David A. Leopold is in the Section on Cognitive Neurophysiology and Imaging, National Institute of Mental Health, Bethseda, Maryland 20814, USA. In the 1930s, the neurosurgeon Wilder Penfield ...
Around 1% of the world’s population are born with extra fingers or toes. Thiti Sukapan/ Shutterstock Thanks to millions of years of evolution, the human body has become well versed in its ...