No Sluggard

You were brought up as a Christian, I understand. When did you leave all that behind you?

I was raised in the Southern Baptist Convention, which is evangelical and also tends to fundamentalism. I ‘went under the water’ – that is, I was baptised – at the age of 14 and – how shall I put it? – I was a faithful boy. But as I approached late adolescence I became more and more familiar with science, including evolution, and my faith just fell away – as happened to Darwin himself, by his own testimony, after he graduated from Cambridge. By the age of 17, 18, I really wasn’t much interested in religion anyway and it was exhilarating to me to learn that the subject that I loved the most, which was natural history, was much more congenial to a secular evolutionary approach. And that’s how I made the transition.

What was the appeal of science for you?

From an early age, I just was fascinated with exploring for plants and animals. When I was a little boy, I dreamt of going to the Amazon and other faraway places and finding wonderful things. And I have never changed. I have just got back from a five-week expedition to the South Pacific, taking a team of three others to the same sites that I worked in 57 years ago on Vanuatu and New Caledonia; and that was a wonderful experience.

I think that all inventive scientists who succeed in developing new theories and conceptions are driven by a passion to go somewhere and discover something of a virginal nature, of liminal life, things unexpected and of constant surprise. But then you go from a fascination to a scientific investigation and description of phenomena. You develop a theory about what is going on and then you find a way to test it. If it works, that’s good – and if it doesn’t, you go back to work again.

Does it puzzle you that other biologists retain their faith, and even say that it has been strengthened by their research? I’m thinking, for example, of Francis Collins.¹Interviewed for High Profile in 2008

You can be a very good scientist, you can even be a great scientist, and remain a religious believer; but in the present day you would need to compartmentalise your mind

Well, actually Francis Collins, among notable scientists in America, is the rare exception. A recent survey of members of the National Academy of Sciences (which is our equivalent of the Royal Society) found that fewer than 10 per cent believe in God or an afterlife – and the figure is even lower for biologists.²A 1998 survey of members of the NAS found that only 7% believed in God. Of the biologists, 5.5% believed in God and 7.1% in an afterlife, whereas 65.2% and 69% respectively did not. Belief was most prevalent among the mathematicians: 14.3% and 15% respectively (see nature.com/articles/28478). Remarkably few.

I think we recognise that you can be a very good scientist, you can even be a great scientist – remember [Isaac] Newton – and remain a religious believer; but in the present day, when so much is known about the origin of humanity and the biological basis of our behaviour, you would need to compartmentalise your mind. I don’t think that you could work in evolutionary biology as I do and be a religious believer. You would have to choose projects that are outside the domain of belief.

There are scientists such as Simon Conway Morris³Professor of evolutionary paleobiology at Cambridge, and the author of The Crucible of Creation (OUP, 1998) who would argue that God so designed the mechanism of the universe that it would lead inevitably to the evolution of intelligent creatures that could know him.

Well, what that does is immediately drive the conversation all the way back to astrophysics and the so-called anthropic principle. That’s one way to make some kind of an accommodation – I can’t think of any other way; I would do it if I could, but I can’t – but it moves God pretty far away from the concerns of humanity.

I’d like to say, too, that scientists have an open mind – that’s what defines science, in part – but it’s also a sceptical mind, which means that we demand more and more proof as the subject becomes more and more important. It’s been said, very rightly, that a supernatural intervention would be such an extraordinary event that belief in it would require extraordinary proof. If anyone could show conclusively that there was such a thing as the operation of supernatural intelligence and its direct influence on the real world as we understand it, it would be the greatest career-maker in history!

I think there’s a widespread feeling (if I could just expatiate for a moment) that there is a permanent hostility between science and religious belief. There is not. Good science always holds itself open to any possibility, and even where physical laws and the ubiquity of natural selection seem to have been thoroughly established, still we think through all these ideas with an open mind.

You have notably proved willing to change your mind, but often we see scientists fighting hard to defend their own theories. It all seems a long way sometimes from Karl Popper’s principle that, having come up with a hypothesis, one should do all one can to falsify it and should accept it only when all such attempts have failed.

Well, those two attitudes would be the extremes. What I want to do is to find a better theory if one exists. So, in the case of sociobiology,⁴The systematic study of the biological basis of all forms of social behaviour in all kinds of organisms, including humans I originally thought, for example, back in the Seventies that there was strong evidence for kin selection as an explanation of the origin of altruism,⁵Kin selection theory would suggest that a gene that encouraged an individual to act in the interests of her/his relatives even at her/his own expense might prosper because it helped those relatives to survive and they possessed and passed on the same gene. but as time went on I (and others) found that in general it was not working very well, and so we gradually developed a theory that worked a lot better.

Which is multi-level selection. 

