Each of the tribes he observed represented a different language family within the country.
Some of those language families have no known members outside the Caucasus area.
The standard does not cover all language families used by linguists.
Native groups can also be classified by their language family.
The two are the only members of the Bunuban language family.
Several tribes and language families would eventually form along the coast.
He has also written about other language families and endangered languages.
Other, smaller language families of Africa follow quite regional patterns.
They have not been definitely linked to any other American language family.
Most of the world's languages are known to belong to language families.
