back to article Global warming COULD SHRINK THE HUMAN RACE

Modern mammals, including humans, could be at risk of shrinking as a result of global warming, just as teeny prehistoric horses shrank to an even smaller size when temperatures rose 56 million years ago. Modern Morgan horse (left) thinks about eating teeny Sifrhippus (right) Modern Morgan horse (left) thinks about eating …


This topic is closed for new posts.
  1. g e

    It's already happened

    Go to Willenhall, Coventry. Everyone's about 5 foot tall.

    1. This post has been deleted by its author

      1. Anonymous Coward
        Anonymous Coward

        Re: Re: It's already happened

        They eat greasy feet? What is this, a remake of The Hills Have Pies?

      2. Morphius

        Re: Re: It's already happened

        I had heard that Coventry was odd, but this statement just takes the biscuit... "Something about a diet of greasy feet..."

    2. Anonymous Coward
      Anonymous Coward

      Re: It's already happened

      Or Hillfields. Or wood end. I think its more the general state of Coventry than anything evolutionary. Something about a diet of greasy food, cheap super strength larger and knocked off fags.

      1. g e

        Re: Re: It's already happened

        I didn't want to stereotype the good burgers (sic, snigger) of Cov and hoped to give them an excuse for their diminutive stature via the Church of Climatology.

        However my thinly veiled ruse has been uncovered and the truth duly outed!


        1. fixit_f
          Thumb Up

          Re: Re: Re: It's already happened

          Rubbish - I'm from the Coventry area and I'm 6'2"

          Agree that Coventry is an absolute bloody armpit of a town though.

  2. Ogi

    I'm not sure about this...

    I mean, some of the tallest people I know are from some of the hottest climes, particularly Africa. I always thought being larger helps in hot climates due to increased surface area for cooling.

    Also, humans seem to be getting taller with time, statistically speaking. I believe the average height in the UK has been increasing for centuries now ( I cannot for the life of me remember where the status for this came from, but I do remember reading about it).

    Then again, they are talking size in weight. I can imagine humans getting lighter, as they need less fat to keep warm, etc... Those Africans I mentioned were tall, but very lean.

    Interesting study, none the less.

    1. DrXym Silver badge

      Re: I'm not sure about this...

      "I always thought being larger helps in hot climates due to increased surface area for cooling."

      It's the opposite. As you increase it's harder to lose heat because your volume to surface area increases. That's why small animals tend to have faster metabolisms.

    2. foo_bar_baz

      My thoughts exactly

      "It's not the first time that scientists have noticed that mammals seem to be smaller in hotter climates, and have speculated that evolution takes care of this, because smaller animals will thrive in high temperatures because their bodies are easier to cool."

      What? Have these people ever been to Africa and Asia? Tigers, lions and leopards vs. lynx? Eland are bigger than moose. African buffalo aren't smaller than bison or wisent. Not to mention elephants, giraffes, etc.

      Temperature might have an effect on size, but surely other things like availability of food and other evolutionary quirks like elephants' ears.

      1. This post has been deleted by its author

    3. Loyal Commenter Silver badge

      Re: I'm not sure about this...

      Taller, yes, but the number that counts is not height, but volume. I'd give you good odds that there is an evolutionary pressure for some African peoples being tall (I thinking places like Kenya and Ethiopia here), and that this pressure is probably related to why they make some of the world's best long distance runners. I'd also give good odds that whilst tall, their body volume is considerably lower than shorter people hailing from cooler climates.

    4. James Micallef Silver badge

      Re: I'm not sure about this...

      Yes, but the east africans are tall and skinny, that gives them larger surface area-to-body mass ratio, which helps with cooling. People evolved in cold climates like scandinavian vikings are giant beefy f**kers in all dimensions, hence low ratio of surface area to body mass allowing them to stay cool.

      This won't really affect humans that much (or domestic and 'indoor' farm anilmals) seeing the extensive use of heating / air conditioning, but it would affect wild animals. It's likely that few animals will be able to adjust their range by moving north/south to find a more optimal temperature because they'll find humans in the way.

