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Humans Evolving Faster Than Ever
Kwyj1b0 writes "In a massive study on genetic variation among humans, researchers found that most changes have occurred in the last 200 generations, too fast for natural selection to catch up. Recent papers show that rare genetic variations have a more drastic effect than previously believed. Another result shows that 'we carry a much larger load of deleterious variants' (as well as positive variants) than our ancestors 200 generations ago."
Acquisition of mutations is not evolution. Evolution is the combination of variations AND selection of those traits that increase fitness. The fact that we only acquire more genetic mutations means that selectionhas gone down and evolution with it. The simple explanation is that healt care enabled us to cheat on selection.
If an experiment works, something has gone wrong.
"we carry a much larger load of deleterious variants"
My ex wife is finally explained!
...that it's because in the last 200 years humans have had to live with exposure to chemicals that no life, not even our single-celled ancestors, had to evolve in the presence of... so now we don't have the tools in our genetic toolkit to deal with the effects of those substances that are completely alien to this particular Earth-bound strain of life?
Just a thought.
This space available.
Any odds that, instead of or in addition to the rate of mutation going faster, the survival rate has also increased over the same period?
It's "Survival of the Fit-enough"... no longer "survival of the fittest".
With medical technology - babies that would have died lived on. They had families of their own. Thus, passing along 'defects'/'evolutions' which would have died out as those babies would not have made it to a reproduction age.
Doomed by our technology which was designed to save us.
Intelligence, technological capability, social abilities, and economic abilities are the traits being selected. They allow us to survive past our "natural" lifespans and allow us to breed when we would otherwise be unable to breed (e.g. fertility treatments). Whether these traits will remain selected rests entirely on us. We basically have traits and abilities that *may* allow us to transcend evolution, but the jury is still out on that one.
If we are unable to modify our own genetics in order to survive into the future, we are less capable of surviving at all thanks to the intelligence mutations...
Another result shows that 'we carry a much larger load of deleterious variants' (as well as positive variants) than our ancestors 200 generations ago."
Anyone who is familiar with and has read some of the comments on Slashdot could've told you *that*! Hell, "Idiocracy" is a documentary film!
Did someone actually pay these people for this "research"?
A Dire Straights song comes to mind. No, it's not "Sultans of Swing".
Strat
Progressivism (aka US 'Liberalism'): Ideas so good they need a police/surveillance-state to enforce.
....but I think we all know where evolution is headed.
This whole thread.
Hooray
This study obviously did not include most of the humans I encounter on a daily basis.
I think population dynamics show that in times of plenty (little natural selection, abundant food) populations explode, what the human population has been doing the last 100+ years. It's the spring that doesn't come or massive outbreak of disease or new dominant predator that culls the population, when that selection occurs the random genetic variations may give rise to competitive advantages. It is only after the population goes through the selection event that any mutations that proved advantageous will spread right through the population, then the population has evolved. Before the selection event the population is just randomly diverging.
Absolutely true!
Evolution works that way: In good times, a big population is generated that has great genetic variety. When bad times come along, the bad genetic variations will be removed from the population.
Suppose for instance that suddenly tomorrow all oaktrees had pollen that is deadly to most humans. The genetic variations builtup over the last 200 years might have provided a (possibly small) percentage of the population that is resistant to the deadly pollen. The result would be that a small group survives and starts working on a new gene-pool.
Yes, genetically we have been living in "good times" the last generations. More and more "slight defects" in the genetic pool are able to survive into mature ages.
A friend is totally colorblind. A genetic disadvantage, you'd say? Nope, his "grayvision" is a LOT better than that of most of us. Apparently he can spot camouflaged army-material from way further away than us normal people. When suddenly THAT becomes a winning trait (i.e. those that don't have it die), his descendants will form a larger part of the population.
This expansion of the gene pool also allows for combinations. Suppose the guy with the super-vision marries the gal with the super hearing?
Now that we can identify who is genetically and mentally inferior (with real science), and we have a ridiculous human population, why don't we bring back slavery?
if you read the posts on the submission page, it rapidly "devolves" (get it) into a spirited converesation on eugenics, which i read till i could no longer view Nazi Hate Speech.
i didnt read, but am assuming there some lovely eugenics in the /. comments, but im too sicked and scared to find out .....
depend on your environment sometimes. For example, heterozygous mutations in the gene that lead to cystic fibrosis probably increase resistance to cholera (by lowering electrolyte loss in the gut). Eliminate cholera in the modern world and the advantage apparently disappears. Similar for sickle cell anemia and malaria (depending of course, where you live or travel, this may still be highly relevant for you). And "fit enough" has always been good enough throughout evolution.
This is probably why primates need vitamin C, since we all lived in an environment with plenty of it and there was no selection against loss of the gene which occurred in one of our ancestors.
