The heated debate over the UK's revised fertility law is more than just a local issue. Because its supporters are being forced to justify innovations as radical as half-human, half-animal embryos, they have to dig deep for answers to fundamental questions -- with some surprising results. Bioethicist John Harris, for instance, uses the proposed changes to rhapsodise about the end of humanity as we know it. "Darwinian evolution has taken millions of years to create human beings; the next phase of evolution, a phase I call 'enhancement evolution', could occur before the end of the century," he writes in the London Times. "The result may be the emergence of a new species that will initially live alongside us and eventually may entirely replace humankind."

Harris looks beyond the experiments being proposed at the moment to the moral imperative to create "better creatures than ourselves, longer-lived, more resistant to disease and injury, healthier and better adapted to a changing environment".

"Some of these possibilities are so radical that the creatures benefiting from them would no longer be 'human', in the way we think of it," he writes. "The end of humanity then is not in itself a concern; making sure that those who replace us are better than we are is a huge and timely concern." ~ London Times, May 17