Thousands of years ago, American dogs mysteriously vanished

09 Juillet, 2018, 15:25 | Auteur: Yves Courtet
  • Thousands of years ago, American dogs mysteriously vanished

A new study out this week in Science seems to better illuminate one of these detours.

These dogs persisted for thousands of years in the Americas, but nearly completely vanished after European contact, the researchers found.

Dozens of researchers collaborated for the expansive study.

Scientists sequenced the genomes of ancient dogs using both mitochondrial DNA genes inherited from both parents, and mitochondrial DNA, genes passed from mothers to their offspring. Namely, that the first dogs came to the Americas more than 10,000 years ago, across the Bering land bridge, or Beringia, that connected North America and Asia.

Linderholm, who directs the BIG (bioarchaeology and genomics lab) at Texas A&M and who did much of the genome work, said, "The sudden disappearance of dogs in America was probably associated with European colonization, but we don't know the details yet".

The oldest evidence for dogs in the Western Hemisphere dates back about 10,000 years, some 6,500 years after the first humans arrived.

The new study dispelled a previous theory about the origin of dogs in the Americas, which posited that they evolved from domesticated wolves. Evidence that these dogs were used in sledding, along with suggestions that they were used for hunting and hauling, means that they could have facilitated the early settlement of the Americas.

A new study sheds light on the history of dogs and their role in human life, though many mysteries remain. Instead, they realized that the native dogs had virtually vanished.

It appears that native dog populations could have been wiped out through a number of causes, including disease, persecution and Europeans' desire to raise their own breeds.

Xiaomi's shares open 2.9% down on debut in Hong Kong
At midday, the stock staged a recovery from HK$16 (£1.53) to HK$16.96 but was still below its debut price of HK$17. That is far short of the oversubscription rates for other tech IPOs in Hong Kong.

Thaïlande : 4 des 12 enfants de la grotte déjà évacués
Les garçons sont prêts à affronter tous les défis", dit le chef de la cellule de crise. Pour effectuer cette mission, treize spécialistes en spéléologie ont été dépêchés.

Les NTIC : avantages et inconvénients
En effet, avoir mille et une tâches à accomplir à la fois, ça peut avoir des effets négatifs. En effet, les travailleurs effectuent les tâches beaucoup plus rapidement tout en conservant leur qualité de vie.

While some American dogs might have been wiped out by epidemics or purposefully killed by Europeans, as indigenous people often were, there are likely other reasons for their demise. Did they intermix with dogs brought by European settlers? Pre-contact dogs were present as the first travellers journeyed from Siberia into the Americas and began to thrive.

In a paper published Thursday in Science, an worldwide team of archaeologists and geneticists report that.

"The picture is not as clear as they want it to be", Peter Savolainen, an associate professor in Evolutionary Genetics at the Royal Institute of Technology in Stockholm, told Gizmodo.

The researchers analyzed genetic material from 71 "pre-contact" dogs, whose remains spanned 9,000 years, and compared it with the DNA of 145 modern dogs.

Dog DNA taken from other ancient sites in the Americas not included in the study has also been found to have more similarities with the chihuahua and other South American breeds than this study did.

Oddly enough, scientists found that the closest surviving trace of pre-contact dogs' DNA is found in a sexually transmitted canine cancer.

The closest detectable extant lineage to pre-contact American dogs is the canine transmissible venereal tumour, a contagious cancer clone derived from an individual dog that lived up to 8,000 years ago.

"It is fascinating that a population of dogs that inhabited many parts of the Americas for thousands of years, and that was an integral part of so many Native American cultures, could have disappeared so rapidly", senior lead author Laurent Frantz, a lecturer at Queen Mary University and co-investigator at the University of Oxford, said. But its DNA contains no trace of ancient dog DNA.



Fils de légende de la Formule 1 a dépassé son père
Nul doute qu’elle offrira à Mika la meilleure option pour poursuivre sa carrière dans le sport automobile. Et il n'est pas Andrei Arshavin, pour répondre à la question sur les attentes facilement et naturellement.

La FIFA colle un avertissement à Vida — Croatie
Des parlementaires russes ont demandé à la Fifa des sanctions sévères contre la Croatie. Cela fait en effet plusieurs années que l'Ukraine et la Russie sont en conflit ouvert.

Enquête pour meurtre après le décès d'une femme empoisonnée au Novitchok — GB
Mme Sturgess et son compagnon auraient manipulé un objet contaminé , avancent les autorités. La police n'a pas pu établir si le Novitchok provenait du même lot dans les deux cas.

Brazilian International Paulinho Returns to Guangzhou Evergrande After One Season With Barcelona
Paulinho rose to prominence in his homeland for Sao Paulo-based Corinthians before he moved to Tottenham in 2013. He scored nine goals in 34 La Liga appearances for the Catalan giants last season.

Vettel beats Hamilton in Silverstone classic
Raikkonen, who completed the podium for Ferrari , was handed a 10-second penalty for the early incident involving Hamilton. Both spun and rejoined, Hamilton after running off track. "I will not give up, believe me, I will not give up.

England sets India 199 to win series-decider 3rd T20
Hopefully we can learn as we go along. "That total isn't defendable when a guy comes out and plays like that on a small ground. However, preserving that impressive record will require India to find their best form against a resurgent England .

England will wear white for World Cup semi-final with Croatia
Will Harry Kane lead England to World Cup glory? That year the Soviets finished in fourth place at the 1966 World Cup . England football fans are scrambling to buy tickets for the country's first World Cup semi-final for nearly 30 years.

Dele, Maguire head England into first semi-final in 28 years
And while both teams , drinking side-by-side, were civil enough during the game. It's been a long time between drinks for England football fans.

Espagne : Fernando Hierro quitte le poste de sélectionneur
Directeur sportif de la Fédération avant la Coupe du Monde en Russie, Hierro n'a pas souhaité reprendre ce poste. Hierro "est en quête de nouveaux horizons et veut relever de nouveaux défis professionnels." .

Pride of lions kill suspected rhino poachers on game preserve
Nine rhinos were killed by poachers in Eastern Cape province, where the reserve is located, this year alone. Lions have mauled to death suspected poachers who entered a South African wildlife reserve to kill rhinos.