A study of ancient dna has shed new light on the history of dogs, suggesting they have been associated with humans for thousands of years. The research has uncovered evidence of dogs in various parts of the world, including the americas and europe, with some findings indicating that dogs may have been present in these regions earlier than previously thought. The exact timing and details of dog domestication and migration are still unclear, with different reports suggesting dogs may have been present in certain areas for anywhere from 12,000 to nearly 16,000 years.