A biologist who won the Nobel Prize for Medicine for his research into split-brain patients.
After getting his doctorate at the University of Chicago, he showed that much of the mammalian nervous system is hard-wired to carry out specific tasks.
He worked with patients who underwent operations severing the communication channels between their brain hemispheres, showing each hemisphere controls different functions.
He grew up on a farm in Hartford, Connecticut, where he first developed his abiding love of nature.
Alfred Hershey was another winner of the Nobel Prize for Medicine for his research on DNA.