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Pittsburgh Professors Challenge Darwin
Syberghost writes "Darwin's Theory of Evolution comes under an interesting attack from an American anthropologist and an Italian biochemist, according to an article from University of Pittsburgh's school newspaper. In a nutshell, Schwartz and Maresca argue that change is not gradual as Darwin stated, but comes rapidly in response to drastic mutations caused by shifting environmental conditions."
Isn't that simply punctuated equilibrium? I'd thought it was already considered part of current evolutionary theory. I'm a neophyte so I'm probably way off; someone correct me. (and no FSM references please; they're already hack and it's under a year old)
You better watch out, there may be dogs about . .
Shifting environmental conditions which are, of course, controlled by the Intelligent Designer, allowing Him... I'm sorry, uh, it to create all these diverse forms of life in just six thousand... oops, did it again, sorry, a few million years. (Seriously, though, did you read some of the comments posted on that page that TFA is on? Yikes!)
This sig, aah-ah, is comin' like a ghost-sig...
The title of TFA reads, "Professor Challenges Evolution", when in fact he is doing nothing of the sort.
From TFA:While Schwartz is challenging a specific premise of evolutionary doctrine, he is by no means refuting the entire theory. Apparently, Nan Ama Sarfo felt the story would be read more if it appeared to jump on the anti-evolution ID bandwagon.
Shame on you, Nan.
____
~ |rip/\/\aster /\/\onkey
I don't want to start a holy war here, but what is it with these Pittsburgh professors repudiating the open source core of Mac OS X? Darwin is a solid UNIX foundation for a great operating system; if these professors can't see that, they must not understand how intelligently designed it is!
... please RTFA. All the guy is saying is that sudden changes are brought about by environmental stress creating recessive genes, and these bring about rapid changes in a population after the recessives start combining in offspring.
The only feature of classic Darwinism that he's refuting is about a single organism's offspring being the only one with the new trait. Interesting notion, but hardly revolutionary.
How much more inflammatory can one get? The article should read "Scientists debate the details of how evolution happens." Talk about being deliberately inflammatory.
As has already been posted, this is a well known theory and as far as I know what the currently accepted evolutionary model suggests.
I think the point he's making is that it's simply not being taught. I know plenty of people (especially on Slashdot) who still believe the old "millions of years of small gradual changes" bit. Natural selection and gradual modification MAKE SENSE to most people and seems fairly persuasive, but it's not really what happened. Honestly I think it's a bit of bait 'n switch... explain evolution one way to a person, then later on "Oh by the way nobody really believes that."
Cwm, fjord-bank glyphs vext quiz
I don't see how this is news.
I suspect these fellows have some interesting new postulate, and the Pitt News just got it wrong.
From the banner at the top of the site, the Pitt News is a student newspaper. Student newspapers quite often do little fluff pieces on professors in various departments.
Obviously when changes happen, they happen rapidly via mutations. However, over time all these mutations "add up" so to speak, so Darwinism as we know it is still very much at work.
:)
I highly doubt that one day we were born from a monkey with exactly the same mutations that are present in us all today - over time things just worked out this way.
Perhaps someone who isn't still drunk from last night can better explain where I'm coming from?
...when Gould came up with it 20 years ago.
Seriously, is the author of TFA a moron or what? Punctuated Equilibria is not the same as "Science is wrong!!!11one"
they're just challenging the claim that it can happen gradually over time in some cases?
Can you imagine how this poor guy must feel? You try to publish some paper (I don't know how important it is), the popular press picks up on it and headlines it with "Professor challenges evolution." I for one know that if this happened to a friend of mine, I would tease them about it for YEARS.
The concept that the idea of rapid change is a revolutionary attack on Darwinism is poppycock.
Darwin's thesis is in two parts - that evolution occurs, and that the mechanism is natural selection. The first part is not under any scientific debate. The second part, the proposal that natural selection is the mechanism has been understood to be not the best mechanism for the process of evolution has been understood for nearly 100 years. Darwin did not understand genes, genetics, nor the mechanisms of genetic drift that occur within populations. This knowedge postdates Darwin's original work.
The understanding of evolutionary mechanism works at the level of genes, and populations whereas Darwinism was concerned mainly with species.
This view of the mechanism of evolution is widely misunderstood in the creationistic and anti-evolution communities, and ignorant articles often appear trying to discredit evolution based on a fundamental misappropriation of the topic.
