Depends what perspective you take - we haven't escaped the basic biological limits imposed us by hundreds of thousands of years of evolution as a species, even

Depends what perspective you take - we haven't escaped the basic biological limits imposed us by hundreds of thousands of years of evolution as a species, even if we've stretched some of them a little. I don't doubt someone from 100 years ago could jump into today's world and adapt reasonable readily (and v/v). But at some point I don't expect that will continue to be true, esp. once we start messing around with our genetic makeup. Even the food we consume isn't so radically different to that from 100 years ago, but again, not hard to imagine some sort of future where our bodily energy supply becomes quite unrecognisable from what it is today.