Scientists led by Professor Greger Larson from Oxford examined the DNA sequences of modern feral Hawaiian pigs and discovered that a novel mutation is responsible for their black coats, a significant finding because the pigs were expected to have either the Asian or the European genetic mutation leading to their black colour.

A study has said wild pigs would naturally have camouflaged coats. However, human societies have independently selected domesticated pigs that express the trait of black-coloured coats.

Scientists find that today’s federal pigs are mainly the descendants of the Pacific family brought by the Polynesians. In addition, the scientists identified a new genetic mutation responsible for the black colouring of their coats.

An international team of researchers studied the mitochondrial DNA and MC1R gene sequences in tissue samples collected from 57 modern feral Hawaiian pigs. They found a novel mutation in all the black-coloured pigs which is different to the mutation in European and Asian domestic pigs with black coats.

This finding suggests that for thousands of years, humans in different parts of the world have been independently selecting and breeding pigs for their black colour.

Senior author Professor Greger Larson, from the Palaeogenomics and Bio-Archaeology Research Network at the University of Oxford, said: “No wild boar have black colours since natural selection only allows camouflaged pigs to survive long enough to reproduce. Humans have selected for black coats at least three times independently in domestic pigs in Europe, Asia and the Pacific.”