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Professor Henry Harpending lead the research that revealed that humans are evolving at a rate hundreds to even thousands of times quicker than in their early history. He teaches Anthropology at the University of Utah.
Homely Homo sapiens are evolving hundreds to thousands of times faster than in their early history

Many who discredit evolution due to lack of evidence or theistic reasons may be powerfully startled by how much evolution is smacking humanity in the face. Humans are evolving at frenetic, previously unobserved pace according to a new paper titled "Recent acceleration of human adaptive evolution", which was published Monday in the peer-reviewed Proceedings of the National Academy of Sciences (PNAS) journal.

The paper, which was based on research spearheaded by University of Utah anthropologist Henry Harpending, examined 3.9 million gene segments of 270 individuals, 90 of European descent, 90 of African descent, 45 of Han Chinese descent and 45 of Japanese descent.  The conclusion was that humans evolved rapidly, and apart from each other. 

Evidence indicates that this rapid evolution has not stopped either.

If the human genome had evolved at the current pace during the period of 6 million years since the human lineage separated from the Chimpanzee lineage, as is currently believed, than there should have been 160 times the current number of genetic variations in human DNA.   Further by comparing dental and skeletal variations of the last 10,000 years of human history, the team came to the conclusion that man underwent a relatively slow paced change over the first couple of million years, but is now entering into an era of unprecedented evolution, which would explain why the current rate is so much higher than the previous rate.

The study cites large separated populations as a tremendous factor for the increase in evolution.  For example, a U.S. state has millions of citizens.  If a significant portion of these people stay inside the state, Harpending predicts that we should see tremendous genetic variation occur between these people and the people in the adjacent state -- as much change as you would see in the entire smaller population human population a million years ago. 

The study indicates people today exhibit as much genetic variation from Homo sapiens 5,000 years ago as they do to Homo erectus, or Neanderthals.

Team leader Professor Harpending sees the research as pushing a revolutionary fundamental change to the general public perception and understanding of evolution.  Says Harpending, "I was raised with the belief that modern humans showed up 40,000 to 50,000 years ago and haven't changed.  The opposite seems to be true.  Our species is not static."

Harpending says that while no one is going to see change occur in their lifetime, over thousands of years major changes have and will continue to occur in human being's physiology and in genes related to social factors and intelligence.  Such changes will have a profound effect on how humans behave in society and how they interact with the world around them.

The study also points to how geographic location has influenced humans, like many animals to adapt and evolve via natural selection.  For example human skin lightened among population groups in farther northern or southern lying regions in order absorb more Vitamin D in cold areas with less sunlight.  While factors like this may cause humans to evolve together in a sense to deal with certain common obstacles, the research also notes that the actually genetic adaptation, while superficially similar can be very different due to geographic and social population isolation. 

A good example of this phenomena is that a bat, a bee and a bird, can all fly (all have wings and lightweight bodies) but the actually chemical and fine-level physical mechanics are very different.  Similarly, the study discusses how the adaptation of lightened skin color is implemented by different genetic changes in the Asian and in the European populations, despite the superficially similar result.

The research of the oft-published Harpending and his colleagues are stirring up the genetic community and should bring some really exciting change to how we view evolution, society, and a broad array of other fields.

Harpending warns not to get too hung up on the societal implementations of the research.  He emphasizes that unlike fellow genetic researcher Watson, the researcher of DNA-helix fame whose controversial comments on race and intelligence landed him in a boatload of hot water, he believes that he sees no genetic evidence that any specific population group is evolving to be "better" than the others. 

In an interview, he says, "Some of the mutations let us do better. We can eat simple carbohydrates, which hunter-gatherers never did. But we may also be accumulating damaging stuff.  Evolution is a double-edged sword.  What evolution cares about is that I have more offspring. If you can do it by charming and manipulating, and I'm a hardworking farmer that's going to feed the kids ten years down the road, then you're going to win. Hit-and-run, irresponsible males are reproducing more. That isn't good for anyone except those males, but that's evolution."

Harpending's no-nonsense unbiased approach to genetics research is fortunate and essential as the topic is prone to fan some tremendous critical fires.  As he and his team continue to release insightful and groundbreaking research, hopefully society will take the research in the proper context and use it for the betterment of mankind applying it to useful fields such as biotech.

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genetic variation
By ethies on 12/12/2007 3:58:47 PM , Rating: 2
Is genetic variation the same thing as evolution? I mean, there's waaaay more of us now than at any other time in history so of course there should be more varition. I'm not sure exactly what he means to point out in saying this. We're more diverse compared to people 5000 years ago, yet we still we still look a lot more like egyptian statues than neanderthals. Maybe I'm confused.




RE: genetic variation
By KristopherKubicki (blog) on 12/12/2007 4:03:23 PM , Rating: 2
There's more to evolution than just superficial appearance. The ability to process simple carbs for example, is a monstrous and certainly evolutionary change.

And given that Ancient Egyptians usually topped out at about 5 feet tall, I'd have to disagree that we look all that similar!


RE: genetic variation
By ethies on 12/12/2007 4:16:13 PM , Rating: 3
I guess that's my point, we're supposedly more diverse yet there hasn't been that kind of kind of fundamental change anywhere.

Simply because they were short doesn't mean that we don't still resemble them more than we resemble neanderthals. Also, height is highly driven by nutrition levels. We've found that nutritional variances during youth accounts for a large part of height, and ancient egyptians were known for famine. I'm not saying we look identical, just a lot more than we look like neanderthals.


RE: genetic variation
By KristopherKubicki (blog) on 12/12/2007 4:20:56 PM , Rating: 1
There is an amazing theory called epi-genetics. It basically states that while we all have genetic markers "enabled" at birth, by introducing specific proteins and chemicals into our bodies we can actually disable / enable markers at will.

Some of the people who've done these studies also show signs that your "epi-genome" is also inherited.

So let's say I have a marker for cancer. It may be possible to disable that marker via diet and my environment. It may even be possible that my kids, who will inherit that marker might also have it disabled if its disabled in me.

