Osteoarthritis, back problems, difficult birth – scars of our evolution?

Musculoskeletal disorders are one of the most important challenges of modern medicine worldwide, both in terms of socioeconomic costs and disability-adjusted life-years (DALYs). They are often attributed to maladaptations of our body to our peculiar form of locomotion, upright bipedalism. In my presentation, I will explore the evolutionary origin of major musculoskeletal disorders such as back problems and hip joint osteoarthritis. I will show that these problems represent a relatively recent phenomenon, occurring only during the last few decades, and thus are unrelated to our skeletal adaptations. Another trade-off between our skeletal adaptation for upright bipedal locomotion and our large brain size is often said to explain the unusually difficult birth in humans compared to other mammals. I will demonstrate that this evolutionary compromise has a much deeper origin and was not caused by the enormous enlargement of our brains but instead was likely a prerequisite for the evolution of our cognitive capabilities.