OK, so let's take it that global warming is coming: that temperatures are set to rise by easily 3°C by the end of the century. Disaster, right? The tropical rainforests - lungs of the planet - will die, CO2 levels will thus rise even faster, a runaway process will set in and planet Earth will be transformed into a baking lifeless hell.
Not so much, according to top boffin Carlos Jaramillo of the US Smithsonian Institution. Jaramillo, who works at the Smithsonian's Tropical Research centre, says that 60 million years ago temperatures were up to 5°C higher than now and atmospheric CO2 was running close to 1000 parts per million - way beyond the planet-busting thresholds set by the UN - and yet the rainforests flourished.
"It is remarkable that there is so much concern about the effects of greenhouse conditions on tropical forests," says Jaramillo's Smithsonian colleague Klaus Winter.