@Shutsumon I'm not sure about the vowels. It's not because languages uses the same vowels that there is some sort of borrowing between them.
Caucasian languages are very poor in that domain (only 3 in the link you posted), while Germanic languages tend to be richer (Standard German have at least 14 vowels).
@Feufochmar I wasn't being serious. It was supposed to be a joke about Germanic languages excessive number of vowels (I think English has at least 12 as well).