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Author Topic:   Problems with evolution? Submit your questions.
crashfrog
Member (Idle past 1467 days)
Posts: 19762
From: Silver Spring, MD
Joined: 03-20-2003


Message 136 of 752 (575906)
08-21-2010 5:36 PM
Reply to: Message 133 by dennis780
08-21-2010 5:22 PM


Micro evolution works on existing information. Macro evolution works on the introduction of new information. With me now?
No, I still don't follow you. I'm a biochemistry major, so I'm used to thinking of DNA in terms of chemistry, not "information", whatever that is. So help me understand what is being lost in a chemical sense. Does microevolution shorten DNA sequences, and macroevolution lengthen them? I'm pretty sure that's not true at all.
Information NEEDS TO HAVE BEEN ADDED, by any possible process for macro evolution to be true.
I don't know what "information" is supposed to mean, but mutations that add sequence to DNA are well-documented. Over the short term, a few of those mutations may be microevolution. Add up many of those mutations over a longer period of time and macroevolution would seem to be the result. Large-scale change is just the accumulation of small-scale change over longer amounts of time.
In teaspoons? I didn't know I was allowed to invent a measuring system.
You can invent one, or look one up, I don't care; I'm just asking you - what is genetic "information" supposed to be, and how is it measured?
I mean, DNA is a physical molecule. As a biochemist I know how to measure many of its physical properties; molecular weight, number of base pairs, ratio of base pairs to the whole, sequence of base pairs, concentration in aqueous solution (usually in nanograms per microliter), and so on.
I've never measured anything like "information" in DNA, though. Can you tell me how to measure it, or not? If you don't know how to measure it then how can you say whether there's less or more of it?
I am.
Not yet you're not. How do you measure genetic "information"? Be specific. If you can't measure it how do you know what processes result in more or less of it?

This message is a reply to:
 Message 133 by dennis780, posted 08-21-2010 5:22 PM dennis780 has replied

Replies to this message:
 Message 140 by dennis780, posted 08-21-2010 6:58 PM crashfrog has replied

Coyote
Member (Idle past 2106 days)
Posts: 6117
Joined: 01-12-2008


Message 137 of 752 (575910)
08-21-2010 5:52 PM
Reply to: Message 133 by dennis780
08-21-2010 5:22 PM


Macro evolution
Micro evolution works on existing information. Macro evolution works on the introduction of new information. With me now?
No, this is not correct. There is only microevolution.
If you set out to walk to the opposite coast you do it through a series of single steps.
Evolution of, for example, the primates operates through a series of small steps that over time add up to a large step. Looking back on the process we can say that a species change has taken place between points x and y, and can call that macroevolution, but it was really just a series of small microevolutions that added up over time.
Information changes at each small step, sometimes added, sometimes subtracted, but always changed.

Religious belief does not constitute scientific evidence, nor does it convey scientific knowledge.

This message is a reply to:
 Message 133 by dennis780, posted 08-21-2010 5:22 PM dennis780 has replied

Replies to this message:
 Message 141 by dennis780, posted 08-21-2010 7:06 PM Coyote has replied

jar
Member (Idle past 394 days)
Posts: 34026
From: Texas!!
Joined: 04-20-2004


Message 138 of 752 (575918)
08-21-2010 6:34 PM
Reply to: Message 133 by dennis780
08-21-2010 5:22 PM


Micro evolution works on existing information. Macro evolution works on the introduction of new information. With me now?
Huh?
I'm sorry but that is just silly.

Anyone so limited that they can only spell a word one way is severely handicapped!

This message is a reply to:
 Message 133 by dennis780, posted 08-21-2010 5:22 PM dennis780 has replied

Replies to this message:
 Message 142 by dennis780, posted 08-21-2010 7:06 PM jar has replied

Blue Jay
Member (Idle past 2697 days)
Posts: 2843
From: You couldn't pronounce it with your mouthparts
Joined: 02-04-2008


Message 139 of 752 (575919)
08-21-2010 6:35 PM
Reply to: Message 133 by dennis780
08-21-2010 5:22 PM


