Dogs: A Study Pointing to the Origin of Domestication – 07/16/2022 – Science

An unprecedented survey of the genetic diversity that existed among wolves at the end of the Ice Age has shed more light on the origins of the long love story between dogs and humans.

The data suggests that most dogs living today are closely related to ancient wolves that lived in eastern Eurasia, in places such as Siberia, although other groups of this species apparently contributed to the ancestors of today’s domestic animals.

Results, Recently published in the British scientific journal NatureIt does not completely solve the mystery of dog domestication, but it does bring a great deal of new information on the subject.

“The data set for the article is very impressive. We have about 70 genomes sequenced. [ou seja, ‘soletrados’ na íntegra, como o genoma humano atual] Over a time series of 100,000 years. This allowed us to analyze a tremendous amount of detail about how wolves evolved during this period. One aspect of this, of course, is their relationship to domesticated dogs, David Stanton, a researcher at the Center for Paleobiology at Queen Mary University of London, explains in an official statement.

He is one of the co-authors of the study, which was conducted by an international team of dozens of scientists, mostly Europeans.

Wolves thousands or tens of thousands of years old that have “donated” their DNA for study have a wide geographical distribution. Their skeletons come from most of Western Europe, Russia, the Middle East, Central Asia, and North America.

In fact, wolves were one of the most widespread types of large mammals on the planet in the Ice Age (Ice Age), at which time they resembled humans who eventually domesticated some of them. This geographical distribution, a sign of great diversity, may help explain the fact that the animals did not disappear at the end of this period, unlike many other predators of the Pleistocene, such as Bears Cave And Saber.

“It’s amazing how quickly and easily they were able to move relatively quickly and easily across so many areas,” Stanton noted in an official statement.

Another potential key factor was revealed by genetic analysis: the frequent association between wolf populations over time. Clearly, breeding involving different groups of species was an effective “wireless telephone”, carrying new mutations in DNA from one corner of the Northern Hemisphere to another, especially if they occurred in Siberia.

It appears that Siberia was the place where most of the wolf genes were “exported” to wolf populations elsewhere on the planet. With this facility for mixing and incorporating genetic novelties, animals may have increased their ability to adapt to new environmental challenges over time.

The situation seems to have changed for wolves from 10,000 years before the present, a time when agriculture and animal husbandry began in many parts of the world, with increasing human population density. This could mean that from that moment on, members of our species caused environmental changes that reduced the space available for wolf packs and prevented them from continuing to contact each other.

Genomic data also suggests that the ancestors of dogs alive today were still part of a single “large family” with wolves, at least as far as DNA is concerned, 28,000 years ago. This may be the date the domestication process began, which means that dogs came to live with humans about 20,000 years earlier than any other animal. However, the new study’s authors note that the process may have begun before that time.

A more detailed comparison of ancient wolves to modern members of their species and dogs revealed that no number of current wolves match the possible ancestors of domestic dogs. Dogs are generally akin to wolves that were found in eastern Eurasia at the end of the Ice Age. But dogs from the Middle East and Africa derive up to half of their DNA from other ancient wolves, akin to those inhabiting the western part of Eurasia today.

This may indicate that dogs were domesticated twice, in the east and west, or that only eastern domestication took place, to which interbreeding was added later with western wolves (since crosses between wolves and dogs are relatively common). It is not yet possible to determine which of the two scenarios is most likely.