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Is human evolution over?

Tom Feilden | 12:03 UK time, Monday, 6 October 2008

Human evolution

What if this is as good as it gets?

Melvin Udall's wicked one liner in the film "As Good As It Gets" may have been intended to pile on the pathos for a group of depressed psychiatric patients, but the phrase works equally well as a sub-heading for Steve Jones' lecture on human evolution.

The point the celebrated geneticist and author is making is that we've reached Nirvana: If you want to know what utopia looks like, he says, just look around you. The human race has reached the point where it can step off the evolutionary treadmill.

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Advances in technology, medicine and culture mean it isn't just the fittest who get to pass their genes on to the next generation. In ancient times half our children would have died before the age of twenty. In western societies today 98% survive to the age of 21, and life expectancy is so good that even eliminating accidents and infectious disease would only raise it by another year or two. These days almost everyone gets to hand their genes on through their children.

Mutation too is slowing down as the average age at which men reproduce has fallen. Unlike women, men never rest...when it comes to making sperm. By the time the average man is 28 he's copied and pasted the original sperm - the one he got from his father - about 300 times. The figure for a fifty year old man is well over a thousand. So the fewer older fathers there are the less chance there is for random mutations to slip into the copying process and be passed on to the next generation.

The increasing ease of global travel also means that modern human populations are continually stirring and homogenising the genetic pot. While small, isolated populations can evolve quite quickly, a global gene pool acts to block evolutionary change - the future is brown.

The result is that we're no longer subject to the driving force of evolution - natural selection. We've reached stagnation.

It's a controversial view, and plenty of geneticists believe it's a mistake to try and predict future patterns in evolutionary development. Chris Stringer at the Natural History Museum points to the fate of early hominids like the neanderthals. Natural selection was driving stone age people to get bigger and stronger, but then quite suddenly, they were replaced by smaller, lighter people migrating out of Africa.

Others argue that humans are becoming less brainy and more neurotic, and still others that we're getting more brainy but less robust.

So what's the prognosis for a species that ceases to evolve? Well, presumably there's a chance that others, perhaps our closest relatives like Chimps and Gorillas might catch us up. Then again maybe the challenge to our supremacy will come from an unexpected quarter...perhaps Dolphins will inherit the earth.

Given the glacial pace of evolutionary change we probably won't have to worry about that for thousands of years. But the steady accumulation of random mutations in the gene pool does pose more of a problem. Without natural selection to winnow out the weak medical science could have its work cut out in years to come.

Then again, perhaps we'll get so smart we'll be able to repair and augment our children's DNA. Then we really will have triumphed over evolution.


Comments

  • Comment number 1.

    Worse still i think we are de-evolving.

    Natural selection does still exist, but its no longer the smartest and the fittest it favours.

    Those more likely to pass on their genes to more children are now the lazy people sitting there living off jsa. I acctually see alot of it where i live, girls as young as 13 having only one abition in life... have a baby, and then another 4 or 5 kids by the time they are 21. The problem with this ofcourse is the smarter fitter people who try to get somwhere in life tend to have less children.

    Theres a film called Idiocracy you should watch, while its a comedy, it really does summerise well the direction we are going.

    Survival of the fattest/dumbest is the way forward, good luck to the dolphins i say!

  • Comment number 2.

    If the understood mechanisms for evolution aren't working then isn't the more likely scenario that evolution itself will evolve? Nature will always find a way.

    Population density may not allow geographic isolation in the traditional sense, but as the article points out, Homo sapiens isn't bound by traditional evolutionary methodology.

    How about a mechanism where cladogenic speciation arises as a result of a self conscious decision by a group within a population to isolate themselves socially? There certainly are plenty of examples of inwardly focused social enclaves in society that might be able to develop in a manner similar to the way in which small isolated populations can evolve quite quickly.

    I have to say I'm not convinced by Prof Jones' arguments.

  • Comment number 3.

