The End of the Journey

One of the original purposes of this blog was to find areas of understanding and overlap between the study of biology and the study of human actions and society. One of my big ideas was to draw parallels between the ways different societies are run and the way groups form in nature. Concentrating on the evolution of multicellular bodies, I began looking at intra-organismal policing mechanisms and different ways of ensuring harmony within the body. I then sought to use this as a lens with which to view our own society, asking myself where I saw similar themes- what was different and what was decidedly the same.

Along the way there were roadblocks and frustrations. Despite seeing a veritable glut of similarities and links between these two fields, the potential for abuse was too great. As I noted in my post about the faux pas of social science, biology is all too often applied superficially to explain things we see in society. The most egregious mistakes were often cases of using biology to back a political agenda, citing some trivial fact and claiming biology as proof of an entirely unrelated concept (eg see David Brooks' article). Yet, the misuse of biology to describe society manifested itself in subtler forms as well.

Stimulated by my work in multicellularity, I soon began looking at the evolutionary concept of levels of selection, seeking to understand the conflicts which can occur between individuals and wholes in the formation of a group. In biology, levels-of-selection ways of thinking are crucial to dispelling myths about group selection and understanding the conflicts and policing mechanisms which occur in evolutionary transitions, like the advent of multicellularity. In the spirit of my original goals, I soon tried to apply such thinking to human society, but in doing so ignored a very important, fundamental difference. While nested groupings in nature, such as the organization of genes into chromosomes, chromosomes into nuclei, and cells into bodies, are all necessarily products of evolution, the human societies which we see today are not. Evolution undoubtedly played a role in crafting the societies which have emerged, played out through the evolution of our very brains and the emotions like empathy and morality it produces. Yet, it is not reasonable to look at different types of societies, whether they be conceptions of social justice or systems of free market democracy, and to look at how evolution has shaped them. For this, we have the study of memetics, which I believe will boom in coming years as neuroscience advances and we begin to understand the proximate mechanisms of memory and learning.

Cells do not simply decide to organize themselves into bodies. A wide range of literature in the past fifteen years has begun to address this issue, and there are several main problems to be overcome in the construction of a multicellular body. Not all cells in a body will pass their genes to the next generation. Think of your arm cells for example. What makes them satisfied with your gonads getting exclusive access to the next generation? In the case of animals, this problem has been solved largely through reduction of intra-organismal variation- your arm is okay with your gonads doing all of the long-term reproducing because the genes in your arm and your gonads are ideally identical. In other taxonomic groups besides animals (yes, many other groups exist, like slime molds, chromalveolates and fungi to superficially name a few) this problem has been remedied in very different ways. For example, slime molds are made up of many multicellular individuals aggregating into slithering sluglike forms (they actually do look like slugs, it's very cool). If two of these slugs cross paths, they can mix and reform, with the two emerging slugs having possibly traded segments, or else even have 'stolen' parts from one another. These slime molds really challenge our notions of what it means to be an individual, and the policing mechanisms which have arisen in these slugs differ greatly from those found in our own bodies.

But to return to human societies, people can simply decide to form social groups, there is no conclusive evidence to date that free market democracy is a direct result of evolutionary transitions involving natural selection. As such, these societies do not necessarily operate on the same principles as biological groupings and are not always subject to the same constraints. So how is it anything but glaringly superficial to equate human society with cell society? The parallels between our communities and those found in other parts of nature are truly great, but we must be diligent not to make comparisons where there truly are none, and not to get carried away in our thought experiments.

If anything, maybe it will be useful to recognize precisely this point, that human society does not necessarily need to adhere to the rules of biology. Animal populations which exceed their carrying capacity will crash, and for every animal over this capacity the population will crash by roughly twice this number. However, people (I hope) don't need natural selection to keep our populations in check. We don't need to wait until human populations naturally stabilize (as suggested recently by Mark Koyama) in order to realize that we face an impending problem. Culture gives us the ability to cut off these problems before nature makes us learn the hard way.

Economic growth has undoubtedly led to prosperity, allowing the poor to access a growing array of commodities and raising the living standard so that the lower economic classes of society can live far better lives than Charlemagne ever aspired to. But are there natural limits to this growth, and if not, is there reason to impose them? If there do in the end exist meaningful ways of finding overlap between science and the study of economy and society, then perhaps this is a direction worth venturing towards. If not, then at least the semester-long search for such consilience has been eye opening for one young scholar at Brown University.