Veeramah in a release accompanying the study. In fact, at least one study has suggested that dogs could have been domesticated more than once. Researchers analyzed mitochondrial DNA sequences from remains of 59 European dogs aged 3, to 14, years , and the full genome of a 4,year-old dog that was buried beneath the prehistoric mound monument at Newgrange, Ireland. Comparing these genomes with many wolves and modern dog breeds suggested that dogs were domesticated in Asia, at least 14, years ago, and their lineages split some 14, to 6, years ago into East Asian and Western Eurasian dogs.
The many interbreedings of dogs and wolves also muddy the genetic waters, of course. Such events happen to the present day—even when the dogs in question are supposed to be stopping the wolves from eating livestock.
Perhaps more intriguing then exactly when or where dogs became domesticated is the question of how. Was it really the result of a solitary hunter befriending an injured wolf? One similar theory argues that early humans somehow captured wolf pups, kept them as pets, and gradually domesticated them. This could have happened around the same time as the rise of agriculture, about 10, years ago. The oldest fossils generally agreed to be domestic dogs date to about 14, years, but several disputed fossils more than twice that age may also be dogs or at least their no longer entirely wolf ancestors.
Since more recent genetic studies suggest that the date of domestication occurred far earlier, a different theory has gained the support of many scientists. But, Hare notes, the physical changes that appeared in dogs over time, including splotchy coats, curly tails, and floppy ears, follow a pattern of a process known as self-domestication.
Some partner instead with customs officials searching for contraband, from drugs to elephant ivory. Still others lead the way tracking down poachers , patrolling cargo ships for rats that might escape at distant harbors, or exposing forest insect pests in shipments of wood from abroad. They guide deaf and blind people, and they help people with autism and post-traumatic stress disorder manage with anxiety.
Most dogs are a mix of breeds—in , one study estimated that only 5 percent of dogs in shelters are purebred. Just as dogs come in all sizes, shapes, and colors, these animals also come in a spectrum of temperaments.
A bulldog might look fierce but be cuddly as a kitten, whereas a cute cocker spaniel might nip at your finger without thinking twice. This is why animal handling expert Jack Hanna recommends teaching children to always exercise caution around a dog they do not know. The point is it can happen. Of course, when dogs are cared for properly and treated with respect, they can be incredibly loving, playful, and intelligent companions.
After all, the yipping and tail-wagging your dog performs when you grab a bag of treats are carry-overs from when its ancestors needed to communicate with other members of its social group.
Chasing sticks and balls may be linked to the pursuit of prey, while digging at the carpet or a dog bed echoes how a wild canid would prepare its sleeping area. Editor's note: Bringing a dog into your household is a major responsibility. More than 1. All rights reserved. Common Name: Domestic dogs. Scientific Name: Canis familiaris. Type: Mammals. Diet: Omnivore. Group Name: Pack. Latvia - Latvija.
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United States. For Dogs. For Cats. About Hill's. Media Press Releases Media Kit. Other Careers. Published by. Establishing a Dog Breed It's a fairly long road for a new type of dog to become an established breed. But after decades of dogged effort, he and his fellow scientists are still arguing about the answers. They agree that all dogs, from low-slung corgis to towering mastiffs, are the tame descendants of wild ancestral wolves.
But everything else is up for grabs. Some say wolves were domesticated around 10, years ago, while others say 30, Some think early human hunter-gatherers actively tamed and bred wolves. Others say wolves domesticated themselves, by scavenging the carcasses left by human hunters, or loitering around campfires, growing tamer with each generation until they became permanent companions.
The only way of doing so is to look into the past. Larson, who is fast-talking, eminently likable, and grounded in both archaeology and genetics, has been gathering fossils and collaborators in an attempt to yank the DNA out of as many dog and wolf fossils as he can. Those sequences will show exactly how the ancient canines relate to each other and to modern pooches. And already, they have yielded a surprising discovery that could radically reframe the debate around dog domestication, so that the big question is no longer when it happened, or where, but how many times.
On the eastern edge of Ireland lies Newgrange, a 4,year-old monument that predates Stonehenge and the pyramids of Giza. Beneath its large circular mound and within its underground chambers lie many fragments of animal bones. Press your finger behind your ear.
And indeed, Bradley found DNA galore within the bone, enough to sequence the full genome of the long-dead dog. Larson and his colleague Laurent Frantz then compared the Newgrange sequences with those of almost modern dogs, and built a family tree that revealed the relationships between these individuals.
To their surprise, that tree had an obvious fork in its trunk—a deep divide between two doggie dynasties. One includes all the dogs from eastern Eurasia, such as Shar Peis and Tibetan mastiffs. The other includes all the western Eurasian breeds, and the Newgrange dog. The genomes of the dogs from the western branch suggest that they went through a population bottleneck—a dramatic dwindling of numbers. Larson interprets this as evidence of a long migration.
He thinks that the two dog lineages began as a single population in the east, before one branch broke off and headed west. This supports the idea that dogs were domesticated somewhere in China. The team calculated that the two dog dynasties split from each other between 6, and 14, years ago. But the oldest dog fossils in both western and eastern Eurasia are older than that. Which means that when those eastern dogs migrated west into Europe, there were already dogs there.
To Larson, these details only make sense if dogs were domesticated twice.
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