But there has been real progress in the last decades in extending the lives of other organisms, like fruit flies and nematode worms, and even mammals like mice... and if i may... ..that suggest we're getting closer. if i may introduce the jellyfish, we now know there is one species ofjellyfish, some call it the immortaljellyfish, which has the ability — i think it's technically called transdifferentiation — to redevelop itself, to go back to its earliest form and then grow again. we seem now to be able to learn a great deal in terms of genetic engineering from other living organisms. if we...