    5. Native Angeleno

      Re: I'm not sure about this

      Bulletin, healthy adult humans even today range in size from just under 4 feet to about double that. Their size doesn't depend on whether they got much more or much less sun or water due to their local climate. It does depend, tho, on the level of nutrition they receive while they're growing and whether their genes support potential growth beyond a certain height. Within two generations, humans in general can eat differently and therefore grow to different sizes than their parents and grandparents. And do! Just look around! The idea the entire species would permanently shrink would have to mean their larger sizes would not allow them to live beyond puberty, and the smaller size would. That wouldn't be due necessarily to climate change, as it could have been over a period of many centuries with horses, but would require some kind of mass death of all prepubescents above a certain height. There would necessitate a bizarre change in the environment that would benefit a smaller size. Climate change could not account for that. So the implication in this POORLY written article, by someone who really has little clue to how evolution works, that rising or falling temps would necessarily kill off all tall prepubescants worldwide and benefit much smaller prepubescants, is too preposterous to figure out what kind of condtions could actually cause that.

      If there's no protein around, a generation of 6 1/2 ft parents could see their kids grow to 5 ft and no more. Climate change does not imply any such condition. A world of exploding volcanoes would kill off most, and the rest would remain tall IF they had the protein to continue to eat. The conditions of what it would take to shrink human size universally is beyond the understanding of the "author" of this piece. I AM sure about this.


    6. Native Angeleno

      Re: I'm not sure about this...

      The tall Africans drink cow's blood. It's the protein that makes them tall, despite the temps. The entire article is junk. Climate change is real---400 billion tons of ice melt each day at the poles---but the not-so-bright idea the entire species could shrink due to climate change is really dumb, unless all protein disappeared, and the climate that would kill off all protein would kill us off too (we're protein!).

      1. John Brookes

        Re: Re: I'm not sure about this

        As a wise friend once said to me, "Just because you are sure, doesn't mean you're right"

        It doesn't imply any such mass wipeout of tall people: that *would* be a nonsense. What it means is that over many generations, taller people would be less likely to reproduce, leading to a gradual reduction in the average size of members of the species. Obviously,

        How might this come to pass? Well, given the self-evident tendency of surface area per unit volume to decrease with increasing volume, larger animals find it more difficult to remain cool if the temperature increases - not impossible, just more difficult.

        That implies less activity for larger animals, since activity produces heat that - unless removed - might cause dehydration/heatstroke/.... Less activity implies a reduced ability to support a family than a smaller but otherwise identical animal (less foraging time, smaller hunting range, or ...). Smaller families for (genetically) larger members of a species leads to a gradual diminution of the average size of a species as a whole.

        Doesn't sound too implausible to me.

      2. 0_Flybert_0

        Re: Re: I'm not sure about this @ Native

        if food .. water .. fuel or other resources got short ..

        .. suspect the tall, strong and violent *might is right* people would prevail over the smaller among us .. and isn't that today the way it works in most of the world ?

        in agreement


    7. gmciver

      Re: I'm not sure about this...

      Yes, taller because they have longer legs usually. Short legs (like Europeans') are a cold weather adaptation. Long legs lose heat quicker. House sparrows were introduced with European settlers to North America and now now the further south you go in the USA, the longer their legs.

      This article is rubbish as far as any human implications go. The timescale is too short to have any effect on human evolution and countervailing trends (not the least sexual selection by women of taller men) put pressure in the other direction.

  3. Lord of Cheese

    Another study tenuously linked to CAGW (for the purposes of funding no doubt).

    Global warming, is there anything it cant do? For the complete and growing list see

    1. Andrew Orlowski (Written by Reg staff)


      I tried to get John Brignell in to do staff training about using statistics. His was in particularly poor health and it didn't happen.

      I wish I'd tried harder.

  4. Anonymous Coward
    Anonymous Coward

    Totally missing the point paraphrase time!

    "Global warming creates My Little Pony"

    1. Lupus

      Re: Totally missing the point paraphrase time!

