African village dog

The African village dog is a type of dog that is not a mix of modern breeds but rather a direct descendant of indigenous dogs.[1] While a study done by Cornell University caused some to believe that Africa was the earliest site of domestication for dogs, a further study by Peter Savolainen reaffirmed the theory that dogs were first domesticated in China.[2]

Genetic diversity

In an analysis of hundreds of semi-feral African village dogs conducted by Cornell University, it was found that dogs from most regions of Africa are genetically distinct from both non-native breeds and mixed-breed dogs.[1] The Village Dog Genetic Diversity Project, field researchers from the University of California, Davis, local veterinarians, and others sampled 318 African village dogs from Uganda, Egypt, and Namibia.[3] There were some exceptions to the diversity in Namibia and Giza, which it was theorized was a result of European colonization or proximity to Eurasia.[4] They then looked at various breed and mixed-breed dogs and sent various physical information and blood samples to the Canine DNA Bank at the Baker Institute for Animal Health at the Cornell University College of Veterinary Medicine.[3] It was then discovered that African village dogs are "a mosaic of" indigenous dogs and non-native mixed-breed dogs.[3] The African village dog was about as closely related to the modern domestic dog as it was to the gray wolf.[5] Another reason the African village dogs have been found to be more genetically diverse is the lack of strict breeding, which narrows breeds' gene pools.[1]

Previous genetic studies of dogs have confirmed that the domestic dog traces its origins to Eurasian wolves 15,000 to 40,000 years ago.[3]

The information gathered from the Cornell study also suggests that breeds originally suspected to have come from Africa, such as the Pharaoh Hound and Rhodesian Ridgeback, have roots outside of Africa.[3] However, the results also indicate that African village dogs descend from indigenous ancestors that are related to the Basenji, a dog originating in the Congo Basin that has many unique traits.[6] The study also said that Afghan Hounds and Salukis appear to be indigenous to the Middle East.[7]

Domestication theory

Some of the African village dogs studied by Cornell University carried a genetic signature that was shared by Middle Eastern gray wolves.[5] This supported a theory by Robert Wayne and Bridgett vonHoldt of University of California, Los Angeles that domestication of dogs began in the Middle East.[5] Adam Boyko, the lead author of the study, said: "How the domestication process affects genetic diversity is poorly understood. We were interested in studying village dogs because we expected them to be the modern day dogs most similar to dogs that existed before man began to create breeds. Our study is unique because we are able to surmise whether specific village dog populations are more genetically similar to breed dogs or indigenous ancestral dogs."[6]

African village dogs became the close companion of people in Africa, beginning in North Africa and spreading south.[8] It quickly became the belief after Boyko's study that when Eurasian wolves—wolves that would later become African village dogs—migrated to Africa, they became domesticated long before East Asian wolves.[9] Robert Wayne, a professor at University of California, Los Angeles, said that "It's clear dogs did not originate in sub-Saharan Africa, since wolves are not native to that area", but North Africa was a possibility.[7]

While Boyko and his companion Carlos Bustamante did not think dogs originated in Africa, they did suggest that the conclusion of an East Asian origin did not have strong enough evidence.[2] Boyko said that while he did not rule out East Asia as a possibility, it was just as likely that domestication began somewhere else in Eurasia.[10] Boyko also suggested that dogs originated at some point between Africa and East Asia, such as the Caucasus Mountains, and split off from there.[11] After another study by Peter Savolainen, the pinpointed location, a region south of the Yangtze River, was reaffirmed to be the domestication origin of dogs.[2] The new study was not completely accepted. Boyko says that while the new work has stronger evidence to support Savolainen's theory, he would like to see even more genetic evidence.[12] Carles Vilà of the Biology Station of Doñana-CSIC says, "I do not think this is the last that we will hear of the time and place of the domestication of dogs."[2]

Behavior

Due to the effects of geography, gene flow barriers, and the presence of non-indigenous dogs in some packs, the African village dog has a complex social structure.[13]

See also

References

  1. 1 2 3 "African Village Dogs Are Genetically Much More Diverse Than Modern Breeds". ScienceDaily. 6 August 2009. Retrieved 6 May 2013.
  2. 1 2 3 4 Pennisi, Elizabeth (1 September 2009). "Study Reasserts East Asian Origin for Dogs". ScienceNOW. American Association for the Advancement of Science. Retrieved 22 May 2013.
  3. 1 2 3 4 5 Ramanujan, Krishna (3 August 2009). "African village dogs genetically unique from all breeds". Cornell Chronicle. Cornell University. Retrieved 6 May 2013.
  4. ↑ "Of Mutts and Men". National Science Foundation. 3 August 2009. Retrieved 22 May 2013.
  5. 1 2 3 retrieverman (31 January 2012). "African village dogs point to Middle Eastern wolves as the main source for the dog's genetic diversity". The Retriever, Dog, & Wildlife Blog. WordPress. Retrieved 7 May 2013.
  6. 1 2 Science Centric (4 August 2009). "Genetic study of African village dogs challenges the ancestral origins of several dog breeds". Science Centric. Science Centric. Retrieved 7 May 2013.
  7. 1 2 Viegas, Jennifer (3 August 2009). "Dog domestication likely started in N. Africa". DiscoveryNews. nbcnews.com. Retrieved 22 May 2013.
  8. ↑ Simpson, Professor MA (8 January 2013). "Dogs do come from Africa". health24. 24.com. Retrieved 13 May 2013.
  9. ↑ Newitz, Annalee (6 August 2009). "Were Africans The First People To Domesticate Dogs?". io9. Gawker Media. Retrieved 13 May 2013.
  10. ↑ Burns, Judith (3 August 2009). "Domestic dog origins challenged". BBC News. Retrieved 22 May 2013.
  11. ↑ Wade, Nicholas (3 August 2009). "Research Undermines Dog Domestication Theory". The New York Times. Retrieved 22 May 2013.
  12. ↑ Roach, John (4 September 2009). "Dogs First Tamed in China". National Geographic. Retrieved 22 May 2013.
  13. ↑ Byoko, Adam R.; et al. (18 August 2009). "Complex population structure in African village dogs and its implications for inferring dog domestication history". Proc Natl Acad Sci U S A. National Center for Biotechnology Information. 106 (33): 13903–13908. doi:10.1073/pnas.0902129106. PMC 2728993Freely accessible. PMID 19666600.
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