    It always annoys me when people say this. Just because you can't see something doesn't mean it's not happening. Evolution has very little to do with how long an individual survives for, it's to do with how many times they sucessfully reproduce.
    Some of the many factors acting as natural selection on human evolution:

    How much money an individual has. No it's not passed on genetically but it is socially transmitted and it does effect each individual differently, hence it's a selection process.

    How intelligent an individual is.

    The size of the social group the individual closely identifies with.etc etc.

    Just because you can't directly see evolution happening because of these things doesn't mean it's not happening. Evolution is very very slow.

  • Comment number 4.

    Mikey- The "fittest" in "survival of the fittest" has nothing to do with physical conditioning, it simply means "those most likely to rear an optimal number of offspring to adulthood."
    The higher birth rate you posit among people who are out of work is hardly a global phenomena just yet, so I don't think we've too much to worry about.

    Also, if these people are happy with the life choices they make, who are we to say they are any less intelligent than people who work 50 hour weeks making money for somebody else and/or destroying the environment? The workaholic has less time to socialise and less to spend with whatever children they do manage to produce, meaning whatever benefits you might imagine them to have naturally (and there's no proof whatsoever that there is any genetic difference between the employed and the unemployed, although I'm sure that would delight the Daily Mail) will be outweighed by the lack of nurturing these children get.

  • Comment number 5.

    The process of evolution is quite misunderstood, and often confused with natural selection.

    Natural selection is survival of the fittest through adaptation, it has been the major (but not only) driving force in the evolution for most of life.

    Indeed, natural selection in humans has slowed down in many respects, or even halted, - but not completely. Humans are still dieing of disease, malnutrition, and exposure. Two thirds of the world still live in conditions where their intrinsic biology can give them a selective advantage in reproduction and in evolution - natural selection in action. There has been no greater selective force on the human genome than famine.

    Importantly, relaxation of certain aspects of natural selection in humans has allowed other forces of selection, including social and sexual selection to act on contemporary human evolution. In an imaginary society 100 years from now where disease and poverty are abolished, these forces of selection would play an even greater role in human evolution.

    It is also important to consider that selection requires diversity as a substrate on which to act - and greater effective population size creates greater oppurtunities for diversity to arise, especially when it also involves admixture between different groups. Therefore we can expect selection to be acting differently, but in respect to rate and also in type depending on the population (defined both my current population circumstances and population history) and social stratum it occurs in.

    Finally, people must take into account that humans are the only organism that can alter their environment to suit them (instead of the other way around) - the normal principles of evolution should not be supposed to apply.

  • Comment number 6.

    I acctually see alot of it where i live, girls as young as 13 having only one abition in life... have a baby, and then another 4 or 5 kids by the time they are 21. #1

    For most of human existance life expectancy has been short; 30 years has been the upper end of life expectancy for most of humanity living without any means of understanding or controlling hygene, infection, disease and so on. Childbirth was a major cause of women`s death. Life for most also involved grindingly hard labour.

    Women would have been expected to be married and having families shortly after puberty. (In developing countries this is still the case.) Fertility decreases with age. We may simply be seeing, in western societies, a re emergence of women maturing earlier, but with a much higher life expectancy than in the past. Traditionally those that have better healthcare and education have also tended to have fewer children. In times past with high child mortality rates, having large families meant at least some children were likely to reach the stage of having their own families, and looking after their parents. Perhaps there`s a natural instinct that continues even in times of affluence?

    Has evolution stopped? The key point is timescales. A century or two is nothing; who knows what the next 100,000 years or so has in store for us?

  • Comment number 7.

    @mikey2055

    Orgel's second rule:

    "Evolution is cleverer than you are."

  • Comment number 8.

    I'd say we could evolve a bit more, but won't.

    Society acts to take away the pressures which might be conducive to evolution. (This obviously applies to the west more so than developing countries) where I believe it will still be in action and quite possibly give rise to a "fitter" human being coming out of Africa/India in eons to come (presuming we're still here...)

