Elizabeth Thomas was born in 1931, attended Smith College and Harvard University, and spent three years in the 1950s among pre-contact San who occupied a large area in what is now Namibia and Botswana, an area that was still “unexplored.” This word is in quotation marks because archaeological studies done later found a San encampment which was occupied continuously for more than 30,000 years and another encampment which was occupied continuously for more than 80,000 years, and the San had done the exploring. There, she visited the San and also the local lions, whose relationship with the San was most interesting, and she wrote two books about the experience, The Harmless People, published in 1959, and The Old Way: A Story of the First People, published in 2006.
She also spent a summer alone on Baffin Island observing wolves. This appears in The Hidden Life of Dogs, published in 1993. She then studied mountain lions and captive circus tigers. Her findings appear in Tribe of Tiger: Cats and their Culture, published in 1995. She later did a study of the white tail deer who live on her land in New Hampshire. This was published as The Hidden Life of Deer in 2009. She has also written two novels, Reindeer Moon (1981) and The Animal Wife (1990), about people who lived in Siberia during the Paleolithic, combining what she learned from the African savannah with what she learned from Baffin Island. She has written other books as well.
She was married to Stephen Thomas (a historian and political activist) until his death in 2015. They have two children, a daughter, Stephanie Thomas (an activist for disabled civil rights), and a son, Saibhung Singh Khalsa (until recently a French mountain guide, now a musician). They have four grandchildren and one great-grandchild.