<P> Water buffalo were domesticated in Indian subcontinent about 5000 years ago, and in China about 4000 years ago . Two types are recognized, based on morphological and behavioural criteria--the river buffalo of the Indian subcontinent and further west to the Balkans and Italy, and the swamp buffalo, found from Assam in the west through Southeast Asia to the Yangtze valley of China in the east . The present - day river buffalo is the result of complex domestication processes involving more than one maternal lineage and a significant maternal gene flow from wild populations after the initial domestication events . Twenty - two breeds of the river type water buffalo are known, including Murrah, NiliRavi, Surti, Jafarabadi, Anatolian, Mediterranean, and Egyptian buffalo . China has a huge variety of buffalo genetic resources, comprising 16 local swamp buffalo breeds in various regions . </P> <P> Results of mitochondrial DNA analyses indicate that the two types were domesticated independently . Sequencing of cytochrome b genes of Bubalus species implies that the domestic buffalo originated from at least two populations, and that the river and the swamp types have differentiated at the full species level . The genetic distance between the two types is so large that a divergence time of about 1.7 million years has been suggested . The swamp type was noticed to have the closest relationship with the tamaraw . </P> <P> The water buffalo population in the world is about 172 million . </P> <P> More than 95.8% of the world population of water buffalo are found in Asia, including both river and swamp types . The water buffalo population in India numbered over 97.9 million head in 2003, representing 56.5% of the world population . They are primarily of the river type, with 10 well - defined breeds comprising Badhawari, Murrah, Nili - Ravi, Jafarabadi, Marathwada, Mehsana, Nagpuri, Pandharpuri, Toda, and Surti . Swamp buffalo occur only in small areas in the north - eastern part of the country and are not distinguished into breeds . </P>

How many water buffalo are left in the world