      I wonder who'll end up getting the contracts for defending against the Sonic Rainboom...

  5. Chris Miller

    I thought Stephen Jay Gould had debunked this

    Read Chapter 5 of "Life's Grandeur" for the fascinating complexity of equine evolution. To vastly oversimplify - the traditional story (developed by TH Huxley) of small many-toed horses evolving linearly via larger specimens with fewer toes up to modern Clydesdales is erroneous. At any given point in time and space there were many different species of equus trotting around - some smaller, some larger; some with fewer toes, some with more - it's just that the surviving examples we find today are of the larger, single-toed variety (and the earliest ones were the opposite).

    It may be that warmer climates drove selection of smaller animals, and vice versa, but this would not have been a simple linear process.

  6. Anonymous Coward
    Anonymous Coward

    And we'd be healthier !

    Shorter => lower Body Mass Index ;-)

    1. Anonymous Coward
      Anonymous Coward

      Re: And we'd be healthier !

      Taller would lower Body mass index not shorter. weight (kg) / height (m squared)

      1. Aaron Em

        Re: Re: And we'd be healthier !

        Height in meters squared? Did you forget you've left your usual four-dimensional universe for Flatland?

  7. Fat Northerner

    Will never happen.

    Unlike all other animals, we've conquered the environment with intelligence, so physical characteristics are irrelevant.

    However we carry over our evolution so birds fancy tall blokes, the tendency is for increase in height. World war two and the welfare state has caused the massive increase in height over the last century, and I see no reason to see it end.

    Firstly the war meant that all the dutch are tall because half the dutch women were screwing the same giant of a german soldier, if you're going to fall on your back with your legs in the air for an occupying force, it might as well be for a tall one. The same is true for all the HausFraus in the 50s, with the yanks.

    Secondly, the welfare state allows women to screw whoever the want and not worry about how they're fed.

    Hey presto, any society where you've conquered the environment and women have a choice, will ensure increasing physical attractiveness. (and intelligence, because stupid men can't get laid, because they're poor.)

    1. Graham Bartlett

      Re: Will never happen.

      Not sure it guarantees intelligence. If you guarantee the survival of all sprogs, then thick chav slappers (of both sexes) who get too pissed to use a rubber are going to out-sprog intelligent couples who take a more planned approach. And thick ultra-religious nutters who believe you're destined for hell if you use contraception are also going to out-sprog intelligent people.

      1. Loyal Commenter Silver badge

        Re: Re: Will never happen.

        ...And then the food supply will fail because they will replace the watering system with one that uses a 'sports energy drink' because it has 'electrolytes'...

    2. Armando 123

      Re: Will never happen.

      One niggle, I'd say it's more to do with the food production capacity (and the ability to move it around the globe) rather than the welfare state, but you make good points.

    3. Anonymous Coward
      Anonymous Coward

      Re: Will never happen.

      A little overgeneralistic, but I would also add I've noticed a correlation between facial beauty and breast size in women. A beautiful woman doesn't need big jugs to attract a mate, though it helps!

      However, it remains to be seen whether 'conquering the environment' is an intelligent thing to do - it in no way guarantees long-term survival. Pity none of us will be around to observe the consequences.

      Our "intelligence" has caused a population explosion, environmental imbalance and host stress that most viruses would envy.

  8. Evil Auditor Silver badge

    Interesting article

    However, "However, the potentially rapid nature of climate change now could mean that evolution doesn't have time to work its magic, so the handy planet-saving, human-rescuing shrinking doesn't get a chance to get going." sounds like a load of speculative dung.

  9. Lloyd

    Didn't the Dead Kennedys write a song about this?

    Well, kinda.

  10. John Hawkins

    Bergmann's rule

    Ah well, nothing new here folks - Christian Bergmann noted back in 1847 that mammals tended to be smaller in warmer climates than than individuals of the same species in cooler climates:

    "Über die Verhältnisse der Wärmeökonomie der Thiere zu ihrer Grösse".