Macroevolution at work
Hi, Dennis.
dennis780 writes:
Micro evolution works on existing information. Macro evolution works on the introduction of new information. With me now?
Then, behold macroevolution at work:
Hallett and Maxwell 1991
To summarize, here is what Hallet and Maxwell did:
  1. Acquired a colony of bacteria with known genotype for the gyrA gene. This bacterium is known to be susceptible to the antibacterial quinolone
  2. Induced random misrepair mutations in the gyrA gene
  3. Applied quinolone to the colony
  4. Discovered that some of the bacteria were not killed by the quinolone
  5. Sequenced the gyrA gene of some of the bacteria that survived the quinolone
  6. Discovered that one resistant bacterium had a gyrA genotype that was different from the original colony’s genotype (where the original genotype’s 317th nucleotide was an A, the resistant genotype’s 317th nucleotide was a G)
  7. Discovered that the gyrase protein produced by the mutant allele was also different from the original protein of the colony
  8. Isolated the gyrase protein that was produced by the mutant gyrA allele
  9. Tested the function of this mutant protein under varying levels of quinolone
  10. Discovered that the mutant protein could tolerate 10 times more quinolone than the original protein, and still function properly
They showed that random mutation created a new allele (i.e., added information that did not previously exist), that the new allele produced a novel protein, and that the novel protein outperformed the original protein. Thus, the mutant bacteria were selected for by the quinolone regime.
There is no other way to explain this data other than with a beneficial, information-adding, random mutation.
Thus, by your definition, Hallet and Maxwell demonstrated the reality of macroevolution (along with the reality of beneficial mutations).
Are you with me?

-Bluejay (a.k.a. Mantis, Thylacosmilus)
Darwin loves you.

This message is a reply to:
 Message 133 by dennis780, posted 08-21-2010 5:22 PM dennis780 has replied

Replies to this message:
 Message 146 by dennis780, posted 08-21-2010 7:32 PM Blue Jay has replied

dennis780
Member (Idle past 4776 days)
Posts: 288
From: Alberta
Joined: 05-11-2010


Message 140 of 752 (575920)
08-21-2010 6:58 PM
Reply to: Message 136 by crashfrog
08-21-2010 5:36 PM


"So help me understand what is being lost in a chemical sense."
Arrangements of chemicals that contain useful information, genetic traits, etc.
No chemicals are being lost. The arrangement of chemicals that produce useful information is damaged or lost.
"Does microevolution shorten DNA sequences, and macroevolution lengthen them? I'm pretty sure that's not true at all."
Thats somewhat of a generalization, but that would occur if both micro and macro evolution are true. In most cases, incomplete information is used for a new purpose, but does nothing functional initially. Over time, by random chance, the information 'grows', and has purpose.
"I don't know what "information" is supposed to mean, but mutations that add sequence to DNA are well-documented."
The only arguement I have ever heard for any organism adding genetic sequence is Nylonese bacteria, and that subject is still being debated in another thread if I am not mistaken.
"I don't know what "information" is supposed to mean" And you are sure you are a biochem major? You do know what DNA, codons, RNA, etc. are right?
"Large-scale change is just the accumulation of small-scale change over longer amounts of time." So long as new information is being...sorry, as long as new chemical orders of base pairs are being introduced, I have no arguement with this. I just want proof this happens.
"I've never measured anything like "information" in DNA, though. Can you tell me how to measure it, or not?" I already told you in my previous message. In base pairs, chromosomes, and teaspoons.
"You can invent one, or look one up, I don't care" Good. I choose teaspoons.
"If you can't measure it how do you know what processes result in more or less of it?"
"The human genome is the genome of Homo sapiens, which is stored on 23 chromosome pairs. Twenty-two of these are autosomal chromosome pairs, while the remaining pair is sex-determining. The haploid human genome occupies a total of just over 3 billion DNA base pairs. The Human Genome Project (HGP) produced a reference sequence of the euchromatic human genome, which is used worldwide in biomedical sciences.
The haploid human genome contains ca. 23,000 protein-coding genes, far fewer than had been expected before its sequencing.[1][2] In fact, only about 1.5% of the genome codes for proteins, while the rest consists of non-coding RNA genes, regulatory sequences, introns, and (controversially named) "junk" DNA."
Human genome - Wikipedia
"The prokaryotes — bacteria and archaea — typically have a single circular chromosome, but many variations do exist.[3] Most bacteria have a single circular chromosome that can range in size from only 160,000 base pairs in the endosymbiotic bacterium Candidatus Carsonella ruddii,[4] to 12,200,000 base pairs in the soil-dwelling bacterium Sorangium cellulosum.[5] Spirochaetes of the genus Borrelia are a notable exception to this arrangement, with bacteria such as Borrelia burgdorferi, the cause of Lyme disease, containing a single linear chromosome."
Chromosome - Wikipedia
Humans = 3 billion (ish) base pairs and 22 chomosomes (23 if you count determining sex)
Bacteria = 160,000 to 12,200,000 (in the examples used).
Humans have more chemical information than bacteria. I'd try to quit while your behind.
You should consult Dr. Adequate, he's exellent in his responses, and usually beats me. He's on your team too, Team Evo.

