Do We Know How "Gender" Arises in Language?

Also, is Chomsky's "Universal Grammar" still a thing?

NOTE: Do you have a language question for John? Leave a comment or email lexiconvalley@booksmartstudios.org, and he may answer it in a future post!

This week, I want to answer two questions from the same person, Beirne Konarski, who asks:

In Indo-European, languages with gender feminine nouns tend to end in -a, but any sense of femininity for most of the nouns is long gone. Back when gender meant something in Indo-European, was the equivalent of -a stuck on to the nouns to mark them with the gender, or did -a just become a way of keeping the gender going after it ceased to mean anything?