    This is in the long term and as the saying goes, in the long term we are all dead so the correct response here would be 'meh'.

  11. Anonymous Coward
    Anonymous Coward


    I think someone omitted to tell the dinosaurs that they had to shrink during warm weather!

    1. Anonymous Coward
      Anonymous Coward

      Re: Er

      Dinosaurs are not warm-blooded mammals. Being bigger helped them retain heat and start eating earlier in the morning..

  12. AndrueC Silver badge

    Unlike horses, we have invented air conditioning.

  13. Anonymous John

    Re "You can either adapt, or you go extinct"

    Or you can make your environment adapt to you. Something we have been doing for thousands of years now.

    1. Michael M

      Re: Re "You can either adapt, or you go extinct"

      If there was a competition for 'Last Species Standing' we would probably win our Mammal class. Hurrah for us.

      1. Allan George Dyer Silver badge

        Re: Re: Re "You can either adapt, or you go extinct"

        Nah, I'd bet on the rats, and with fools like you betting the other way, I'll get good odds. I'll be rolling in it when we're all dead. Just pile the dosh in my coffin.

  14. Mako

    "Here's some Benylin."

    "Thanks but...I didn't ask for any cough mixture."

    "I thought you said you w..."

    "No, I said I was feeling a little horse!"

    I thank yow.

  15. Anonymous Coward
    Anonymous Coward


    Yeah! cause we all know the girls dig those shorter, smaller, wimpier guys. They won't be able to resist when they take their tops off, during those future, globally warmed, long hot summers.

    1. Anonymous Coward
      Anonymous Coward

      Re: Global warming COULD SHRINK THE HUMAN RACE

      Napoleon did alright for himself...

      1. JetSetJim Silver badge

        Re: Re: Global warming COULD SHRINK THE HUMAN RACE

        Napoleon was 5'6", about average for the time.

        The "small man - big ego" theory is a bit of a myth

  16. Loyal Commenter Silver badge

    It's all to do with surface-area to volume ratios

    Warm blooded animals need to lose heat to the environment at a controlled rate. Two factors govern the rate of heat loss - the temperature difference between environment and body, and the body's surface area to volume ratio.

    As the temperature of the environment increases, the heat loss decreases, as the rate of heat flow is proportional to the temperature difference - in other words if the environment is ten degrees cooler than you, you lose heat twice as fast than if it is only five degrees cooler. If the environment is hotter than you, you're in trouble.

    The body generates heat at a rate that is proportional to the volume, in other words an animal twice the size will produce twice as much heat. However, the heat loss is through the body's surface, and doubling the volume of an animal does not double the surface area. This is why large animals tend to have wrinkly skin, to increase the surface area, and also why elephants have big ears (nothing to do with Noddy not paying the ransom).

    In short, bigger animals lose heat slower than smaller ones, so in a warmer environment, there is a selective pressure for animals to become smaller to lose heat faster.

    1. Anonymous Coward

      Re: It's all to do with surface-area to volume ratios

      Really ?

      It's pretty bloody hot on the plains of the Serengeti but elephants are quite big aren't they ?

      Anyone considered an alternative hypothesis where there may have been a food shortage thus a smaller body requires less calories.

      1. Loyal Commenter Silver badge

        Re: Re: It's all to do with surface-area to volume ratios

        As noted, elephants have lots of very wrinkled skin, and massive ears to increase their heat loss. They also have a slower metabolism than smaller creatures, and a fondness for seeking water to cool down in.

  17. Anonymous Coward

    Utter Testicles

    When the dinosaurs walked the earth it was a lot hotter than it is now. Who is giving this moron a research grant, Mystic Meg ?

    In Australia statistics show when ice cream sales go up when there are more shark attacks !

    1. frank ly Silver badge

      Re: Utter Testicles

      Maybe the human metabolism breaks down vanilla and/or milk products so that some is exuded via the sweat glands and acts as a shark-attractant? This needs some controlled experiments and careful observation. Can I have a grant please?