Yes, which says that in the evolution of social systems, especially advanced systems where you have tight, well-organised groups, selection is operating at two levels. Darwin himself proposed group selection in The Ascent of Man – he had a pretty good insight into what was really happening, which is that within the group individuals compete with one another – for status, for mates and so on – but at the same time the group is competing with other groups. Defeating other groups is a very powerful force. You don’t have to defeat them in war; it can just be a simple matter of using the environment more thoroughly and building up a bigger population.

The effect of this you would expect is that within groups behaviour evolves that could be called ‘selfish’ – it favours individuals within the group, which often is at the expense of the group – whereas competition between groups feeds on those gene-determined traits that actually [promote] altruism within the group. An awful lot of this fits the known cases of advanced social behaviour in the social insects – and, in my judgement, it also fits humanity. That is, in essence, what all the recent controversy has been about.⁶See especially bit.ly/LulZrs (including the comments).

In The Social Conquest of Earth,⁷Published by W W Norton & Co in May 2012 I showed that there are only about two dozen known cases throughout the entire history of life of [the development of] advanced social behaviour based upon what you would call ‘altruism’ in the division of labour in producing and raising young. So, a rare event. And then I showed that of those we can track genetically – that is, really see where they came from, in what circumstances they became social – without exception they came from species that mated as solitary individuals up to a particular adaptation: the building of a defended nest, and foraging away from that nest to bring food home to raise the young.

And I then fitted it to the human story, as best we understand it. I went through the paleontological evidence very carefully and it seems (to oversimplify the matter a bit) that that is what happened in humans, too. About two million years ago, Homo habilis began to shift heavily to meat and it’s very likely that they also then started occupying campsites. And all their immediate descendants – certainly Homo erectus – not only were hunting or scavenging and bringing in meat but were also certainly in campsites – and by that time were able to control fire. That was the big turning-point in the origins of humanity.

So, altruistic behaviour emerges out of the benefit that comes from clustering together in defended nests?

Exactly. It creates a social environment.

Chimpanzees, our close cousins, get only 3 per cent of their calories from meat, whereas humans, when you average out all the existing hunter-gatherer societies, get 30 per cent. And when you come together – which is the best arrangement when you’re gathering meat, which is an extremely rich resource but is hard to get – [and] you’re not wandering around like the chimps looking for fruit trees, tubers and so on, in bands but breaking up and not living in the same spot for a long time, then you can see what most likely happened.

And here I’ve brought in the social psychologists. Their research emphasises the amazing intensity of the interest we have in other people – we read intentions like geniuses. And that kind of social intelligence is not there in the chimpanzees at all. And this, I think, is what you would expect to have going on from Homo habilis times. Lots of what we think of as basic human nature, which includes group formation and competition and the intense interest people have in each other, within groups and between groups, is what happened next in evolution. And when you have that, you can explain the almost exponential increase in brain size from Habilis to Erectus. The greatest growth was in the cortex and had to do with memory. Our memory is exquisitely good when it has to do with other humans and our relations with each other.

Nothing is more important to think about, in science and in our daily reflection, than the questions: Where do we come from, and what are we? I find it amazing so little serious attention is given to them

So, I think we’re onto something there. In general, I would say that increasingly we can understand the story of where humanity came from and it is consistent with biological principles.

Some of the language you use in The Social Conquest seems to imply design – you talk about ‘hands and feet built for grasping’, for example, and a pelvis ‘reformed … to support the viscera’. Do you have any sympathy with people who look at such progressive developments and think they can see a designer behind it all?

No, I haven’t, to tell you the truth. I do say in the book: Well, maybe there’s a God or a supernatural divine force that guided this evolution – that’s always something we could think about. But if our view of evolution is correct – and I think it’s coming pretty close to a certainty that the broad idea of evolution, with mutation generating variation on which natural selection acts, is correct – then God would have to engineer random mutations, and changes in the environment such as sunspots and so on, many of which are extremely complex and due (to the human mind, anyway) to chance events. All of that would have to be prescribed.

And the amount of prescription required would be so great that it would preclude any kind of free will?

That’s a good way of putting it. You know, either God would have to be almost infinitely remote from what is actually happening – the original designer of the physical laws who then dropped out, maybe to observe from a distance – or you’d have to go to the other extreme and he’s guiding evolution and everything is determined by him. And neither is very appealing, I think, to either scientists or the religious faithful.

Even so, having written God out as unnecessary, at the end of the book you do seem to allow that he might exist after all. Do you find yourself still leaving space for him?

Actually, yes. I couldn’t believe personally in a God but I see how deeply faith in the divine is rooted in my own people and how much it is part of American culture, and all the services that religious organisations perform. I think that eventually we will evolve toward where Europe is right now – you know, a steady progression toward secularism – but we could not make that leap in a generation or two in America.

