He was bitten over 1,000 times to establish an insect bite pain scale. Justin Orvel Schmidt is an American entomologist at the University of Arizona (western United States). In the 1980s, he decided to conduct an experiment: being bitten by hundreds of species of insects to assess the different degrees of pain. This pain scale ranges from 1 to 4, from least painful to most painful. According to the Schimdt scale, the most painful insect bite is that of the Paraponera ant which inhabits the tropical rainforests of Central and South America.