This message is a reply to:
 Message 136 by crashfrog, posted 08-21-2010 5:36 PM crashfrog has replied

Replies to this message:
 Message 148 by crashfrog, posted 08-21-2010 7:40 PM dennis780 has not replied

dennis780
Member (Idle past 4776 days)
Posts: 288
From: Alberta
Joined: 05-11-2010


Message 141 of 752 (575921)
08-21-2010 7:06 PM
Reply to: Message 137 by Coyote
08-21-2010 5:52 PM


Re: Macro evolution
"No, this is not correct. There is only microevolution."
See previous post on definition of micro evolution.
"If you set out to walk to the opposite coast you do it through a series of single steps." Only if along the way you get feet to walk with. If you start walking then lose your fingernails, then toenails, then toes, then eyes, then feet, you don't make the journey. You die along the way.
"Evolution of, for example, the primates operates through a series of small steps that over time add up to a large step." If you want to talk about how walking upright, losing fur (increased heat loss), among other things are somehow advantages for apes, then I'm game, but I'm pretty there is no scientific information in your entire response other than:
"Look at them! They look like us!"
"Information changes at each small step, sometimes added, sometimes subtracted, but always changed." Evidence please. Subtracted and changing, yes. Added?? I don't think so.
In fact, apes require upper body strength to defend their troop from outside apes that attempt to mate with the females (since apes are polygamous). They are faster and more agile as quadrupeds, and their fur acts as an excellent insulator from the sun (water loss due to sweat from sunlight). Quadrupeds have better access to food in trees, as well as safety from predators there are well.
Which advantages were your refering to?

This message is a reply to:
 Message 137 by Coyote, posted 08-21-2010 5:52 PM Coyote has replied

Replies to this message:
 Message 143 by Coyote, posted 08-21-2010 7:11 PM dennis780 has not replied

dennis780
Member (Idle past 4776 days)
Posts: 288
From: Alberta
Joined: 05-11-2010


Message 142 of 752 (575922)
08-21-2010 7:06 PM
Reply to: Message 138 by jar
08-21-2010 6:34 PM


"Huh?
I'm sorry but that is just silly."
I'm with you homeslice. evolution is silly.

This message is a reply to:
 Message 138 by jar, posted 08-21-2010 6:34 PM jar has replied

Replies to this message:
 Message 147 by jar, posted 08-21-2010 7:40 PM dennis780 has not replied

Coyote
Member (Idle past 2106 days)
Posts: 6117
Joined: 01-12-2008


Message 143 of 752 (575924)
08-21-2010 7:11 PM
Reply to: Message 141 by dennis780
08-21-2010 7:06 PM


Re: Macro evolution
Your responses are completely off the wall.
I'm no longer going to bother trying to explain things to you. It seems to be a complete waste of my time.

Religious belief does not constitute scientific evidence, nor does it convey scientific knowledge.

This message is a reply to:
 Message 141 by dennis780, posted 08-21-2010 7:06 PM dennis780 has not replied

Dr Adequate
Member (Idle past 284 days)
Posts: 16113
Joined: 07-20-2006


Message 144 of 752 (575925)
08-21-2010 7:20 PM
Reply to: Message 132 by dennis780
08-21-2010 4:56 PM