Nutritional changes affect height, as you mentioned, but they may be affecting a whole lot more.


RE: genetic variation
By ethies on 12/12/2007 4:26:13 PM , Rating: 2
I've not heard of this, interesting. I've read that many genes influnce on our phenotype is not about if they are 'on' or 'off', but rather when they are on or off and for how long.

My real beef with this thing is I'm not sure I buy into:
Genetic Diversity = Evolution


RE: genetic variation
By BMFPitt on 12/12/2007 4:30:38 PM , Rating: 2
quote:
My real beef with this thing is I'm not sure I buy into:
Genetic Diversity = Evolution
Geographically separated races of humans diverged due to differing evolutionary pressures in their respective environments. What's not to buy into?


RE: genetic variation
By ethies on 12/12/2007 4:36:51 PM , Rating: 2
I know what you mean. I guess I should have said that differently. We are no longer a world divided. People from all different races have children with one another. Is the simple novelty of combinations of genes not previously expressed together evolution? Or is it neccessary for these combinations to meet a purpose of change and adaptation for it to be considered evolution. I guess I'd side with the latter. Otherwise every single child produced is an example of evolution.


RE: genetic variation
By masher2 (blog) on 12/12/2007 4:55:01 PM , Rating: 2
Evolution is the change in frequency of certain characteristics. It's more than an expression of diversity; it indicates that some characteristics are becoming more or less common in the general population.

It's really not surprising to me that evolution is occurring so much faster. Technology has removed the maintaining pressure of natural selection. Now, genetic drift is quickly taking the human genome to uncharted territory.


RE: genetic variation
By JCheng on 12/12/2007 5:02:02 PM , Rating: 2
You're just describing natural selection, not evolution. For evolution you need to add mutation, that is, the introduction of new traits.


RE: genetic variation
By phattyboombatty on 12/12/2007 5:27:15 PM , Rating: 2
No, he properly described evolution. Mutation is one of several effects that causes gene variation, and the definition of evolution does not depend on mutation occurring.


RE: genetic variation
By masher2 (blog) on 12/12/2007 5:29:11 PM , Rating: 2
My apologies; I didn't see your post before submitting my own.


RE: genetic variation
By masher2 (blog) on 12/12/2007 5:28:28 PM , Rating: 2
Wrong on a few counts. Firstly, evolution doesn't imply the introduction of wholly new traits. If an existing trait becomes substantially more or less common, the species has evolved...albeit slightly.

Secondly, mutation is simply one of the three primary factors which causes evolution, natural selection and genetic drift being the other two.

Thirdly, mutation isn't required to bring about new characteristics. Both selection and drift can do so as well...though not so rapidly as mutation can, obviously.


RE: genetic variation
By odessit740 on 12/12/2007 6:15:27 PM , Rating: 3
Evolution is the change in allele frequency over time.

In addition to mutation there is also recombination, selfish genes, and selfish groups of genes.

Selection and Drift are the two primary forces that act upon populations to produce evolution, much more so than mutations.

Selection relies on large populations, while Drift is most effective in small populations.

PNAS is one of the most highly accredited peer-reviewed scientific journals, so I trust what they include in their publications. The probability of this being bogus is small.


RE: genetic variation
By AWeav09 on 12/12/2007 7:36:21 PM , Rating: 2
You are treating natural selection and mutation like they are two entirely different forces, but in reality they work together to cause evolution. When a gene experiences a mutation, it can be beneficial to the organism, harmful to the organism, or it can have no significant effect. This is where natural selection comes into play - a beneficial mutation may allow the organism to have more offspring, thus passing along more of their genes than would another organism without the mutation.

While you are correct in claiming that natural selection is a primary evolution-producing force, downplaying the importance of mutation in the same sentence is ignorant.


RE: genetic variation
By masher2 (blog) on 12/12/2007 8:08:26 PM , Rating: 2
> "You are treating natural selection and mutation like they are two entirely different forces, but in reality they work together to cause evolution"

They *are* two different forces, and yes they (along with genetic drift) work together to cause evolution. Which is what my original post stated.

> "downplaying the importance of mutation in the same sentence is ignorant. "

But I didn't "downplay" mutation at all. I merely pointed out that mutation isn't the only force which can create new characteristics.


RE: genetic variation
By AWeav09 on 12/12/2007 10:24:12 PM , Rating: 2
I'm sorry, I meant to reply to odessit's post, not yours.


RE: genetic variation
By rcc on 12/13/2007 3:12:39 PM , Rating: 2
quote:
While you are correct in claiming that natural selection is a primary evolution-producing force,


The role of natural selection has been greatly reduced, at least in more developed countries. The traits that allow greater reproduction still have a large effect. But those that "trimmed" the undesirable traits have been nullified to a great degree by medicine and over protective societies. : )


RE: genetic variation
By geddarkstorm on 12/13/2007 1:10:38 PM , Rating: 3
Oh, I think that whole "selfish gene" postulation (it isn't even a testable hypothesis last I heard) is absolute garbage. Selection does not occur on the gene level, but on the population level: the survival of any one gene depends utterly on the survival of the organism and genome it is in which in turn is determined by the combinations of all genes, regulatory elements, and structure of that genome (and random chance) for successful propagation to successive generations. Moreover, it's been shown that bacterial genomes are greatly shrinking over time, and any unneeded genes for a nitch a bacteria finds itself in are cut out and eliminated from the genome (see Mycoplasma), so that if a gene is preserved it has to have some function that is useful to the bacteria and which elimination of will be deleterious (that function can be on the population level, such as a switch from a host to non-host environment requires totally different genes, so even if one individual bacteria has been in a host for all its life, the life cycle of the species and population as a whole requires those non-host genes for continual survival).

