While researching Martha's Vineyard, an island off the coast of Massachusetts, anthropologist Nora Groce made a remarkable discovery. She learned that from the 1600s until the early 1900s, almost all the residents of two towns on the island—West Tisbury and Chilmark—were fluent in sign language. During these years, the towns had an unusually high population of deaf people, due to a form of hereditary deafness that ran in many Martha's Vineyard families. Consequently, a bilingual society developed. The islanders didn't attend special sign language classes; they simply learned the language as they grew up. One of the most interesting aspects of the phenomenon was that, in the absence of language barriers, deafness was not perceived as a disability. As one Vineyarder explained to Groce, deaf people were seen as "just like everyone else."