No, Richard Dawkins, eugenics would not work in humans like it does in cows and pigs

For all that science has enriched society through the curing of diseases, the prevention of hunger, the making of smartphones, it has also birthed eugenics, the idea that refuses to die. On Sunday morning, celebrated geneticist Richard Dawkins woke bright and early to tweet about the efficacy of eugenics:

And, of course, Dawkins, being a rational scientist in a long tradition of rational scientists, is famously selective of facts over ideology. Except it’s not so simple. Leaving aside the laughably naïve idea that scientists working in any field, let alone the highly emotive, politically riven field of human genetics, are able to somehow shake off the socially-determined values of their time, class, status, gender, and politics to be fully objective about “facts”, eugenics still wouldn’t “work” for humans.

This is because, in a very fundamental way, humans are not like other animals. Humans emerged, like every other life form, through the process of biological evolution. Species change over time because randomly occurring genetic differences accumulate within populations over generations. Organisms whose genes make them more successful in their environment are more likely to survive and reproduce, thus passing their genes to subsequent generations. In this way, biology adapts to environmental pressures, and species have gradually evolved to exploit every habitat on earth.

Our intelligent, social ancestors also evolved adaptations to survive in their environment, and one of these adaptations was our extraordinary culture. Human cumulative culture ratchets up in complexity and diversity over generations to generate ever more efficient solutions to life’s challenges. Instead of our evolution being driven solely by changes to environment and genes, human culture plays a steering role. Cultural evolution operates at the group level – traits, behaviours, technologies, and so on, are selected and transmitted by society. Although humans are genetically very similar – there is less genetic difference between two human populations than there is between two chimp populations – culturally we have diversified.

Unlike other animals, we have pretty poor innate survival skills. Humans rely entirely on culturally inherited adaptations, not genetic ones, to survive in our specific physical and social environment. We are immersed from birth in a cultural developing bath of particular behaviours, ideas, values, and technologies that have been selected over generations by our society. The makeup of this cultural developing bath is itself socially constructed and inherited, so that the traits we learn and how we learn them depends on our position and connectivity within the social network. For instance, in a patriarchal society, the cultural developing bath equips boys to enjoy more powerful roles, and to be perceived (and perceive themselves) as more intelligent and capable than women.

Humans are a species defined by culture, and culture is wholly socially dependent. Our success as an individual relies on our position within society, and our unique cultural developing bath – very little of this has anything to do with our genes. Even for a trait like height, which is 80 percent heritable, there are big differences between people living in poor countries and those with good nutrition. People who grew up during war and famine are often shorter than their well-fed children. Indian girls and non-firstborn boys are on average stunted because a cultural preference means the firstborn boy gets the best nutrition and grows the tallest.

Human culture is so powerful that it not only shapes us as individuals, but has remade the natural world too. As Dawkins points out, cows, pigs, dogs and roses are among the socially contrived inventions humans have made over the past millennia – none exists naturally. We have made these species to fulfil a human, culturally determined requirement, whether that is to produce greater muscle mass, or red petals. From that very narrowly defined human perspective, our interventions have worked. From the perspective of the domesticated creatures, however, they have arguably not worked – consider that many are now entirely dependent on humans to survive, breed, give birth. Dogs that struggle to breathe, with hips that spontaneously dislocate, that need caesareans to give birth; pigs so fat they overheat, and so on.

Leaving aside the problematic definition of “works”, and presuming Dawkins means eugenics would work by increasing the prevalence of a trait within the population: it still wouldn’t work for humans outside of a very narrow subset of single gene conditions. Eugenics is touted as a way to remove undesirable conditions (and often people) from society, while boosting desirable ones. Undesirable conditions range from criminality and mental illness to physical disabilities; desirable ones are intelligence, beauty, including preferred skin colours and features. Of course, whether you consider a trait to be desirable or undesirable depends on your own cultural developing bath.

Leaving this, too, aside, at its least unpalatable, the gene-editing and gene-discriminating techniques favoured by eugenicists may be used in early stage pregnancies to prevent life-limiting conditions. For instance, a chromosomal disorder, or Huntington disease, in which a single gene is involved, have the potential to be eliminated.

However, for traits such as intelligence or sporting prowess, eugenics won’t work in humans. This is partly because multiple genetic factors are involved, (which are not, despite persistent assertions to the contrary, handily associated with other traits such as the multiple genes coding for skin colour or enzyme production). More importantly, though, eugenics won’t work in humans, because we are not set in stone by a few genes but made in a cultural developing bath. Whether we can run fast is largely determined by cultural developing bath factors, such as what and how much we eat, whether running fast is encouraged and how often we do it.

Our species is as defined by culture as by genes – this is as true for how we rank and define intelligence as it is for criminality. We make ourselves socially, continually through a human evolutionary triad of genes, environmental and culture that feedback on each other. And we rely for our success as a species, and as individuals, on the broad diversity of our genes and cultures that equips our society’s toolbox with the resources to meet life’s challenges. It is this extraordinary diversity and complexity that means eugenics couldn’t “work” in humans. It is the same cultural-genetic makeup that drives us to “deplore eugenics on ideological, political, moral grounds”.

This and more is discussed in greater detail in my book TRANSECENDENCE: How humans evolved through fire, language, beauty and time, also published in America.