Transposons seem to be a favorite of the "Selfish gene" examples I've seen, but transposons play a critical role in genetics, especially bacterial, where recombinational events such as the aforementioned deletion of genes, is greatly enhanced and driven by the presence of transposons. Transposons also act as platforms for the formation of pathogenicity islands and where multiple drug resistance genes can be incorporated into easily via cassets and recombination; and then transposons, due to their ability to move, can jump to plasmids and be shared with other bacteria (through conjugation, transduction, or for those that are naturally competent, transformation). This makes transposons one of the most powerful genetic manipulation tools in the bacterial arsenal (same for us, though they play less of a role due to the size and complexity of the genome). Notwithstanding, that if a transposon becomes deleterious, it is eliminated like any other gene.

In eukaryots, humans, it's recently come to light that "junk DNA" is not necessarily junk, but often encodes for small RNAs instead of proteins, which serve a variety of functions (i.e. the 7SL RNA used in secretion tag recognition by the SRP system, and RNAi). Moreover, intergenic regions often have vital roles in the regulation of gene expression by the impact of the spacing of enhancer elements, promotors, and local regulatory elements; where any change in base pair distances can negatively or positively affection expression rates of a gene even in temporal settings. Furthermore, studies of chromatin structure are beginning to paint the picture that intergenic regions are very important for affecting the layout and loading of histones throughout the DNA, as well as methylation patters which affect condensation such as the switch from euchromatin to heterochromatin, or even packing of chromatin into the hypercondensed chromosomes seen during mitosis/meiosis. IS elements, or satellite DNA, are also great sites for recombination events between non-homologous chromosomes as often they are the only shared homology between them; and we all know recombination is the fastest way to create genetic diversity.

Sorry for the rant, but that whole notion that genes are some how individuals trying to survive just bugs me. A single gene by itself is nothing, and all a gene is is code for making protein.


RE: genetic variation
By DerwenArtos12 on 12/13/2007 2:00:05 AM , Rating: 2
You're taking the term genetic diversity to mean that there is a diverse population of genetic combinations. What the author is using genetic diversity to imply is the broadening gap between our basic genetic commonalities and those of our ancestors.


RE: genetic variation
By Ryanman on 12/15/2007 3:59:58 PM , Rating: 1
We're talking about evolution though. Interracial sex has been going on for a long time, but definitely not as long as you'd thinkg. It's been a mere 500-1000 years since ships, planes, etc. etc. etc. made racial mixing so much easier. We aren't a world divided anymore, but evolution-scale wise I still think we have yet to see those effects.


RE: genetic variation
By shecknoscopy on 12/12/2007 8:39:53 PM , Rating: 3
quote:
There is an amazing theory called epi-genetics. It basically states that while we all have genetic markers "enabled" at birth, by introducing specific proteins and chemicals into our bodies we can actually disable / enable markers at will.


Actually epigenetics is far more than a theory, it's an observable (and rather wide) field of research. Briefly, epigenetics refers to any heritable trait (i.e., which can be passed from parent to offspring, as would be with a gene) which is NOT due to the chemical sequence of your DNA. At first glimpse, you might imagine, "well, if we can get traits through means other than the sequence of our DNA, then haven't we refuted the so-called purpose of DNA in the first place?" No so much.

To illustrate, I'll give two brief examples.

First, consider that each and every one of your cells has ~six meters of DNA in them, if we were to stretch the molecules out and lay them end-to-end. However, each cell is only about 50-100 micrometers wide (and the nucleus is even smaller), so when you make a new cell, you have to package your DNA inside a very tight space. Picture a long length of yarn being wound up around itself to make a ball.

Now, in order for a particular gene to be useful, there are molecular machines to have to physically bind to, and process the patch of DNA corresponding to that given gene. If this gene has been "wound up" in the very center of our "ball of yarn," it's going to be substantially harder for the machinery to get to it, and do its job, as opposed to a schenario where it's closer to the surface of the ball. So, if two individuals have the exact same sequence of DNA corresponding to this gene, but one individual's cells have packed it so as to be more accessible, but the other's have buried it in their core, then the two people will show different traints for this gene, even though the DNA is identical. This is epigentics.

(An interesting side note: true calico cats can only be female, and the reason why deals with epigentic control of a certain gene, much as described above.)

The second example is probably more familiar. Prions - proteins which can adopt two drastically different shapes, and in one shape can catalyze the self-assembly of long protein fibrils - are an epigenetic phenomenon. Mad-Cow disease is probably the most famous prion, and indeed all known examples in humans are horrific, lethal diseases. However, in yeast there are numerous known prions which dramatically change the organism's ability to react to its environment, but which are completely nontoxic (and certainly nonlethal) to the cell. These can be genetically passed on from parent to offspring, but - as the trait is linked only to the fold of a protein - has nothing to do with the sequence of DNA. Hence, it is an epigenetic phenomenon.

...and also forbodes of the horrible day we discover "Mad Yeast Disease," forcing us to purge our society of bread and beer. May God have mercy on our souls.


RE: genetic variation
By MrPickins on 12/13/2007 10:40:10 AM , Rating: 2
quote:
Actually epigenetics is far more than a theory, it's an observable (and rather wide) field of research.


Kind of like the Theory of Relativity, The Theory of Evolution, Quantum Field Theory, The Theory of Plate Tectonics, ect.

You sound like an intelligent person. You should already know that in science Theory != Hypothesis.


RE: genetic variation
By retrospooty on 12/13/2007 11:02:05 AM , Rating: 2
Things gain the name theory when they are a theory, and often the name "theory" stick.

The theory of evolution is still called the "theory", but it is proven, just a linguistical error. Scientifically speaking Evolutiona nd plate tectonics are not "theories" they are proven facts. Relativity, and quantome filed... Who knows, I thing we have a long way to go to absolutley prove either.


RE: genetic variation
By MrPickins on 12/13/2007 11:15:15 AM , Rating: 2
No.

http://en.wikipedia.org/wiki/Theory
quote:
In scientific usage, a theory does not mean an unsubstantiated guess or hunch, as it can in everyday speech. A theory is a logically self-consistent model or framework for describing the behavior of a related set of natural or social phenomena. It originates from or is supported by experimental evidence (see scientific method). In this sense, a theory is a systematic and formalized expression of all previous observations, and is predictive, logical, and testable. As such, scientific theories are essentially the equivalent of what everyday speech refers to as facts. In principle, scientific theories are always tentative, and subject to corrections or inclusion in a yet wider theory. Commonly, a large number of more specific hypotheses may be logically bound together by just one or two theories. As a general rule for use of the term, theories tend to deal with much broader sets of universals than do hypotheses, which ordinarily deal with much more specific sets of phenomena or specific applications of a theory.


