Another brother clade, Haplogroup O-P31, has an impressive extent of dispersal, as it is found among the males of populations as widely separated as the Kolarians of India and the Japanese of Japan; however, Haplogroup O-P31's distribution is much more patchy, and the Haplogroup O-P31 Y-chromosomes found among the Mundas and the Japanese belong to distinct subclades.
They were of interest as being the westernmost representatives of the Munda family of speech.
They constitute a branch of the Austroasiatic language family, which means they are distantly related to Vietnamese and Khmer (Cambodian).
Emeneau specified the tools to establish that language and culture had fused for centuries on the Indian soil to produce an integrated mosaic of structural convergence of four distinct language families: Indo-Aryan, Dravidian, Munda and Tibeto-Burman.
Languages of India | Indo-European languages | Celtic languages | Slavic languages | Algonquian languages | Turkic languages | Bantu languages | Romance languages | Berber languages | Australian Aboriginal languages | Germanic languages | Goidelic languages | Arawakan languages | North Germanic languages | Indigenous languages of the Americas | Austroasiatic languages | Indo-Aryan languages | Polynesian languages | Northwest Caucasian languages | Munda languages | Mongolic languages | French-based creole languages | Songhay languages | Semitic languages | Dené–Yeniseian languages | Common European Framework of Reference for Languages | Visayan languages | Tupian languages | Tibeto-Burman languages | Pama–Nyungan languages |
Harrison has done field work on endangered languages in Siberia and Mongolia Tuvan, Tsengel Tuvan, Tofa, Ös, Tuha, Monchak, Munda, and also in Paraguay, Chile, Papua New Guinea, and India.
Most languages spoken in India belong either to the Indo-European (ca. 74%), the Dravidian (ca. 24%), the Austroasiatic (Munda) (ca. 1.2%), or the Tibeto-Burman (ca. 0.6%) families, with some languages of the Himalayas still unclassified.
Six indigenous Nicobarese languages are spoken on the islands, which are part of the Mon–Khmer branch of the Austroasiatic language family, which includes Mon, Khmer and Vietnamese languages of Southeast Asia, and the Munda languages of India.
However, his greater fame lies in his contributions to the Munda languages and to Austroasiatic linguistics in general.