We have long known from studies of contemporary English that language change begins with young women. We now have “real-time”, historical evidence (from Early Modern letters) that young women are language innovators:
http://qz.com/474671/move-over-shakespeare-teen-girls-are-the-real-language-disruptors/
Read about the work of historical sociolinguists Terttu Nevalainen and Helena Raumolin-Brunberg:
http://homes.chass.utoronto.ca/~cpercy/courses/6362-gregoire.htm