May 19, 2008
Evolution is Dead, Long Live Evolution!
John Harris defends enhancement in the Times: Who's afraid of a synthetic human?. I'm generally just nodding in agreement. It is largely a version of his Oxford talk last week.
One interesting point is the difference between natural evolution and enhancement evolution. In the first, fitness is determined by a natural environment and selection is done through differential reproduction rates - often by the unfit simply being killed of by the environment. Diversity is generated through random, simple mutations. In enhancement evolution fitness becomes dominated by the desires and projects of intelligent beings, and selection (if it occurs) happens prenatally (e.g. through PGD) - instead the "mutations" are no longer random and can be very complex.
This means that fully mature enhancement evolution is much more humane, in that fewer lives have to be sacrificed in the selection step. The ends may still be problematic, but even if natural evolution were for some reason aiming at maximum happiness it would achieve that goal by killing a large number of unsuccessful individuals. Natural evolution is not immoral since there is no moral agent responsible for it, but it is a quite painful process. Enhancement evolution is subject to moral consideration since the beings doing it are moral beings; hence it is possible to have "moral evolution" in the sense that it aims at good goals and achieves them using good means.
Enhancement evolution also extends the environment that is acting on the genome beyond the traditional physical and ecological environment to an environment including culture, economy and technology. Natural evolution can only react to the surface aspects of this: changing butterfly colouration as a response to pollution or evolving antibiotic resistance is reactive. Enhancement evolution can be proactive: if we know that the climate is going to get hotter, colder, more radioactive or filled with nanobots we can engineer that consideration into other organisms before it happens. By having intelligence involved in the evolutionary process it does not just become quasi-Lamarkian but it even gains foresight. Sure, limited and fallible foresight, but infinitely more than natural evolution could ever produce.
Right now we are in a slow transition from natural to enhancement evolution. We have removed many of the big selection pressures and made reproductive fitness rather independent of genetic fitness (as it would have been in our environment of evolutionary adaptedness). We are doing minor selection (the most dramatic is probably current eugenic programs against some genetic diseases) and will likely be doing PGD real soon now.
Transgenic activity is happening among a handful of species - but we have already done enhancement evolution for millennia across plants and animals. The real shift happens when the human-determined selection/fitness processes become more significant than natural selection/fitness processes (the targeted mutation ability just makes possible jumps more radical and starts allowing non-Darwinian evolution). That might already be close to happening today among humans given that we have reduced external selection pressures so much. It just takes a little bit more genetic testing and counselling and we will already be evolving according to enhancement evolution rather than natural evolution.
(Another version of this post, with some further thinking, has been added to Ethics in the News)
Posted by Anders3 at May 19, 2008 02:51 PM