So then, surely in 80 to 90 years of experimentation, their generations would be into the hundreds of thousands. Compare that figure to humans. In 80 or 90 years, how many generations have come out of your immediate family? Most likely, in your family, three generations and maybe four generations in that amount of time. If ever there were a prime candidate for macroevolution, the Drosophilia would be it, and yet, nothing even comparable to a new specie has ever evolved. It is unsurprising that their tests are still inconclusive, at best.PBS had a special on such mutations and showed an extra pair of wings on a fly and silently praised it. This of course was their tacit way of proving macroevolution. They neglected to mention that they were a hindrance for flying because no musculature was attached to it. It was as close to a harmful mutation as anything I could think of. The extra set certainly didn't aid in its flight. Polyploidy, gene duplication, or insertions do not adequetly explain any sort of macroevolutionary process. Some biologists believe that appendages like the insect wings and the proboscis of a mosquito must have evolved from a spare leg. For starters, a ”proboscis’ on a mosquito is the needle-like structure that jabs the host to extract blood. (I’m sure many of you are intimately acquainted with the proboscis of a mosquito). They somehow have just guessed that a ”spare leg’ can inexplicably become a functioning proboscis. That is so unfounded that I'm not sure a retort is even worth it.In summary, evolution relies on mutation and hopes that it will be beneficial. It has to rely on this because natural selection and genetic drift both need a gene pool from which to select from or drift within.

Heh. I forgot that I had posted in here. I agree with that statement. You sure about that? Don't take my word for it, as you've assumed that I'm "parroting bullshit."Welcome | Department of Ecology & Evolutionary BiologyJust a moment...Functional evolution of Hox proteins in arthropods - PubMedMutations in homothorax (also known as dorsotonals), which codes for a protein that interacts with Extradenticle, seem to alter the identity of the abdominal chordotonal neurons...The Hox family transcription factors control diversified morphogenesis during development and evolution."http://flybase.bio.indiana.edu/...ve-fly/segment/abdmla4.htm"Mutations that arise in the homeobox (Hox) family of development-regulating genes in animals can also have complex effects. Hox genes direct where legs, wings, antennae and body segments should grow. In fruit flies, for instance, the mutation called Antennapedia causes legs to sprout where antennae should grow. These abnormal limbs are not functional, but their existence demonstrates that genetic mistakes can produce complex structures, which natural selection can then test for possible uses."This quip was taken from the PBS 2 special "Evolution," which was a 7 serie special. The tacit implication is that this is how new body segments can arise due to mutations. If Homeobox genes act as the architect in where what body part goes, then the implication that a chance mutation can cause an evolvement never before seen, and that it can be successful until reproduction.

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The Hox genes are important in body patterning and are thopugh to have an important role in the evolution of differeing body plans but to describe them as 'the vehicle driving beneficial mutations' just suggests you haven't the faintest familiarity with any of the science and are just parroting bullshit from some equally ill informed website.

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The Hox family transcription factors control diversified morphogenesis during development and evolution. They function in concert with Pbc cofactor proteins. Pbc proteins bind the Hox hexapeptide (HX) motif and are thereby thought to confer DNA binding specificity... These data thus endow the HX with unexpected functions; this does not preclude that the HX could, however, play a role in target selection in other developmental contexts... HD proteins during evolution presumably relies not only on changes in DNA binding specificity, but also on changes in transregulatory properties. In this context, modifying the regulation of only a subset of Hox targets while leaving others unchanged, by gain or loss of regulatory modules such as the HX and PFER motifs, might provide evolutionary advantages and be causal in morphological diversification. The importance of a tight control of Hox transregulatory properties in evolution has recently gained further support from the evolving capacity."http://flybase.bio.indiana.edu/...ve-fly/segment/abdmla4.htm"It is presumed that the evolution of morphological diversity in animals and plants is driven by changes in the developmental processes that govern morphology, hence basically by changes in the function and/or expression of a defined set of genes that control these processes. A large body of evidence has suggested that changes in developmental gene regulation are the predominant mechanisms that sustain morphological evolution, being much more important than the evolution of the primary sequences and functions of proteins. Recent reports challenge this idea by highlighting functional evolution of Hox proteins during the evolutionary history of arthropods."Functional evolution of Hox proteins in arthropods - PubMed"The Hox genes have been implicated as central to the evolution of animal body plan diversity. Regulatory changes both in Hox expression domains and in Hox-regulated gene networks have arisen during the evolution of related taxa, but there is little knowledge of whether functional changes in Hox proteins have also contributed to morphological evolution. For example, the evolution of greater numbers of differentiated segments and body parts in insects, compared with the simpler body plans of arthropod ancestors, may have involved an increase in the spectrum of biochemical interactions of individual Hox proteins. Here, we compare the in vivo functions of orthologous Ultrabithorax (Ubx) proteins from the insect Drosophila melanogaster and from an onychophoran, a member of a sister phylum with a more primitive and homonomous body plan."Just a moment...
Welcome | Department of Ecology & Evolutionary BiologyEvery last one of those papers describe, in great detail, Hox being one of the possible pathways for morphology as it relates to an evolutionary process. Furthermore, I don't know what your aversion towards it is. If this isn't what you believe, that's great, because nor is it what I believe. I said that some believe that it is the driving vehicle for evolution. For you to say otherwise, you are either being obtuse intentionally or you're splitting hairs in order to direct attention elsewhere. Your lack of erudition on this matter doesn't negate the dissertations I presented. And diverging between obscurantist and hair splitting isn't doing either of us any favors.

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These abnormal limbs are not functional, but their existence demonstrates that genetic mistakes can produce complex structures, which natural selection can then test for possible uses.

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Yeah, exactly. They aren't functional, which is why I have been stating that the Drosophila has thus far not been able to reproduce 'good mutations,' but rather injurious ones that would certainly eliminate them in the wild due to these deformities. However, my objection is that many evolutionists do think that because these morphologies exist, that a wild phenotype might be able to reproduce new body plans, and hence, aid in the propulsion of macroevolution. And there is nothing wrong with taking that into consideration... so long as they stop presenting it as if it were an unassailable fact, when it is far from it. I'm sorry, I'm not following you. What exactly do you mean? Edited by nemesis_juggernaut, : No reason given.Edited by Admin, : Fix bold/italic codes.

The papers themelves, along with my addition of boldened, highlighted text, is enough to show you what they believe. Its a theoretical outlook on how it may be possible in the evolutionary sense. Even if I didn't have that, all I need is this one sentence. If you fail to grasp what they are saying, then it is truly your lack of erudition or your lack to grasp the English language. Either way, your point is rendered ineffectual and moot."The Hox genes have been implicated as central to the evolution of animal body plan diversity.Hox genes have been 'implicated' as 'CENTRAL' to the 'EVOLUTION of animal body plan diversity... i.e. change, evolvement, from one thing to another. There is no ambiguity. There... is... no... ambiguity as to what this means. If there is still some cloud of confusion looming over your head, then you might want to reconsider some remediation. I don't care if you're the smartest guy in the room, have acquired the most knowledge on evolution, or live and breath evo-devo... It all means nothing when I have proven my point that some geneticists believe that Hox genes might be the driving vehicle in evolution. Once again, I don't see what your problem is. If you don't believe that, then that's fantastic; neither do I. But some do. And that was the entire premise of my post. Why you felt the compulsion to argue against it is beyond me. Why, even after I provided a mound of evidence, you still felt the need to argue is beyond me as well. Are you a polemicist? Does arguing, just for the sake of arguing, fancy some penchant of yours?