    2. Loyal Commenter Silver badge

      Re: Utter Testicles

      You might have missed the somewhat salient fact that dinosaurs are cold-blooded, not warm blooded. Mammals at the time were tiny rodent-like things.

      1. Evil Auditor Silver badge

        Re: Re: Utter Testicles

        You might have missed the somewhat salient fact that dinosaurs are extinct, i.e. were cold-blooded - there's a grammar nazi when you needn't one

        1. Anonymous Coward
          Anonymous Coward

          Re: Re: Re: Utter Testicles

          What's your day job Evil Auditor ?

          What ever it is, stick to it as your not going to be able to feed your family if you take up a comedy career.

        2. Loyal Commenter Silver badge

          @Evil Auditor

          Birds are dinosaurs. Discuss.

      2. Anonymous Coward

        Re: Re: Utter Testicles

        I'll repeat this as you obviously missed it:

        Elephants are large and the Serengeti is damn hot.

        I've never seen a camel the size of a chihuahua and it gets over 50 celsius in the Sahara.

        These are both mammals the last time I looked or has taxonomy taken some weird twist and classified them as cephalopoda while I was holidaying on the Moon ?

        This paper deserves star billing on as it's complete and utter crap.

        1. Loyal Commenter Silver badge

          Re: Re: Re: Utter Testicles

          To respond to your two points:

          Elephants, and other large animals living in a similar environment have specific adaptions to cope with the need for increased heat loss - in the case of elephants and rhinoceroses, these are large skin surface area, increasing the surface area to volume ratio, and a propensity to seek water to cool down in - direct heat conduction through water is much more efficient than through air. The other large african land mammal I can think of is the hippopotamus. No prizes for guessing how they keep cool. Note that the number of species of large african land mammals is small (I can think of 3 of this scale), whereas the number of species of small animals is massive.

          Camels have a number of specific physiological adaptations that allow them to raise their body temperatures above that of other mammals, thus maintaining a higher rate of heat loss:

          Note that pretty much all of the other mammals living in deserts are very small and subterranean - e.g.hamsters.

          1. Anonymous Coward
            Anonymous Coward

            Re: Re: Re: Re: Utter Testicles

            Wow Wikipedia, that bastion of accurate and scientifically validated information.

            Ever wondered another damn good reason things are small in the desert ? Very little food.

            Large African land mammals:

            Lion, Zebra, Rhino, African Buffalo, Wildebeest, Giraffe and a few more.

      3. chris lively

        Re: Re: Utter Testicles

        Actually, whether dinosaurs were cold or warm blooded isn't "settled science".

        The current prevailing thought is that they were actually warm blooded, but there's not enough data to know for sure.

  18. The Axe

    Other animals

    So horses changed size according to temperature so the theory goes. What about other animals? Any proof that they changed in size due to temperature changes?

    1. Anonymous Coward

      Re: Other animals

      The trouser snake is known to shrink when cold and grow in size when warm.

      1. NomNomNom

        Re: Re: Other animals

        but have you ever seen one in the wild?

  19. Armando 123

    Harumph, I say!

    “Maybe that’s not all bad and if that’s the worst it gets, it will be fine. You can either adapt, or you go extinct, or you can move, and there’s not a lot of place to move anymore, so I think it’s a matter of adaptation and becoming smaller.”

    As someone of Anglo-Viking ancestry, I find this racist and plan to kill the wanker via the Flying Eagle! Hand me the battle axe. Or chainsaw.

  20. Pen-y-gors Silver badge
    Thumb Up

    "bone-bothering boffins"

    Love it! So much more expressive than palaeontologist!

  21. mike9999

    I hate to go off on the compulsory tangent, but:

    "...during the PETM, when concentrations of carbon dioxide in the atmosphere and oceans caused temperatures to get hotter across the planet"

    It's been documented numerous times (unwittingly by none other than Al Gore - he evidently either didn't look at the charts he displayed in his movie very closely or he assumed we were too stupid to notice) that the CO2 levels increased AFTER the temperature rose, not before. Saying over and over again that CO2 caused warming during this period doesn't make it so. The strategy, it seems, is to simply make the subliminal correlation enough times in casual conversation so that it becomes pseudo-intuitive ('everybody knows that!'). *** Note that I'm not saying that CO2 does not cause warming, only that the most often cited segment of the historical record doesn't support it. Using faulty data to support a position merely undermines that position.

