The evidence for a rapid shift in state of the terrestrial
atmosphere-ocean system over the last two centuries (see figure
1) requires a deep time perspective, beyond events of the day.
Tracing the original blueprints of anthropogenic effects on the
terrestrial environments takes us back at least a million years
to the time when – according to research released this month –
the first compelling evidence for human use of fire was found.
Of all life forms which ever existed, only the genus Homo
acquired the skill of igniting and transporting fire. This gave
Homo not only warmth, cooking and protection from animals, but a
high degree of power over nature. Prehistoric hominids burned
large parts of the biosphere and, more recently, combusted
carbon and hydrocarbons derived from fossil biospheres up to 400
million years old. The high intelligence underlying human
inventions has been variously attributed to a large brain size
(Chimpanzees ~395 grams; Australopithecus apheresis ~430 grams;
Homo ergaster ~850 gram; H