- Haydon Mort
- Recife - Pe
Visiting Professor, Universidade de Pernambuco
A forth way for continuing human evolution
Dr Fineberg presented 3 possibilities for the future evolution of humans. They were 1) It won't happen, 2) Natural selection may slow but it will inexorably continue, 3) Neo-evolution through the tweaking and enhancement of the human genome. I agree that third will probably happen.
Nevertheless, I see a forth way, which I believe will a more fundamental driver of change. A first order background, upon which neo-evolution will play out.
It works like this. Mental illness is soaring in developed and emerging economies. The reasons are complex, but likely due to an interaction of a 'dumbing down' of the media and a more vegetative lifestyle. How would this affect the gene pool? Would people with genetic pre-dispositions to mental ill-health be less likely to reproduce?
Consider the growing problem of obesity, a symptom of socio-economic 'development'. Overweight people are more likely to survive if they have a biology that, for example, reacts more quickly to increases in blood-sugar levels, or de-clogs arteries. Those who don't possess these biological pre-dispositions are less likely to survive. Hence the gene pool would trend towards a creating a metabolism that is altered to suit the environmental pressure that we created (a high calorie diet).
A final example. Pollution. Recent studies published in high-impact journals show the emerging impact of environmental petrochemicals on child and adult physiological and neurological development. Who is more likely to survive? Anybody who has a genome more resistant to these chemical. We can expect to see the gene pool gradually move in away that help humans survive in petrochemical rich environments. This may, of course, come at the expense of our ability to survive in non-petrochemical rich environments.
So in summary. Our immense environmental footprint may feedback and impact on our own biological evolution. If this is true, humans are already evolving as we speak, without the need of direct genetic manipulation.