It's a shame that this sort of article was published on Slashdot - it shows a great ignorance of the topic.
Yes, it's just punctuated equilibrium, and it's been discussed quite a lot for many years and really doesn't contradict Darwinism at all. No one is suggesting that evolution happens via "saltation" - when genomes makea radical shifts in one generation. Large random changes in a genome are just about guaranteed to be nonviable. The only thing that is even apparently controversial (it really isn't) is whether the rate of change is hihgly variable or not.
Dawrwinism proposes that such powerful evolutionary forces as predator/prey arms races and sexual selection will be episodic - they move along quickly until something close to a state of stability is reached - the rabbit is a little faster than the fox, but not so miuch that the fox can't survive.
Helium balloons want to be free.
As with so many arguments in society and science, people almost always need to choose one side or the other. In the evolutionary theory debates, the battle between the gradual change camp and the punctuated equilibrium camp has been going on for a long long time. As an antro major, we discussed both ideas in class, but really never talked about "what if it's both". The idea that change is always gradual has its merits in that biology is always trying little experiments in adaptation (e.g. mutations). Most don't work, but some get to hang around and eventually get expressed rather regularly in a population. Then, under a specific stressor, those organisms with that trait suddenly have an advantage over their brethren. The ones without this nifty trait die off leaving the ones with the trait. This gets seen as a sudden adaptation in the fossil record, even though the development of the trait was gradual. In general, biology doesn't work fast enough to respond to rapid environmental stressors. Biology of different organisms work along the same time lines as the organism's reproductive cycles. Bacteria can change more quickly than apes because bacteria reproduce much more quickly, but relative to the organisms themselves, the changes are slow.
Swisssushi - When the going gets tough, get some tenderizer
This theory states that on radical environment conditions, some naturally-produced "mutation inhibitors" are reduced, creating mutations in large populations. These mutations are invisible, i.e. in the form of recessive genes, until two individuals with the same gene have an offspring.
Of course, nothing guarantees that the offspring won't be a horrible mutant and die because of an "unknown disease".
What's funny is that this article is a great example of how evolution isn't a dogma. The scientific community is constantly seeking to improve or amend it. Insteal the ID'ers (funny how close that is to "idolaters") will just use the headline "Scientists disprove Evolution."
The actual article is available from The Anatomical Record Part B: The New Anatomist" volume 289B, Issue 1 , Pages 38 - 46. The abstract's free, although the article itself may require a subscription or university account. The flareup seems to be with this sentence in the abstract (I haven't read more yet): "In evolutionary terms, extreme spikes in environmental stress make possible the emergence of new genetic and consequent developmental and epigenetic networks, and thus also the emergence of potentially new morphological traits, without invoking geographic or other isolating mechanisms." In other words, a change in the environment puts organisms under extreme stress, overloading the ability of various DNA repair mechanisms to counteract DNA damage and mutation, occasionally resulting in novel, beneficial mutations. Several other posters have already said this really isn't anything new, for instance it's known that some bacteria actively mutate their DNA in response to extreme environmental stress. The author (Schwartz) may be hyping his claims some, but really it looks like a case of the reporter going gonzo, and might be a creationist yahoo to boot.
I mean, what else are you going to develop for? OpenSolaris? I think NOT!
There exists no way of exchanging information without making judgments. --Bene Gesserit Axiom
And topical, too. I hadn't considered the nature of evolution for upwards of a week, and it is important to keep these things in the forefront of public consciousness. Even here in the UK, without constant scrutiny of the urgent details of the comparatively recent Darwinian theory of Evolution, buses wouldn't run, power plants would fall quiet and unprovoked creationists would pray peacefully.
Their not repudiating Evolution! They're simply saying that it runs faster on "Schwartz and Maresca" than it does on Darwin. Although the article doesn't say it, I'm pretty sure "Schartz and Maresca" is a Linux distro, a.k.a. "S&M Linux".
