From their research arose one of the most influential, ground-breaking scientific ideas of the 20th century - the Gaia hypothesis, named after the ancient Greek goddess of the Earth, a nurturing "mother" of life. But is it correct? New scientific findings suggest that the nature of life on Earth is not at all like Gaia. If we were to choose a mythical mother figure to characterise the biosphere, it would more accurately be Medea, the murderous wife of Jason of the Argonauts. She was a sorceress, a princess - and a killer of her own children.

. Around 3.7 billion years ago, we think a "methane crisis" nearly wiped life off the face of the Earth almost as soon as it had got going. Methane-belching microbes filled the atmosphere with a hazy smog that all but blocked out the sun (see a timeline of Medean events).

If these models are correct, life on Earth is already in its old age.

long-term, and terminal, decline of CO₂

has already started

burning fossil fuels is just a blip.