Posts Tagged ‘natural selection’

As the king of atheism in Leeds (because nobody else wanted the job), On the Origin of Species felt like the kind of book that I should have read. However, I never had, partly because it is basically a biology textbook, even if it is written for a more general audience.

In an exciting twist though I discovered an abridged version by Richard Dawkins which was a manageable length.

It is still pretty dull to be honest. I mean, I am sure if I thought about it, I would have known that there was indeed so much to know about pigeons. However, it is difficult to stay focused on that. Unlike Charles, I have never been a member of one pigeon fancier club in London, let alone two.

I think part of the problem was I just knew it all already. Having been in Humanist circles for so long I had been to enough talks, read enough books and debated the naturalistic side so often that I had a good grounding of evolutionary theory already.

A long time ago, and by that I mean several years ago now, I started an essay on whether humans had stopped evolving. I never quite finished it and due to its length, every time I sat down to finish it, I needed to re-read what I had written so far and then thought better of it.

Well, that has been dragging on for far too long now, since 2008 in fact, so I’ve patched it up with the few final notes I had left myself and decided to publish as is.

I’m sure if I sat down and wrote something from scratch today, it would be better. But never the less, I have some confidence in what I wrote back then, so here it is in its full glory.

Humans are amazing animals. But animals none the less.

One issue which has come up quite a lot recently is the idea that humans have evolved beyond the idea of being an animal into something higher.

Many people make this claim without meaning to or without really considering its implications. I am not talking about the people that claim that animals are merely automatons while humans alone can think intelligently. These people are wide spread, obviously within the religious community but also within the non-religious community to an extent as well but any such argument, at least from an atheist perspective, is clearly rubbish.

However what I am getting at here is people who make claims such as “humans have now evolved to control their own evolution”, “humans are no longer subject to the laws of evolution” and “humans are no longer subject to the wrath of mother nature.”

These claims may seem apparent [to be true] with some thought on the subject but when examined deeper actually come up along the same line of thinking as believing that humans are the only creatures which can think and are self-aware, it grants us a special place in creation which is a perfectly acceptable view within religious communities but one which does not fit with the atheist world view. This would be accepted by all but I suspect the people that make the sample arguments I have supplied would disagree this is the claim they are making.

However, when examined it does in fact come down to this point of view. So it is important I think that I address the points made on this line of thinking to explain why I do not believe this to be the case. Humans are still animals, we are still subject to the laws of evolution and we still play within the framework that all life does.

I believe one of the problems which lead to this line of reasoning is that we assume the same metrics used to measure what we would consider a successful person within society are equally good metrics for measuring how successful someone is in terms of evolution. In this case it is a far more simple equation – who is likely to survive and breed the most.

Take for example, the chav. In today’s society they are considered the bottom of the pile. They are uneducated, unmannered, annoying and often regarded as a group we would be better off without. It therefore seems perplexing to many people that chavs are breeding faster that well mannered well educated individuals because this suggests they are the next stage of human evolution.

The mistake here is, as stated above, that we use the same metrics to measure value in society as to value from an evolutionary perspective. Considering the problem from an evolutionary perspective, the chav is indeed the next stage of human evolution. Why? Because they are better at surviving and breeding than the smart highly educated yet less sexually promiscuous individuals (probably such as you and me if I am so bold as to make a judgment about my readership). A lot of people would at first laugh when it would be suggested chavs were the next stage of evolution but why should it not be true? How self righteous is it to presume that you must be the next stage in evolution?

As it happens in this case chavs probably aren’t the next stage of evolution. The reason for this is that there are questions raised as to how an entire society of chavs would fair and I shall return to this later but for the moment I would like to move on as this is somewhat of a side track, it does not illustrate my argument in the best way but more stands alone as an important point.

Returning to my original argument, humans are in fact in no special way in control of their evolution or protected from mother nature. Every year millions of people around the world perish in natural disasters. Of course many do not because of the efforts of mankind but this is no different than to the animal race. They too are fighting for survival and they too have a degree of success with this. Our degree of success is generally regarded as higher – but it is all on the same scale.

For example humans build themselves tools and shelter to protect against the wrath of mother nature. We have flood barriers, shelters from hurricanes, etc. But of course animals build themselves shelter too. Take a look at the humble ant, building mightly ant hills to protect themselves. These are not always successful, just as man’s efforts are often unsuccessful when mother nature claims lives in floods, earthquakes and volcanic eruptions. Both are “artificial structures” created by animals to live and shelter in.

Secondly I believe the idea that humans are now in control of their own evolutionary path is equally flawed. One of the prevailing arguments for this is that people within our society who would not survive in the animal world now survive in our society such as people born with severe disabilities.

However much like the uneducated chavs, severely disabled people rely on the infrastructure created by society in order to support them. It is a fantastic feat of human advancement and kindness that we are now able to keep alive and care for the severely disabled. But they no more form the next step in human evolution than they ever did. A society consisting purely of severely disabled people would be unable to survive effectively. Similarly a society solely consisting of uneducated chavs would be without the medical, engineering and logistical knowledge required to make modern society function effectively. Therefore the idea that human evolution will not continue along the natural path is simply unsubstantiated. Society is not about to devolve into chavs or people unable to look after themselves – the bulk of the population will remain fit, able and evolutionarily advancing individuals.