It is sometimes difficult to see the advantage of a particular mutation (resistance to dioxins because cytochromes don't metabolize them) or other mutations which are only beneficial in combination with others. Mutations in FoxP2 http://en.wikipedia.org/wiki/FOXP2 plus others probably led to human speech. There are rare individuals with mutations in a gene which regulates LDL (the "bad" cholesterol) http://en.wikipedia.org/wiki/Familial_hypercholesterolemia#PCSK9 that have very low LDL levels and are apparently perfectly healthy. They lack a gene most of us have and can eat a "modern" diet with a dramatically reduced cardiovascular risk. This is one of the ways in which speciation occurs.
200 generations....well, that's not a very specific amount of time, so I can't really comment on that specifically, but I wonder if it the whole "more rare genetic variations" has something to do with having bigger and more diverse populations inter-mixing. If there's a general trend in the last couple hundred to couple thousand years, it's that you've got people clumping together in bigger groups, developing complex trade and migration, all of it adding up to a much broader gene pool than the days of the hunter-gatherers going around in relatively closely related groups of 100-200 people, and that in turn leading to a much big genetic variety.
As usual, theocratic dogmas, rigorously enforced, frequently have unintended consequences. In the case of the dogma of heterogeneity there is the unintended consequence which evolutionary dynamics calls "horizontal transmission". Horizontal transmission is a mode of evolutionary success is based on, what in the vernacular we might call, "hit and run": The evolutionary fate of a stationary system (organism or ecosystem) is decoupled that of another, temporarily co-located, but mobile, replicator.
The result is always the same: The mobile replicator's evolutionary optimum is to totally disregard the viability of its temporary "partner" since it does not share in the fate of the "partner". This relationship is sometimes called "parasitism". That, in an age of jumbo-jet air transport, we might see such evolutionary dynamics play out is as inevitable as it is "sinful" to even think about.
The religious dogma demands that heterogeneity be thought of as evolving only "symbiosis", not "parasitism". This would be the case if there were no escape route for the immigrant replicators -- as they would be forced into "vertical transmission" which, in the vernacular means "sleeping in the bed you made for yourself (and others)". Even if we were somehow able to shut off further migration after allowing immigration, the costs of evolving symbiosis are profound: The vast majority of the immobile heterogenous ecologies resulting from the initial period of immigration would include at least a few replicators that might be thought of as "defectors" in an evolutionary prisoner's dilemma. Therefore the vast majority of ecologies would experience at least pathology if not death outright.
Seastead this.
> Akey’s group found that rare variations tended to be relatively new, with some 73 percent of all genetic variation arising in just the last 5,000 years. Of variations that seem likely to cause harm, a full 91 percent emerged in this time.
If we regress linearly, there were no harmful variations 5000/0.91=5494 years ago, which must have been the year Adam fathered Cain ;-)
So C = K/H, where C is the cost, k is a constant and h is the health of the baby.
1) What units is H in? (10 marks)
2) Taking into account your previous answer, when C is in inflation adjusted New Zealand dollars what is the value of K? (15i marks)
Confucius say, "Find worm in apple - bad. Find half a worm - worse."
If this discussion is any indicator, it's devolution that's accelerating.
The level at which Homo Sapiens are affected by natural selection has steadily declined, since at least the advent of medicine, probably since the advent of the type of intelligence we posses, possibly even since the earliest vestiges of the ability to have empathy for another. Every generation has more humans who live and procreate, who would have previously perished as children or very young adults. The affect that Natural Selection has on the human race diminishes constantly. Other animals that are affected by this would be any domesticated animal. Dogs, cats, cattle. sheep etc.. If it is a domesticated animal, we have more effect on their evoution than natural selection does. We decide which domestical animals are "worth" allowing to breed, and keep others from breeding. We decide which ones should be "put down" We decide whether our pets are spayed or castrated. We also have more effect on the natural selection of plants we domesticate. There are probably house plants that would have gone extinct if we didn't like them. Banana trees are this point cannot reproduce without human cultivation. The effect we, as a species, have on everything around us seriously alters the function of natural selection. Natural Selection may never have zero effect on human evolution, since new diseases will keep cropping up, and those with immunity will survive to procreate, and those without immunity will die (but only until such time as science comes up with a cure or a vaccine.)
200 generations, at 30 years per generation is 6000 years.
Or is the age between generations less than that?
Help! I'm a slashdot refugee.
This statement appears to reflect a misunderstanding of how evolution plays out in practice.
The way evolution is often taught is that the small genetic changes in each generation make a difference to the evolutionary fitness (relative to his/her peers) of the individual right away, but that the changes are so small that it takes very many generations to see divergence of sub-populations of the species and hence noticeable evolutionary change.