Old people fall. Young people spring. Rich people summer and winter.
you know, the first time i even heard of intelligent design was on slashdot. the only time i ever see a post about intelligent design is from people like you who know doubt ran off to teach yourself every little thing about intelligent design as soon as you heard about it. everytime there's a long pointless thread about science vs. intelligent design it's always started by people like you. just shut the fuck up. go make these kinds of posts on intelligent design message boards or something. WE ALREADY GET IT. and for the 10 people on slashdot that do believe in intelligent design, so what? they never say anything about it and if they ever did just mod them down and ignore them. you know why this shit hasn't died down? because of idiots like you that keep bringing it up. either go kill some intelligent design proponents or shut the fuck up and ignore them like a normal person; stop obsessing over them. "oh but if we ignore them they'll gain strength and everyone will be forced to learn ID!" yeh right. you know that isn't true and if it somehow ever did happen you would be completely justified in starting a bloody revolution. so even if you don't want to ignore them, ignore them in the hopes of being able to wage a war on them later. geez
if i'm not immortal, what's the point of living?
...te?
Perhaps someone who isn't still drunk from last night can better explain where I'm coming from? :)
See, it's your brand of wannabe cool that is so endearing about this site. You should have inserted an extraneous reference to your girlfriend, too - that would have ensured the love and admiration of your fellow palm fuckers.
Slashdot - where whining about luck is the new way to make the world you want.
so basicily what he is saying is if we step up our polution efforts and generate even more global warming me migth stand a chance to all become x-men.... hmmmmm hard choice..... koral reefs OR be a x-men >=)
Wasn't this whole debate put to rest in the luria and Delbruck experiments where they showed random mutation leads to resistance not acquired immunity? Basically showing that the enviromental condition doesn't lead to the evolution it's all random.
...be "gradual" or "sudden" is a function of the granularity you work at. If you take a broad overview of evolutionary history then it looks very gradual. An expert in bivalves might consider the lengthening of a shell by 2mm in a time too small to discern from the fossil record as something sudden whereas most people, in particular those studying evolution for the first time, would be entirely justified in considering the change to be gradual. So please, if you're going to argue about this, define your terms.
"The White House is not an intelligence-gathering agency," -- Scott McClellan, Whitehouse spokesman.
The professor hasn't challenged evolution by natural selection, but rather gradualism, as did Steven J. Gould. Darwin did posit gradualism, so an accurate headline would have been to say that the professor had challenged Darwin. As it is, it appears that it is the theory of evolution, rather than the detail of Charles Darwin's theories that is being challenged.
The article is to be commended upon the elucidation of the "dual mutation theory"; is it a shame that it did not make clearer that this theory restores natural selection to the driving seat.
This is important, since responsible editing that promotes truth over political advantage should seek avoid false inferences from being drawn by the less sophisticated.
Faithfully,
Wikileaks, no DNS
When I was there I only read it for the Police blogs. They were the best part.
I can't really see it matching the Washington Post or New York Times any time soon.
Sean D.
"Hmm. I am to metaphor cheese as metaphor cheese is to transitive verb crackers!"
Please, stop with the sensationalism.
All this means is that the size of a step in a particular direction an animal can take can be large to accomodate a large environmental impulse. But most environmental changes are gradual and therefore most responses are as well. Otherwise there would be big oscillations, e.g., an ostrich has a parakeet which has a penguin, etc.
Control system 101. The guy just thinks the steps can be greater than we imagine. Makes sense since we don't get many opporunities to experience significant changes.
You are checking your backups, aren't you?
It is common knowledge that Darwins theory does not specifically goes into details, but gives a general framework to think evolution of organisms in. Though it is not proved, people in the community have a sense that some mutations are not gradual, and evolution does not solve some problems twice. Genetic code contains a lot of junk, but people do feel that junk has a purpose like memory about past problems. Coming to the funny part, as this guy states about evolution, fish did not ever try to grow one tooth at a time. It probably occured by hardening the jaw first, having some divisions in the jaw, having harder parts on top of the jaw(Called the tooth) and having many tooth. I seriously doubt wether this guy knows Darwins evolution at all..
You will never have experience until after you needed it.
Neat to see my school's newspaper on Slashdot!
Not so neat to see it featured because of a misleading and poorly written article by someone who clearly doesn't know what this is about. He's not attacking evolution, he's just present an alternative to one aspect of it. The article makes it sound like this is a completely different theory. Way too sensationalist.
Not unless the stressor is a mutagen, certain chemical insults or radiation for example.
Environmental stress leads to changes in selective pressure (not in mutation), and often to changes in the traits subject to significant directional selective pressure. This acts on the ongoing background (and relatively constant) mutation rate, to drive divergence from the existing means and toward some new equilibrium, and you get rapid evolutionary divergence from the parent population.
