Is there any proof of beneficial mutations?

Well, that's not true. Frequently they gain resistance to antibiotics. Once a microbe species was observed to evolve true multicellularity.But, you know, we've only been looking at bacteria for about a hundred years. We've been able to study their genetics for only about 50. It took three billion years for bacteria to evolve into complex multicellular life; the notion that we could possibly see it happen again in only 100 years is an absurdity. How about three billion years, like last time? Um, maybe you could show your work on that? Be specific. Probability is mathematics, you realize that, right? You just can't handwave the math if you want to make an argument from mathematics.

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Boraas (1983) reported the induction of multicellularity in a strain of Chlorella pyrenoidosa (since reclassified as C. vulgaris) by predation. He was growing the unicellular green alga in the first stage of a two stage continuous culture system as for food for a flagellate predator, Ochromonas sp., that was growing in the second stage. Due to the failure of a pump, flagellates washed back into the first stage. Within five days a colonial form of the Chlorella appeared. It rapidly came to dominate the culture. The colony size ranged from 4 cells to 32 cells. Eventually it stabilized at 8 cells. This colonial form has persisted in culture for about a decade. The new form has been keyed out using a number of algal taxonomic keys. They key out now as being in the genus Coelosphaerium, which is in a different family from Chlorella.

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Boraas, M. E. 1983. Predator induced evolution in chemostat culture. EOS. Transactions of the American Geophysical Union. 64:1102.

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Hrm, well, I was either thinking of a different paper (which of course I can't find, now) or I was thinking of a different claim.To some extent the distinctions between single-celled (but consensus-building) organisms, colonial organisms, and multicellular organisms are somewhat arbitrary. But here's a paper that appears to be more on point:

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Cell types are fundamental units of multicellular life but their evolution is obscure. How did the first cell types emerge and become distinct in animal evolution? What were the sets of cell types that existed at important evolutionary nodes that represent eumetazoan or bilaterian ancestors? How did these ancient cell types diversify further during the evolution of organ systems in the descending evolutionary lines? The recent advent of cell type molecular fingerprinting has yielded initial insights into the evolutionary interrelationships of cell types between remote animal phyla and has allowed us to define some first principles of cell type diversification in animal evolution.

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Nature Reviews Genetics 9, 868-882 (November 2008) | doi:10.1038/nrg2416

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The evolution of cell types in animals: emerging principles from molecular studies
Detlev Arendt

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The evolution of cell types in animals: emerging principles from molecular studies | Nature Reviews Genetics

I would guess it depends. How many grandchildren does she have?

That alteration occurs by random mutation and natural selection. Right - the bacteriocidal effect of penicillin produced a selection pressure for resistance, and the mutation that produced resistance came to dominate the Staph aureus population because non-resistant individuals were killed. There's nothing intelligent about it. Bacteria mutate all the time. Constantly. For every bacteria that have mutated to gain resistance to antibiotics in an antibiotic environment, millions mutate to be more susceptible (and are killed), millions mutate to be resistant to a completely different antibiotic that isn't even present (and are killed), millions mutate to become auxotrophs to various metabolites that may not be in the culture media (and are killed), millions mutate in ways that have no phenotypic effect whatsoever (and are killed.)It's literally the result of chance that any bacteria are initially resistant to an antibiotic when it's added. They were resistant before it was added, as a result of mutations that were completely neutral in an environment with no antibiotic.Add the antibiotic, and you're very suddenly looking at a population of bacteria that are resistant to it - because everything else is dead. They don't affect bacteria as a whole; otherwise every bacteria would instantly mutate as soon as the antibiotic was added. But what we see when we add an antibiotic to microbial culture is that 99.8% or so of individuals are immediately killed by it, and only the small fraction that had, by chance, mutated to gain resistance survive.Then they re-establish the population from their descendants, which necessarily contain the mutant gene for resistance. It's not a process where all bacteria sudden;y switch on resistance; it's a process where only resistant bacteria survive, and their rapid growth results in a population generally resistant to the antibiotic.

As a result of mutation. Remember all the bacteria are clones of a single individual. If that original clone had antibiotic resistance than all subsequent individuals would have as well, and therefore none would have died.But most do die. This is proof that the resistance is a trait acquired in generations after the original, and the only possible source of that trait is random mutation. If that's the case, why would any of the colonies die? They all should have been resistant if resistance was a trait present in the founding individual. Remember bacteria are haploid so there's no Mendelian characteristics here - no dominance or recessiveness. Because the founder was not resistant, we know that the resistance (and not the loss of resistance) was the trait acquired by mutation. Oh, I love "I read it somewhere" as a source for claims. Always convincing!

