Favorable Mutations? Help me!!

And the answer is, of course, that Malaria has been there for as long as we've been able to tell - so, in short, for west Africa, it is normal, and is thus, *VERY* advantageous. Try harder, Fred!

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Does the nylon example qualify? A quick read of the link and you will see it doesn't. A huge cost is incurred in efficiency, and thus in a normal environment the mutated strain could not last long (AiG also argues plasmid xfer, but the enzyme effeciency loss alone in the article cited by zephyr is sufficient to dismiss mr. nylon as a hero of the evolutionary faith).

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Of course. If nylon production shuts down, that species will go extinct. And yet, species go extinct constantly whenever their niche is destroyed. Subspecies even more often. The point of evolution is that it Expands To Fill Unused Niches. This proves the point - that bacteria expanded to exploit a source of energy that wasn't being exploited yet. Please tell me that you can see the significance of this, when applied to other situations. If we had a hydrothermal vent ur-cell billions of years ago that was confined to its cluster of vents, and it developed the ability to harness energy from light - even if that meant that it wasn't as effective at getting energy from the hydrothermal vents as well - it would be able to spread and fill all of Earth's temperate oceans. You can apply this to almost any situation. Are you so daft that you can't see the importance of being able to utilize a new food source? Especially one that's very different from your traditional food source?------------------
"Illuminant light,
illuminate me."

Well, Fred, you just argued for the presence of God's hand in evolution - you're on your way!!!I find it amazing that you can look at an incredibly simple statement and read God into it. The statement says little more than "if the rate of beneficial mutations rises, the rate of evolution rises". Duh . What, would you read into the sentence "See spot. See spot run!" that it must really be implying "See spot. See spot run because God told him to!"?It no more takes God to raise the rate of beneficial mutations than it takes God to raise the rate that a random number generator produces the number "6". Likewise, it no more takes God to lower the rate of beneficial mutations than it takes God to lower the rate that the random number generator produces the number "6".It is interesting, psychologically, to realize that you equate the words "beneficial" and "non-random". Do you equate them in every context on Earth?------------------
"Illuminant light,
illuminate me."

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Yes, I know, you have a very strong faith. If evolution were true, you should be able to document for me a myriad of examples where a mutated enzyme undergoes additional mutation to increase its efficiency. What do you have to offer?

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Please, Fred, you should be able to do this yourself.Step 1: Go to Google
Step 2: Type into the search bar the words 'mutation' and 'efficiency'
Step 3: Click on the third link - Single mutation at the intersubunit interface confers extra efficiency to Cu,Zn superoxide dismutase - PubMed"The Val28-->Gly single mutant at the subunit interface of Cu,Zn superoxide dismutase from Photobacterium leiognathi displays a k(cat)/K(M) value of 1.7x10(10) M(-1) s(-1), twice that of the native enzyme. Analysis of the three-dimensional structure indicates that the active site Cu,Zn center is not perturbed, slight structural deviations being only localized in proximity of the mutation site. The enzyme-substrate association rate, calculated by Brownian dynamics simulation, is identical for both enzymes, indicating that the higher catalytic efficiency of the Val28-->Gly mutant is not due to a more favorable electrostatic potential distribution. This result demonstrates the occurrence of an intramolecular communication between the mutation site and the catalytic center, about 18 A away and indicates a new strategy to encode extra efficiency within other members of this enzymatic family."How many more do you want?------------------
"Illuminant light,
illuminate me."

