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Applying Darwin Beyond the Physical

selias's picture

In "On The Origin of Species", Darwin presents what he has observed occurring in nature and writes about the theory he has come up with from his observations - the theory of evolution.  In his concluding paragraph, he sums up his story of evolution by saying that all things living today "have all been produced by laws acting around us. These laws...being Growth with Reproduction...Variability...and as a consequence to Natural Selection...Thus, from the war of nature, from famine and death, the most exalted object which we are capable of conceiving, namely, the production of the higher animals, directly follows." (2) What Darwin discusses, then, are the patterns and laws that govern the evolution of animals in a physiological representation of variation.

One of the discussions we had in class, however, made me think of what the larger implications of Darwin's story of evolution could be beyond the physical traits that can be observed.  One day the topic of social norms came out as a prospective discussion topic but it was quickly skipped over.  This made me wonder, how are cultural traditions and social norms transmitted and spread?  Obviously some of these questions have scientific answers, but what I am looking in to is whether or not there is a certain reason that some cultural traditions persist and others do not, and especially whether or not the Darwinian story of evolution can be applied to this situation as well.

A first major distinction between evolution of certain characteristics and evolution of certain physical traits is that the evolution of the traits is definitely genetically based.  For behavior, however, there is more of a debate about whether or not genes are what determine behavior.  Many behavioral disorders are associated with a certain gene either being damaged or not present; for example, those who have Williams Syndrome, a neurodevelopment disorder that in turn affects behavior, are most likely missing genes 25 to 28 on the seventh chromosome (1).  These are examples of variations as Darwin defined them, differences between individuals of one species that can either lead to an individual's increased ability to survive in the conditions it lives in or will be a detriment to the individual.  So it is clear that genes can influence behavior; the main question is the extent to which they are solely responsible for the behaviors or whether it is the environmental situation they grow up in that determines the behavior of an individual.  

The existence of instincts also provides evidence that this type of behavior is developed and passed down through generations in a Darwinian evolutionary model.  In fact Darwin himself wrote about instincts, indicating that he too believed that the instincts that are shared by one species are widespread because they have been selected through evolution. "To my imagination it is far more satisfactory to look at such instincts...not as specially endowed or created instincts, but as small consequences of all organic beings, namely, multiply, vary, let the strongest live and the weakest die." (2) The evidence of widespread species behavior, such as the ant's instinct to create slaves or a bird's instinct to kick foster brothers out of the nest, as Darwin observed, show evidence that certain behaviors can be selected through the evolutionary process and become the norm across the species.


So it appears that Darwinian evolution can be applied to behavior patterns, to some extent.  What I want to know is, what about cultural traditions in human populations that do not have any genetic basis?  These are things that are commonly accepted as the status quo as normal behaviors, but are not followed by all. I suppose my main question when looking at these types of behaviors is whether or not they too become norms because of the principles of evolution.  Following a social norm is something that leads to acceptance within the community an individual is trying to be a part of.  Two distinctions must be made here: first, that we learn how to behave in society through our parents and participation in society; and second, that being accepted by a community helps lead to reproductive success.  If these two assumptions are accepted, than it would seem to follow that the practices that lead to acceptance would be the ones that would survive, in an evolutionary sense.

However, this requires linking all of these cultural traditions with reproductive success, and that implies that the only way a cultural tradition can persist is if it will increase an individual's chance to create offspring.  This is not true for all cultural patterns and I am uncomfortable concluding that all social norms and accepted practices have become the norm because of the principles of evolution.  I am not sure if one can say that cultural practices such as storytelling are now performed as a human standard because they were once critical to human survival.  I think that these larger patterns, such as western society's tendency to lean towards a mother-and-father nuclear family structure, cannot be explained by simply saying that they were once critical for human survival and have persisted since then.  While it is interesting to use Darwin's story of evolution to analyze other concepts such as cultural patterns, it is important to remember that there are no concrete observations that we can use to verify the story or create a new story. There is definitely some sort of connection between the two, but perpetuation of cultural traditions cannot be fully explained by the same laws that govern Darwinian evolution.


1. "Narrowing Search For Behavior-Related Genes In People With Williams Syndrome" Medical News Today. (10 February 2009)

2. Darwin, Charles. "On the Origin of Species".  Ed. Joseph Carroll. Canada: Broadview Texts, 2003. Pgs. 247, 397-398


Paul Grobstein's picture

Behavior and culture: beyond biological evolution

A nice bridge to the rest of the course. Is behavior determined by genes? Influenced by them? Is culture determined by genes? Influenced by them? Is evolution in the sense of random change/differential survival relevant only for thinking about genes, or might it be relevant in thinking about other things as well?  Such as "perpetuation of cultural traditions" even if those involve something other than genes?