I know wikipedia isn't the best source of info in the world, but it is more than accurate in this case.

Read up on the scientific method.


RE: genetic variation
By retrospooty on 12/13/2007 1:17:48 PM , Rating: 2
OK, point taken on the language...

My point is that evolution is a proven fact. I thought you were debating that fact and saying it is not yet proven. It is, and has been for quite a while.


RE: genetic variation
By Spyvie on 12/13/2007 11:28:24 PM , Rating: 2
Evolution and natural selection are obvious truths, but the theory of evolution does nothing to explain the origin of life on earth. I think we frequently loose sight of that fact.

I submit that there is absolutely no evidence supporting any theory regarding what happened in the primordial soup. The theory of evolution (fact of natural selection) is frequently inserted here as something for the layman to grasp, even if it's validity is only in place because nothing else makes sense... and that's exactly the same reason used to embrace a creator model.


RE: genetic variation
By Spyvie on 12/13/2007 11:32:57 PM , Rating: 2
The fact that I mistakenly used the word loose instead of lose may illustrate my carelessness, but does not invalidate my comment. :)


RE: genetic variation
By MrPickins on 12/14/2007 12:40:44 PM , Rating: 2
quote:
My point is that evolution is a proven fact.


Mine too. :-D

All too often I hear: "But evolution's just a theory!"


RE: genetic variation
By shecknoscopy on 12/13/2007 11:23:58 AM , Rating: 2
quote:
Kind of like the Theory of Relativity, The Theory of Evolution, Quantum Field Theory, The Theory of Plate Tectonics, ect.


quote:
You sound like an intelligent person. You should already know that in science Theory != Hypothesis.


Oh yeah, but I put in the correction here for two reasons. First, though the Quantum Theory, Theory of Evolution, etc... are terms which have become lexiconized, and hence are pretty much idiomatic, the same is not true of the "Theory of Epigenetics." That is, in a physics lecture, you might here a Quantum researcher refer to it as the Quantum theory, but the same would not be true of a geneticist talking about epigenetics.

The second reason is that, unlike the Quantum Theory, the Theory of Relativity, Evolution, (or heck, the Atomic Theory...), there's no cogent, unifying single thought that unifies epigenetics. It's not like "Hey, I wonder if energy can be quantized," or, "I wonder if the speed of light is the fastest speed at which any object with mass can travel." That is, there's no single thought from which all the other details of the field stem. It's just "I wonder if sometimes traits aren't purely the readout of the sequence of DNA." Yeah, it's unifying, but the details of how and when it holds true don't derive perfectly from this single insight. Like a lot of biology, the current state of the art is just to do a lot of experiments, and list all the examples you've found, with putative mechanisms.

Oh, and if possible, threaten to hold the city's water supply hostage with it. :)


RE: genetic variation
By MrPickins on 12/13/2007 12:14:07 PM , Rating: 2
I was pretty sure you knew the difference, I was mainly commenting on a misconception I hear all too often from the layperson.

Epigenetics probably would be a theory if there was some way to construct a usable model the interactions between proteins and DNA. Hell, just to understand the many folds is a daunting task.


RE: genetic variation
By InsaneGain on 12/12/2007 9:45:07 PM , Rating: 2
I always understood that the evolution of traits was solely driven by either survival or mate selection resulting in an increased chance for these traits to be passed on to future generations. I was thinking that evolution would slow to a complete standstill today, now that traits no longer have any bearing on whether or not an individual survives to pass their genes on. Regarding what you say about epi-genetics, am I correct in thinking that evolution is actually at least partially driven by the environment, directly affecting the genes in the germ cells? Is it possible that the evolution of light skin was caused not by increasing survival rates in northern latitudes, but by a lack of sunlight causing certain genes to be turned off or on, and that this change was then passed on to future generations? This would be an amazing revelation. I wonder if drug addicts or smokers can possibly pass on genetic issues to their children.


RE: genetic variation
By shecknoscopy on 12/12/2007 10:43:12 PM , Rating: 4
Well, the influence of environment on the evolutionary process is quite palpable; afterall, it's the population's reproductive fitness under certain selective stresses that determines survival/extinction, and hence how represented any genes will be in the next generation.

As for the other parts of your question, though, the answer is both "yes" and "no," sadly. In the "yarn ball" example I originally posted, we have a type of epigentic control that's effectively another attribute that we'd ascribe to the gene itself. I.e., it's not just the sequence, but how "accessible" it is to be read, which determines its final readout (the "phenotype" as we say in the 'biz.). One must wonder, however, as to what exactly caused the gene to be more or less accessible in different individuals. That is, what caused the epigenetic phenomenon? In some cases it's though to be stoichastic - the packaging of a gene in the nucleus of the cell is effectively just a random walk. In most cases, though, scientists either have some hazy proof that that's not quite the case, or just going on the intiution built up from our developments in molecular biology, would guess not. Things like this - intrinsic, requisite cellular phenomena - tend not to be left too much to chance.

So, we come back to the question: why are the epigenetics of a given gene different in two individuals? Maybe because there's another gene which controls the epigenetics of the first gene, and THIS gene is genetically different between the two. (I.e., there's a difference in the actual sequence of the DNA). Or maybe not.

A great illustration to this would be the multiple different types of tissues present in your body (or in any complex multicellular organism's body - from microscopic worms to plants, to animals and higher fungi, etc...). Your liver cells, stomach cells, muscles, brain tissue, eye photoreceptors, kidneys, etc.. all have *exactly* the same DNA in them (immuno cells are a little bit different, but who's counting?). And yet, there's *quite* a difference between a liver cell and a skin cell and a neuron, etc... Where did that difference arise?

