The Laetoli Footprints

team of paleoanthropologists led by Mary Leakey confirmed the bipedality of A. afarensis with another remarkable find in Tanzania: the famous “Laetoli footprints.” In 1976, Andrew Hill and another member of the team were taking a break by indulging in a favorite field pastime: pelting each other with chunks of dried elephant dung. Looking for ammunition in a dry stream bed, Hill stumbled upon a line of fossilized footprints. After careful excavation, the footprints turned out to be an ...

 Australopithecus afarensis' Hip Bone Indicates She Could ...

When Lucy’s hundreds of fragments were assembled, she turned out to be a female of a new species, Australopithecus afarensis, dating back 3.2 million years. She was between 20 and 30 years old, 3.5feet tall, weighing a scant 60 pounds, and possibly afflicted with arthritis. But most important, she walked on two legs. How can we tell? From the way that the femur (thighbone) connects to the pelvis at one end and to the knee at its other. In a bipedally walking primate like ourselves, the fem...

 Our Sinuses are Upside Down

Another consequence of our own shift from quadruped to biped concerns the sinuses, which give such grief to many of us (including me at the moment of writing) because their drainage hole is in the very last place a sensible designer would have chosen. Williams quotes an Australian colleague, Professor Derek Denton:* 'The big maxillary sinuses or cavities are behind the cheeks on either side of the face. They have their drainage hole in their top, which is not much of an idea in terms of using...