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The Extent of the Extended Phenotype

Emmet Feerick explores the implications of an evolutionary psychological idea for our lives.

When you look out the window, and see a bird flying off to some other place, do you ever get the sense that its life must be pretty meaningless?

I mean, it spends all its time flying around in search of mates and food. That’s the purpose of its existence. That’s all it knows and that’s all it’s here for. When it’s not doing those things, it’s sleeping in its nest. And it sleeps only so it can rebuild its energy to do more mating and eating. That’s the whole ‘point’ of a bird’s life.

Yet when you look out your window at the human world, what do you see? One definite thing is buildings; lots of them. That’s an obvious sign that there is something similar between us and the animal world. In a way, you could view our buildings simply as more complicated bird nests. We make them so we can be warm and comfortable, and so that we have somewhere to sleep. You could look at beaver dams and fox dens in the same way.

From a biological perspective, it makes sense to say that nests, damns, homes, and dens are created by genes. It goes without saying that the heart, lungs, skull, and other body parts are also made by genes. What separates these things, then? Why can’t we say that our phenotype – the physical manifestation of our genes – consists of skulls, hearts, and houses? Is it only because that houses are outside of the body? After all, the job of a gene is to replicate itself. It has to keep the organism which it belongs to alive in order to do this. How it goes about doing this is surely worthy of the word ‘phenotype’.


It makes sense to say that nests, damns, homes, and dens are created by genes.

In this view, a bird nest or a beaver dam, or indeed, a house, is just as much as part of an animal’s phenotype as its skull, or its fur, or its circulatory system. These are simply attempts by the gene to modify either the organism, or the organism’s environment, in order so that the gene survives. The biologist Richard Dawkins coined the term “extended phenotype” to describe this phenomenon in his 1982 book, The Extended Phenotype. An extended phenotype is simply a physical manifestation of a gene’s survival efforts which extends beyond the bounds of the organism itself.

It is easy to see, for example, how a house could be seen as an extended phenotype. Its warmth aids our survival by ensuring that our bodies expend less energy on temperature regulation; its roof shelters us from the elements; and its walls protect us from other primates and animals who might harm us. Houses, then, are just high-tech bird nests. Going back to the window, though, and we see that the world of humans consists of many more buildings than just houses. We use buildings to get an education, to work, and to exercise. We use them to bank, to send letters, and generally to take part in the massive, complex global society that is unique to our species. This is our lives. How different this is from the lives of the birds! We have meaning and direction and purpose. It seems that there is some meaning to all of this complexity that is of a whole different order than the merely survival-based adaptations of the “lower” animals. Where they build dams and nests, we build communications networks and global financial systems.


An extended phenotype is simply a physical manifestation of a gene’s survival efforts which extends beyond the bounds of the organism itself.

From the viewpoint of our genes, however, is any of this really different from building houses? What drives our intuition that there is a real, qualitative difference between structures like houses, and infrastructures like the financial system? The answer seems to be quite straightforward – distance. The end goal of a gene is to get itself passed on to the next generation. It’s easy to see how houses facilitate this. It’s less easy to see how banks facilitate it. In the case of banks, the starting place (the physical building of a bank) is quite distant from the end place (the survival of human organisms). And yet this is undeniably their ultimate purpose. We use banks to keep our money safe. Money is what we use to buy things, from food and cars, to, well, houses.

On the view of the extended phenotype, the goal of the entire global financial system is to maximise the survival chances of large numbers of people. Our genes have built brains which have built financial systems which, at least in principle, maximise wealth. Where they fail at this (and they do, with some degree of regularity, it must be admitted), this can be attributed to the complex nature of the systems themselves. With all of their moving parts and interactions, financial systems take on a life of their own, which is not reducible to the genes which created them. This is to be expected – even comparatively simple systems, like the weather, cannot be predicted with reference to individual air or water molecules. All that needs to be said to defend the extended phenotype’s case, however, is that its overall effects are superior to that of those if it had not existed to begin with. Try and imagine a world without banks, and you’ll quickly see that they have been one of our genes’ most successful projects.

The same can be said of legal systems, whose goal is to maintain social order, and ensure the upholding of individuals’ rights. Again, not too many steps are required to work out how these things aid our survival. It makes sense, then, to think of the banks and the law as tremendously large and complex life support systems. They are like our hearts and skulls, in that their ultimate purpose is to maximise our chances of survival, and thus our genes’ chances of propagation into the future. We only fail to see the connection here due to the sheer distance between these systems and the end genetic goal of survival. Where skulls and hearts are directly connected to genes, the financial and legal systems are connected to genes through the conduit of psychology. This psychology gives rise to the behaviours which bring these complex systems into existence, and which in turn aid the survival of the organism. From this perspective, all roads lead to the genes.


From this perspective, all roads lead to the genes.

There are some areas of life that do not seem amenable to this kind of explanation, however. How would art fit into the picture, here? It doesn’t have any obvious genetic purpose. Additionally, you could argue that the complexity of our brains enables us to experience depths of emotion and thought that are not accessible to other animals. To the extent that this increased intensity and complexity have intrinsic worth, our lives are more meaningful than the lives of seagulls. Despite these objections, the view of the extended phenotype remains a fresh perspective from which to view the world, and within which to place our own actions and motivations. So, think of that the next time you pity a seagull for the banality of its life. We’re really doing the same thing, at heart.