Most of us have heard warnings that humans are destroying the Earth and all that lives on it since we were toddlers. So much so that the message has lost its urgency. More than that, we've become cynical. What good can we do when in the United States, for example, every bill aimed at cutting back on waste, reducing fossil-fuel consumption or preserving biodiversity is killed off by lobbyists with deep pockets and short-term financial goals? Can we do anything, and why should we, when the real offenders have made themselves exempt?

Speaking at recent press conferences to mark prizes awarded in recognition of their contribution to global environmental conservation, Robert May, Norman Myers and Jane Goodall told us what we can do, and why.

If species extinction continues at its current rate, which is more or less the same as that when the dinosaurs were extinguished, then we will soon find out (or our grandchildren will) what it is like to live in an impoverished world. That's if we survive.