The reality of evolution - "puntuated equilibrium" - is different from this simplistic teaching model. What really happens is that genetic changes accumulate over very many generations but don't have much if any immediate effect on evolutionary fitness since in practice these small, incremental, personal changes are often not what drives evolution. What really drives evolution (per the inference of the fossil record) is when the *environment* (weather, food supply, disease, competitors, etc, etc) changes, often very quickly, causing accumulated genetic change to suddenly become relevant... what had previously been a benign genetic change (disease resistance or susceptibility, etc, etc) no suddenly becomes a huge change in evolutionary fitness in the new environment, and and the fate of different genetic subpopulations becomes very differnt (we see visible divergence).
This is "punctuated equlibrium" - long spans of no visible evolutionary change (equilibrium) are puntuated by brief spans of rapid visible change as accumulated genetic drift suddenly becomes relevant due to environmental change.
So... the notion of 200 generations being too quick for "natural selection to keep up" is bogus. Natural selection mosltly doesn't happen every generation - it only happens when those infrequent major environmental changes occur.
that are left. one would think that most mutations die out.
In a particulary horny make out session, Adam's 'snake' 'convinced' Eve to eat the 'fruit' of his Tree of knowledge,.. he might have mentionned something about it being good for her skin as well. This coupled with the snowballing that followed allowed the potent creative force of humanity to enter the head where it immediately started creating thoughts and the words that allowed them to be shared.
DNA is actually a record of human possibilities, possibilities radiating out from a balanced center. Like all natural structures, think bones, the only material needed is only that which responds to and/or compensates for external forces. Since expulsion from the garden(from center), mankind has been filling in the sphere of possibilities. Soon the weight of maintenance of unessential structures will fall to the way-side and what will be revealed are the 24 archetypes of human perfection, each with knowledge of good and evil over their domain. With the return of the Elohim, all unsustainable lifestyles disappear, and once again a return to the garden of eden occurs.
What ever happened to people playing with descriptions and not being trapped by them? Every single post, except for one, has been an uncertain mind wandering through someone elses description.
Don't complain about syntax, grammar, or spelling. There is no.hell like input on android.
And now if some brilliant would ask "why?", they may find instruction in the chemically-laden, drug-infested environment in which we plunge our species. We self-mutilate and, with whatever consciousness remains, marvel at how fast our species is attempting to keep up, and survive.
But asking "why?" will then present a moral conundrum. So better not ask.
Evidence that evolution has escaped you.....
"The hands that help are better far than lips that pray." - Robert Ingersoll (1833-1899)
Evolution is simply a means of responding to pressures on a population. Your argument that evolution is not occurring would be applicable by those who are anti-hunters. They always argue that hunters go after the big trophy. And while that is true, the new generations are smaller AND FASTER. In addition, they are also hiding better in the foliage. As such, this is evolution at work.
We still have loads of pressures on us. Most of it is via mental. But I suspect that there is far more evolution occuring in the rural and high density populations. The reason is that I believe that most real evolution does not occur via mutations, but via arthopod-bourne virus that are multi-species vectors and are able to bring snippets with them.
Windbourne
We pollute our environment and mindset and our generations adapt.. I bet this curve of human evolution is parrallel or otherwise relevant to our rate of advancement in technology and population..
Absent the need to interact face to face, people who make inciteful comments are no longer immediately removed from the gene pool.
Have gnu, will travel.
Evidence that evolution has escaped you.....
No, he's just one of those with a much larger load of deleterious variants.
Ezekiel 23:20
that must be preserved at all costs and colonize the galaxy, doesn't really exist. If we could send out colonists (we can't, and won't, ever), genetic variation means that in a handful of years (cosmologically speaking), the colonists wouldn't be related to us anymore. But preserving my body and life and extending it are no good. Got it.
trolololol
Millions of years of genetic variation has produced....this
My ism, it's full of beliefs.
So I think what you're saying is that, should humanity suddenly find itself in a situation where LSD is pervasive in the environment, you would actually be more fit than the rest of us, right?
Natural selection is still at work. It's always at work. What has changed is that it's now favoring a higher group intelligence. Because we now are able to correct or compensate for so many other problems with medical technology, people who would otherwise have died and been removed from the gene pool are still around and contributing.
I have terrible eyesight. If it were not for the ability of humanity to create spectacles and build cities, I'd have long ago been eaten by a large predator or fallen over something and died from the infection. We are not changing too fast for natural selection to keep up. That is natural selection at work.
LK
"Hi. This is my friend, Jack Shit, and you don't know him." - Lord Kano
http://www.imdb.com/title/tt0813715/episodes?season=1 ;-)
*kicks scientist into pit*
The G
Could it be that the moment we started valuing wisdom equal or greater to strength that we left conventional evolution in the dust and exploded forward in brain size?
