Monday, 4 August 2014

Continuing Evolution of the Human Race

For my first year of university, I decided to fulfil my science requirement by taking a first year biology course taught by David Suzuki. My reasoning was simple: I was interested in biology (of the evolutionary persuasion, not so much the details of cell structure or function), and I had listened to Dr. Suzuki almost weekly for almost all of my conscious life, both on the radio (Quirks and Quarks) and on television (The Nature of Things). To listen to him in person would be interesting and fun, I was sure.

And it was. I learned interesting facts about chromosomal abnormalities, gene penetrance, homology and convergence, and so on. And when the time came to choose the topic of my term paper, I decided to throw myself into finding answers to a topic that had always intrigued me: now that we live in cities, what are the evolutionary pressures and trends that are shaping us. In other words, what are we evolving into?

The resulting 36-page magnum opus was a peculiar item. Its sections had epigraphs by Douglas Adams, Lewis Carroll, and Robert Heinlein, among others. Its scope was broad, including evidence of the genetic component of behaviour, the miscarriage rate among prisoners, and so on. Its major component was that the stresses of city life cause fatalities, miscarriages, poor parenting, and poor survival ability often enough to have an evolutionary effect. My most important conclusions were, first, that the genetic load (roughly speaking, the proportion of genes that are potentially deleterious) will increase in the foreseeable future, due to medical care, and that those who are genetically predisposed to feel less stress in an urban environment will have an evolutionary advantage. Those people's genes will spread through the population, I said. In my conclusion, I used a quotation from Robert Heinlein's book Beyond This Horizon about a person with a mutation that made him "more civilized" than could reasonably be expected. I saw such genes as the present trend and the future reality of human evolution.

The reason that I am recalling that early work is that a recent study published in Current Anthropology is making me feel justified in my conclusions. It purports to show that many of the physical changes that occurred over time in humans correlate to reductions in testosterone levels and, further, that reductions in testosterone levels correlate to advances in human social organization. Many of those changes, which have been collectively termed "juvenalization" or "neoteny," could therefore be called "feminization" instead. There is much to think about here, and I'll have to do a little reading. The main point, though, is I feel my early paper, the work of a very young dilettante in biology, has received some professional support. It may well be that mankind has displayed a long-term trend to becoming more civilized.


  1. :-)
    Yes, the bold impetuosity of youth.
    And now I wonder: is such behaviour also contra-indicated by natural selection in an urban environment? Does propaganda have an effect on genetic mutation, or is it a natural urban evolution/developement? This of course assumes that there was less pressure to conform within small non-urban communities. And that is not, I believe, a tenable condition. At least not from my personal experience of small town Canada, anyway.

    1. Hey, Guy. Good to hear from you.

      I felt justified in assuming that social stress was greater in an urban environment because there are just more people. I cited studies of "behavioural sinks" among rats to justify the assumption. Rightly or wrongly.

      I don't get your point about propaganda and mutation, though. Care to explain?