Further along this line of thought, it is worth noting that society’s apparent lack of potential to evolve further is also false. Take for example a change in the climate. Let us say it becomes colder, there is a global drop in temperature. Many people would claim this shows that human evolution has stopped because while animals (a term taken to mean non-human animals of course) would evolve thicker fur or a similar evolutionary trait, humans would simply manufacturer themselves thicker coats.

This at first glance seems to make sense but on closer examination does not in fact stand up as an argument. The main reason for this is that evolution covers the adaptation of a species – it does not state how this adaptation has to occur. Therefore, humans manufacturing themselves thicker coats to survive the cold is the human race adapting to better survive in it’s environment. It is not a case of us “breaking” evolution, it is a case of evolution happening right in front of our eyes.

This is often disregarded as it is seen as something external to us ourselves as evolving but when some thought is put into such arguments it does not seem to hold much water. Furthermore this is likely to be less true in the future as the “artificial” or “external” advancements we make become far less external as we begin to alter our own genetics and breeding ourselves fitter, healthier and better able to survive.

As we’ve already established, you have to accept humans as just part of nature, and once you do, it’s very difficult so say, “oh, that isn’t part of nature” when we do something. Animals make nests to live in and sometimes use basic tools – how is that any different to the more advanced tools we use?

Evolution seems to be continuing on humans unabated. Take, for example, height. We’re definitely getting taller as a species. If you compare the average height of someone a thousand years ago, they were shorter than we are today – and that is entirely natural if you will.

Mutations also occur at just the same rate as they ever have. Just because we’re moving faster with our own technology and improvements to life, doesn’t mean that the classic methods of evolution have stopped – mutations occur at just the same rate as they ever have. The reason it seems to be happening could perhaps be to do with the fact that it’s a very slow process and as humans we’re used to things advancing increasingly quickly.

Our basic desires also still drive us. Deep down we all still want to find a mate and have babies. It’s wired into us and the majority of people over the age of fifty will be happy to tell you that at a certain point, you just get the urge to procreate. We might be master of many things as a species, but we haven’t wiped out our basic emotions yet (and probably never will, unless people start seeing Vulcan as the ultimate utopia).

Therefore to summarise, my points are as follows. Most of us will agree on the premise that humans are animals and have no divine special place in the universe, we’re just doing pretty well. Once we agree on this there is no reason to believe that we are not subject to the laws of evolution, that we have somehow stopped evolving or that we now control mother nature.

In my post on the taste of meat I briefly mentioned the problem of homosexuality and natural selection. That is to say, why does homosexuality persist, given you think natural selection would weed it out because gay men are not having babies and therefore not propagating their genes.

Many people have taken this to mean that homosexuality is some kind of defect, where something has gone wrong because the ultimate goal in life is making babies and these people aren’t doing it.

Luckily, Rich had written a talk to explain all about it. Having first delivered it at Rationalist Week 2009 he also delivered it to Leeds Skeptics later that year.

I’ll skip the interesting, but never the less skippable introduction and get straight to the answer.

Genes do different things based on their environment. So in one person with one set of genes, a specific gene may do one thing – but take that gene out and put it in someone else with a different set of genes and it may well do something else.

This is what we find with the so-called gay gene. In men, it is more likely to make them homosexuals. But put that same gene in a woman and it actually makes them more fertile. Therefore a woman carrying the gay gene is more likely to have children and even though some of them may turn out to be homosexual men, the women will continue to propagate the gene because of their increased fertility.

There are other factors at work as well of course – homosexuality is a combination of both nature and nurture. Having the gay gene doesn’t mean you will be gay – it just increases your chances. But that is Rich’s argument as far as the genetic side goes.

I’m a vegetarian. And I think everyone should try it.

The problem is though, it’s very heard because steak tastes so good. So do ribs. So does chicken. And many, many other meat based foods. Meat tastes amazing!

So here is the question – if vegetables are so good for us, why don’t they taste amazing? Think about it from an evolutionary perspective – if you had a human who preferred eating food that was good for them, then they would prosper, so you would expect natural selection to lead us to humans that love vegetables because they are really good for us.

But we don’t have that, we live in a world where many people eat vegetables because they are good for us but enjoy eating meat far more.

This seems strange, much like the problem of natural selection and homosexuality, and much like that problem, I’m sure there is an answer to it.

My guess would be this – back when humans were evolving, there was a lot of plant life and vegetables to be eaten. Humans didn’t actually have to like them to eat loads of them because they were the most abundant food source and so people ate plenty of vegetables anyway, by default almost.

People do need a bit of meat though, or at least, did in those days, and that was much rarer and indeed, harder to get hold of. So it had to taste good to motivate humans to go out and hunt down animals for meat.

Of course, that could all be nonsense, that’s the best-educated guess I can come up with sitting here as a computer scientist with a casual interest in evolutionary biology and the combined knowledge of the first two chapters of Richard Dawkins’ Climbing Mount Improbable.

Another reason is that it could just be an accident of the way that the human taste sense has evolved and the texture of meat. Maybe someone who studies biology can enlighten us?