Big Brain: The Origins and Future of Human Intelligence by Gary Lynch and Richard Granger (Palgrave Macmillan, $26.95)

“Sometimes I think my head is so big because it is so full of dreams,” says John Merrick in the play The Elephant Man. He might have been speaking for the Boskops, an almost forgotten group of early humans who lived in southern Africa between 30,000 and 10,000 years ago. Judging from fossil remains, scientists say the Boskops were similar to modern humans but had small, childlike faces and huge melon heads that held brains about 30 percent larger than our own.

That’s what fascinates psychiatrist Gary Lynch and cognitive scientist Richard Granger. “Just as we’re smarter than apes, they were probably smarter than us,” they speculate. More insightful and self-reflective than modern humans, with fantastic memories and a penchant for dreaming, the Boskops may have had “an internal mental life literally beyond anything we can imagine.” Lynch and Granger base their characterization on our current understanding of how the human brain works, describing in detail its physiology and structure and comparing it with the brains of other primates. They also explore what the Boskops’ big brains tell us about evolution (why didn’t they survive?) and about the future of human intelligence (can we engineer bigger brains?). These are questions, one suspects, that even the smallest-brained Boskop would have approved of.