There's epigenetic control which helps determine the creation of special tissue types during embryonic development. But how was this epigenetic control programmed? Genetically .

Of course, that genetic control of epigentic control could itself be partially controlled epigenetically, which could be controlled genetically, which..... and it's turtles all the way down...

So really, in many cases, epigenetics are just attribute which colors the "classical" genetics; the two are contributing factors which cannot be fully understood without taking the other into account.

The skin-color issue that you mentioned can actually be explained by the need to genetate vitamin D; this is done when the cells which line your cappilaries are hit with light, and that energy is used to synthesize the vitamin. If you're living on the planes of Africa, you get enough sunlight to do this by about 9am every morning (assuming you're topless, and you got up at about 8:30).* Hence the worry is more UV damage to the rest of your cells. So, darker skin is positively selected for so as to keep you from constantly having sunburn or getting melonoma. If you live in Norway, though, where at best ~10% of your body's skin is exposed to sunlight, and where the light is physically weaker in energy, then the selective pressure is negative for blocking out UV rays (which are in low abundnace), but positive for transparency, so as to allow more light in, and allow vitamin-D production.

So, selection can be either positive or negative, depending on its context, and the pressure/population in question. In the the case you mentioned, there's no need to explain it via environment interracting with epigenetics; plain old genetics would do just fine.

Drug addiction and/or smoking might be transmissable, but again, the issue of genetics vs. epigenetics is hard to say. The data on this are themselves kinda' weak. Also, smoking, drinking, and certain types of drug use are known to induce genetic alterations, so the likelihood that it'd be a genetic or epigenetic cause is harder to say

BUT, a nice example of the sort of thing you're talking about - where an enviromental cue directly interacts with epigenetics and changes the way an organism uses its genes - is in the sex determination of sea turtles. Unlike humans, where it's determined by chromosomal content (XY's are male, XX's are female, XXY's are kinda' weird males, etc...), male and female sea-turtles have the exact same DNA content. However, the temperature an egg is incubated at will untimately determine its gender - and that's because genes which respond to the environmental temperature cue directly influence which genes - the "maleness" genes or the "femaleness" ones - get used. If we imagine a scenario where the population needed to be biased toward more males or more females in order to stay evolutionarily fit, then we could imagine genetic changes in the temperature sensors which read out into epigenetic changes in the rest of the genome, etc...

As for the yeast prions, it turns out that the data are *much* clearer. Here, you might want to read up on what Susan Lindquist's lab (at MIT, formerly U. Chicago) has been doing. They find that yeasts which have a prion in the "off" state, and those which have them in the "on" state can adapt to the presence of certain toxins with different efficiencies, allowing them to live under conditions that their counterparts can't. She pitches the prion as a "capacitor for evolution," i.e. - it unmasks, or makes available, genetic variation that would otherwise be hidden, allowing for more facile selection. It's all quite cool, but still somewhat speculative. And, there's the issue of whether examples will be found outside of yeast.

*-A condition I only partially agree with


RE: genetic variation
By MBlueD on 12/13/2007 3:36:13 AM , Rating: 1
I'd rate you up if I could.


RE: genetic variation
By shecknoscopy on 12/13/2007 11:29:20 AM , Rating: 2
quote:
I'd rate you up if I could.


Awww, thanks. :) I'm just a biologist who's always excited when DailyTech mentions something in his field. The minute the discussion veers toward processor architecture, I cease to be even remotely useful.

Well, I guess I can still be sent out to get sandwiches, but it's not the same.


RE: genetic variation
By masher2 (blog) on 12/13/2007 12:01:00 PM , Rating: 2
I'll have mine on rye, thanks.


RE: genetic variation
By shecknoscopy on 12/13/2007 12:19:29 PM , Rating: 3
Alright, I've got a Reuben on Rye for Masher, Tuna salad on whole-grain for Gary Key and Kubricki's typical Monty Cristo with chocolate sauce. Any other takers? I'll be back with it as soon as I get Anand his latte.

(You know he beats me if it's too cold when it arrives.)

-Sheq


RE: genetic variation
By augiem on 12/13/2007 12:28:36 PM , Rating: 2
I'm not sure where this simple carbs theory comes from, but here's some common sense observations:

- Honey and fruit have been around forver. Not as simple as glucose, but still considered simple carbs.

- Every animal I know loves simple carbs. (They are high energy foods that pack on the fat.) My old pet African Grey parrot LOVES ice cream, Sunkist, you name it. Bears will raid trash from campers. What are they going for? Sweets and doritos and such. Now you're not going to tell me bears and african grey's have been eating our trash so long they evolved to eat ice cream and twinkies.

- If evolution's made us so good at eating simple carbs, why is America, the world's #1 sugar consumer per-capita, also the fattest nation on earth? Doesn't sound like we're too efficient at processing them. You could argue fat is evolutionarily beneficial for survival, but only to a certain degree. The health detriment starts very quickly once you start getting over a certain % overweight.


RE: genetic variation
By JasonMick (blog) on 12/12/2007 4:10:00 PM , Rating: 2
Basically, genetic variation aka mutation can be like you said a simple change, which can be good, bad, and sometimes even ugly. Natural selection, which the paper also extensively discusses is the repetitive selection and promotion of a certain group of individuals with a common trait resulting from such a mutation. For example, maybe your tongue can taste a flavor that no one else can -- but if this doesn't in some way leading to you having more offspring and your children with the trait having more offspring via health, wealth, etc than it is merely genetic variation and not natural selection.

Evolution is a rather vague term that is often applied in conflicting ways, but usually it refers to many changes (genetic variation) resulting from natural selection and/or genetic drift (random mutation in small isolated populations). Darwin's "On the Origin of Species" lays out the basic theory of evolution, sans the genetic drift part. The key criteria to label something as having evolved, is from my understanding is -- has the creature changed substantially enough, chemically, physiologically, and/or behaviorally due to genetic changes over X period of time that it has become substantially different from its ancestor, creature Y? If the answer is yes than the creature has evolved.


