Researchers at the National Institutes of Health have made a significant discovery that challenges the long-held theory about the origin of small dog breeds. According to the study, small dogs such as Pomeranians and Chihuahuas share a genetic mutation with ancient wolves, specifically a gene called IGF-1 that regulates growth hormone. This mutation was present in wolves more than 50,000 years ago, long before domestication, and was also found in a 54,000-year-old Siberian wolf.
The study’s lead geneticist, Elaine Ostrander, suggests that nature had kept the mutation in reserve for tens of thousands of years until it was needed, implying that small body size has been a part of canine evolution for thousands of years. The researchers also analyzed ancient wolf DNA and found that the mutation was not unique to wolves, but was also present in other canid species such as coyotes, jackals, and African hunting dogs.
Elaine Ostrander (Via Elaine Ostrander/Twitter)
The discovery has significant implications for understanding canine domestication and body size. Ostrander notes that the study’s findings “tie together so much about canine domestication and body size, and the things that we think are very modern are actually very ancient.” This suggests that humans may not have been the primary driving force behind the domestication of small dogs, as previously thought.
The researchers plan to continue investigating the genes that regulate body size in dogs, with the aim of gaining further insights into canine evolution and domestication. The study’s findings have been published in the Current Biology journal, providing new evidence for the complex and ancient relationship between humans and dogs. The discovery of the genetic link between ancient wolves and small dog breeds sheds new light on the history of canine domestication and the evolution of small breeds, and highlights the importance of considering the natural history of dogs when studying their origins.
