Musings on evolution, observations of the evolved

Posts tagged ‘human caused extinctions’

Our Unique Responsibility

I thought I’d write a bit about some of my thoughts on conservation issues, with a particular emphasis on humans as part of the natural world, rather than the way we’re normally seen as something separate. There’s so often a distinction drawn between the natural world and the human world, but I personally think it’s more useful not to make the contrast, since it doesn’t really exist. I’ll also pose a few questions – ones which need answering for each of us to decide where our own thoughts lie.

Extinction is a perfectly natural thing. It’s happening all the time and it’s often one species that causes another to cease to be. One well studied example of this is the Great American Interchange. North and South America were not always joined together – the Isthmus of Panama only linked the two some 3 million years ago, and the previously separated ecosystems were able to mix together. Species migrated both north and south, and there were ultimately bound to be winners and losers – some extended their ranges whilst others became extinct.

Humans also cause extinctions. Homo sapiens – modern humans – evolved around 200,000 years ago in eastern Africa, and began to spread across the globe around 70,000 years ago. They were immediately successful, and proficient hunters – and so began the extinctions of the hunted. But is this to be viewed as a completely natural event? Personally, I don’t see a great deal of difference between this and other extinctions such as those when the Americas joined up, but fast forward a few years and perhaps things need to be viewed in a different light.

I see two major differences. One is the sheer scale of our impact. Not only do we hunt other species to extinction but we destroy vast areas of habitat for our own use, we kill for our own pleasure and we contaminate with chemicals that pollute or alter the world. Though I think these things could still be seen in a natural context – on an individual basis we are just driven by the universal desire to survive and reproduce. However, the other difference is the one that makes us unique. We are the only species to have a consciousness of ourselves and the impact we have on all that is around us. We are the only one to be able to look beyond our own immediate needs and develop a morality concerning the wider impact of our actions.


So are we to blame, are we at fault? If our actions are simply driven by individual desires of survival in a naturally competitive world, but our collective actions have major negative effects, then surely not. The situation could be compared to evolution. Evolution is driven purely by an individual’s desire to reproduce and pass on its genes to the next generation. Consider a predator for example. It might evolve to run faster and faster to be able to catch its prey. In doing so it might become so successful that it causes the extinction of that prey species, and in turn causing it’s own demise due to lack of food. This sort of scenario happens all the time – evolution has no ability to foresee such problems, it only works on individuals, with the destiny of the species as a whole left to an uncontrollable fate. Humans have only very recently become aware of the problems we create, so should we be let off the hook as far as blame is concerned? Is it no surprise we struggle to deal with the issues when individually we still have to look after our own survival?

So what are we to do with our recently acquired awareness of the wider consequences of our actions – we have no other species to look to for guidance. Undoubtedly we have to make some changes. I think we can draw a distinction between two types of environmental preservation. There is that which looks after the world around us because we know that if we didn’t there would be negative consequences for ourselves. I guess we’re still talking about self preservation here, but one which is more forward looking. Then there is the idea that we should look after things simply because we feel it’s wrong to make other species extinct. Now we’re talking about true altruism, and that’s also something which is probably unique to humans. Altruism goes against the theory of evolution entirely. It either doesn’t exist in the non-human living world or it’s very rare. If an organism does do something to help another (and they very commonly do) then it only does so because it will get something in return (or to put it slightly more precisely, it’s genes will benefit).

One big question is – how much of our thinking about conservation should be driven by this altruism? To put it perhaps slightly more cynically or controversially, is it really quite so altruistic as we might think? If a huge amount of time, effort and money is spent on a specific project to preserve a particular species, how much of the motivation to do this is driven by the fact that we like the species, we find it impressive and we personally want it to carry on existing? Surely there is at least some degree of more self serving thinking going on here.

Take for example the current situation with the decline in bee populations. There’s quite rightly a great concern for what’s happening, but it is very much helped by the fact that there is a lot of warm feelings towards bees. But what about the poor old wasp? OK, it’s not in the same danger, but if it were, would there be as much attention paid. In evolutionary terms it’s very close to a bee, there’s really not much difference between them. Few people like a wasp, and I must admit, I’m as guilty as anyone – I don’t really want them around if I’m honest. But an beautiful hornet on the other hand – now there’s an impressive beast. There’s a lot of inconsistent thinking going on somewhere.

So what of the future? Can we stop even bigger problems arising? The issue really boils down to human overpopulation, bringing us back to that ever present individual desire to survive and reproduce, and this being at odds with the bigger picture. I liken it to economics. Individuals struggle hard to earn money, and borrow even more because it’s the only way to buy a house, but eventually the bigger system breaks down and the bubble bursts, and we have recession or depression. Individuals have to act in a certain way to get by, but that way causes downfall in the longer term – just like the predator running too fast. Surely something similar will happen with the human species. We’ve not got there yet – overpopulation has caused problems but nothing genuinely catastrophic. But it’s still marching on and who can predict the problems of the future.

It was reading about Malthusian thinking that led both Darwin and Wallace to come up with their theories of evolution by natural selection. Malthus wrote about the way human populations are kept in check by limits on the amount of food available and by disease. Our abilities to combat those limits mean that the population goes on growing. But one day will some kind of Malthusian disaster finally come home to roost? One thing we now know is that every species that exists becomes extinct eventually, and a similar fate will befall humans one day for certain. But when and how will it happen? Not for a long time I’m sure, but in the meantime we do need to look after all that is around us. And sorry, there do seem to be rather a lot of questions to answer.