FIRST STEPS: How Walking Upright Made Us Human

A fun and scientifically deep stroll through history, anatomy and evolution. From an evolutionary point of view, we humans are novices to walking on two legs. Swapping from all fours to bipedalism brought with it a host of problems. We could no longer outrun most predators or most prey. Bad backs, hips and knees and hernias became much more common as a result of the pressure of gravity and narrow hips, which make upright walking more efficient, also make childbirth hazardous for both baby and mother. Bipedalism can be viewed as a grand evolutionary experiment, one which has been going on, with varying degrees of success, for some seven million years. In the last 4.5 million years a number of different but related hominins have walked the Earth and Homo sapiens is just one of them - or so Jeremy DeSilva thought. Then, in the early 2000s he was part of a team that discovered and described two newly discovered hominins in Chad, that were some 7 million years old and showed that they too walked on two legs - so it was time for a radical rethink! Here he goes right back into the fossil record, leading us on a sweeping tour, explaining what we currently know about our earliest ancestors, how they walked and how they lived. Bipedalism freed our arms for tool use and other highly dextrous activities, it freed pectoral muscles and lungs for speech and the fact that it made us more vulnerable to predators caused us to live cooperatively in organised communities, sharing knowledge and skills. 334pp.