I'm just had my tooth out on the NHS. A few years ago, I had a… - Sally's Journal
|Date:||August 8th, 2006 12:31 pm (UTC)|| |
There's also the point that 'fitness' in Dawinism isn't an absolute quality - but is relative to the current circumstances. A phenotype that may be a liability in some circumstances can be an advantage in others. I would therefore expect variability in a population to be a better guarantor of long term survival than its apparent health in its current circumstances. Perhaps then, saving even the apparently most useless is a viable evolutionary strategy - to keep breeding from a big a variety of human beings as we can and to keep our gene pool as varied as we can - even if some of the resulting phenotypes seem apparently to be less useful than others in the short term.
I remember reading an article about some Dutch researchers who were studying populations of tits (no giggling there at the back) and identified two quite distinct behaviour patterns. Some tits were very bold and pushy, and others were very timid and nervous. It turned out that during times of dearth, the pushy tits did better (as measured in survival rates, I think), because they were willing to take more risks to get food, but during times of plenty survival rates were much higher amongst the paranoid tits, because the pushy ones got eaten by cats a lot.
Actually, that may be the wrong way round because my memory is rotten, but the observations neatly illustrated wryelle
's point about varying circumstances, and the population of the two behaviour patterns was largely stable over time.