As for turning a scientific view of reality, what really happened and what we really are – which is what I’m all about – into a weapon to wipe out religion, it doesn’t make a lot of sense to me. I’m simply not a militant atheist, one who thinks other people should believe the way I do, and I don’t find that people respond well to being insulted and threatened.

What do you want this book to achieve?

Now, that’s interesting. I would say I wanted to report the best that science has to offer us in self-understanding, and I would like to see this become part of the public discourse. If I could stir things up… Nothing is more important to think about, in science and just in our daily reflection, than the origin and meaning of humanity, the questions I ask: Where do we come from, and what are we? I find it amazing that so little serious attention is given to them. There are not many scientists around who ask those questions, and there are very few people who would even think about thinking about them.

I think that future generations will say that what we did was an evil – and they will be able to find villains, all over the place

One of your other passions has been the environment and the effect that humans are having on it…

I was so fascinated by nature from my early boyhood that it was natural that I would grow up as a strong conservationist, and that was intensified by the fact that I ended up studying biodiversity – in fact, I helped to introduce the very word ‘biodiversity’. It seemed to me that, whether you believe in God or not, to save all the life we can, the diversity of it, should be a moral imperative for both the religious and the non-religious.

That’s why I published my book The Creation,⁸The Creation: An appeal to save life on Earth (W W Norton & Co, 2006) which in part is addressed to the religious and says to them: Let’s stop fighting over other issues and combine – science and religion, the two most powerful forces on the globe – on one thing we both consider a moral imperative (or I sure hope you do, I would say to them) and save what you call ‘creation’ and I call ‘global biodiversity’.

In the past you have said that you don’t think it would be wrong to speak of our species as in some sense evil – at least now that we know the damage we are doing…

I’d put it that way. I think that future generations will say that what we did was an evil – and they will be able to find villains, too, all over the place: those who made decisions, on every continent, to go ahead with destroying a large part of life unnecessarily.

We seem to be slowly applying the brake, but we haven’t made the protection of the rest of life – I would put it that strongly – an important focus of our lives, and we certainly have not made it a moral imperative that would unite global action.

Why is this such a difficult issue in the United States? Many people there are reluctant even to acknowledge the reality of the damage we are doing to the earth.

And half of the American people deny evolution – and some of the Republican far-right is even taking an anti-science posture.

Why are we passing the razor across our throats? I think it’s because the United States was so recently an authentic frontier country. As recently as a century ago, most Americans were rural, scattered in small pioneer settlements that were starting to congeal into villages and small towns – and these were the great-grandparents of people living today. You know, when I was a boy I once met a veteran of the Civil War! Anyway, these people had to find something that could unite their local communities. They didn’t have what Europeans had – cities, cathedrals, traditions of government that were based on alliances of religion and the secular; they had only one thing that they could turn to as an absolute authority and that was the Holy Bible.

And that is where fundamentalism came from. You doubt things in the Bible, you preach evolution as an explanation of where we came from in the first place, you are not just messing with religious belief – they don’t say it, but this is what they really feel – you are messing with my identity, what makes me the person I am and what gives me strength (as it has done since the pioneer days).

Even a very simple ecosystem is beyond anything we can hope to imitate. How can we justify, in one lifetime, recklessly throwing it all away?

And the reluctance to accept the evidence on climate change fits into that picture as well?

Yes. I think Americans still have this religious feeling that the earth is theirs to take. In other words: Who are you to tell us we can’t cut down our forests or remove our mountaintops for the coal? This is God’s will that we be using the earth for the good of humanity.

And you then have to explain to them, as I tried to do in my book with only minor effect, that in the long term you really would not be doing God’s will.

If the biosphere, and indeed the whole universe, merely happens to exist and is purposeless, why does it matter if some species are eradicated?

That’s a question which I’ve been fighting for these many decades, spelling out why we should care. It’s just manifest that it’s the diversity which we’re destroying that gives us environmental stability, that gives us – well, one account has it, free ecological services (if you want to be economic) in terms of creating soil, purifying water and on and on, which if they were converted to dollars are equal to the total world domestic product.

And then there are all the things that we will learn and that future generations can enjoy for as long as we are on this earth that come from the co-existence of the many species of plants and animals and even micro-organisms that have been generated by evolution. I’m always awestruck by what human art and the human imagination can create, but it is nothing compared with the wonder and potential for surprise of a single ecosystem and its structures and operations and processes, which are the product, bear in mind, of over three billion years of evolution.

We know now that the complexity of even a very simple ecosystem – a pond or a marsh – is beyond anything that we can hope to imitate. How can we justify, in one lifetime, recklessly throwing it all away?

A slightly longer version of this interview was  published in the November 2012 issue of Third Way. To make sure you hear of future interviews in this series, follow High Profiles on Facebook or Twitter or join our mailing list.