    Radical indeed.

    #1's is an interesting angle indeed...

  • Comment number 9.

    Evolution by 'natural selection' certainly has slowed down - perhaps to a halt in the west, but, tropical disease certainly remains a selective pressure - Malaria obviously so.

    However, as comment #2 nicely shows, we are not without the capability to isolate populations irrespective of geography, i.e. forms of sexual selection.

    Be the driving force percieved attractive trait (maybe large male muscles or long female legs), wealth, intelligence, religion...given enough time (in isolation), could produce some dramatic evolutionary possibilities.

  • Comment number 10.

    Around half of all Americans and most Muslims think that evolution never happened in the first place.

    So maybe we are getting less brainy afterall.

  • Comment number 11.

    I am not wholly convinced that this is correct.

    I believe that we are still evolving. I believe that we have all to become one colour thatnks to more access to foreign lands and much more inter-racial breeding.
    I also believe that we will become all hairless. The only reason we were covered in hair was to keep warm.
    Men from my fathers generation were less haired than his father and I in turn have less hair than my father. When I look arounf the office I note that more and more men are hairless in the arms.
    It makes sense why do we need to carry body hair today are living standards have greatly improved since day one.
    I believe we are yet to evolve to a hairless state ...BALD each and everyone of us...including women!

    To the matter of mental capacity we have not even begun to tap into that side of things yet ......This particular aspect is a huge road to travel....

    What I can't work out is where we are going and why? For what reason are we evolving?

    To summarise:

    One colour, one size and hairless. The exciting bit is the mental evolution!

  • Comment number 12.

    Chronocentrism: the wildly egocentric view that after 15 billion years or so of the Universe you (The Special One) happen to be around to witness the Pinnacle of Creation/ End of the World - I'm paraphrasing.

    Actually in this case not only are you around to *witness* the Pinnacle of Creation, you *are* the Pinnacle of Creation. A sort of God Delusion (ho ho ho).

    What will human beings look like in 1, 5, 10 million, 1 or 2 billion years time? Like Steve Jones apparently. This sounds like "The End of History" all over again. More crackpot chronocentrism we all had to contemplate.

    Humility and perspective please. I'm incoherent with rage. >:-(

  • Comment number 13.

    Has their been a generation yet that didn't believe theirs was the pinnacle, and everything afterwards would be downhill?

    Professor Jones and his supporters may as well have just said "Tsssk, young pople today. What is the world coming to?"

  • Comment number 14.

    I still believe we are in the process of evolving as a species physically but mentally the world appears to be de-evolving what with the seeming rise in ignorant fundamentalist religion seemingly on the up when in reality this should be a time of enlightenment for the human race, a time to pursue our dreams, a time to further our knowledge a time to leave the brutality of evolution behind after all is that not the gift given to us by evolution? the gift to realise evolution for the cruel being it is and giving mankind the intelligence and tools to exclude ourselves from the other species on the planet and take a step back to interpret for ourselves where we as a race are going? Unfortunately it seems that an ever-growing band of ignorant religious zealots are intent in taking us as a species back to the stone age (albeit with the mobile phone, the car, the TV etc etc) The problems in this world are manmade therefore man can solve them not god.

    Darwinism Yes
    Religion No

  • Comment number 15.

    I agree and disagree.

    The next step is designed organisms, which will be a form of reproduction accessible to the benefit of the powerful, so actually evolution will favour the most successful at gathering resources and reproducing, just as it always does.

    My wife asked me who will do all the menial work in the future, and I replied it would be humans.

  • Comment number 16.

    This Blog is hilarious.

    I dont see any proof that evolution happened in the first place.
    Where is the evidence, and dont say we are more intelligent because that is not the case. Lets face it even with all our modern tools we struggle to make any of the original seven wonders.
    I dont see anyone capable of laying out the Nazca lines these days even with modern instrumentation.