RE: genetic variation
By ethies on 12/12/2007 4:22:24 PM , Rating: 3
My point essentially is this:

If you sample from a larger population, genetic diversity should always be higher.

If you think about it, even without developing new traits like enhanced taste or predisposition towards cancer there are a lot of genes that can be changed. Consider a human as 1 trillion switches that can be in one state or another. If you look at a group of 1000 people, compared to a group of 10 people, there should nearly always be more diversity. Right?


RE: genetic variation
By Terberculosis on 12/12/2007 4:26:34 PM , Rating: 2
Thats true, but the definition of Evolution is changes in the genes expressed in a population, wether due to introduction of new genes or just changes in relative proportion of existing genes. So even though the increased variation is due to a larger sample size, it still counts as evolution, because the rates of expression and number of different versions of genes has changed in the population as a whole.


RE: genetic variation
By ethies on 12/12/2007 4:39:52 PM , Rating: 2
As in the above thread, I have a trouble with this definition of evolution. If your metric is simply expressing a novel combination of genes, then every child is an example of evolution.


RE: genetic variation
By Terberculosis on 12/12/2007 4:49:11 PM , Rating: 2
Nope, Evolution only counts as changes in a breeding population. If that new child introduces a novel gene, then its evolution for the population, or if it changes the distribution of genes in the population. If its just a little trailer park miracle that changes nothing, its not evolution, its reproduction.


RE: genetic variation
By ethies on 12/12/2007 4:53:00 PM , Rating: 3
Ok, then is Wilt Chamberlain an evolutionary force? The man has to have affected the distribution of genes!


RE: genetic variation
By Terberculosis on 12/12/2007 4:56:10 PM , Rating: 5
Yes.
The evolutionary forces are :
1. Natural Selection
2. Genetic Drift
3. Gene flow
4. Wilt Chamberlain


RE: genetic variation
By ethies on 12/12/2007 5:18:56 PM , Rating: 2
But that sort of brings us back to the original question. Is increased variation, which doesn't favor the expression of any particular gene or set of genes, an example of evolution? It certainly is variation. But without these pairings affecting the distribution of genes or introducing novel genes, it couldn't be called evolution right? Perhaps there is a genetic drift going on, or a selection for some yet unknown gene; but increased variation does not guarantee evolution no?


RE: genetic variation
By Terberculosis on 12/12/2007 5:27:11 PM , Rating: 2
Increased variation is the essence of Evolution. it doesnt matter if the increased variation actually does anything or not. It's still a change in gene expression in the population.

That increased variation allows the species to be more adaptable when the fitness landscape changes. (we have more variation now, so should some catastrophy occur, there is a greater chance that some combination of genes within this increased variability will be better able to cope.)

It's like evolution's version of studying for an exam during dead week. times are good, which leads to an increase in variation, when times get hard, the increased variation helps the population to survive.


RE: genetic variation
By ethies on 12/12/2007 5:40:10 PM , Rating: 2
Well damint, now you've got me confused. You've said that increased variation is the essence of evolution and that all increases in in variation improve the chances of the species' survival during hard times. Doesn't that mean that the aforementioned 'trailer park miracle,' as an increment of increased variation, could potentially improve the survivability of the species? Wouldn't that imply evolution again? {dizzy}


RE: genetic variation
By Terberculosis on 12/12/2007 5:46:14 PM , Rating: 2
quote:
If that new child introduces a novel gene, then its evolution for the population, or if it changes the distribution of genes in the population. If its just a little trailer park miracle that changes nothing, its not evolution, its reproduction.<\quote>

I said that if the child does change the amount of variation then its evolution. If the child does not change the amount of variation (if it say, has a genotype that is such that it introduces no new variation, or it has the same genes as the majority of the population) then it has not changed anything.

Just because there is a new child born, it does not necessarily introduce any increase in variation.


RE: genetic variation
By ethies on 12/12/2007 6:00:16 PM , Rating: 2
Save for identical twins (and clones I suppose), isn't each individual a unique combination of genes? Doesn't it then follow that these unique individuals contribute to the genetic diversity of the species?


RE: genetic variation
By masher2 (blog) on 12/12/2007 6:06:12 PM , Rating: 2
I think you're confusing sample size with diversity. A large population doesn't imply more diversity. Diversity is a measure of the variance from the mean. A population of three individuals can theoretically be more diverse than one with thirty.


RE: genetic variation
By ethies on 12/12/2007 6:22:23 PM , Rating: 2
The mixing of many different peoples ensures that many different genes are going to come in contact with each other. I work with cattle so I'll analogize with that. A herd of 50 head that have been maintained as a closed population will have a more homogeneous genotype than a herd of 3,000 maintained in the same fashion. The more individuals in the population, the more potential for genetic variation. The world has been maintained as a closed herd and as population increases, there are more opportunities for unique gene combinations.


RE: genetic variation
By ethies on 12/12/2007 4:29:20 PM , Rating: 2
I forgot to mention that I reject the idea that genetic variation is the same thing as mutation. Mutation is a form of genetic varation but so is my being heterozygous for dark hair while my father and mother were homozygotes for dark and light hair respectively.


RE: genetic variation
By Cygni on 12/12/2007 4:54:27 PM , Rating: 1
Mutation is any (non sexual, and therefore unintentional) change in the genetic sequence. All genetic variation is the direct result of mutation. They are not one in the same, but one is the direct result of another.


RE: genetic variation
By Terberculosis on 12/12/2007 4:59:42 PM , Rating: 2
Not all variation is caused by mutation, there are other forces... see above.


RE: genetic variation
By Cygni on 12/12/2007 6:35:12 PM , Rating: 4
No. Literally all variation seen on the planet earth in living creatures, every single moved, deleted, duplicated, mis-paired base is due to mutation.

Mutation is ANY change in a genome. Therefore, there is NO source of genetic variation in life other than mutation. Period.

You are likely confusing long term mutation with more focused population genetics, where the mixing of different gene pairings through sex creates increased genetic variation in subsequent generations. But those genetic differences in the various populations got there by one thing alone: Mutation.


