Premise: Theodora Kracaw Kroeber Quinn (March 24, 1897 – July 4, 1979) was a writer and anthropologist, best known for her accounts of Ishi, the last member of the Yahi tribe of California, and for her retelling of traditional narratives from several Native Californian cultures.
Hypothesis: Ishi, the last member of the Yahi tribe, was 90 years old.