the Moorland Mousie Trust, a British organisation, was established to assist in the preservation of the Exmoor pony. With very limited demand for Exmoor colts, the organisation works to raise funds for the gelding, handling and training of these ponies. In 2006, the Trust opened the Exmoor Pony Centre, on Exmoor. Until 2009, every purebred registered Exmoor was hot branded for individual identification. Then, with microchipping offering a viable alternative, in-ground (not moorland herds) breeders ceased to brand. A few years later, hot branding became illegal throughout Britain for all except semi-feral ponies, for which there is no other workable alternative. Currently, the UK Rare Breeds Survival Trust watchlist includes the Exmoor breed in its most threatened category, "Priority", based upon the number of breeding animals and the level of in-breeding. Whilst worldwide the total population numbers around 4,000 (the vast majority within the UK), Exmoor Pony Society estimates the number of breeding animals is only around 600. The Livestock Conservancy in North America also considers the population of the Exmoor pony to be at "threatened" levels. Prehistoric origin theories Some claim that the Exmoor pony descends directly from the wild horses of north-west Europe, uninfluenced by domestic horses. Others consider that Exmoor ponies have a fully domesticated origin. Modern DNA research has not yet conclusively determined the breed’s origins: studies indicate they share their maternally inherited mitochondrial DNA with various other horse breeds from across the world, and their paternally inherited Y-chromosome is identical to that of most other domesticated horses. Wild horses have lived in Britain for hundreds of thousands of years. Some remains found date as early as 700,000 BC, while others are as recent as 3,500 BC. No genetic studies to date have correlated these prehistoric remains to any modern breed. What has been studied are Y-chromosomes (Y-DNA) and mitochondrial DNA (mtDNA). The Y-chromosome is passed on through the male line, and worldwide shows very little genetic variation in horses, except for a second Y-chromosome haplotype found in China, suggesting that a very limited number of stallions contributed to the original genome of the domestic horse. The Exmoor pony shares this general Y-chromosome haplotype. In contrast, mitochondrial DNA is passed on though the female line, and shows far more variation than Y-DNA, indicating that a large number of wild mares from several regions have contributed to modern domestic breeds. Some mtDNA-haplotypes have been found in DNA