    If evolution happened where are the intermidiate steps.
    No suposed evolutionary step has added technicality to the change, they have all simplified the original. With this in mind how do you propose the complicated original sprang into action?

    Unfortunately for evolutionists you will always come back to the question of what was there before your big bang.
    The only thing that evolutionists have really seen is mutation.

    We see extinctions but we dont see any new species, only previously unknown species that have always been there just not discovered.

    To counter the "just cos you cant see it happening" arguement If evolution is happening surely at least one species would have shown development in the last 6000 years. or one species would be on the way somewhere else. Where is this happening. The answer to that is nowhere.

    Evolution isnt even a norwegian Blue, beautiful plumage, You cant even say it is no more because it didnt exist in the first place.

  • Comment number 17.

    I must say that I am very dis-appointed by the gross lack of understanding being demonstrated in this article and many of the comments that have followed it.

    Use of terms such as "de-evolving" only ever serve to mis-lead the public that evolution is some kind of directed process that leads to some kind of ultimate destination. I am very disappointed to see Steve Jones (a normally great writer) using similarly complacent rhetoric which undermines the underlying principles of modern evolutionary theory.

    The statement that we are now somehow immune to the forces of natural selection is an absurd statement that demonstrates a worrying arrogance in humanities' achievements.

    Ultimately, selective pressures will change any lineage over time as the probability of certain characteristics surviving varies. However this occurs over generations and make it almost impossible to monitor genetic shifts.

    Obnoxious comments about fatter more stupid people breeding more only serves to dehumanise other people and can lead down far darker paths (the Nazis had some very interesting ideas about human evolution that were often justified with the use of similarly sloppy observations).

  • Comment number 18.

    "What I can't work out is where we are going and why? For what reason are we evolving?"

    Karm257 - There is no long term objective, there is no why. We are not going anywhere specific for a specific reason, we just evolve and will continue evolving.

    I think that is clear the problem here is that Steve Jones cannot comprehend Human Beings evolving any further. This is of course a mistake that would have surely been made generation after generation.

    I suggest reading the "God Delusion" by Richard Dawkins to get a better (and basic)grasp of natural selection and evolution.

  • Comment number 19.

    @18

    The God delusion has more holes in it than a seive.
    It was that book more than any other that convinced me that evolution didnt happen.
    I feel sorry for Dawkins and others like him with his empty evolving life.

  • Comment number 20.

    The driving force behind evoloution is need. Where a difference gives one an advantage over another and allows them to breed more succesfully.

    Problem with humans is, whenever we encounter a problem we have evolved to the point where we can overcome it with technology. We biologically speaking dont really need to evolve to survive.

    Do i think the homosapiens will stay the same from now until enterinty? Definately not, but the way things are going i think were looking at devoloution of our species. Being intelligent and stong are no longer a real bonus, in many cases a liability.

    What does it matter anyways, im sure we will be wiped out by some sort of natural disater long before enough time as passed answere this question, so in such its a pretty meaningless debate, lol

  • Comment number 21.

    @Karm257

    I agree on the one colour and eventually similar sizes, but hairless? Body hair will maybe become finer (we still have as many folicles as chimps as far as i remember, it just gras far finer and shorter) but i cant see us losing head hair anytime soon, so long as men prefer women with hair (on their head :p)

  • Comment number 22.

    @11

    Dont you see that your end result isnt evolution but mutation down to the lowest level.
    One colour, one size, no hair. That is direct oposition to what evolutionists theory should bring about.

    In fact evolutionist theory says we all diversified from the one celled amoeba, now you are advocating that that self same process will make us all the same.

    The two processes cant exist in tandem. you cant have your cake and eat it.



  • Comment number 23.

    It has been pointed out that we no longer change to suit our changing environment, but change our environment to suit ourselves. However this does not mean the end of evolution, and there are precedents. When birds found themselves is regions with no predators and plentiful food, they did not stop evolving, they switched to largely sexual selection and we ended up with bird of paradise.