RE: genetic variation
By jtemplin on 12/12/2007 10:45:03 PM , Rating: 4
This is intro to biology stuff here people. Mutation is the ultimate source of variation. Good looks Cygni. Evolution is a macro level effect. Mutation is what happens at the level of DNA--the micro level stuff--that ultimately gives rise to evolution. It can happen in other ways which have been mentioned already, but mutation is the only source of truly NEW genetic information. Everything else is just re-shuffling the deck so to speak.


Unfortunately...
By BMFPitt on 12/12/2007 3:28:36 PM , Rating: 2
I think enough of us here have seen Idiocracy... I have spent a lot of time thinking of a reason why that isn't the direction we're headed in, but can't come up with one. It seems like it's either we'll be genetically modified superhumans or marching morons in a few hundred generations.

I don't like either of those outcomes.




RE: Unfortunately...
By KristopherKubicki (blog) on 12/12/2007 3:41:21 PM , Rating: 1
I think the deep seeded human emotion for greed (lust, gluttony, what-have-you) tends to go hand in hand with intelligence.

Maybe a little mischief will save us from Idiocracy


RE: Unfortunately...
By MeTaedet on 12/12/2007 4:01:49 PM , Rating: 3
You don't like the idea of human beings being genetically modified so as to ensure greater happiness, intelligence, and general competence? Why, because then you'll have to strive extra hard to remain relevant and useful to society? Here's a hint: you won't be alive in a few hundred generations and thus you have nothing to worry about. You've committed a logical fallacy. What you did was to use your mind's powers of prospection and prescience to put yourself in the future in order to determine the goodness and utility of genetic modification, and you irrationally imagined the unpleasant and abject condition being upon you of having to compete with humans who were in every respect your better, and this caused you to feel discomfort, jealousy, and anxiety. The truth is that there is no valid or logical reason to fear the advancement of the human species, but, by the same token, there's also not much reason to desire it because it shouldn't benefit us, the current generation, in any way, that future generations should be more advanced than we.

I dislike the phrasing of this article and/or the research of this man for the reason that it is liable to give a naive and poorly educated person the false impression that human beings are evolving to a condition of superiority over contemporary man. This is not necessarily the case. While I have little reason to doubt that evolution is speeding up, I do doubt that we are advancing; given the nature and state of human societies, such human beings that if they had lived thousands of years ago +, would have died due to poor genetics, are now surviving and are being given opportunities at mating and passing on their crap genetic material because our society has a misguided system of morals which is only going to result in suffering occasioned by poor genetics for future generations. Actually, I predict that if conditions remain the same long enough, barring genetic manipulation, we will have two or more species of humans at some point in the future, one being vastly superior to the other. As it is, intelligent people feel compelled to mate with other intelligent people, beautiful people with other beautiful people, and the stupid and ugly mate with other similarly stupid and ugly people. One can foresee that if this should continue long enough, we'd have a large discrete and distinct group of saliently brilliant people, a group of beautiful people, and a group of people fit for an asylum or circus show. I grant, though, that my reasoning may be rather shallow and simplistic.

On a more tangential note:

Many, or most, of us human beings believe that every person has the right to reproduce, but the truth is that because the act of reproduction affects the created child and the rest of society, and because human beings do not - or should not be thought to - have the right to harm others at their pleasure, we don't have any such right. If you have Schizophrenia, or you are a midget, or you have a family history of Alzheimer's disease, you should have NO right to reproduce, since the act is liable to cause your child a great deal of suffering who shouldn't be - and even has the right not to be - subjected to straitened conditions because his parents selfishly wished to have a child. This doesn't sound nice, or warm and fuzzy, or after-school-special, but that's precisely because it doesn't conflict with the truth of reality. I'm sure I'll get flamed for having said that, but...


RE: Unfortunately...
By BMFPitt on 12/12/2007 4:26:53 PM , Rating: 2
quote:
Why, because then you'll have to strive extra hard to remain relevant and useful to society?
No, I think that it will result in a race of uniformity, which takes away a big part of what makes us human.


RE: Unfortunately...
By Terberculosis on 12/12/2007 4:30:43 PM , Rating: 2
I, for one, intend to be alive in a few hundred generations. The lord is returning soon, and we shall all live forever with him.


RE: Unfortunately...
By TITAN1080 on 12/12/07, Rating: -1
RE: Unfortunately...
By Terberculosis on 12/12/2007 4:37:35 PM , Rating: 2
It looks like someone has stairs in their house.

Has this not become a bannable offence here yet?


RE: Unfortunately...
By KristopherKubicki (blog) on 12/12/2007 4:38:39 PM , Rating: 1
Getting close...


RE: Unfortunately...
By Terberculosis on 12/12/2007 4:46:57 PM , Rating: 2
Thats a real shame, I have always felt it was a very clever and worthwhile contribution to conversation.


RE: Unfortunately...
By KristopherKubicki (blog) on 12/12/2007 4:53:06 PM , Rating: 1
You were talking about Titan right? This is admittedly the worst forum for scarcasm.


RE: Unfortunately...
By Terberculosis on 12/12/2007 4:58:03 PM , Rating: 1
I was talking about titan, yes.

I have noticed the lack of ability to read sarcasm on these boards, but I dont take offense to it.
Some might even say I have used that fact to have fun with people a time or two. Luckily, I've found Jesus, and mended my sinful ways.


RE: Unfortunately...
By nayy on 12/12/2007 6:16:36 PM , Rating: 2
The problem is that here in DT some times you can't tell if the poster is being sarcastic or just dumb (more often than not is the latter).
A simple "/sarcasm" can save you from a few worthless discussions.


RE: Unfortunately...
By Ringold on 12/12/2007 4:36:21 PM , Rating: 3
quote:
As it is, intelligent people feel compelled to mate with other intelligent people, beautiful people with other beautiful people, and the stupid and ugly mate with other similarly stupid and ugly people.