Also, there is nothing in existing evolutionary theory that restricts speciation in a small or stressed population to a single common ancestor. Mutation can act within any member of the population and spread through the population from multiple individuals, and selection drives changes in gene frequency in the entire population; almost by definition, speciation is a population event, not an individual event.
and they'll surely welcome the greeting from an illiterate anti-religious nut.
Best comment ever.
But (as I'm sure you'll admit) evolution isn't the same thing as speciation; you could, for example, have two different species (say, hares and foxes) engaged in an ongoing arms race, evolving quite rapidly, yet neither population splitting into two or more sub-species. Conversely, you could, at least in principle, have two populations of the same species that were separated in some way gradually "drift" into separate species. So the evolution of adaptive traits is not the same thing as speciation, and, as I said before, it is natural selection, not genetic drift, which drives evolution.
But even the case for genetic drift "causing" speciation is not as strong as you seem to think; for it to work the two populations would have to occupy very similar environments (to prevent differential natural selection from swamping out the effects of drift--remember, random walks scale with sqrt(t), while a typical bias tends to be liniar or better). When you consider that the "environment" consists of all the other species in the two environments, as well as the physical environment, and whatever is keeping them apart, and so forth...even the article you linked to doesn't make a very strong case (mostly argument from authority) for what is a rather implausible theory.
-- MarkusQ
When Darwin wrote it, heritability was clearly accepted as a fact, but nobody was close to thinking about the mechanisms in any more detail than an almost prurient interest in the diversity of mechanisms for reproduction.
Over and over Darwin emphasises that variation necessarily precedes selection without pretending to have any detailed idea as to how such variation occurs. IMNSHO, the subsequent and continuing lack of interest in the mechanism(s) of variation is a big reason so many otherwise often reasonable people have trouble getting their heads around evolutionary theory. And it's not as though there hasn't been a lot of progress on that front, especially our increasing understanding of genetic recombination and regulation.
All Darwin basically said about natural selection was based on the idea of a struggle for life, something familiar to nature and those living closest to it, but something most humans want to deny themselves and theirs any experience of. He realised that natural selection provided a much slower acting analogue of the artificial selection long practiced by breeders of varieties of domesticated animals and plants, where the breeders' fancies replaced the struggle for life as the detemining factor.
What was most surprising was how few mistakes of detail Darwin actually made, having been born into a culture that just assumed separate creation and having to see past that himself before he could organise his thoughts.
He was able to develop an appreciation of deep time based on little more than the obvious age of geological strata and without well understood evidence of anything more traumatic than the end of the most recent glacial advance. Plate tectonics and receding galaxies needed to wait for another century.
Without the powerful notion of fractal self-similarity to explain the shape of the tree of life, he felt he had to go through the argument at several levels as to how a few descendants of a successful line would diversify over time, most recently to form separate species, then families*, etc. all the way back up the Linnean heirarchy.It isn't the mechanism that works at the level of genes but a very narrow mathematical approach to allele frequency and similar. That power of that math still doesn't let you escape the fact that it is whole organisms through at least some kind of relationship with others of their species who either successfully breed or die virgins. Viability in nature's struggle for life is determined at every point of an organism's life cycle.
*the prior use of terms like 'families' suggested an unstated wider awareness that some kind of relatedness might exist between species.
-- Our systemic servants do not good masters make.
I guess if I was born in a jungle instead of a hospital I would've come out an ape?
Stephen J. Gould whoops with triumph in his grave.
nt
GENERATION 26: The first time you see this, copy it into your sig on any forum and add 1 to the generation.
SUNDAY! SUNDAY! SUNDAY!
Be at the Pennsylvania state fairgrounds!
As the Deadly duo
The Pittsburgh Professors
challenge the
Father of Modern Biology
Charles Darwin
to a handicap grudge match in the steel cage.
It promises to be a match the world will never forget as high flying theories and hard core evidence are used to bash each others skulls in.
The Violence! The Pain! The pure Savagery! This match is not for the faint of heart, only come if you want pure action.
Ticket are on sale RIGHT NOW! So go get some, and we'll see you sunday!
Of all tyrannies, a tyranny sincerely exercised for the (supposed) good of its victims may be the most oppressive
Wikileaks, no DNS
This article, in a word, is bunk. The claims this guy is making are goofy and demonstrably misinformed about what evolutionary theory is.