I told you, already. If the trait had been present in the founder individual than all colonies would have survived; any particular mutation is highly unlikely so only a small - not even noticeable - number of bacteria would have lost the trait and been killed by the antibiotic.Replica plating would have produced replicas of all colonies. It only takes a single individual to form a colony, and at least one - though mathematically it's more like almost all the individuals - would not have lost the trait.That's not what was observed. Many colonies did not replicate at all. Any particular mutation is highly unlikely and if a colony doesn't replicate it's because of the millions of bacteria in a discreet colony, not a single one was fit to survive on the test media.The source of almost every trait in a bacteria is vertical gene transfer - direct inheritance from its parent. If a trait is widespread throughout a population it primarily got there by direct inheritance. Because antibiotic resistance was not initially widespread we know that it was the acquired trait, rather than the reverse as you propose. Because the bacteria were clonal and the species is haploid we know the source was mutation. And we know that mutation is random.

A colony is millions, perhaps hundreds of millions of individual bacteria - so many, in such a large pile, that they can be seen by the naked eye.It only takes one viable individual to form a colony. It only takes one. If you replica plate a colony, and no colony forms on the replica plate, then that means not a single one of those millions of individuals was fit to survive on the replica medium.So, no, half of the colonies could not have lost their resistance - that would mean that hundreds of millions of individual bacteria all coincidentally had the same unlikely mutation. Odds that border on absurdity. Just one individual in the colony needs to have the mutation, get transferred as part of the replica process, and thrive on the replica medium to form a replicated colony there. It only takes one. One specific mutation in one individual out of hundreds of millions of individuals, all mutating? Those are very good odds. The odds that you will win the lottery are very small. The odds that someone will win the lottery usually approach certainty (if enough people buy tickets.) Do you need me to walk you through the concept of "replica plating"? It's not difficult, I promise, and it might resolve your confusion, here. Right. It had to exist in the population among isolated individuals or else none of the colonies would replicate. But it could not have been widespread or else all of the colonies would replicate. A bacterium has only one parent, they reproduce by fission (not by sexual intercourse) and the "child" of a bacteria (traditionally called a "daughter") receives the full compliment of its mother's genetics. That's not true of diploid species like humans or pea plants (which obey Mendel's laws) but it is true of bacteria. They have a single parent, all of whose genes they inherit.If a large number of bacteria had possessed the trait and some number of them had lost it, every colony would have replicated. If half of the bacteria had possessed the trait and half had lost it, every colony would have replicated. If .001% of the bacteria had possessed the trait and 99.999% of the bacteria had lost it, every colony would have replicated. It only takes a single viable individual to form a colony.Every colony did not replicate. Only a few (half?) of them did. That proves that antibiotic resistance was such a rare trait amongst the entire plate of bacteria that it could only have arisen by random mutation. As a result of random mutation. The proof of this is that some colonies replicated and some did not, which I've explained. Well, obviously. After all bacteria were transferred to growth media with antibiotic in it, and they survived and thrived there anyway. Obviously they had resistance before they were transferred; if not, they all would have died.The resistance emerged as a result of random mutation. The proof of this is that not every colony replicated - some colonies did not have a single individual out of millions or even hundreds of millions with antibiotic resistance. That's proof that the trait was far too rare to be the result of inheritance; proof that the trait emerged by random mutation.

Yes, for instance the lac operon, which upregulates production of beta-galactosidase for the metabolism of lactose in the presence of lactose and the absence of glucose. If lactose is not present beta-Gal is not produced. If glucose is not absent beta-Gal is not produced. Obviously organisms have an innate, preprogrammed capacity to respond to their environment; in the case of bacteria this usually takes the form of changes in levels of protein expression.But the origin of the lac operon is the same as the origin of all genes - random mutation and natural selection. And if bacteria had the innate genetic ability to resist antibiotics already encoded in their genes all bacteria would be resistant to antibiotics.That's not what we observe at all. When we introduce an antibiotic to a culture of bacteria the first thing that happens is that almost all of them die. Where was their "non-mutational adaptability"? Where was their "innate genetic resistance"?Nowhere to be found, because it was not there. When you add an antibiotic to culture the population crashes, drops to a handful of individuals - the ones who had mutated into a resistant strain - and then the population rebounds as the resistant individuals exploit the sudden lack of competition for medium and grow exponentially.Random mutation is the only explanation for that pattern. If bacteria had a pre-programmed innate resistance to antibiotics the antibiotics wouldn't work. They wouldn't ever work. You could at most expect to kill the 10% or so of bacteria, the ones who had lost their resistance by harmful mutation, and that's essentially pissing in the ocean. I don't think you're entirely grasping the notion of "exponential growth." An antibiotic has to kill almost every single bacterium to be an effective medical treatment. Bacterial colonies are clonal. If they have different "defense mechanisms" then the only explanation for that is random mutation of their defense mechanisms.