I never claimed that a mutation added information.
No, I did. 'Cos it's obviously true. If you have a population all with the same allele of a gene, and then a mutation occurs introducing a new allele, you now have more information in the gene pool, because you have two alleles where previously you had one.
"These restrictive breeding practices reduce effective population size and increase overall genetic drift among domestic dogs, resulting in the loss of genetic diversity within breeds and greater divergence among them," writes Ostrander, who participated in a landmark study of the genomic relationship of 85 different dog breeds. "For example, variation among breeds accounts for 27% of total genetic variation, as opposed to 5-10% among human populations"
Is any further comment necessary?
It is manifestly the case that dog breeding has increased the information in the gene pool of Canis lupus, because the information to make wolves still exists, but has been supplemented by the information to make dalmatians and dachsunds and poodles and bulldogs and Old Enlish sheepdogs ... and so forth ...
My point is, and if you read the link a little more (I'll post some below), that of all the documented 400 mutations, none added new information, and none of the species survived. ALL went sterile and died.
But this is not true.
This is a complete 180 to evolution, which suggests that over time, mutations that offer any sort of advantage, increase in numbers.
In the genetic experiments on fruit flies, the numbers of each new strain where entirely at the whim of the experimenters. Also, they were not selecting for mutations which conferred an advantage, but for any mutation which was visible. And they still did not all go sterile and die, you made that up.
X rays have been used to increase the mutation rate in the fruit fly by 15,000 percent. All in all, scientists have been able to "catalyze the fruit fly evolutionary process, such that what has been seen to occur in Drosophila is the equivalent of the many millions of years of normal mutations and evolution.
But this is not what has been seen in Drosophilia. It's not what's been done in Drosophilia.
Your claim of 400 mutations makes it plain. If you take the natural mutation in primates and do the math, you find that since the divergence of humans and chimps (for example) there must have been about 35 million mutations fixed in the two gene pools: which agrees with observation of the genomes.
Rifkin has simply misunderstood the fly experiments. This is not surprising, he's made a career out of misunderstanding things. In the words of Stewart Brand: "Among scientists who have read his work, Rifkin is regarded as America's leading nitwit."
I've come across him before, he used to write for the Guardian. Once in an article he explained that people who produce raw materials must always be poorer than people who produce finished products, because finished products cost more. I wrote him an email, but I don't think he understood it.
I've heard mention of the E-coli evolution miracle. Since all that happened was a group of e-coli lost control of the switch that allows them to metabolize citrate in low or no oxygen environments
But this cannot be true. Breaking a control gene would only take a single point mutation, and in that case all Lenski's populations would have gained the ability to metabolize citrate by now.
it's fair to claim that whether information was gained or lost genetically is irrelevant (even though it was not gained), the one mutation that occurred at 20,000 and 32,000 generations does not give enough time for evolution.
That would be two mutations, that's why they happened at different times.
Over "10 trillion E-coli have been produced over the 22 year old experiment", equalling 1 million years of human life, and ONE genetic mutation has occurred.
But this is not true. That's just all you've heard about. In fact, lots of mutations have occurred in Lenski's experiments, many of which are demonstrably beneficial. The citrate adaptation has received an especial amount of publicity because it is claimed to be experimental evidence of the role of contingency in evolution, making it the "ONE" that you've heard of.
As for human mutation, as I say, we can measure the mutation rate. The average person has about a hundred mutations not acquired from their parents. And this is demonstrably enough to account for our divergence from chimps in the time available --- I can show you the math if you like.
It is a striking, but not much mentioned fact that, though geneticists have been breeding fruit flies for sixty years or more in labs all round the worldflies which produce a new generation every eleven daysthey have never yet seen the emergence of a new species or even a new enzyme.
It is indeed strikingly in line with the predictions of evolution that a lineage will not produce a new species every sixty years.

This message is a reply to:
 Message 132 by dennis780, posted 08-21-2010 4:56 PM dennis780 has replied

Replies to this message:
 Message 151 by dennis780, posted 08-21-2010 8:11 PM Dr Adequate has replied
 Message 156 by Nij, posted 08-22-2010 2:52 AM Dr Adequate has replied

Dr Adequate
Member (Idle past 284 days)
Posts: 16113
Joined: 07-20-2006


Message 145 of 752 (575927)
08-21-2010 7:29 PM
Reply to: Message 133 by dennis780
08-21-2010 5:22 PM


Information NEEDS TO HAVE BEEN ADDED, by any possible process ...
Mutation.
Any questions?
This depends on what you are asking.
Details of the way you'd like to measure the information in DNA.
That is, we want an algorithm where you put in a string of As, Gs, Cs, and Ts and get out a number which is the measure of the amount of information in the string.
I would also suggest that your measure should have the following two common-sense properties:
* The "null string" consisting of no letters at all ( which mathematicians denote by λ ) should have an information content of 0.
* Two absolutely identical strings should have the same information content.
Edited by Dr Adequate, : No reason given.