    Is this our future? Our world is not ‘red in tooth and claw’ anymore, will we select mates on their beauty and intelligence and ultimately become human birds of paradise?

  • Comment number 24.

    A number of comments point to the role of infectious disease in evolution.

    I asked Professor Jones about this before he came on the programme this morning. He acknowledged that genes conferring resistance to say AIDS or malaria would act as a powerful evolutionary driver, and suggested that, in years to come, the majority of us - like chimps - may well be equipped to shrug off the HIV infection.

    Of course that is evolution. But it's also possible that we will be clever enough to develop the drugs or vaccines to cure these diseases long before genes conferring resistance can work their way through the entire (surviving) human population.

    The point is that this ingenuity frees us from the tyranny of natural selection.

    As to whether there's a gene for laziness, or whether couch potatoes have more children, all I can say is good luck with the grant application.

  • Comment number 25.

    I can't imagine for a moment we have stopped evolving, dont they say due to a change of diet, even over a short period of time, we are taller than our Victorian ancestors, or have I misunderstood, anyway going by the interaction with technology, perhaps future generations will evolve into Darlek like creatures, A rather depressing thought is that without peneciline and medicines a large portion of humans would die out extremely quickly. If there were an immediate disaster. i.e. asteroid, Caldera volcano, a rampant virus or a return of the ice age and all modern conveniences destroyed what then, it certainly would be survival of the fittest and those perhaps geographically best placed, afterall whoever and whatever is here know obviously came through all previous catastrophys, but many also died out. Also I wonder what effect there will be on reproduction, shall I dare to say, on people who are being kept alive by modern medical methods, is that stock weaker and not so well placed to face possible harsher environments, is this what is meant by, the meak shall inherit the earth' and I'm an athiest! some of those biblical saying are good arent they?

  • Comment number 26.

    @ 19

    Please don't feel sorry for Dawkins and those who "believe" in evolution.

    My life is certainly not empty. My understanding of our (very short) place in the history of the universe, and how we exist, fills my life to a far greater extent than religion ever could.

  • Comment number 27.

    Sadly PotKettle at number 19 must be very simple, evolution is as proved as any other theory in science Richard Dawkins aside. The simple truth is that human DNA is demonstratively related to the DNA of other animals - 98% the same as chimpanzees. This is absolute clinching proof of evolution and there is no way out unless DNA doesn't exist. Intelligent Design itself is an admission of this total defeat because it is still basically based on evolution - only an evolution started by "god".

  • Comment number 28.

    I can't believe that someone can be so short-sighted and come up with an uneducated statement like that. We still don't understand for example the intricate complexities of the human genome let alone how the process of evolution works in the first place. There's a high probability that we could STILL be evolving.

    Nobody has conclusively proved or disproved that so far. After all homosapiens took approximately 2 million years to materialise from their primitive ancestors, surely a relatively short span compared to other species such as the dinosaurs that were around for a few hundred million years and spawned a myriad of sub-species to cope with different environmental factors etc

    For this guy to base his hypothesis on statements such as "Mutation too is slowing down as the average age at which men reproduce has fallen" seems to ridiculous by any standards. Hasn't this altered at varying times in our recorded and even prehistoric past due to a myriad of sociological and other factors? And if so, how would this really influence our evolution over another 2 million years? By what "barometer" has he gauged the speed of the mutation process if one so exists?

    Also what about his other statement:- "The increasing ease of global travel also means that modern human populations are continually stirring and homogenising the genetic pot. While small, isolated populations can evolve quite quickly, a global gene pool acts to block evolutionary change - the future is brown."