They are saying there is more genetic variation. That does not equal evolution. Evolution happens when a particular gene proliferates and that only happens if the gene provides an advantage to it's host.
What this evidence might better suggest is that there are more mutagenic factors in recent history than there has been in prior history, e.g. man made chemicals in the environment and more exposure to radio active particles.
Around the time of cyrus - 200 generations ago - people first solved the problem of relative peace and prosperity over wide and fertile areas. So ever since, we are free to do most anything with no check on it but us...
I'm not sure why anybody finds this surprising. For one thing, human population is drastically larger than it was 200 generations ago. Further, genetic variations that appeared more than 200 generations (approx. 5000 years) ago are either going to be extinct or widespread for the reason that anybody who lived thousands of years ago either has no living descendants or many millions of them.
Also, most mutations probably die out quickly. You have to figure a typical genetic variant has no better chance of being reproduced than its normal copy. With an initial condition of one copy in the whole human population, the chance of it being eliminated before it spreads widely is very high. If it is a harmful mutation (by harmful I mean having an even slightly negative effect on the average number of offspring per person who has it) then it stands an even higher chance of elimination because its commonness in the population is attenuated in each generation in comparison to the more normal variants of the gene. Genetic variants that are older than 100 generations or so are likely beneficial to survival and reproduction -- at least as viable as the even older variants.
"too fast for natural selection to catch up"
Nonsense. The problem is that we've completely bypassed evolutionary mechanisms because of our obsession with preserving life at any cost, and people who ordinarily wouldn't reach reproductive age are passing on their genes.
For example: people who are obese have lower fertility rates, but thanks to fertility treatments, they can have children.
Premature-birth children are a perfect example. Even 50 years ago, they would have died. We've decided that spending $26 BILLION dollars a year on treating preemie babies is sound healthcare policy - they cost 15 times more than a normal baby to care for. We know now for a fact that the more premature a child, the poorer their development as a child and health in adulthood. Nature decided they weren't viable - but instead their genes get passed on to the next generation. It hasn't occurred to anyone that maybe it isn't such a great idea.
Same with people who have inherited diseases, things like heart defects, etc.
Each successive generation is becoming more and more dependent on medical treatments, care, drugs, etc. At some point, it'll be so obvious we can't ignore it.
Most eugenics practices are obviously immoral - but I think discontinuing an at-all-costs attitude to conception and preservation of life for babies and children would be enough.
Please help metamoderate.
Humans have overstayed heir welcome here.
All you evolutionists try to prove evolution but have not presented any solid evidence. And what it really is, you use the wrong word for what really happens. Humans progress by taking in more knowledge. Either way you look at it, a Human started as a Human and is still a Human. A monkey started as a Monkey and is still a Monkey. An idiot is still an idiot. Darwin thought that all life might be traced to a common ancestor. He imagined that the history of life on earth resembled a grand tree. Later, others believed that this “tree of life” started as a single trunk with the first simple cells. New species branched from the trunk and continued to divide into limbs, or families of plants and animals, and then into twigs, all the species within the families of plants and animals alive today. Is that really what happened? DARWIN’S TREE CHOPPED DOWN In recent years, scientists have been able to compare the genetic codes of dozens of different single-celled organisms as well as those of plants and animals. They assumed that such comparisons would confirm the branching “tree of life” proposed by Darwin. However, this has not been the case. What has the research uncovered? In 1999 biologist Malcolm S. Gordon wrote: “Life appears to have had many origins. The base of the universal tree of life appears not to have been a single root.” Is there evidence that all the major branches of life are connected to a single trunk, as Darwin believed? Gordon continues: “The traditional version of the theory of common descent apparently does not apply to kingdoms as presently recognized. It probably does not apply to many, if not all, phyla, and possibly also not to many classes within the phyla.”29 Recent research continues to contradict Darwin’s theory of common descent. For example, in 2009 an article in New Scientist magazine quoted evolutionary scientist Eric Bapteste as saying: “We have no evidence at all that the tree of life is a reality.”30 The same article quotes evolutionary biologist Michael Rose as saying: “The tree of life is being politely buried, we all know that. What’s less accepted is that our whole fundamental view of biology needs to change. Face it. Explain the complex design of your brain or your eye, or spinal cord. How about the universe? It is so precise you can pinpoint exactly where to land and when by using simple math. It is those uneducated who claim an evolution instead of the real and factual Progression of man just getting smarter by the knowledge he takes in. Facts are Facts. Only fossil evidence that was surfaced was fabricated by those uneducated men anyhow. Dave
Further explanations and studies is needed to prove this I guess!
Sadly, i can think of some 'homosapiens' who are evolving on a signifcantly slower level, despite living here on our modern Earth among civilized societies. Doubtlessly, most reading this know of whom i speak...