This message is a reply to:
 Message 133 by dennis780, posted 08-21-2010 5:22 PM dennis780 has not replied

dennis780
Member (Idle past 4776 days)
Posts: 288
From: Alberta
Joined: 05-11-2010


Message 146 of 752 (575928)
08-21-2010 7:32 PM
Reply to: Message 139 by Blue Jay
08-21-2010 6:35 PM


Re: Macroevolution at work
"Then, behold macroevolution at work:"
I love when evolutionists point to antibiotic resistance as evidence of evolutionary change. However, bacteria aquire this information through plasmids, from a process called horizontal gene transfer.
Mutations can potentially account for the origin of antibiotic resistance, but involve mutational processes that are contrary to evolution. These mutations usually eliminate transport genes, and regulatory control systems. While the mutations (in this example) are regarded as beneficial, because they allow the bacterium to survive, some other functions of relative fitness are effected negatively (though sometimes such processes make a recovery afterwards).
This topic is actually talked about in regards to nylonese bacterium in another thread. Although the defence mechanism is available to bacteria, gene transfer usually comes at a cost to some other process, and this process does not demonstrate natural, gradual change over time, but rather a spontaneous response, in which many bacteria have natural reactions to.
Horizontal transfer does not provide a mechanism for the origin of those genes. And evolution is defined as common descent with modification. Horizontal gene transfer does not explain the origin, but provides a mechanism for transferring pre-existing resistance genes.
"Are you with me?" Yeeeeeesssss.

This message is a reply to:
 Message 139 by Blue Jay, posted 08-21-2010 6:35 PM Blue Jay has replied

Replies to this message:
 Message 149 by crashfrog, posted 08-21-2010 7:45 PM dennis780 has replied
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jar
Member (Idle past 394 days)
Posts: 34026
From: Texas!!
Joined: 04-20-2004


Message 147 of 752 (575929)
08-21-2010 7:40 PM
Reply to: Message 142 by dennis780
08-21-2010 7:06 PM


Did you even read the nonsense you posted?
What exactly do you propose as the limiting factor that stops micro evolution from becoming macro evolution?
Is there some reason you are unable to learn how to do quotes?
Edited by jar, : No reason given.

Anyone so limited that they can only spell a word one way is severely handicapped!

This message is a reply to:
 Message 142 by dennis780, posted 08-21-2010 7:06 PM dennis780 has not replied

crashfrog
Member (Idle past 1467 days)
Posts: 19762
From: Silver Spring, MD
Joined: 03-20-2003


Message 148 of 752 (575930)
08-21-2010 7:40 PM
Reply to: Message 140 by dennis780
08-21-2010 6:58 PM


Arrangements of chemicals that contain useful information, genetic traits, etc.
Why would there be a selection pressure against useful "information"? If it's useful, then natural selection will preserve those sequences, not obliterate them. Under natural selection what is lost is useless or harmful phenotypic traits and the genes that encode them.
The arrangement of chemicals that produce useful information is damaged or lost.
No, natural selection will preserve and increase the arrangement of chemicals that produce useful "information" and select against useless or harmful "information."
Thats somewhat of a generalization, but that would occur if both micro and macro evolution are true.
Both macro and micro are true, but that's not what is observed at all. Some microevolutionary processes (like mutation) lengthen DNA sequences. Some species macroevolve by shortening their DNA (like parasites.)
The only arguement I have ever heard for any organism adding genetic sequence is Nylonese bacteria
There's no need to have an "argument" for it, it's fundamental to mutation that additional sequence can be added. Here are the fundamental types of mutation:
Point mutation (exchanges)
Insertion
Deletion
Gene duplication
Gene translocation
Two of those are actually the introduction of something new to the genome; insertion adds one or more bases into a genetic sequence, and duplication introduces an entire copy of an existing sequence (usually adjacent to the original.)
Mutation is how genetic "information" is added to the genome, as well as how it is taken out. That is why microevolution can increase the information in a genome, and why macroevolution is trivially demonstrated as the sum total of many microevolutionary events.
I just want proof this happens.
You want proof that mutations occur? That was identified by Darwin 200 years ago and is a trivial observation. You want proof that mutations can add information? Get yourself a strain of Ames bacteria, expose them to a mutagen, and culture on minimal media. You'll see that insertion must have occurred because you'll see colonies of Ames bacteria growing on a media they shouldn't be able to thrive on.
Proof positive - mutations add genetic sequence. If they didn't, the only evolutionary trend we could observe would be a shortening of the DNA of every single organism across the board. If mutations could never add sequence, only remove it, eventually life would go extinct because no organism would have enough DNA to live. But we don't observe that - therefore, we know that mutations both add and subtract genetic sequence.
I already told you in my previous message. In base pairs, chromosomes, and teaspoons.
Ok, then you agree - mutations which add base pairs to DNA are adding information. Ergo, microevolution adds information; therefore macroevolution must exist as nothing more than the sum of many instances of microevolution.
So, you've just agreed with me that evolution is true. Maybe you want to quit while you're behind?
Good. I choose teaspoons.
Ok. How much information is one teaspoon's-worth?
Humans have more chemical information than bacteria.
Doubtless, because humans have to synthesize more proteins that bacteria do.
But humans have less chemical information, by this measure, than the marbled lungfish, which comes in at an enormous 130 gbp. And the largest genome of all is the single-celled amoeba Ploychaos dubium, at a whopping 670 gbp.
As far as chromosomes go, humans have less chromosomes than guinea pigs (64), garden snails (54), chickens (68), and silkworms (56.) So clearly chromosome count isn't an accurate measure of information content, which every student who has ever double-spaced an essay to make a page requirement is aware of.