    Do we know this for a fact? just because there is more racial inter-breeding doesn't mean that as a race we are experiencing a period of stagnation in evolutionary terms. these could be influenced by other environmental factors. Our very climate could alter drastically in the next two hundred years due to global warming, pollution and increased CO2 emissions. Wouldn't this have severe repercussions not just f the next few hundred years but considerably longer and therefore affect our evolutionary process to an extent

    Also there is a "wildcard" here in the proverbial equation - genetic engineering. We have have evolved to the point whereby we stand on the threshold of controlling our our genetic and ultimately evolutionary destiny. Once we have fully mapped the human genome the next logical step would be the ability to alter it and therefore alter how any unborn organism will develop. The benefits are obvious: increased intelligence, longevity, a stronger immune system etc. The downside of this, is that only certain sections of human society would benefit from this due to materialism. So we could in essence have a two-tier human race - the genetic "haves" and "have-nots".

    To suggest that we have reached this so called "stagnation" point is like suggesting the world is flat

  • Comment number 29.

    In the next ten years astronomers will probably be able to detct and photograph Earth - like planets elsewhere in our galaxy. Similar, but yet possibly very different in the life that has eveolved on those worlds.
    How would humankind's evolution be influenced if those worlds were reached and colonised? It is perhaps unlikely many perfect matches for Earth would be found.
    Perhaps that is too "pie-in-the sky" for many people ( no puns intended), However,
    at the start of the 20th century it was thought reaching the Moon was impossible. Perhaps one day it will be possible to reach far - away worlds.
    So much remains to be discovered and understood, not just about ourselves, but about the Universe we inhabit, I am sure the Professor is rather too early in reaching this view.

  • Comment number 30.

    There are a great many people who seemed to fall prey to conditions that the older people shrug off - hayfever on the rise, etc. Perhaps this is the result of medical science trying to rein in death and, in turn, allow weaker or faulty genes to be passed on to the next generation.

    Sooner or later, those of a weaker constitution will lose out when resources become scarcer and scarcer. Why spend tons of resources to keep one person alive when many more could put those rare resources to better use ??

    Furthermore, this argument is truly moot because it depends heavily on the fact that we will still be stuck on Earth for all time.

    Great leaps have been made in progress to allow the colonisation of other planets in the future. What is there to prevent evolution from occurring there ??

    Larry Niven, a science fiction writer postulated tall, thin people, Belters) who live in low G environments in the asteroid belt, short, squat people from the heavy planet of Jinx, and a host of other "types"/"species" of people from different environments.

    Since he also postulated organ-legging (illegal sale of organs for transplant) long before it became fact, I tend to believe that evolving humans might have a strong possibility !!

  • Comment number 31.

    Several others have alluded to this, but I thought I would note that evolution cannot stop. Evolution is usually defined as the change in allele frequencies in a population over time, (or the change in a population's "gene pool" over time if you will). Evolution is not adaptation, adaptation is a process that contributes to evolution.

    In other words, an absence of selection doesn't mean an absence of evolution. For example, if their was no reproductive competition (i.e. no selection) so that every human being that was conceived grew up, found a mate randomly, and made two children who did the same, the human gene pool would still change with time due to chance in the process of transmitting alleles from parent to offspring.
    New mutations will still arise in this scenario and become fixed in the population. This process is known as genetic drift.

    I think natural selection is often given too much attention at the expanse of her ugly step-sisters, so-called "neutral" evolutionary processes such as genetic drift, demography, and recombination. It's a shame, because a substantial amount of the phenotypic diversity we see around us may have evolved through these processes.

    Natural selection is, of course, still shaping human genetic diversity, as shown at the lactase gene which has an allele allowing milk to be drunk into adulthood that has risen in frequency due to natural selection in Europeans and some pastoral African groups. Much selection is simply too subtle to be casually observable. The idea that medical intervention doesn't allow natural selection to remove deleterious alleles is a particularly flawed argument, with a disgusting implicit stigmatization of those with genetic disease. Human populations have greatly increased in size just as medical intervention increased. Assuming the population stays large for a while, basic population genetics theory tells us that the efficacy of selection increases with increasing population size.