    1. NomNomNom

      you are thinking of interglacial cycles that have occurred in the past 10 million years. The PETM is an event that occurred 55 million years ago and there is good evidence that the CO2 rise happened before the warming

      1. mike9999

        ...not according to the available data. But you will continue to believe what you choose to believe.

        1. NomNomNom

          Look it up, the carbon spike occurred BEFORE the warming

  22. Andy 6


    "Global warming COULD SHRINK THE HUMAN RACE"

    I hop ethis doesnt also apply to my winkle.

    I kind of like it the size it is already

  23. jah627

    Warm-blooded animals might need to "shrink" down in response to high global temperatures, but cold-blooded animals (reptiles...insects) would likely respond by getting larger, not smaller....

    1. Anonymous Bosch

      Great. Does that mean the lawyers will get larger?

  24. oneSTARman


    The HUMAN RACE - If Global Warming is Not REVERSED Soon - Will SHRINK from 7 Billion to about 144,000 - FIRST will be FAMINE Then when a Billion Refugees spread PESTILENCE and the Food Riots Start there will be Nuclear WAR and - for MOST of Humanity - DEATH. The Four Horsemen of the Apocalypse galloping towards us in Ten-Gallon Texan Cowboy Hats.

    1. Drewc (Written by Reg staff) Gold badge


      But what do you really think?

  25. CanuckDriver

    Ever heard of the Masai?

    Hmmm... I think this is more bunkum. The Masai live in a very warm climate and they are largely over 7 feet in height.

    1. Ross 7

      Re: Ever heard of the Masai?

      Evolution is not *just* a product of temperature, but many things. The basic rule is that cold temp = low surface area : volume ratio. Think polar bears, whales etc. Penguins attain the same feat by behaviourl means (huddling) - the group has a small surface area compared to its volume. On the other hand we get things like meercats, hamsters, gerbils etc that are desert creatures which are tiny little things.

      The large African animals referred to like elephants, hippos, lions etc don't live in the desert. They live on the plains where it is rather cooler. They also have various mechanisms that help them deal with the heat, which are either things that increase their surface area : volume ratio (huge ears for example) or are behavioural (like sitting in water, spraying themselves with water etc). The reason they are larger are the other benefits of size such as the ability to avoid predation (kinda hard to bring down a bull elephant with just your teeth).

      The Masai still have a pretty high ratio due to them being very slim. Therefore their height alone is irrelevant for this purpose - it's their height *and* their build we need to consider.

      Furthermore tallness granted them the ability to see danger from a greater distance. Therefore, the tall fat ppl and the short ppl didn’t get to pass on their genes. On the other hand the tall skinny folk were more active, having a higher surface area : volume ratio and could see things from afar much more easily being able to see over the grass.

      If there weren't so much tall grass the Masai would be short, but there are other factors than just temp that affect the likelihood of being able to pass on your genes. Compare with the tiny ppl from SE Asia, esp the islands. There’s no real benefit to being tall if you live in the jungle - the trees will always be taller than you. Therefore heat becomes a larger factor and you get 'ickle ppl.

    2. Some Beggar

      Re: Ever heard of the Masai?

      I've spent a bit of time with the Maasai and the Datoga. The men are generally a little over 6' tall. They're certainly taller than average (particularly when compared with some of their neighbours), but I have no idea where you got the idea that they're all basketball giants. The main reason they are tall is that they have an unusually rich and high protein diet through childhood.

  26. Johnny Canuck


    That all the UFO visitations are simply us visiting from the future. As we get smaller our brains and heads remain the same size and our skin will turn gray from less sunlight due to increased cloud cover. So if you see a small gray being with a large head - its just our future selves.

