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There is no doubt about it – there is visibly ongoing evolution all around us: in hospitals where pathogens such as MRSA have evolved by adapting to the new environment of antibiotics, between your toes where the athlete’s foot fungus needs a different treatment from last year, and in mosquitoes evolving pesticide resistance while pharmaceuticals play catch-up.
Evolution is too fast for us. Species of East African cichlid fishes that took hundreds (not millions) of years to evolve now look like hybridising to produce even newer species faster than the funding arrives for observing them.
Rapid environmental change increases selection pressure and adaptive change follows. Human intervention to change the rules of fitness may be ‘artificial’, but the selection mechanism is the same.
While history speculates on how long it actually took to domesticate dogs, modern experiments produced friendly tail-wagging floppy-eared patchwork puppies from wild foxes in 20 generations just by selecting for tameness. 20 years from wild pest to soppy floppy pet: Russian scientists have done it!
There’s no sharp divide between natural evolution and response to man-made environmental change these days. To see evolution in action on a large scale, we could just carry right on and watch the biosphere adapt to Global Warming. I hope that will NOT be in our lifetime.
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Comments on: "Evolution - right here, right now"
Rob Wheeler has started a thread discussing Evolution - right here, right now.
Evolution - right here, right now
Academics have said that we can see evidence of evolution almost happening in real time - do you agree? Have you seen any similar evidence?
http://www.open2.net/darwin/darwin/evolution_now.html
Re: Evolution - right here, right now
Hi Brian
Interesting that you've worked in archaeology - fascinating subject. I agree that, were you to take a sample of individual humans from pretty much anywhere in the history of Homo sapiens, their individual intelligence would be pretty much the same. You're right - we often forget how much of what we define as advanced in our lives emerges from the interactions between ourselves and others and with our transmitted culture and technology. The mistake of equating evolution with some ill-defined notion of 'progress' has been a problem in our understanding of both evolutionary biology and archaeology/anthropology.
However, I think we need to be pretty careful about definitions here. In particular to be careful to distinguish biological evolution that occurs through the inheritance of genes and cultural evolution that occurs through the inheritance of ideas/knowledge/customs etc. I think a lot of what you're discussing here is more to do with cultural evolution. Coming back to the original question of the thread, there is abundant evidence that humans are the product of biological evolution and are probably still subject to natural selection (if perhaps less so just at the moment - see the articles on this very point on the open2.net website: http://www.open2.net/sciencetechnologynature/worldaroundus/evolution_p.html). And you don't need to go back too far in time before natural selection would have been a major force even in societies that are currently technologically advanced. Pre vaccination, pre antibiotics and pre NHS there were significant rates of mortality before the age of reproductive maturity.
The 15% of the brain thing, by the way, is a bit of an urban myth. The brain is much too energetically costly to be doing nothing - it would have been reduced in size pretty quickly in our evolutionary history if 85% of it became vestigial. In fact brain-imaging and brain-metabolism studies show clearly that it's all active.
Paul
(Invited Contributor)
Re: Evolution - right here, right now
Is there a difference between adaptation and evolution? I know there's some people who are getting very good at running, say, but wouldn't it take time for us to know if that is a true evolution - at least to see if it gets passed down the line as they breed and have children?
Re: Evolution - right here, right now
Well 'Jaws' is a good word to illustrate an example of adaptation, by orthodontic improvement, to social requirements, without evolution. Runners also adapt to their strenuous exercise by developing bigger muscles, and whole communities can be very good at this such as in some parts of Kenya, but as you say it's not evolution unless the next generation shows more of that selected ability than their parents' generation. Evolution is what you see in whole populations, generation to generation.
Re: Evolution - right here, right now
Of course one of the classic examples of natural selection happening over a short (to us) timespan is industrial melanism in the peppered moth. I'm sure anyone coming to this forum knows the background (try http://en.wikipedia.org/wiki/Peppered_moth_evolution if not). Recently the explanation for industrial melanism has been attacked - some of this being justifiable criticism of the experimental design of the early studies. The results of a new study by Michael Majerus which addresses these problems are just starting to come out and it's pretty clear that natural selection is occurring in this case. The whole thing is discussed very nicely in an article in New Scientist (http://www.newscientist.com/article/mg19626330.500-reclaiming-the-peppered-moth-for-science.html) and there is a direct link to Majerus's work at http://www.gen.cam.ac.uk/Research/majerus.htm
Paul
(Invited Contributor)
Re: Evolution - right here, right now
Hi Valerie
Just for fun I was thinking about what you said on the subject of orthodontics and whether there might actually be a way natural selection could have an influence here. Of course, one of the dangers to be avoided in thinking about evolution is the making up of plausible-sounding stories without any evidence but anyway, as a bit of fun....
