Genes track history of buffalo taming
doi:10.1038/nindia.2007.23 Published online 4 October 2007
Scientists have dug deep into the genetic history of one of Asia's important livestock, the water buffalo Bubalus bubalis, to find that it was most likely domesticated in the west of the Indian subcontinent. Also, the animal went through complex domestication processes and had more than one maternal lineage.
Researching the poorly-studied animal, a team from the Centre for Cellular and Molecular Biology in Hyderabad tried to understand the relationship among the maternal lineages of Indian river buffalo breeds and their domestication process1. "We analyzed the mitochondrial D-loop region of 217 buffaloes representing eight breeds from different parts of India. We studied them alongside published sequences of Mediterranean buffalo," says Satish Kumar, lead author of the study.
Even after initially being domesticated (perhaps prior to the Harappan civilisation), the species saw a significant flow of maternal genes from the wilderness. "Possibly a very large number of females contributed to the domesticated stocks. Alternatively, there might have been a 'trickling in' effect in terms of continuous addition of females from the wild to the domestic herds over a period," Kumar says.
The most likely area where domestication of the buffalo flourished was the conventional modern day breeding tract of Mehsana, Surati and Pandharpuri, the study found. This supports the popular archaeological theories on the domestication of the animal considered a prime driver of the region's agro-based economy.
The team found one major ancestral lineage (clade) of the buffalo with six internal branches. Analysis revealed that the branches had evolved from more than one set of haplotypes suggesting that the species had undergone complex domestication events in its past. In addition, the team found several singleton haplotypes. Using rho statistics, they estimated that 6300 years before present (pre-Harappan period), one set of haplotypes of the Indian domestic buffalo underwent expansion.
The data could be an important resource for animal scientists considering that the population of the Indian river buffalo in India is around 98 million, representing 56 per cent of the global numbers. The animal constitutes 35 per cent of the bovine population in India but contributes more than 55 per cent of the national milk production.
- Kumar, S. et al. Phylogeography and domestication of Indian river buffalo. BMC Evol. Biol. doi: 10.1186/1471-2148-7-186 (2007).