Survival of the friendliest? Why Homo sapiens outlived other humans

We once shared the planet with at least seven other types of human. Ironically, our success may have been due to our deepest vulnerability: being dependent on others

By Kate Ravilious

HUMANS today are uniquely alone. For the majority of the existence of Homo sapiens, we shared the planet with many other types of human. At the time when our lineage first evolved in Africa some 300,000 years ago, there were at least five others. And if you were going to place a bet on which of those would outlast all the rest, you might not have put your money on us.

The odds would have seemed more favourable for the Neanderthals, who had already adapted to live in colder conditions and expanded to inhabit much of Eurasia. Or Homo erectus, who had made a success of living in south-east Asia. By contrast, our direct Homo sapiens ancestors were the new kids on the block, and wouldn’t successfully settle outside of Africa until more than 200,000 years later. Yet, by 40,000 years ago, or possibly a bit more recently, we were the only humans left standing. Why?

Many explanations have been put forward: brainpower, language or just luck. Now, a new idea is building momentum to explain our dominance. Ironically, it may be some of our seemingly deepest vulnerabilities – being dependent on others, feeling compassion and experiencing empathy – that could have given us the edge.

Today, surrounded by computers, phones and all the other clever things we have invented, it is easy to pin our success on our cognitive abilities. But the more we learn about other types of human, the more they seem similar to us in this regard. In the case of Neanderthals, and possibly the mysterious Denisovans, this includes the ability to make sophisticated …