Clearly if the state of your teeth has no influence on your survival and chances of reproducing there is no way for natural selection to work and I'm sure that's what's actually happening. And, of course as you say in your post, getting your own teeth fixed is not going to directly and immediately improve the teeth of your children. But supposing there was a slightly increased risk of dying while you were on the dentist's chair getting your less-than-perfect teeth fixed. This might be enough to give those with genetically good teeth (who don't need to run the risk of having their teeth worked on) a selective advantage and so over a long time period the average quality of a population's teeth might improve - especially since most orthodontic work is carried out in childhood, before people have had a chance to pass on their genes.
However, the whole thing is probably overshadowed by the increased chance of reproducing if you've had your teeth straightened! In which case, the state of teeth will probably stay pretty much as it is.
Does anyone know if there is any data on this?
Paul
(Invited Contributor)
PS Before my dentist reads this and sues me, I am NOT suggesting it's dangerous to go to the dentist! It's just a thought experiment.
Re: Evolution - right here, right now
Hi Paul.
Although as you correctly say, the trait for geed teeth will not be passed on to your offspring if you cheat and have cosmetic dental work done. However, what is likely to be passed on is the trait that is willing to take the risk of the dentist’s chair and so is the trait which selects a mate with good teeth (so long as the dental work is carried out before the couple select each other).
Cosmetic dental work does not come cheap (apparently) and what may also be passed on is the means to acquire the required funds, by that I mean business acumen which in the modern world could be seen as the equivalent of being a successful hunter gatherer.
Jonah
Re: Evolution - right here, right now
Dear Jonah,
That's an interesting idea, that could make sense in terms of one model of sexual selection - condition dependence - for which the peacock's tail is a classic example.
We know from years of work with peafowl by Marion Petrie that females prefer males with the largest tails with most colour spots. Yet it seems that the heritability of tail size and spot number is low, even allowing for age-dependent variation - so what are the females actually selecting for, if not 'showy tail genes' per se? Because such showy tails are physiologically 'expensive' to grow, their size and glory are very much susceptible to the general condition of their owners, especially the extent to which their resources are otherwise drained by parasites and disease. So what the females are effectively going for are males who have a good 'all-round hand' of genes for keeping such pathogens at bay - i.e., the tail is a sort of all-purpose signal for 'good genes'. So one could speculate (and I warn that that is what I'm now going to do...) that in (social) humans, the equivalent signal has long been power over resources, or in its modern symbolic guise, loadsamoney (as Eartha Kitt so trenchantly explained all those years ago). Expensively done-up teeth might then just be one particular dialect of that language...just like you suggested?
Peter
Re: Evolution - right here, right now
Thanks for the reply Peter.
I guess what your saying is that a measure of good genes is how much of your resorces youn can afford to spend on non assential traits. In the case of the male peacock, at the expense of his immune system and in humans, at a finacial expense.
So could the same theory be used to explain flashy cars and the like?
Jonah.
Re: Evolution - right here, right now
Peter has shown the sophistication of the peacock-tail story; the hens seem to go for a combination of inherited showiness (although heritability of tail splendour is apparently low) and current wellbeing (few parasites, good nutrition etc. allowing full expression of what tail potential they have). That sounds like a good combination to compare with human preference: inheritance of attractive-enough physique not depending too much on health (helps in the changeable future), and current wellbeing showing that he can cope well with the here-and-now. According to the Zahavi handicap principle, an ideal partner should be a sound enough long-term proposition but show ability to be extravagant now as Jonah said.
Flash cars however are ambiguous in the here-and-now; he can afford it but is environmentally irresponsible. Possibly strong with imperfect teeth, an annual train season ticket, and offering a diamond engagement ring? Sorry, a bit facetious: the cost of orthodontics is far from funny.
