Darwinism continues to make inroads into what we believe about ourselves. Haydn Shaughnessy reports
In the 1970s a scientist wrote a book that set out one of those propositions the average reader hopes is not true. It became surprisingly popular, enough to change the way we think about the physical world. The year 2005 will be the one when those ideas, roughly speaking Darwinism, and new evidence about the effects of evolution on human behaviour, will come of age.
Darwinism will move on from its monkey forebear clichés in the public mind and be accepted as a system of thought capable of influencing a range of important policies.
The book, by the way, was Richard Dawkin's The Selfish Gene. Though flawed, it became one of the most successful and popular science books in memory.
Our bodies, says Dawkins, and the bacteria and viruses that we carry, are part of a global battle for survival at the genetic level. We humans therefore live, in part, as vehicles for genes that do not belong to us or play no functional role in our bodies. Genes, the building blocks of life, can also be independent.
What Dawkins had to say then, and continues to repeat, is that in the genetic war those of us with personalities, brainpower and opinions are irrelevant.
I think there are large measures of junk in Dawkin's work but it set two precedents.
Today the reading public turns to science writers for their information, their sense of revelation. And today we recognise the high degree to which our holistic wellbeing results from battles in the genetic world.
Anathema to the Church, Darwinism continues to make steady inroads into what we believe about ourselves. One Darwinist, for example, the epidemiologist Paul Ewald, author of Plague Time, has established that many of the illnesses that cripple us - cancer being a prime example - are caused by viruses that continuously mutate. That's why cancer continues to elude medicine's silver bullets.
Cancer as a virus? The idea runs counter to what we thought we knew - that cancer is caused by genetic pre-disposition or environmental factors like diet. But Ewald points out: "In the few years since I wrote Plague Time, a consensus has emerged that [for example] human papillomaviruses are an important cause of head and neck cancers, such as cancer of the tonsils. This is eye-opening for many people because the papillomaviruses that are responsible are the ones that also cause cervical cancer and probably penile cancer."
Ewald's proposition is that relaxed sexual mores probably mean that people are getting head and neck cancers from a virus transmitted by oral sex, a deeply disturbing and heretical proposition but one with a compelling logic.
Over the past 10 years, Ewald's arguments have found wider acceptance. Recently, Australian researchers isolated a mouse virus that is probably implicated in breast cancer, an idea rejected by orthodox oncology for the past decade. Schizophrenia has demonstrable pathogenic origins.
Degenerative illness is the result of a pathogenic war where bacteria and viruses mutate beyond the ability of humans to mount an immune or genetic defence. Their adaptation is superior to the adaptive processes of human bodies.
Ewald and Dawkins are part of a group of Darwinists who have spent the past 20 years studying how we talk and write, how we fall ill, how we eat, how we behave with genetic kin in families, all from the point of view of natural selection, genetic mutation and behavioural adaptation.
Helena Cronin is a philosopher who has operated as a hub for this particular strand of thinking, a scientific approach to human behaviour that is capable of displacing many of the prejudices of modern politics.
"Any area of policy that makes assumptions about human behaviour should take into account how those polices relate to our adapted nature," she says. For example, we are "natural co-operators" with a defined sense of fairness, yet politicians operate on the presumption that people are naturally aggressive competitors with a jungle instinct.
Our sense of fairness was born out of two types of wealth enjoyed by pre-modern humans, Cronin explains. One, wealth earned by gathering food; two, an occasional windfall - wealth gained by hard work coupled to good fortune. Our adapted disposition is to share the latter. That's what allowed us to smooth the troughs and peaks of wealth. This has important implications for tax and welfare policies and for policies that decide the use of public space.
If this sounds a little abstract, then Loren Cordain, one of the world's leading experts on human diet, has quite pragmatic recommendations. The author of The Paleo Diet Book, Cordain has developed a scientific basis for the optimum human diet by studying evidence from human evolution.
He argues we have to look at what our bodies require genetically if we are to understand how to avoid degenerative illnesses. That means using building blocks that are 40,000 years old.
"Hunter gatherers relished the fatty parts of the carcass," says Cordain of ancient meat-eating humans , "i.e. marrow, brains, eyes, tongue, mesenteric fat, perinephral fat etc." But he goes on to explain that in the wild, animals have virtually no fat for six to eight months of the year and the fat of the animal that people lusted after was largely made up of polyunsaturated and mono-unsaturated fats.
So, although a chef will tell you fat is what makes meat taste good, our genetic disposition is towards craving specific fats, from offal. Our disposition towards saturated fats was minimal except for a brief period in the summer when animals may have overeaten.
Darwinism is about to enjoy an upsurge because it addresses problems like these, problems that vex us - how to eat, how to re-evoke civil values, what to do about serious health problems. And it does so a step beyond prejudice. Of course, as Ewald points out, "humans evolved to compete for status, not to be objective scientists".
His own view is that many scientists on the opposing side will have to retire before the new Darwinists get their points of view across. But it is only a matter of time before the route to health will be judged by a new orthodoxy.
What do Darwinists believe?
We are what we were 40,000 years ago when natural selection created us.
Humans function in ways that are predetermined by their genetic make-up and do not learn everything they know. They are born to a certain extent pre-programmed.
Politics should use the natural human condition as a basis for policies on family, employment policy, criminal justice and health.
Humans are basically co-operative and have built an elaborate sense of what is fair.
There are universal characteristics, one of which is that our minds react in a stone age way - for example, there is evidence that height is a good criterion for predicting successful politicians.
Families are the only viable unit for human reproduction and social stability.
Anti-social behaviour is often the result of adaptations, of people making rational decisions from an evolutionary perspective - teen pregnancies are aevolutionary response to a bleak future.