  27. Xris M


    I for one welcome our new tiny.......

    1. Red Bren


  28. gametheoryman

    trying to be misleading?

    Is the discussion on potential implications towards humans intended to be really misleading or is the author clueless?

    Assuming that the science here is spot on (and new scientific understandings never occur with one study):

    1. A significant evolutionary response is likely to take tens of thousands of years.

    2. This response would require that we don't use air conditioning, we don't move, and technological change stop immediately in medicine, in areas that improve conditions for child development, and in reducing the cost of living generally. Historically low technological changes alone lead to the cost of living dropping by more than a factor of 7 in only a hundred years, let alone thousands.

  29. Vladimir Plouzhnikov

    Just nonsense

    As anyone who has ever been to Dubai can attest. If it gets hot we just crank up the air conditioning. Normal evolutionary pressures do not work on humans. Fail.

  30. Andrew Orlowski (Written by Reg staff)

    "like the fact that we're running out of food"

    Ooh, I dunno.

    Maybe we could... grow some more?

    1. OrsonX

      Re: "like the fact that we're running out of food"


      water (lots)

      energy (lots)

      infrastructure (lots)

      willingness and cooperation (lots)

      money and technology (lots)

      oil (lots and lots and lots)

      USA is already eating the 3rd worlds food capacity (in terms of the above resources). If the 3rd world progresses to the same level as USA then as surely as rabbits on an island will run out of food at a given population size, then so will we.

      However, we will run out of water first.

    2. Some Beggar

      Re: "like the fact that we're running out of food"

      We could plant some of these magic beans. Yours for only £500 each.

  31. Andrew Moore Silver badge

    Short humans? I'm reminded of the Itorloo in Raymond Z. Gallun's Seeds of the Dusk

  32. cand.jur

    A wonderful discovery - this may be the negative feedback mechanism we are looking for: (1) Increase in CO2 leads to warming; (2) warming leads to shrinkage of organisms; (3) smaller organisms produce less CO2; (4) less CO2 leads to cooling - and so on.

  33. Bob 18

    Another Factor...

    Large populations evolve more slowly than small ones. At 7 billion, the human population is incredibly large, probably larger than any mammal population in the past. So we're not evolving anywhere very fast at this point.

    This could be changed either if the human population overall shrinks substantially, or if we stop traveling around the globe (which we've been doing, as far as evolution is concerned, for the past 30K+ years). Neither is very likely in the near term.

  34. Joe User

    Heat makes animals shrink?

    Really? Someone forgot to tell the Maasai about that....

  35. Anonymous Coward
    Thumb Down

    No - I disagree

    The oxygen levels were alot higher in prehistoric days (known fact) and it is this decline towards the levels we have now that was a factor in size reduction in animals. As also noted in insects.

    Now we might have to get smaller to be able to sit on the next generation of public transport seating, which gets smaller and smaller each year that by 2025 I expect my kneecaps to be in my face.

    Either way give me a Victorian ceiling hight over the claustrophbia inducing ceiling we have today

  36. Rombizio

    As long as it doesn't shrink my penis....

    I am OK with it.

  37. Tsunamijuan

    Than why are Samoan's so big?

    If thats really the cause they Why are Samoan's so big? I would argue this is also the fact with Texans, and most of the southern US, but I think we have air conditioning and BBQ joints with seats that would fit a cow.

  38. solaries

    shinking humans

    This is exactly the question I asked when I first read this story thanks for the answer.

  39. Some Beggar

    I've done some research of my own.

    I increased from 40cm to 193cm over about fifteen years and have been on an apparent plateau for the subsequent twenty five. Comparing this with the graph of average global temperature over the same period suggests no obvious correlation. Q.E.D.

  40. Anonymous Coward
    Anonymous Coward

    let's get small, really small

    Steve Martin, always ahead of his size, knew small was the answer in 1977...SNL, season 2 episode 14.

This topic is closed for new posts.

Biting the hand that feeds IT © 1998–2019