Human Genes Still Evolving 810
MediumFormat writes "The New York Times is running an article that discusses the continuing evolution of human genes. From the article: 'The genes that show this evolutionary change include some responsible for the senses of taste and smell, digestion, bone structure, skin color and brain function.' Darwin Awards aside, what made people think that evolution stopped with the modern era?"
Civilisation vs Evolution (Score:5, Interesting)
Interesting, but (Score:4, Interesting)
A number of things have changed that will greatly impact our evolution that hasn't been experienced by our species before:
1. Ease of migration allowing for extreme mixing of previously separated social groups (this has been in decline over the last few thousand years, but now that you can travel between continents relatively quickly and cheaply, the impact will be much much greater.)
2. Knowingly allowing, accepting, and encouraging reproduction of individuals, who...shouldn't (No, I don't mean Bush). There's some bad genes out there. Some that shouldn't be passed on. While we're at a point where we can curtail some of this through prescreening parents for likely inherited traits, we continue to become more accepting of people with, well, bad genes. Aren't we effectively letting people piss into the pool?
3. Will this spawn a new race (as in car) by parents to "maximize" the brain genes described in TFA? Do I have to listen to soccer mom's brag about their kids DNA now?
4. How will this impact governments? And more importantly, dating websites?
I guess only time will tell.
Re:DID people actually think evolution had stopped (Score:3, Interesting)
If we want to preferentialy breed inteligence into future generations we're going to have to do it intentionaly, either by a direct process of eugenics (possibly by giving financial benefits to inteligent people who have children and heavily taxing less inteligent people who do ... which runs into the problem of how you measure inteligence reliably) or by human genettic engineering.
One interesting possibility would be to have everybody sterilised with reproductive material kept on ice, and then when a woman wants to have children give her artificial insemination with an embryo who's biological parents are of "aproved stock". Yeah, somewhat abusable by whomever has control over the system - not to mention the unfortuante problem of monoculture if enough genetic diversity doesn't get into teh next generation as a result.
pretty obvious (Score:4, Interesting)
In fact, natural selection has clearly operated at a huge scale, when Europeans settled every corner of the globe, while indiginous populations have disappeared or mingled. Genes associated with those Europeans have spread, while many others have nearly disappeared.
This is an example of group selection, and it has selected many genes at once; some of them may have helped Europeans in their conquests, others may have just been along for the ride.
On the flipside, medical and environmental advances probably are causing us to lose functions at a massive rate: no need to deal with food-born pathogens if you don't encounter any.
Evolution isn't as neat and simple as "better mammal wins" or "better gene gets selected".
The Chinese are illustrative of another interesting development in evolution: limiting population growth in the absence of high child mortality and in the presence of modern medical technologies and genetic testing. Whatever policies nations adopt in that environment, they'll end up acting as "natural" selection as well.
Re:Civilisation vs Evolution (Score:5, Interesting)
This provides a criterion, notwithstanding that it is subjective, whereby you can say that the third-world ones are "superior"
Obligatory Women's Day comment (Score:2, Interesting)
Now I know this is a short-term perspective, but who knows how long this will go on - look at women these days (and for the last century). If women want to work and have a career, then they'd do well to be smart enough not to have children. So essentially, modern society removes a good deal of good genes from the gene pool. Female academics have much fewer children, they're pickier about who they marry/have those children with. And there's very little sign that this is going to ease up anytime soon It's much easier for you guys - when you're an academic and successful, picking up a woman isn't that hard, so you'll get to pass on your genes. Just watch out you don't have daughters, because if they inherit your intelligence, your genes may be in a dead end there.
The End of Evolution? (Score:1, Interesting)
Probably the fact that, for most of human history, being 'poor' meant starving to death and begetting no kin, whereas now, in some countries at least, it means being more likely to become obese and begetting more kin (in the sense that poorer people tend to have more children than richer people: it's one of the main mechanisms by which social inequalities maintain themselves).
That means that, at a crude level, natural selection has ceased to be for most of the human race. (An exception might be Southern Africa and AIDS: It's more likely many people will develop AIDS immunities there than anywhere else, but it might still take hundreds of years for that to happen: Evolution isn't nice or pretty in any way - it's about widespread and systematic death and destruction for periods of time often lasting much longer than the whole of human recorded history - the 'end' of evolution is generally a good thing as far as human wellbeing is concerned)
The issue of 'cultural evolution' is more complicated and ambiguous, however, and - if it exists in any meaningful sense - is probably still 'alive'.
