The Neander Valley was named after hymn writer Joachim Neander, whose family had changed its name from Neumann, meaning new man. In 1856 quarry workers there found bones they took for a cave bear’s, and schoolteacher Johann Carl Fuhlrott recognized them as an ancient human, three years before Darwin’s On the Origin of Species. This episode traces how the caveman stereotype took hold: Rudolf Virchow blamed the bones on rickets and blows to the head, William King said the species was incapable of moral thought, and Marcellin Boule posed a skeleton as a slouching ape without accounting for its owner’s severe spinal osteoarthritis.

The real Neanderthal was about 5 foot 5 for males, with a barrel chest, hips 31 percent wider than modern men’s, a radiator nose, and a brain averaging up to 1,640 cubic centimeters. They were ambush hunters of straight tusked elephants who made Levallois tools, birch tar glue cooked without oxygen, and yew wood spears. Small, isolated, inbred groups may explain 150,000 years of little technological change. The 2010 genome showed interbreeding, mostly Neanderthal fathers and modern human mothers, before extinction around 40,000 years ago amid competition, mutational meltdown, and the Campanian Ignimbrite eruption.

• Why their thick, wide bodies were a hyperarctic adaptation for holding heat
• Matching upper body injuries in men and women, suggesting both joined dangerous hunts
• Traces of natural pain relievers found in their dental plaque
• About 2 percent Neanderthal DNA in people with ancestry outside sub-Saharan Africa, and 20 percent of their genome surviving overall
• How mitochondrial DNA reveals which parent was the Neanderthal