There's one critical flaw in that two population theory. That is that intelligent people feel compelled to mate at all.

Well, they feel compelled to engage in the act of mating, but statistics show the highest achievers in society have the fewest kids. It's the dredges of society that pop kids out like an assembly line in developed nations. Having children takes time away from a career, personal advacenement, personal enjoyment.. and plenty choose not to bother.

Seems to me like the more likely outcome will be a very tiny superior population running like hell to the Moon and Mars, if one survives at all.


RE: Unfortunately...
By KristopherKubicki (blog) on 12/12/2007 4:45:57 PM , Rating: 2
quote:
Well, they feel compelled to engage in the act of mating, but statistics show the highest achievers in society have the fewest kids.

But is also a statistic fact that those kids tend to also become the highest achievers in their generation (with exceptions of course).

If anything, it's the foundations for genetically-"sound" racism. And we've only been dealing with that for a few millenia...


RE: Unfortunately...
By Terberculosis on 12/12/2007 4:53:13 PM , Rating: 2
Unfortunately, intelligence isn't a simple combination of genes.

Last I heard, most geneticists rejected the idea of our population splitting into two subspecies, one intelligent and one not. There are simply too many variables for the breeding populations to ever seperate totally.

In adittion, one intelligent man sireing a child from a non intelligent prostitute every few years should provide enough gene flow back and forth to keep the populations on similar footing.


RE: Unfortunately...
By phattyboombatty on 12/12/2007 5:42:11 PM , Rating: 3
Not to mention there's some damn fine looking women in the world that aren't too bright that most men (intelligent or not) would love to mate with.


RE: Unfortunately...
By clovell on 12/12/2007 4:55:57 PM , Rating: 3
After reading that, Ringold, I have to question which is actually the higher evolution of humanity - by your own comments, it seems as though the uneducated are more altruistic.


RE: Unfortunately...
By Ringold on 12/13/2007 4:38:15 AM , Rating: 2
I wouldn't necessarily disagree with that. ;)

I'm not advocating seperating groups, but just an observation. High achievers don't reproduce, so whatever genetic component makes them high achievers will not be passed on. Low achievers, though at the bottom of the income scales in developed countries, on the other hand, have lots of children. If it all has to do with nurture, then hey, no problem, it's a cultural issue. If there's a genetic component, then there's only one way that ends up. As for the running to Mars bit, well, it happened with 'white flight' as inner city crime spikes, so I figured it a safe assumption it'd happen again.

Don't pass any quick judgement, though, I'm about the only one at DT that commonly questions the push for GW when around 800 million people suffer chronic hunger when all they need is a job making us shoes (or insert random other low value added mfg job), for example.


RE: Unfortunately...
By wrekd on 12/13/2007 5:20:51 AM , Rating: 2
I see a lot of people tiptoeing around with terms like intelligent, high achievers, and educated. Isn’t all this really just subjectively bias towards those formally educated in some form? Just because some person may only have a few thousand words at their disposal and no need to count to more than a hundred, does not make them less of anything.

The key to survival is being in balance with your environment. Will being a CEO with a double masters degree help you during a cataclysm? I’m betting most brain surgeons commute to work, and get food from the grocery store. The question is, can your environment support you after an earthquake, meteor strike, or super-flu pandemic?


RE: Unfortunately...
By marvdmartian on 12/13/2007 9:35:45 AM , Rating: 2
That will be the minority evolutionary chain.

The majority evolution chain will be the 58IQ, obese, lackadaisical types that spend 1/2 their time talking to their friends on the phone (or texting them, natch!), and the other half of the time making babies that they can't afford to raise. Within 3 generations after the minority evolutionaries leave, the planet will resemble an area with a lemming invasion going on, and society will simply collapse upon itself, thus ending the dynasty of man upon the earth.

It's only many generations later that the minority humans will return to the earth, to find that the lizards have taken over.......or was it the cockroaches??


RE: Unfortunately...
By clovell on 12/12/2007 5:18:05 PM , Rating: 3
And what would you do? Sterilize those people? Then you won't have to worry about population control, because you'll have massive revolutions across the globe. Hysteria in the streets. Feminists sharing common ground with conservatives. Basically the end of civilization as we know it (sorry, just had to have some fun with it).

Having a child isn't inherently selfish, as most parents aren't aware of the risk factors they possess. And, considering the advances being made in laboratory fertility treatments, these parents may sooner be able to have children free from such genetic defects before they need worry about sterilization.

Furthermore, suffering is part of life. There's not one person on this planet who hasn't suffered. Should driving a car, speaking your mind, and owning a gun not be a right because they have the potential to cause suffering?

As for how having a non-'normal' child hurts society, I won't address the claim since you didn't substantiate it.

The Eugenics movement was struck down in the 20th century by most of the world. It was part of the foundation of the idea of a 'master race'. Call me crazy, but I think those ideas you're advocating have caused far more hurt and suffering throughout the course of human history than the idea that reproduction is a right.

That's my two cents.


RE: Unfortunately...
By Lazarus Dark on 12/13/2007 11:31:53 AM , Rating: 2
quote:
Should driving a car, speaking your mind, and owning a gun not be a right because they have the potential to cause suffering?

There's where you are mistaken. According to the government, these are "priviledges". You have no rights. Unless you pay for them (taxes, fines, tariffs, etc.). Those who cannot afford it have no rights.


RE: Unfortunately...
By clovell on 12/13/2007 6:18:16 PM , Rating: 2
Driving a car may not have been the best example, but the Bill of Rights, in fact, gaurantees the right of American citizens to own guns ad speak their mind.


RE: Unfortunately...
By JoshuaBuss on 12/12/07, Rating: -1
Every few generations...
By Hypernova on 12/12/2007 3:10:37 PM , Rating: 3
Evolution takes a leap...




RE: Every few generations...
By KeithTalent on 12/12/2007 3:35:14 PM , Rating: 5
It's funny, after surfing through Youtube and/or Myspace (plus others) for a few minutes, I would actually be inclined to say we were devolving.

Very interesting article though.

KT