    Quick final point; as for this line:
    "Without natural selection to winnow out the weak medical science could have its work cut out in years to come."
    It seems this wasn't thought out very clearly. So here is the scenario as I understand it: an allele causes a disease, and a medical breakthrough allows the diseased person to live and raise a family, thus natural selection cannot remove the allele from the population. So, assuming the same breakthrough still exists in the future, how does this pose a problem for future medical scientists?

  • Comment number 32.

    There is validity in the argument that human evolution may have slowed, as we can now intervene and prolong (reproductive) life (reproduction is the ciritical aspect), and that we can modify our environment rather than necessarily requiring adaptation. Evolutionary drive is a combination of the proactive (mutation that increases litter size will spread in a population) and reactive (to changes in the environment).
    The major evolutionary pressure currently is likely to come in the response to pathogens. Different genotypes (genetic makeup of an individual) may display different susceptibilities to a pathogen such as found in HIV infection, or malaria, or indeed the apparent susceptibilty to developing new variant CJD.
    And whilst clinical intervention is mentioned in a previous posting, Aids has been with with us for nigh on 30 years, and we have treatment, not a cure.
    There is the potential for an emerging pathogen to cut great swathes through the population, dramatically changing the human genotype. Thus selection would operate, and hence ultimately human evolution.

  • Comment number 33.

    Clarke's "childhoods end" reflects this with a race of beings - devil-like in appearance - having reached a cul-de-sac and being used as shepherds to facilitate the development of luckier species onto the next evolutionary level. Maybe instead of being the lucky ones in Clarke's book we will be the shepherds. Not to an alien race but maybe something else - AI. Afterall, natural evolution wouldn't be able to mould and program devices to a point of sophistication that may lead to sentience, but we may be able to and maybe at that point even though its not natural, it is an evolution born of natural origins and most likely would go on to create newer better versions of itself. That would surely be the crowning achievement of evolution although somewhat differing from the widespread based belief systems still portraying the human race as the pinnacle. Just a thought :)

  • Comment number 34.

    Evolution consists of two parts: variety (i.e. mutations) in the gene pool and selection (i.e. death without reproduction). What seems to be missing from your analysis is reference to any significant selection process or event.

    If for example, some people are having more kids than others, all that means is that their genes become more common in the gene pool. It doesn't mean their genes are better able to survive any particular selection event (eg a pandemic of bird-flu).

    Also, if people are having kids at a younger age, it doesn't mean that their genes are less susceptible to mutation, since the gene itself can acquire mutations over a period of thousands of years regardless of the number of generations it's been passed through.

    With modern medicine, more and more people who would have been deemed 'weak' in earlier times, are surviving to reproduce, so the gene pool is gaining more variety. International travel does homogenise the gene pool, reducing variety, but which of these effects is stronger, I don't know.

    Anyway, before anyone says evolution has "stopped", they should consider the effects of a harsh selection event (a change in environmental conditions) after which some varieties of people will adapt to the new conditions and others will not.

    Also, physical fitness is no longer the only factor determining our survival of selection events. Politics, economics, wealth, education, etc., all will play a part in determining who survives, let's say, the biggest migration in human history when sea levels rise by 20 metres. Thus; a matrix of 'fitness factors', of which genetic heritage is only one, is now at play.

    Evolution has changed but it will always exist.

  • Comment number 35.

    My understanding is that the process of evolution is

    copy, vary, select

    The selection process is the environment.

    The fittest is the best adapted to the environment it lives in. We can skew the selection process by the addition of prosthetics, e.g. glasses, hearing aids, walking sticks but the process is still continuing.

    There are example of people that are immune to HIV, that shows that the vary part is still working.

  • Comment number 36.

    Why is it that when evolution is mentioned in any article it’s always accepted that that’s how we came to be here.

    Let us not forget that “The Theory of Evolution” is just that; a theory!

