Origin story

We homo sapiens evolved and succeeded when other hominins didn't-but now our expansionist drive is threatening the planet

- By Laura Spinney

In an institute in Germany, scientists are growing "Neanderthalised" human brain cells in a dish. These cells form synapses and spark as they would have done in a living Neanderthal as she (they are female cells) foraged or breastfed or gazed out of a cave mouth at dusk. That is the spine-tingling opening gambit of a book co-authored by one of the directors of the institute, Johannes Krause, and the information that sets it apart from a host of popular science books that attempt to predict humanity's future based on our evolutionary past.

A mere 90 genetic differences distinguish modern humans, Homo sapiens, from Neanderthals, Homo neanderthalensis. That's paltry given the roughly 20,000 genes that make up the human blueprint, and not all of them affect the brain. Yet those 90 differences could explain why Neanderthals died out, some 40,000 years ago, while we went on to dominate the planet. They could hold the key to how we, the apparently more adaptable human type, might adapt again before we destroy the ecosystems we depend on, and ourselves along with them.