Anyway, back to the original poster. I think she wants something more dramatic than changes in bacteria. Lets give her something more interesting - how many things do you want? Let's do two for now.1) The human tail
This is what is known as an "atavism" - a trait retained from earlier species that has become inactivated in our genome. While there are many famous atavisms in nature (legs on whales (most whales just have the joint for the legs)), a wide range of human genitalia atavisms of features only found in other primates, chicken teeth and claws, etc), the human tail is probably one of the most famous. There are two types of tails: pseudotails (which are irregular growths that just happen to be at where a tail would be), and true tails. Pseudo-tails are never inherited; true tails sometimes inherited, depending on whether it was due to environmental or genetic factors (one case has been documented being passed down through three generations). Less than one third of the human tail cases (of which there are over 100) are pseudotails. The true tail is a benign, complex arrangement of fat, connective tissue, and blood vessels, striated muscle, and vater-pacini corpuscles (a type of pressure-sensing organ) covered in normal skin, ranging from 1 to 5 inches long. True tails can be controlled through voluntary muscle contractions. Most cases do not contain bone (although many primates don't have bone in their tail either - such as the Barbary Ape), although there are several cases in which there have been up to 5 additional vertibrae in the tail. The human tail genes have already been mapped in the human genome. All of us, in fact, had a tail as an embryo; however, humans also contain the genes for the apoptosis of the tail by microphages.Of course, a tail isn't advantageous to humans, and up until recent times, people with abnormal development were typically exposed on hillsides, so it's not exactly an advantageous feature, and it's not one that has become widespread, but it nonetheless exists, and is a dramatic example of a mutation reactivating an old feature that has been genetically deactivated.Articles:
Bar-Maor, J. A., Kesner, K. M., and Kaftori, J. K. (1980) "Human tails." J Bone Joint Surg Br. 62-B: 508-510. [PubMed]
Baruchin, A. M., Mahler, D., Hauben, D. J., and Rosenberg, L. (1983) "The human caudal appendage (human tail)." Br J Plast Surg. 36: 120-123. [PubMed]
Dao, A. H., and Netsky, M. G. (1984) "Human tails and pseudotails." Human Pathology 15: 449-453. [PubMed]
Dubrow, T. J., Wackym, P. A., and Lesavoy, M. A. (1988) "Detailing the human tail." Annals of Plastic Surgery 20:340-344. [PubMed]
Fara, M. (1977) "Coccygeal ('tail') projection with cartilage content." Acta Chir. Plast. 19: 50-55. [PubMed]
Harrison, R. G. (1901) "Occurrence of tails in man, with a description of a case reported by Dr. Watson." Johns Hopkins Hosp. Bull. 12:96-101.
Hill, W. C. O. (1974) Primates: Comparative Anatomy and Taxonomy. VII. Cyropithecinae: Cercocebus, Maccaca, Cynopithecus. New York: Halstead Press, John Wiley and Sons.
Hooten, E. A. (1947) Up From the Ape. Second edition. New York: Macmillan.
Ikpeze, O. C., and Onuigbo, W. I. (1999) "A bisegmented human tail in an African baby." Br J Plast Surg. 52: 329-330. [PubMed]
Keith, A. (1921) "Human tails." Nature 106 :845-846.
Ledley, F. D. (1982) "Evolution and the human tail." New Eng. J. Med. 306: 1212-1215. [PubMed]
Lundberg, G. D., and Parsons, R. W. (1962) "A case of human tail." Am. J. Dis. Child 104: 72.
Standfast, A. L. (1992) "The human tail." New York State Journal of Medicine. 92: 116. [PubMed]
Sugumata, A., Sato, M., Ikeda, J., Kinosita, J., Tanihira, S., and Makimo, K. (1988) "Two cases of a true human tail." Jpn J Plast Reconstr Surg 31: 1072.
Touraine, A. (1955) L'hrdit en Mdecine. Masson, Paris.2) *Really Old* fruit fliesA rather interesting experiment was performed by Michael Rose at the University of California, Irvine. He took common fruit flies and left them in a jar to breed at will, and collected all of the eggs - but destroyed all eggs layed by the flies except those layed right near the end of their life cycle. Thus, he induced a selection factor on the flies - long life. Drosophila typically live for about 30 days. After 15 generations, they were living 70-80 days each.Rose, M.R. 1989. Genetics of increased lifespan in Drosophila . Bioessays 11:132-135.Would you like a speciation example (i.e., one species spreads into different niches, and eventually loses the ability to interbreed)? I've got hundreds of them. Hell, I've even got one where an organism split into different *families*. Of course, for the really big steps like that, you're pretty much only going to see it in microscopic organisms, because it takes a lot of reproductions for such drastic change.------------------
"Illuminant light,
illuminate me."

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Who here will say with a straight face that if given the choice, they would choose to have either Hemoglobin C or sickle-cell if forced to live the rest of your lives in West Africa?

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Me. You see, Fred, unlike you, I'm not too into this whole "dying a horrible death" thing. Perhaps you are.And, BTW, most people in West Africa, even in modern times, do not leave West Africa. Did any country, say, in the middle ages, suddenly have a boatload of west africans show up for a day cruise? The reality is, this is where they have lived throughout most of their existence. This is also where malaria has thrived through its existence. For these people, it might as well cover the whole world - because *their* whole world - their niche - is at high risk of death by malaria. Even in modern times with mosquito controls, 300-500 million people become ill with malaria every year (thankfully, we have brought the death rate down to only a few percent, when before if you caught malaria, odds are you were going to die).Just so you know, when you contract malaria, first there's an incubation period. Then you develop the "cold stage". You shake, and often vomit and have a severe headache. Then you develop the hot stage. You begin to get exhausted and anemic. The sweating stage then takes over. Eventually, the brain and kidneys start to suffer failures and become damaged, leading to coma and death.Please tell me that *you* would rather live in a malaria risk zone (before the advent of modern medicine and controls, which haven't been around for even a tiny fraction of evolutionary history) than have a small chance at getting mild anemia or spleen problems. With a straight face.------------------
"Illuminant light,
illuminate me."

Name a type of mutation that you want an example of. Nylon is an example of a mutation allowing an organism to use a previously unexploited foodsource. Apparently you don't think that's worth anything. Fine. What type of mutation would *you* consider beneficial? Increase in efficiency in an enzyme? Anything?Name one thing that you could consider beneficial.------------------
"Illuminant light,
illuminate me."