Re: Evolution - right here, right now
You bet evolution is working here and now. In the 1950s insect deflectors were put on car bonnets to stop the almost constant splatter on to the windscreen. Sprays were used to soften the dried on corpses to remove them. So why are there so few cases of splattered insects on today's cars? You've got it. Those insects that were very attracted to car headlights were killed by the trillion. They were unable to reproduce. Those insects which were less attracted..... Look, do I have to explain to you how evolution works?
Re: Evolution - right here, right now
Thanks for that example that I'd not included in considering this question, and I'd like to see some research on this very topic, comparing insects from windscreen-kill with the same species in a road-free area. I fear it would be quite an extensive investigation because there are so many potential complications arising from differences in population size, urbanisation, effects on predators of the insects, and perhaps now climate change, all potentially changing the number of insects around roads since the 1950s. It would be easier if someone had preserved a lot of the splatted corpses.
I did read somewhere though that research on hedgehog behaviour had found evidence that their response when frightened by an approaching vehicle in the dark has changed. Apparently the probablility of running instead of curling up has increased, which would demonstrate natural selection as you have suggested.
Re: Evolution - right here, right now
Does it not bother anyone that Darwin's theory, which has been modified to “fit in” with new scientific discoveries countless times since its conception, is completely disproved by both the first and second laws of thermodynamics?
Re: Evolution - right here, right now
Hi Amanuensis
I think Jill is right in that it would be useful to know exactly what argument you are making about the laws of thermodynamics as it may be something new. However, I suspect you are referring to what is now an old argument, due originally to Gish I think, and which, as Valerie has said, disappears once you realise we are dealing with an open system rather than a closed one.
More interesting is the implication in the first part of your post since it raises one of the most fundamental splits in how people think about evolution and science in general. If you are used to accepting a single, permanent, perfect explanation that is right beyond question, then any good evidence that that explanation is wrong, even in the smallest detail, immediately destroys the authority of the whole. Changes in interpretation may be allowed but the original statement is still unchanged and perfect. However, science does not work like this. The explanation of the universe offered by science is knowingly imperfect and incomplete. Some parts of that explanation are very well supported by the available evidence and so can be accepted as more likely to be correct. Other parts are more uncertain, usually due to a lack of convincing evidence one way or the other. That a scientific explanation is modified to fit in with new discoveries (i.e. empirical evidence) is exactly its strength. This does not mean it was entirely wrong before, only that it was untested against the evidence and/or it was not as extensive. Copernicus realised the Earth must revolve around the Sun. The later realisation that the Sun is not the centre of the universe does not make that wrong, it simply makes our understanding broader and more encompassing - literally in this case. The great contribution of Darwin and Wallace was the theory of evolution by natural selection. As befitting a great scientist, Darwin originally phrased much of his explanation cautiously since the theory was then largely untested. Since then an overwhelming body of evidence has supported the bulk of what he suggested. Of course, what Darwin wrote in "The Origin Of Species" was not a complete description of evolution (he never claimed it was) and our understanding of the process has been extended in the light of new tests and new evidence - that is science. Even the finding that under certain circumstances processes (equally naturalistic) other than natural selection dominate evolution does not mean natural selection does not occur and is wrong.
Sadly, the general misconception of science as just a collection of categorically stated facts doesn't do much for enlightened debate.
Paul
Re: Evolution - right here, right now
Jill's a bit harsh because the notion of evolution [well of Life, re. which evolution is automatically inevitable] somehow challenging the Second Law is not daft so much as incomplete. Life is not a closed system - indeed the constant inflow of solar energy [pricipally the blue and red light for photosynthesis] is crucial. Apart from a few strange ecosystems eg. those around sub-ocean 'black smokers', the Whole Of Life is dependent on energy from afar, so however much complexity we perceive around us and from us, there is no wierdly spontaneous decrease in entropy. It's driven, at the expected energy cost within the sun. Evolution is part of the engine.