This message is a reply to:
 Message 140 by dennis780, posted 08-21-2010 6:58 PM dennis780 has not replied

crashfrog
Member (Idle past 1467 days)
Posts: 19762
From: Silver Spring, MD
Joined: 03-20-2003


Message 149 of 752 (575931)
08-21-2010 7:45 PM
Reply to: Message 146 by dennis780
08-21-2010 7:32 PM


Re: Macroevolution at work
However, bacteria aquire this information through plasmids, from a process called horizontal gene transfer.
Transfer from what? It has to start somewhere. In the case of Hallett and Maxwell 1991, their original population of bacteria were descended clonally from a single individual, so there could not have been any resistance plasmids floating around there for HGT until one bacteria evolved the resistance gene, on its own, by random mutation and natural selection.
These mutations usually eliminate transport genes, and regulatory control systems.
Sometimes they do, but if having such a transport system is maladaptive then isn't it an increase in "information" to remove it?
And what about mutations that add a new transport system, one that transports the antibiotic out of the cell faster than it can diffuse or be transported in? For instance, that's the mechanism that MRSA evolved to efflux flouroquinolone.
Horizontal transfer does not provide a mechanism for the origin of those genes.
No, of course not. The origin of those genes was random mutation and natural selection, which is the origin of all genes.
Edited by crashfrog, : No reason given.

This message is a reply to:
 Message 146 by dennis780, posted 08-21-2010 7:32 PM dennis780 has replied

Replies to this message:
 Message 152 by dennis780, posted 08-21-2010 8:19 PM crashfrog has replied

Dr Adequate
Member (Idle past 284 days)
Posts: 16113
Joined: 07-20-2006


Message 150 of 752 (575936)
08-21-2010 7:58 PM
Reply to: Message 146 by dennis780
08-21-2010 7:32 PM


Re: Macroevolution at work
I love when evolutionists point to antibiotic resistance as evidence of evolutionary change.
It is evolutionary change. Not evidence for it, but the thing itself.
However, bacteria aquire this information through plasmids, from a process called horizontal gene transfer.
Sometimes they do. However, it can be acquired de novo. As can be demonstrated by starting with a clonal line which does not have antibiotic resistance.
Your error shows exactly why you should get your information on biology from biologists instead of creationists. The former have a vested interest in being right; the latter, in being wrong.
Mutations can potentially account for the origin of antibiotic resistance, but involve mutational processes that are contrary to evolution.
That was a strange sentence.
Mutations arise which are beneficial and become fixed in the gene pool by natural selection --- and this is "contrary to evolution"? No, that is evolution.
These mutations usually eliminate transport genes, and regulatory control systems.
But not invariably. For example, some bacteria have evolved to eat vancomycin.
This topic is actually talked about in regards to nylonese bacterium in another thread. Although the defence mechanism ...
Defense mechanism? They eat nylon-6.
While the mutations (in this example) are regarded as beneficial, because they allow the bacterium to survive, some other functions of relative fitness are effected negatively ...
Of course. There's always a trade-off. The properties that make me a good human make me a lousy monkey, and if I tried to leap from treetop to treetop in the rainforest canopy, I'd break my neck.
Horizontal transfer does not provide a mechanism for the origin of those genes.
And mutation does. And we can watch it happening.

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