The Economist has a survey in its year-end double issue: “New theories and techniques have revolutionised our understanding of humanity’s past and present.”
The proverbial Martian, looking at that darkened Earth, would probably have given long odds against these peculiar apes making much impact on the future. True, they had mastered the art of tool-making, but so had several of their contemporaries. True, too, their curious grunts allowed them to collaborate in surprisingly sophisticated ways. But those advantages came at a huge price, for their brains were voracious consumers of energya mere 2% of the body’s tissue absorbing 20% of its food intake. An interesting evolutionary experiment, then, but surely a blind alley.
This survey will attempt to explain why that mythical Martian would have been wrong. It will ask how these apes not only survived but prospered, until the time came when one of them could weave together strands of evidence from fields as disparate as geology and genetics, and conclude that his ancestors had gone through a genetic bottleneck caused by a geological catastrophe.