Underdiscussed: Language Death
Vae victīs: globalization poses the most severe existential threat to language diversity.
According to the latest available data (as of this writing) from UNESCO, there are 2726 endangered or extinct languages, with over 7000 total languages discovered. That means 35 to 40% of the world's languages are threatened. With language death follows weakening of cultural ties and traditions, loss of folktales, oral history, and ancestral knowledge.