Language not only defines humans as a species, placing us head and shoulders above even the most proficient animal communicators, but it also beguiles us with its endless mysteries. For example... How did different languages come to be? Why isn't there just a single language? How does a language change, and when it does, is that change indicative of decay or growth? How does a language become extinct?   In today's episode I speak with Dr. John McWhorter, a linguist from Columbia University. He, addresses these and other issues, such as how a single tongue spoken 150,000 years ago has evolved into the estimated 6,000 languages used around the world today. We go broad and deep. For the broad, we explore language families, starting with Indo-European, comprising languages from India to Ireland including English. Other language families discussed are Semitic, Sino-Tibetan, Austronesian, Bantu, and Native American. This gets us into the heated debate over the first language. For the deep, we get into pidgins and creoles. When people learn a language quickly without being explicitly taught, they develop a pidgin version of it. Then if they need to use this pidgin on an everyday basis it becomes a real language, a creole. Some people argue that Black English is a creole, and Professor McWhorter really gets into this issue.