  • Comment number 37.

    Evolution has not 'stopped' just moving slower. The fossil record proves that there are periods where new species evolve rapidly, a 'speciation explosion' if you like, followed by longer periods of slower evolutionary periods.

    I really can't understand why Steve jones, who is an excellent author and geneticist, would start advocating the end of human evolution. it does though create some uncofortable questions. For example:

    If evolution is stopped in developed countries, does that mean that humans in underdeveloped countries are evolving 'faster' or perhaps haven't evolved 'as much'...one can obviously see that pretty soon we are reaching a Nazi-like or Racist point of view.

    Also, what happens when survival of the fittest is translated to the genetic level as Dawkins says in 'The selfish gene'? I mean the 'brown' gene or the 'hairless' could be the fittest in certain environments but it could be close to lethal in other environments.

    Steve jones is giving a seminar on his latest theory at my university (imperial college) on the 15th of October...should be quite a debate...

  • Comment number 38.

    If we really think we are stagnating why then - lets all live within shouting distance of a nuclear power station .

  • Comment number 39.

    I'm one of those "unreasonable" types that doesn't buy into the molecules-to-man-by-random-processes evolution religion. The key postulate of said religion being that life can be derived from non-life. Evolutionists have also convinced themselves, motivated by consensus reasoning, that they are smarter than every one else. Darwinian Evolution is a religion that keeps changing its priori. Get over yourselves; the truth is that you really don't know what you're talking about. Darwinian Evolution is not science; it's just another rickety belief system.

    If "thousands of scientists" agreed you were an idiot, would you believe them?

  • Comment number 40.

    The hidden assumption in Steve Jones argument is that that the environment that we are currently doing so well (the past 8,000 years have been stable and seen the development of civilisation) is going to remain the same .
    As for the idea that there is no signifcant evolution going on how about the adaptions to diseases such as malaria (sickle cell anaemia) and to HIV .

  • Comment number 41.

    If we follow the logic of the book "Farewell to alms" by Gregory Clarks , which tries to explain why the industrial relovution started in the UK, yes , we are reaching the end of the journey in development. Since 1200 untill 1900 , the most able people in UK, which had more success in business and enterprises, had more children than the poor part of society, thus providing a large pool of clever and enterpreneurial people.
    The statistics back the argument. To day is the reverse. Brilliant people, usually college educated profesional postpone or decide not to have childs , "to keep the job". Will create problems in the future, when most kids are born from couples not able to do any useful work.

  • Comment number 42.

    41 assereto

    Are you Victorian by any chance

  • Comment number 43.

    The rate of evolution and its 'direction' are influenced by the environment. The current relative stability provided by civilization just needs a decent cataclism to kick things back into overdrive (in milennial terms).

    A brief point from your blog Tom:

    "By the time the average man is 28 he's copied and pasted the original sperm - the one he got from his father - about 300 times."

    The one he got from his father?

    Afraid that this seems to imply that (baring mutation) the son passes on the identical genetic material to his offspring as his father passed to him.

    May want to check your basic biology there. I'd suggest a quick peak at meiotic cell division for a start.

  • Comment number 44.

    Has anyone spent time measuring peoples heads , it was predicted in the 1950,s that the human head would enlarge due to watching television.

  • Comment number 45.

    I agree that modern technology has allowed Homo sapiens largely to escape from the shaping power of evolution. In the huge sweep of the Earth's history this is perhaps not very significant. There is time for us to self-destruct and a whole new evolutionary cycle to generate a host of new life forms.

    I have just published a book aimed at the general reader which examines Homo sapiens as just another ape species. It is called THE APES THAT SING THEIR SOULS. I summarise human evolution and look at many of our behaviours to show they are programmed by our animal nature. I make a link between this scientific understanding with inner experience expressed in the arts and scriptures. For example love is an inner experience but also a hormonal event.

    I would be delighted to post more information to anyone interested.

 

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