Monday, February 06, 2012

Thoughts on the Evolution of Social Complexity in Humans

Whenever I engage in discussions with people who object to evolutionary explanations of human behavior, I discover the same underlying misconceptions of evolution.

First, we need to realize that the presence of a trait does not mean it was necessarily selected for or 100% adaptive. Evolution is not teleological. You can have traits that are adaptive, traits that are neutral, and even traits that are slightly maladaptive, so long as it is not overly harmful. Those of the latter two kinds can act as sort of “preadaptations” for different future conditions, if they end up being neutral in the original environment, but adaptive in a later one. Also, one can have the evolution of a trait that is both adaptive and maladaptive. The dropping of the larynx, for example, is necessary for speech – but dropping it also makes human susceptible to choking. The latter is clearly maladaptive, especially since it does kill some people, but it is also clear that language was so beneficial, that it over-rode the slightly maladaptive element to the adaptation.

Another example of this is our having adapted a hypersensitivity to the presence of intentionality. Those who were able to detect intention – which is to say, those able to see an orderer behind any order – were more likely to survive in a world full of other tribes who were more likely to spear first, ask questions later. It was better to mistakenly see intention than to miss it, so those who overapplied the presence of intention were more likely to survive. Combine that with the unifying elements of ritual and storytelling, and you have religion. This too is adaptive insofar as it enhances social cohesion. Hypersensitivity to intentionality only becomes maladaptive if, once people reject religion, they continue to believe that for there to be order there must be an orderer, and they then go on to adopt socialist ideals. This indeed, was Marx’s objection to capitalism, that it was chaotic. He could not even see the order in it, though it is an exemplary example of self-organization and the patterns associated with such processes.

This sets us up to deal with the specific objection, which is that it makes no sense for people to be so social that they will accept others from other tribes into their own. As it turns out, Darwin himself dealt with this issue – and dealt with it in the way that most evolutionary moral theorists have come around to themselves – which is the “expanding tribe” theory of increasing moral behavior. Insofar as one is dealing with related individuals, altruism is pretty easy to explain. But how do you know who is related to you? This is easy enough if you are a member of a tribe – everyone in the tribe is your relative. However, chimpanzee females leave their troop for other troops once they reach sexual maturity. Humans do the same thing. Both are driven by the Westermarck effect – an evolutionary adaptation that reduces significantly incest. One of the results is that other troops/tribes end up having your relatives in them. For chimpanzees, this is not an issue – if you are a member of another troop, too bad for you. However, bonobos do not go to war with each other. Humans are about halfway in between in behavior. This, in combination with the presence of language, which can act as a marker for relatedness, can tie together a number of tribes. Especially those tribes that used to be united, but divided because of environmental conditions. Religion can also act as a social marker in this sense. Thus, those who speak the same language and practice the same religion could remain closely connected. This was strengthened by trade between such tribes. Bonobos engage in a primitive kind of trading, but human trade is much more complex. It is one of the main drivers of social cohesion, and can even override significant social differences, such as language and religion. In a species which over-applies behaviors, it should not be surprising to find trade being extended to even non-related tribes over time.

There are two things that are distinct to humans: language and trade. I believe both can be explained quite handily using evolutionary theory. One would have to argue that both language and trade are a divine dispensation – that God gave us both language and market activity – as both are sufficient to explain the expanding tribe theory. Social signaling is sufficient – if we can communicate with others we are members of the same expanded tribe, then we are accepted.

I do not believe any of this necessarily denies the existence of God. I would have to wonder at the kind of God who could not create a universe that did not need his constant intervention for things to go right. If you want to believe in that pathetic little moron, by all means do so -- it's just not a God for me. Further, it may be that we are all evolving toward God, emerging toward the ultimate emergence.

And that brings me to the problem of the concept of emergence. Too many people are still rejecting this concept, acting as though all scientific explanation is necessarily reductionist. That is an impoverished science. And it misses half the universe -- the evolving, complexifying half. What is the relation, then between the brain and mind (which is really what I've been talking about, above)? Well, to amino acids, the cell is an emergent phenomenon. And it is, in relation to its constituent biomolecules. It has emergent behaviors, and the existence of the cell affects the kinds of chemical activities that take place, when and where they take place, to a certain degree. Similarly, the (inter)actions of the neurons in the embodied brain in their minding processes give rise to the mind, an emergent process. This mental order in turn is able to affect the underlying neural activity to a certain degree. The economy, for example, is a complex emergent process created by the interactions of a variety of embodied minds. The mind is a complex emergent process created by the interactions of a variety of neurons. A cell is a complex emergent process created by the interactions of a variety of biomolecules. Atoms and their ability to engage in chemical reactions are complex emergent processes created by the interactions of a variety of subatomic particle-waves. You can call this reductionist if you want, but if you only engage in reductionism, and ignore emergent properties, you won’t have the foggiest idea what is really going on. In this sense, Darwinian evolution is not reductionist, and nobody is reducing a thing by invoking it as a proper explanation of biological activities.
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