Bell
Bell began his work on the island in 1883, and did extensive pedigree research but found nothing because Mendelian genetics was unknown at the time. Bell didn't understand why deaf parents sometimes had hearing children or why hearing parents sometimes had deaf children, but believed deaf people should not marry - this resulted in the practice of sterilization of deaf people in America, which continued into the twentieth century. Bell, who is renowned for his oralist beliefs, told the Royal Commission in England that sign language could not be used to help mix deaf and hearing people. He stated that only deaf people could use sign language amongst themselves, despite having seen evidence to the contrary on Martha's Vineyard.
End of an Era
The recessive deafness began to end on Martha's Vineyard for a number of reasons. After the 1840s, people were drawn to California, and during that decade 14 deaf children were born in Chilmark, which had a population of about 350. Thirty years later, the town's population was about the same, but only one deaf child was born there. The deafness also ended because the gene pools on the island finally expanded. After children started attending school in Hartford, some married classmates from there. Even if the newlyweds returned to the island, the classmate's deafness was not caused by the recessive genetics. In the late nineteenth century, "summer people" began vacationing on Martha's Vineyard after former President Grant had visited there, and Portuguese immigrants also began settling on the island. Members of the island community began marrying these off-Islanders, further expanding the gene pool. After 1900, modern conveniences, mass communication, and summer visitors - most of whom brought different attitudes about the deaf, though some did learn sign language - greatly upset the island's social patterns. At the turn of the century, there were 15 deaf people alive on the island, but by 1925 there were only four. By 1945 only Katie West survived, and she died in 1952; the sign language used on the island died out by the 1970s. In 1980 there were four deaf people on the island, none of whom had the hereditary deafness.