Re:Natural selection is not just survival. (Score:5, Interesting)
Precisely. And yet Newton undoubtedly had an effect on the general society around him, not least through his work in the mint. The overall population benefited from his labours, although he never himself returned his genes to the general pool.
Lets say, as is generally thought, that Newton had genes which gave him an extreme "geek" factor. This factor benefits the general populace, although the "geek" genes themselves may never be passed on directly. However, the potential for such genes to be expressed is passed on through, for example, Newton's siblings and close relatives.
Evolution works on a macro population level, not just on an individual organisim by organism basis.
Re:Cost of living (Score:3, Interesting)
With genetically engineered plants, this may stop being true. It's not uncommon for such plants to be modified to produce sterile seeds [banterminator.org]. The idea is, of course, that farmers will have to buy their next seed from the producer as well. Of course this means that if you can't get new seeds from such a company (maybe because those companies all died due toeconomy collapse), and if the farmer doesn't happen to have traditional seed around (which is likely if GM food gets the norm), then the farmer will not be able to produce food anymore, neither for himself, nor for anyone else.
Ok, this could also be seen as an evolutionary force: Those who don't use such plants will have an evolutionary advantage. Most interestingly, many of them will, again, most probably be poorer farmers who just cannot afford to buy the GM seed.
Why evolution in humans should have stopped by now (Score:3, Interesting)
Darwin Awards aside, what made people think that evolution stopped with the modern era?
The fact that through medical care and technology, we have almost eliminated "survival of the fittest" (better written as "survival of the best fit to their habitat")?
People now live and have children when they would previously have died, either through diseases, or harsh environmental conditions. The elimination of the process of natural selection should see to it that evolution in humans no longer occurs, at least not in any beneficial way. Bad genes that lead to people having chronic medical conditions are not removed from the gene pool by those people dying without producing offspring. Humankind needs to step in with more advanced medical care and gene therapy to replace what was once done by nature.
Just my $0.02 of course!
The next big evolutionary step.... (Score:5, Interesting)
Will the next big evolutionary change be (partial?) resistance to Bird-flu or Ebola ?
Re:Still going strong (Score:5, Interesting)
http://www.timesonline.co.uk/article/0,,2087-2058
"According to the study, north European women evolved blonde hair and blue eyes at the end of the Ice Age to make them stand out from their rivals at a time of fierce competition for scarce males."
Re:Still going strong (Score:1, Interesting)
(note: I'm not a racist nor do I propose that we should do anything to stop these things that I'm about to describe from happening)
Example: a couple is infertile, they get their seeds artificially implanted, this way passing on their genetic make up. So now they have _possibly_ passed on the genetic factors that caused their infertility to the next generation which will then again pass it on because being able to reproduce is no longer a factor. In a long timescale this might lead to most people being unable to reproduce without aid.
Example: some scientist/business man/whatever has genes in him that make him brilliant at what he does. This however does not lead him to having many children. He will probably instead consentrate on his carreer and use birth control with his beatifull genetically magnificent wife.
Example: a violent drug using scumback is unenployed all his life, not because he's poor but because he's lazy and completely unskilled at anything. Despite all this he can reproduce, possibly with several women, and have many children who might not be pathetic like their father (one of them might be a scientist described in example 1) but still contain the same unbeneficial genes.
Ofcourse by the time every human being on earth is an infertile mindless slob I'll be long dead and really couldn't care less if the whole race is wiped out after I'm gone, but this is why people say that evolutionary mechanisms no longer work. I think.
Re:Weak and strong are cultural. (Score:5, Interesting)
But what's in the DNA doesn't correlate particularly well with what we have culturally labelled 'races'. The genetic difference between a European, an Arab, an Indian, a Chinaman, an aboriginal, and a native American isn't all that much, compared to the genetic difference between African tribe A and African tribe B. And yet we consider David Smith and Tanaka Jiro to be of different 'races', while two Africans of far greater genetic diversity from each other we lump together as 'black'.
Re:Cost of living (Score:3, Interesting)
Maybe, depending on how things go, even likely. That said, we have seen economic and social collapse without this happening (see the end of the former soviet union for a nice example)
Regardless, you are right that a hunter-gatherer has an even better chance, but that is only in line with the argument I was trying to make.
Less dependence on society + technology == better chance on survival when society collapses.
Re:bleh, bone structure. (Score:4, Interesting)
First link [prb.org]I found on the subject via google.
basis of evolution (Score:3, Interesting)
The problem evolution is having now is that in order for the primary mechanism of evolution to "work", a significant portion of the members of a population have to die. (not survive long enough to reproduce) In today's modern human socity, life is valued and society helps people to survive that without help would not have made it.