Re: Evolution - right here, right now
Not harsh enough I think. The point being the original comment was that Darwin's theory was disproven and indeed was in conflict with the 'Laws of thermodynamics'. It is not a good science discussion if someone makes such a claim without explaining how this is so. Otherwise it is just an unfounded comment, and the liklihood is of course, it was a wild comment thrown in with no truth behind it all. Such comments just confuse people who are not aware of what the Laws of thermodynamics actually say. I was simply inviting the writer to explain their reasoning. I have no knowledge of what can be behind this statement and believe it to be incorrect. They have not explained so far, and hence the longer the silence, the more likely this is to be a wild and unfounded statement. I wait with interest....... Jill
Re: Evolution - right here, right now
What a strange thing to say. If it really has been disproved by other well accepted theories, then it would no longer be a theory itself!
I think you are going to need to explain the laws of thermodynamics and exactly how these disprove Darwin's theory..... then wait for the laughter!
Jill :-)
Re: Evolution - right here, right now
There are a lot of ideas in your post, Brian, and I'm sure we'll come back to all of them in lots of detail over the lifetime of the forum. But to try and keep things going here...
First of all there's the idea of humans being something special, which is an idea our species seems desperate to cling to and something perhaps worth a thread of its own. One of the implications of Darwinism is that there is no fundamental, qualitative difference between humans and other animals - an idea many still resist and find particularly disturbing.
If humans are animals, you would expect them to be subject to evolution and this is the more specific question raised by your post. It's an interesting question whether humans are continuing to evolve (and something Steve Jones in particular has written about - are you there, Steve?) but one very important thing to remember is that the observations that might make you think humans have not evolved (such as [partial] control of the environment etc.) have only been possible very recently - at most a few tens of thousands of years if we're talking about the most fundamental kinds of technology such as fire. Even in the UK where you are, survival through the winter was difficult for many people until very recently (at least on an evolutionary timescale).
It's also important to remember that evolution is not simply about survival but about reproduction. Leaving aside the fact that this has been important during the course of Hominid and pre-Hominid evolution, it can be shown that even in modern society the processes of sexual selection are at work - perhaps more to do with changes in culture (and cultural evolution is another topic worth its own thread) but in some cases also to due with organic evolution - the significant tendency for height to be important in the choice of partners, for example.
So, basically, while modern technological society may lead you to think that humans may not be evolving much at the moment (if at all), there is abundant evidence that we are products of evolution and much of our behaviour only makes sense when seen in the context of our evolutionary history.
Paul
(Invited contributor)
Re: Evolution - right here, right now
Hi Paul
Many thanks for your post.
One thing that I've learnt over my six score years plus ten,is that nothing lasts forever.That includes civilizations which includes our own.
I can tell you that Burrow Mump on the Somerset levels stands on a latitude which has the Cosine of 0.2 Pi. when Pi. equals 3.14181818181, that is (22 / 7 ) x ((55²-1) / 55²)) .This is one example of my many finds during my 29 year research of mathematics and geometry hidden in our pre-history monuments. These were constructed by people with intelligence as equal ,if not more so , than our own.
Over the many million of years that Earth has been turning,there could have been many civilizations come and gone and this probably explains why we use only 15 % of our brain power.(How this is mearsured ???)but this apparently is an accepted fact.The other 85 % must have evolved at some stage or it would not be there.
The majority of us assume that we represent mankind in its most intelligent form ever.Sadly (I believe) that this is not the case.A true civilization has wisdom as its foundation stone,not technology created by the few.To go to war is the most uncivilized act possible,B.T. had it right,"It's good to talk".
Am I correct in thinking that once mankind uses 100 % of its brain power there is then a case for evolution to proceed?At the current time,we are struggling to get back to where we were.
Brian.
Re: Evolution - right here, right now
It seems to me that all of nature has evolved to live life on earth with all that the are born with,no more no less,and it would seem that evolution has done them well, what ever their environment may be.Whatever the time of year,the dog can go for a walk without putting his wellies and warm socks on even if the snow is 1m deep.
Mankind on the other hand,has to keep their environment finely tuned. To cold and we suffer hypothermia and to hot and we get skin cancer.Right now,here in the U.K., we are destroying the world by trying to keep warm while others have the air conditioning swiched on.I can see no evolution in this.If there is,it's working against us.
Mankind is a complete misfit when compared with all other creatures of the earth and I can not see where or how we could have been involved with any form of Earthly evolution.
Brian