The slelfless gene? Has the selfish gene gone away?
In a recent article "It's time to get skeptical about the ""Selfish Gene""." Richard Dawkins book was taken to challenge, but not as much as many would think. The discovery in recent years that evolution can be driven by environmental factors has changed some thinking but not all. There are many dynamics on how genes work, and as much as we think we have figured out, we are still figuring out so many more.
Environment does play an important role in evolution. In certain environments genes which function for specific traits work well, or work enough to pass on, so here a selfish gene is fine. But in another environment, it doesn't work at all, so no matter how selfish that gene is, he is likely to be the one passed over, and possibly silenced or even bred out of the population.
What people fail to understand is that there is not 1 selfish gene, but 10 books worth of selfish genes. When a gene is expressed and amped up, it is usually in a physical way. So the body has to demand more of something, let's use horses for example. Say that you are the ancestor of modern horses in North America, and you live in the trees, being small is not so bad, you can scurry, without hitting your head. Not only that the gradual change of evolution has been going fine, you can run and scurry under the bushes and hide from predators.
Suddenly the forest begins to die back and grass lands start coming on, and by suddenly, I mean a few hundred years, so it is not you but generations of your kind that undergo this new pressure. Now there is no cover, no bushes and shrubs, and the only thing keeping you from going extinct is how fast you can run. Well the guy who lacks that fast gene is usually the first one eaten. As your species gets faster and bigger, so do the predators, because only the fittest survive.
How did we get here though? Well that selfish gene had to be present in the population for it to be passed on, now everyone had it. With environmental stress, it forced your species to adapt, get bigger, and faster, so in a line we can watch as you do so. Because the fittest were always those that were a bit taller, but not too tall, and fast, but not clumsy. So some genes were selected for, and they became the selfish guys when the need arose.
But a gene is never alone, they are surrounded by plenty of other genes that are just as selfish. Think of the chromosome as a map, from the head down, end to end it has your whole body plan mapped out, and it is not the only one, there are other versions of you waiting to express. They just don't because these are the ones that express the best, and function in a way needed, but if the environment changes, you have back ups waiting in the wing to be the next guy selected.
We have seen this selection in action now a few times, environment plays just as much a role n who you are as the genes you carry, but if you don't have a gene, or it is not there, the best you can do is adapt with the ones you have, and that is not always good enough.
Richard Dawkins is not wrong, it is just that we have added layers to the selfish genes and what they do. We have gone from just seeing what makes us want to pass on our genes and why they want to, to knowing that we face outside factors to our survival, and there is many more layers. Proteins play a role in which genes are acted on, and how they are acted on. We aren't simple, as complex organisms, we are highly complex, and we still don't understand everything, for example a viral infection can trigger the expression of genes that were dormant before. They can leave viral DNA in our genetic code.
Dawkins book highlights an important part of evolution, when it is static in its environment but with global changes and environments disappearing we are finding things can adapt, but not always. Genes have to be in the population to be expressed in it. Sure we might end up with a species that looks nothing like where it was a while ago, but the thing is, that has driven evolution for billions of years. We are no closer to e-coli than we are to snakes, but we are. Shared DNA doesn't make us that species, but it doesn't make us far removed from it either, it is all in the genes and gene function, expression, and dominance.
The thing is to be a biologist, you have to know what we know now, but you can't know what we don't know yet. Just like Charles Darwin was not aware of DNA, we see that some of his writings are relevant and that other parts have been disproven, while Dawkins writings are still relevant, parts of what we once believed as the only mechanism are being updated, and we now know there are more. It doesn't make his book past its time, it makes it a beginning on a long journey. One we will be taking for the next few hundred years, and more.
Environment does play an important role in evolution. In certain environments genes which function for specific traits work well, or work enough to pass on, so here a selfish gene is fine. But in another environment, it doesn't work at all, so no matter how selfish that gene is, he is likely to be the one passed over, and possibly silenced or even bred out of the population.
What people fail to understand is that there is not 1 selfish gene, but 10 books worth of selfish genes. When a gene is expressed and amped up, it is usually in a physical way. So the body has to demand more of something, let's use horses for example. Say that you are the ancestor of modern horses in North America, and you live in the trees, being small is not so bad, you can scurry, without hitting your head. Not only that the gradual change of evolution has been going fine, you can run and scurry under the bushes and hide from predators.
Suddenly the forest begins to die back and grass lands start coming on, and by suddenly, I mean a few hundred years, so it is not you but generations of your kind that undergo this new pressure. Now there is no cover, no bushes and shrubs, and the only thing keeping you from going extinct is how fast you can run. Well the guy who lacks that fast gene is usually the first one eaten. As your species gets faster and bigger, so do the predators, because only the fittest survive.
How did we get here though? Well that selfish gene had to be present in the population for it to be passed on, now everyone had it. With environmental stress, it forced your species to adapt, get bigger, and faster, so in a line we can watch as you do so. Because the fittest were always those that were a bit taller, but not too tall, and fast, but not clumsy. So some genes were selected for, and they became the selfish guys when the need arose.
But a gene is never alone, they are surrounded by plenty of other genes that are just as selfish. Think of the chromosome as a map, from the head down, end to end it has your whole body plan mapped out, and it is not the only one, there are other versions of you waiting to express. They just don't because these are the ones that express the best, and function in a way needed, but if the environment changes, you have back ups waiting in the wing to be the next guy selected.
We have seen this selection in action now a few times, environment plays just as much a role n who you are as the genes you carry, but if you don't have a gene, or it is not there, the best you can do is adapt with the ones you have, and that is not always good enough.
Richard Dawkins is not wrong, it is just that we have added layers to the selfish genes and what they do. We have gone from just seeing what makes us want to pass on our genes and why they want to, to knowing that we face outside factors to our survival, and there is many more layers. Proteins play a role in which genes are acted on, and how they are acted on. We aren't simple, as complex organisms, we are highly complex, and we still don't understand everything, for example a viral infection can trigger the expression of genes that were dormant before. They can leave viral DNA in our genetic code.
Dawkins book highlights an important part of evolution, when it is static in its environment but with global changes and environments disappearing we are finding things can adapt, but not always. Genes have to be in the population to be expressed in it. Sure we might end up with a species that looks nothing like where it was a while ago, but the thing is, that has driven evolution for billions of years. We are no closer to e-coli than we are to snakes, but we are. Shared DNA doesn't make us that species, but it doesn't make us far removed from it either, it is all in the genes and gene function, expression, and dominance.
The thing is to be a biologist, you have to know what we know now, but you can't know what we don't know yet. Just like Charles Darwin was not aware of DNA, we see that some of his writings are relevant and that other parts have been disproven, while Dawkins writings are still relevant, parts of what we once believed as the only mechanism are being updated, and we now know there are more. It doesn't make his book past its time, it makes it a beginning on a long journey. One we will be taking for the next few hundred years, and more.
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