Some basic background:
Punk eek was opposed to phyletic uniformatism/gradualism (which many consider to have been a cheap straw man anyway). This was a debate over macroevolutionary history: the patterns of large scale morphological and species change. Contrary to popular opinion, macroevolutionary change is subject to all sorts of different forces: things like large scale, genetic drift, extinction events, and so on. No biologist claims that natural selection is the only factor in the particular history of life on earth.
This guy is is not talking about things on the scale of punk eek. He's talking about things on the scale of microevolution, and what he's proposing seems to be a form of saltationism. At best, he's attacking a purported gradualism in actual mutation rates (which itself is nonsense: it's mainstream genetics that different species have all sorts of different mutation rates as well as different rates of morphological change). But for all the rhetoric, nothing he says that's actually correct is even slightly revolutionary. At best, he's proposing another mechanism for variation: variation that involves "good tricks" in a certain genomic sequence that environmental stressors can make happen in many different individuals at once. But variation of ANY sort still just provides the raw material for natural selection to work on. And without natural selection at work, mutation would still be just ultimately random garbage. It's only by placing mutations through the sieve of actually being expressed in individuals that any information about the environment can be imprinted onto a given gene pool. That's the only way we know of that random jostling can be transformed into functional movement. For the mutations to somehow "predict" or "will themselves" to happen in certain linked ways that have a non-random purpose requires some other mechanism, and this guy proposes nothing.
And that's me being the most charitable. Most of the rest of what the guy says is just total nonsense. For instance, he implies that cellular repair systems resist mutation (heck, he even speaks about whether they "willingly" resist change or not!). Well... yes. But they fail. All the time. Most everyone reading this has recent and unique several mutations, right now. And that's not even to mention that you'd have to be grossly misinformed about Darwin to think that "Darwins theory" says ANYTHING about genetic mutation. Darwin hadn't a clue what genes or DNA or the rest of it even were! All he spoke about was the differential success of different variations. Of course, what Darwin thought is irrelevant trivia to what is true in biology, but still, this guy is just showing both his ignorance and his obsession with the idea that Darwin is some sort of "high priest" whom he is fighting against.
Now consider this: "according to Schwartz, mutations occur recessively and are passed unknowingly until the mutation saturates the population. Then, when members of the population receive two copies of the mutation, the trait appears suddenly."
Either the reporter got this wrong, or this guy is really misinformed. Mutations can be recessive or dominant. Nothing about them makes them occur "recessively" only. While the scenario he describes can and does happen (recessive traits that don't really start appearing in force in a population until they become near fixed), nothing about it is particularly revolutionary. And something with complex functionality and specification like fully formed "teeth" is not going to evolve completely out of sight, unexpressed, and then burst onto the scene all at once. That, kids, is called saltation, and while big saltationist jumps can certainly happen (and can spring out via the recessive/dominant pathway), they are very very very unlikely to ever hit upon something functional and useful. Remember: only the actual testing
I think that none should trash any theory, unless there are some clear evidences and, much better, when there is one theory able to provide answers when the other ones cannot.
Evolution theory seems to be quite reasonable because it seems to rely on very few postulates when compared to other theories.
If other theories need fewer postulates and provide more answers, then chances there are that they will succeed.
I'd suggest a quick read of "The Fabric of reality" by David Deutsch for deeper details about this philosophy.
In any case theories about evolution are themselves subject to evolution whenever the objective is to provide answers.
Maybe Computers will never be as intelligent as Humans.
For sure they won't ever become so stupid. [VR-1988]
Darwin based his theory on morphological observations long before the genetic mechanisms were first postulated. Darwin couldn't even have defined "rate of change" within the modern view. I was reading about rare blood types just the other day.
http://en.wikipedia.org/wiki/Blood_type
The human species contains a lot of genetic diversity hidden away in small subpopulations. The origin of these unusual genes is most likely a slow process. However, changes in the configuration space of a population can take place extremely rapidly (tens of generations). For example, within the human species, red hair is more common among the Irish than it is among the Japanese. If it turned out that red hair confered immunity to next great plague, the configuration space of the human species could change extremely rapidly.
Imagine you have two human populations, one with the trait "narrow hips" and the other with the trait "wide hips". The mutation "big head" might confer some survival advantage if the infant/mother survive child-birth, but each time the mutation takes place within the "narrow hip" population it soon disappears again. Natural variation can supply the same mutation over and over again but it can't take hold until it occurs against the background of a viable configuration space.
