Letter: A surprising part of Gaia's self-correcting strategy

From John Entwisle, Leatherhead, Surrey, UK

After reading your recent article on the Gaia hypothesis, I wondered whether anyone had considered that the human species may be a solution to one of the biggest threats facing Gaia (10 August, p 13).

It seems that humans have just the right amounts of aggression and intelligence to create things that could alter the trajectory of an incoming asteroid that is capable of causing a mass extinction.

The last one of these was quite bad and the next could be worse. It would be a risky strategy on Gaia’s part, but if the species also enables life to be established on a second planet that would improve the long-term odds of life’s survival.