Selection is never random, but mutation always is. By fairly simple laws of chemistry it has to be; mutagens are necessarily going to attack DNA at random locations simply due to Brownian motion.

I guess you've never heard the theory of "intelligent falling", then?And actually people do argue gravity, for instance: Conservapedia:Conservapedian relativity - RationalWiki

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The sysops at Conservapedia are concerned about a link between scientific relativity (special and general relativity) and moral relativism, even though the concepts are utterly unrelated and have nothing in common other than the word "relativity".
Based on that comically misguided premise, and perhaps their mistrust of science in general (derived from their opposition to the biological theory of evolution), they attempt to denigrate the science of relativity as part of their anti-moral relativism agenda. As a result, the relativity-related articles at Conservapedia are riddled with incorrect interpretations, distortions of fact, out-of-context quotes from scientists and scientific journals, and elementary errors.
Some of the mistakes may be due to basic misunderstanding of the physics involved, but attempts to correct them have been met with admonishments, reversions and blockings from the administrators, suggesting wilful ignorance in their misrepresentation of relativity.

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Like others have said, the fact that there is a "dispute" here doesn't do anything to buttress the underlying claims of evolution defenders attackers. I mean you can find people who believe the Moon landings are all hoaxes or that 9/11 was an inside job.Among informed experts, however, there's just no dispute about the fundamental accuracy of the theory of evolution and its explanation for the history and diversity of life on Earth. For good reason: there's more evidence for every aspect of evolution than for any other scientific theory, any finding of any court of law, or any medical diagnosis ever made by a doctor. It is 100% true, but it contradicts cherished religious dogma, so people like you have a vested interest in "challenging" it on entirely spurious grounds. If your notions of creationism are true they'll be true because of the evidence that supports them. But that evidence doesn't include the mere fact that you're making the argument. That's circular reasoning.Edited by crashfrog, : Corrected opposite word choice.

Actually the typo is "defenders" instead of "attackers." Oops, editing message for clarity.

Every single living organism is evidence for evolution by natural selection and random mutation.Every single one. That's why the things I said about evolution are true: any medical diagnosis is supported by evidence from only one organism. Any court decision is supported by a handful of evidence from a handful of investigators. Any other theory in science is supported by a handful of scientific experiments.But the evidence for evolution is every single organism that has ever lived. It's no exaggeration. I don't even think you can imagine how many organisms have ever lived, IC, regardless of how smart you seem to think you are.You want to see the mountain? Get off your kiester and head down to the zoo. Head into a library and read some of the piles of papers we've tried to show you, which you ignorantly dismissed. Head into a classroom and try to learn some biology. We can't deliver the mountain to your doorstep because the mountain of evidence is an entire planet populated by living things that you insist on learning absolutely nothing about.Yes there is proof of beneficial mutations. You've been shown it over and over again.

Except that neither you nor anyone else has ever been able to substantiate that, or explain why, if organisms are supposedly designed by the ultimate intelligence, they seem so unintelligent in their design.There's no evidence for "intelligent design" to be demonstrated in the natural world. That's why every thread or conversation you've ever started on the subject has ended with your retreat. Evolution occurs by varying the existing information in the DNA in organisms by mutation. These variations increase or decrease the information content of an organism's genome and produce new function.

It's hardly an insult, it's simply a description of fact.Am I wrong? Is there a thread you've started on this subject that you've not abandoned? And that's fine! I don't expect you to immediately defer to my expertise about anything.But if you're so sure I'm wrong why don't you make an effort to prove it? Why do you spend so much time telling me how stupid I am and so little time defending your arguments with evidence? Evolution is a series of minor variations. Haven't you heard someone say "the journey of a thousand miles starts with a single step"? Isn't a "new function" exactly what you claimed evolution could not, under any circumstances, produce? How would we show you that, since several thousand years would exceed the length of human civilization? We could show you any number of organisms with improved functions over their ancestors, and you'll just dispute that they are the ancestors. Won't you?How about instead of sweeping demands for new evidence to ignore, you stop ignoring all the evidence we've shown you already?