What's most apparent in the fossil record is not the introduction of new traits, but the collapse in the diversity of alternatives. If a global pandemic wiped out the entire human population except for a small group of Duffy-negative individuals in Africa, it would seem like the "evolution" of human blood type had taken a surprising jump. Quite the contrary, it wouldn't even be anything new, but just a lot more of what you already had in the population (largely unnoticed) at the expense of a lot of diversity that used to exist.
We've had about fifty years of experience now whether evolution runs fast or slow with since the introduction of synthetic anti-biotics.
http://en.wikipedia.org/wiki/Antibiotic_resistance
Resistance to individual antibiotics comes first, emergence of the superbug comes later. The superbug is just a configuration of genes that emerged elsewhere. Which portions of this process were the fast or slow parts, or does it just depend on what you are looking at (the emergence of novel genes, or the blood infection mortality spike thirty years later)?
On the longer time scale, we see mass extinction events every 50 to 100 million years or so.
http://en.wikipedia.org/wiki/Extinction_events
It could be construed as periods of relative stability punctuated by great change. Or in the cartoon mentality that pervades these debates: fifty million years of not much happening, then blam an asteroid strikes and evolution kicks itself into high gear. Here's the question. Take a species that survives the extinction event (after 50 million years of relative stability) and ask yourself this: if the asteroid had struck twenty million years sooner, would that species have survived? Or did something not terribly obvious change within that species during that time period that permitted it to survive when it might not have otherwise? Or conversely, did "quiet" changes take place in other species who would have survived if the asteroid event had come sooner, but didn't in the e
Changes in the environment cause 'evolution'. If the changes are gradual, species will have longer to adapt. If the changes are sudden, then affected species have to adapt rapidly or become extinct.
Reality has a notoriously liberal bias -- Stephen Colbert
There's some crazy, crazy, irrational people out there. I'm not sure they aren't growing innumbers as well.
Welcome to the new dark ages....
Changes in the statistics of the presence of genes in a population over time is evolution.
No, this is a meme of the anti-evolution crowd (part of the "scientists dispute evolution" nonsense) that is to often repeated by loose-thinking scientists and popularizations. You are confusing one of the intermediate effects of evolution (an effect which, as you note, could have multiple causes apart from evolution) with evolution itself. Lets see how that sort of fuzzy thinking looks like in another environment:
To which, of course, you reply: No, no, no! The heliocentric theory of the solar system explains why we see the sort of pattern of sunlight that we do--it isn't just the change in sunlight, but a specific theory that predicts why we see the sort of patterns of change of sunlight that we do.
Same deal in evolution. Or to bring it on home: giraffes, bats and whales all had a reasonably recent common ancestor. There is no reason what so ever for genetic drift to have taken this common ancestor towards any of the three forms in particular. The amazing fact is, we do not find whales grazing the savanna, bats swimming in the open sea, and giraffes hanging upside down in caves. The odds against the situation we do see are already pretty steep, and when you throw in polar bears, monkeys, elephants, house cats, foxes, and so on it gets down right amazing that every population seems to have "drifted" from the common ancestor in a way that suited its environment.
Now, the genetic drift idea just leaves this hanging out there, and doesn't even attempt to offer an explanation (which is why the closet Intelligent Design people keep trying to keep it in play). But Darwin makes a bold prediction; this directed change is not the result of any magical force, but rather the effect of a simple, natural process; the change was random, but the maladapted variants died off at a faster rate than the rest. In the ocean, bat-like mutations just didn't do as well as the whale-like mutations.
There are many studies of such populations in absence of at least known natural selection factors that show evolution (changes in gene distribution statistics).
Same problem: evolution isn't just change, it's adaptive change.
While genetic drift is a stochastic process, an allele is truth state, and eventually it will propagate throughout the population, or disappear completely.
Granted. But it's a string of nonsequitors.
The power of genetic drift effects can be seen in a striking example in the human race - every living human has mitochondrial DNA originating from a single female. There are many other examples of human populations (where natural selection is generally not a factor) that for one reason or another are genetically isolated and are quite divergent in their genetic statistics.
This is another Intelligent Design meme: that some how, humans are magically out of reach of natural selection now. It is completely unfounded--unless you are claiming that something like "everyone has exactly the same number of children" or "people's inherited characteristics have no effect on their breeding success", you'll see it as soon as you stop to think about it.
