Here on Earth, I suspect that we are going to want to regulate the application of genetic modification and cyborg techniques on grounds of ethics and prudence. This links with another topic I want to come to later, which is the risks of new technology. If we imagine these people living as pioneers on Mars, they are out of range of any terrestrial regulation. Moreover, they've got a far higher incentive to modify themselves or their descendants to adapt to this very alien and hostile environment.
They will use all the techniques of genetic modification, cyborg techniques, maybe even linking or downloading themselves into machines, which, fifty years from now, will be far more powerful than they are today. The post-human era is probably not going to start here on Earth; it will be spearheaded by these communities on Mars. That's the vision I would have of Mars. It's people out there who will perhaps lead to these developments, which will then eventually lead to posthumans, maybe electronic rather than organic, spreading far beyond our solar system. If that's happened elsewhere, that's the sort of thing we might detect.
LORD MARTIN REES is a Fellow of Trinity College and Emeritus Professor of Cosmology and Astrophysics at the University of Cambridge. He is the UK's Astronomer Royal and a Past President of the Royal Society. Martin Rees's Edge Bio Page