Some of the most extreme examples include people that have a genetic defect that would normally be fatal, but due to modern medical technology they are able to go on living. They have children, some of which inherit those different genes and also suffer from the same genetic condition. 500 years ago this would not have happened because the original defect would have been "weeded out of the gene pool" and there would have been no children with the same defect.
Evolution may still be occurring, but it is very likely going a lot slower than it was even a decade ago. It's also likely working a little different now than it did in the past - the other functional feature of evolution is natural selection, and the random attributes that people find attractive in finding a partner have probably changed over time and this also would affect evoltion - I'd expect this to now be the dominent influence on human evolution.
Genes and natural selection. (Score:5, Interesting)
Random mutations have to encode for a new protein that activates in the right cells and "does the right thing". From then on, this is likely to become a "gene": Almost any random mutation will invalidate the protein, and disable the "feature".
Suppose such a new "invention" is not always advantageous. Say, only during an ice age. During ice ages, those carrying the intact encoding for the protein (we say they "have the gene"), will survive best, those that don't have it will drop in numbers. Once such a condition is over (say ice age stops), natural selection suddely starts to favor those that "do not have the gene". Still, as they decend from a population where most had the gene to survive, they remain "genetically close", and the gene will easily activate and proliferate during the next ice age.
A real world example is Sicle Cell Anemia. It is a genetic disease: You're born with or without it. Advantage of HAVING the disease? You don't die of Malaria (you do die of the disease, but most have had children by then).
So depending on the amount of malaria mosquitos around, the percentage of people with the Sicle Cell Anemia gene varies a lot. Natural selection at work!
Now, if you look at 10000 to 15000 years, it is unlikely that "evolution" has "invented" a lot of new genes. That however genes have activated and deactivated is however very likely.
If the "running fast" gene was "mostly essential" 10000 years ago in africa, but now not any more, then natural selection would have ensured that 90-95% of the population had that gene 10000 years ago. Nowadays, there is no longer a selection for-or-against this gene. So, the percentage of the people having the gene will slowly drop (I don't work in the field, I have no idea how fast this goes).
Did you ever notice that different children "don't like" different foods? This is a genetic safeguard to preserve the species. Evolution apparently "invented" that a long time ago.
If five percent of your tribe "Simply doesn't like to eat chicken", and the H5N1 Chicken flue comes around, about 5% of the tribe is likely to survive to pass on a much elevated "don't like chicken" gene.
Most likely the "common knowledge" about what to eat and what not to eat has leveled out the "taste" genes: They no longer significantly influence survival.
Re:Genes are evolving, population is not (Score:3, Interesting)
Anyway, there are factors that tend to counter overpopulation, such as transmittable diseases (our population is their environment), and a population that is growing faster than it's food supply, so over-population (in any evolutionarily meaningful sense) can only ever be a temporary phenomenon - it's self correcting.
Of course we are, and faster than many assume! (Score:2, Interesting)
1) the evolving american: One very interesting and MEASURABLE transition in human genome has occurred right here in america, and in a geological/evolutionary blink of an eye... Our tallness (no, not fatness)
Some above have said that, 'well sure evolution exists, but it is purely accidental and could never adjust for overpopulation, etc'
2) the swimming primate: Has anyone noticed, that of all the primates in existance, humans are the best adapted to swimming? How many other primates concentrate their populations on shorelines? How many can swim at all? From what I hear, very few... As one who has faith in our internal programmings, I am very curious where we are headed and why...
Re:bad things (Score:3, Interesting)
It is a bad thing. We've lost the filter aspect of evolution. Sure, the genes are changing, but it's no longer survival of the fittest. Say 100 years ago disease X killed all carriers of the defective gene before they could breed. With modern medicine, they can live a full life. The side-effect is that if they then have children, the defective gene gets passed down. Given enough generations, every one will be carrying it eventually. This doesn't count for fatal diseases, for example I believe that in 100 years or so everyone will have poor eyesight. It's so easy to rectify, so the poorly-sighted hunter/gatherers no longer go hungry.
What's the solution? Give up medicine all together? Cull the weak? Ban genenicly deficient people from having children? Somehow, everything that might solve this is infinately worse than the problem itself. I guess we'll just need to get used to depending on medicine as a race in order to continue.
Re:bleh, bone structure. (Score:3, Interesting)
Oftentimes people say "intelligent" when what they really mean is "educated".
I could be wrong, but I kinda think that this is one of those times.
Also, it does appear to be a very strong human instinct to have more babies when times are though. When you feel that your kids will have a lesser chance of survival, you go into the numbers game. A very sound survival strategy, IMO.