But in any case, even if it wasn't begging the question, why should we be the least bit surprised about the mitochondrail DNA?
The evidence is pretty clear that genetic drift is an important cause of evolution. Some feel it is more important than natural selection.
The evidence is smoke and mirrors and the people who have been taken in by it either 1) have an agenda or 2) aren't thinking very clearly. You can trot out all the "experts" that you want, but if an idea doesn't hold water (or, as in this case, needs a supernatural entity to care the w
Creationism and ID states that the universe is only several thousand years old. Our observations of the universe clearly show objects millions and billions of years old. That's all that is needed to refute ID.
...previewed the theory?
(grin/duck/run)
Got time? Spend some of it coding or testing
it's essentially without the "equilibrium" part. (-:
SJG advocated "survival of the luckiest" rather than "survival of the fittest", which is another distinction between punk-eek and this.
But yes, it is different to moribund gradualism. Now all they need is an actual mechanism, and they're away. Cue much hooting and jeering from the Progressive Creation crowd.
Got time? Spend some of it coding or testing
The results of a change in genetic coding are not bound to reflect the size of the change itself.
The fact that you've bolded "beneficial" seems to imply that you understand this already, but I see no particular reason to arbitrarily decide that a more sweeping effect is going to be more survivable than a small one. Intuition tells us that a small experimental change is easier to manage than a larger one, but Real Life(tm) may not agree with our intuition.
As a thought experiment, consider a hypothetical species of gliding squirrel which is, overnight, trapped on an island as a large wave comes through and erodes the land-bridge connecting the colony to most of their food sources. I chose a gliding quirrel for their noted swimming abilities (ie, they don't have any). If a large mutation tripled the gliding range of one of the squirrels and allowed it to glide ashore to food, and back to mate, the massive advantage this confers might more than compensate for other massive damage (albinism, susceptibility to cancer, ugliness, reduced ability to grip trees, whatever) caused by a "reckless" mutation.
Sound plausible? That's the beauty of thought experiments: it's very difficult for anybody to prove you wrong. (-:
I suspect that this theory is, at heart, being mooted as an answer to the concept of Irreducible Complexity. It isn't, but it does look like a step in the right direction.
I wonder if it would be worthwhile tossing together a thesis on the developmental progress of all of these attempts to replace an obviously broken set of theories with one that bears at least a passing resemblance to reality? I could call it something like "the evolution of evolution" and flog the film rights for a small fortune. Genius (sometimes demented) plays the role of mutation, and peer pressure (often wrong) plays the role of natural selection. It's bound to be a winning formula!
Got time? Spend some of it coding or testing
At first I was astounded by your response; then, I realized, that you had systematically missed the point, by substituting the concept of variation (differences amongst individuals) for the concept of diversity (the range of different types of creatures in existence) that I explicitly used. Thus, you are (consistently, at least) talkinmg about why Spot has large brown spots and Rover has small black spots and ignoring the larger issue of why dogs exist in the first place.
So going back over it again, but keeping these two concepts straight:
As an aside, your argument that "it MUST work that way because an organism cannot predict what kind of variation will turn out to be adaptive in advance" is flawed. Evolution is no guarantee that organisms will be adaptive in the future; it only appears that way when (as is often the case) the future turns out to be fairly similar to the past. And, in any case, you are confusing levels; even if organisms could predict what would be adaptive in the future, they have no way (short of genetic engineering on themselves) to act on the information.
That's just silly. Suppose that some manned mission to Mars were to find crates and crates of hand-copied volumes of Jane Eyre just sitting around on the sand. And suppose, after careful study by a team of experts, it was found that the books weren't all identical; that, in fact, there were minor differences between them and, so far as the experts could tell, no two copies were alike. Further, by doing some detailed statistical analysis, they were to determine that (to within some margin of error) all of the differences between the books could be explained by random processes, and anounced this as their explanation.
Suppose further (but just a little bit further) they were accused of missing the main question, and by defining the question to be "why do these books vary", producing a theory with no predictive or explanatory power. If they responded "my definition is superior in explanatory value because it is measurable," would you just accept it?
I have read On the Origin of Species cover to cover twice, and a few things are clear:
I appologize for the probably higher level of typos in this post; I've had a sick one-year old sleeping on my lap through most of it.
--MarkusQ
[1] Unless you're going to drag in some sort of anthropic argument.