The Greater New Guinea area holds a large number of language isolates, belonging to the most diverse and isolate regions of the world. The number of isolates, and the linguistic diversity more generally, has bewildered every generation of Papuan language researchers. The speakers of the Tambora language of Central Sumbawa fell victim to a gigantic volcanic eruption in 1815, and the language must have gone extinct after the subsequent death of a few survivors. Maybrat is spoken by a sizeable population in the central area of the Bird's Head of Indonesian Papua. The language has a divergent dialect known as Karon Dori, which is sometimes counted as a separate language. Mpur is spoken by some 7,000 speakers in the north-central area of the Bird's Head of Indonesian Papua, to east of Abun. Tanahmerah, also known as Sumeri, is the language of the area with the same name along the Gondu and Bapai Rivers of the northeast of the Bomberai Peninsula.