Re:Evolution and Jerry Springer (Score:2, Interesting)
Who is to say that humans as a species is simply one of those dead end freakish lines that will end abruptly while more long standing lines dont end up as the dominant species? there are many more lines of species on this planet that were here long before us.
We are simply a accidential branch that will collapse and the earth will go on.
Jerry springer is my PROOF of that hypothesis.
I LIKE my pinkies! (Score:3, Interesting)
I sure [coinmanipulation.com] hope [pentrix.com] not [bennygoodman.com]!
Re:VERY SLOW ... (Score:2, Interesting)
What made people think evolution stopped? (Score:3, Interesting)
Still it's good to have actual data to back up the reasonable assumption that evolution hasn't stopped since we see nothing that would have stopped it. (Tools again!) We get a kick out of scientists breathlessly announcing things that "everybody knows", but there's a long and growing list of things "everybody knew" that turned out to be wrong. When studying the obvious, occasionally you find useful things that nobody saw, because the truth was so "obvious".
Re:Less intelligent (Score:5, Interesting)
Racial biology has been proven a pseudo-science for quite some time
These beliefs are the exact kind of "politically correct" thinking that holds back research in the area of human intelligence. People are so adverse to labeling each other that they ignore real research that hopes to expand our knowledge of human intelligence. How can we possibly think that different human races could evolve to look so different but did not evolve differently at all internally?
The studies that the GP post mentioned are very, VERY numerous; but I will mention one here. A study done by the University of the Witwatersrand (a liberal college in South Africa) tested hundreds of students using Raven's Matrices. Raven's Matrices are the best known and most researched culturally-reduced tests that we have for rating IQ. They use diagrammatic puzzles with a missing part. You could hardly argue that any level of college education could help you find the missing peice of a puzzle.
It is documented that Sub-Saharan Africans have an average IQ of about 70. African university students scored an average of 84 on these tests, which is about 15 points higher than average which is the same as it is in America and Europe. Highly selected engineering students with extensive training in math and science scored about 103. This is also similar to Europe and America, where engineering students in college generally have IQs of about 15 points higher than liberal arts majors. This doesnt mean that their more intense schooling made them smarter, just that they generally must be smarter to even attempt a more intellectually intense career.
People think of sub-70 scores on an IQ test to mean mental retardation. That is only because among caucasions, people with such low IQ scores generally are retarded as a result of in utero complications. They also often have visible deficiencies in motor skills and speech. Sub-70 IQ South Africans are often technically normal, because that is not a very low score for them.
Thinking of it in terms of mental age, an adult with an IQ of 70 has the mental age of an 11 year old. I could drive, work on the farm, and shoot a gun before the age of 11. Having an IQ of 70 does not make you retarded, it is just that there is a strong correlation in America that people with low IQ are also retarded.
All of this culturally biased nonsense is just that: nonsense. Early IQ test were definetly culturally biased, but that has been fixed for the most part. Asians generally score better on American IQ tests than Americans do, so how could they possibly be culturally biased? And many tests, such as Raven's Progressive Matrices, have nothing to do with education level either.
You cannot fix a problem until you accept that it exists.
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Re:Have you ever considered... (Score:3, Interesting)
Sooner or later the social health system fails - which is actually already forseeable in most european countries. It worked for about 2 generation and I give them maybe one more generation, maybe 2, tops.
Re:Original paper (Score:2, Interesting)
Re:Worse Yet - Arspergers Syndrom (Score:3, Interesting)
Quite possible. Considering that brains are sort of our specialty as a species, we tend to think that smart is good. But as far as natural selection is concerned, we may just need to be smart enough. It could be that excessively intelligent people are more likely to get distracted into activities that compete with their real business (evolutionarily speaking) of spreading their genes as widely as possible.
Re:Less intelligent (Score:3, Interesting)
The brain is a complex organism. There are definite genetic variations in brain organization - see V. S. Ramachandran's Reith Lectures [bbc.co.uk] for some examples. Some of these may well make certain individuals better able to sit all day at a computer terminal doing programming than others who have difficultly mustering the sustained attention to logical detail necessary for this particular task.
This doesn't make one group "better" than the other. It makes each group better at different things. The really difficult moral question arises if we come to know that certain individuals are genetically less well suited for the sorts of occupations most needed in a modern economy. What does a society do about those people who would have been perfectly good factory workers, but rather poor information workers, when there is no longer much demand for factory workers? Do we just let the devil take the hindmost as we seem to be doing now?
From one of those South African white guys (Score:3, Interesting)