قالب وردپرس درنا توس
Home / Science / The ferocious wolves are not wolves at all, they form a distinct blood line with jack wolves.

The ferocious wolves are not wolves at all, they form a distinct blood line with jack wolves.



The two canine skeletons face each other.

The ferocious wolves became famous because of their haunts game of Thrones, They are portrayed as larger versions of more common wolves. In the real world, only today’s largest wolf pack is as big as a wild wolf weighing 70 kilograms. These animals were once shared with predators like the North American elephant-nose dragon (a saber-toothed cat). Before the arrival of humans, terrible wolves were more common than ordinary wolves, as the wreck found in the La Brea tar leak showed, there were 1

00 times more gray wolves than gray wolves.

Like a runny nose and many other large North American mammals, this terrifying wolf disappeared when the gray wolves and coyotes survived, during climate change and humans’ arrival on the African continent. As they left, they left a mystery: What are they?

A new study uses ancient DNA from scary wolf skeletons to determine that they are not actually wolves and have been genetically separated from them for millions of years.

It looks like a wolf, but…

When it comes to canines, species boundaries and their relationship with anatomy are blurred. Domesticated dogs have an incredible variety of forms, but they are all part of the same species and can still cross with their derived gray wolves. Gray wolves and coyotes can also cross. Therefore, as their similar appearance implies, the question of whether gray wolves and ferocious wolves are closely related will also imply whether ferocious wolves have made genetic contributions to any current species.

This new work done by a large international cooperative organization (full disclosure: I used to climb with an author) began with an attempt to answer the traditional method of answering this question: observing the skeleton of a fierce wolf. However, this analysis involving more than 700 individual bones did not yield much. Although the differences between them are sufficient to enable the two species to be identified consistently, there is no obvious difference that indicates a great evolutionary distance.

Therefore, the team turned to a more modern approach. Fragments of collagen can be separated, collagen is the main component of bone, and there are often subtle differences between species. The sequence of wolf wolf collagen is sufficiently different, indicating that wolf wolf is closely related to many other modern canine-like species. But the similarity between them is very high enough to prevent researchers from solving the relationship between these species.

Next, the research team began to isolate DNA from the remains and managed to obtain some samples from five samples from all over the United States, from Idaho to Tennessee. The age of the bones ranges from 13,000 to more than 50,000 years. The analysis of the shorter mitochondrial genome is similar to collagen. It shows that terrible wolves are a unique lineage far from wolves and coyotes, but the analysis is confusing due to subtle differences between species and the fact that certain lineages (such as wolves and coyotes) mate.

Distant relative

The rest of the analysis depends on the sequence of the conventional nuclear genome. Due to the age of the sample, the DNA was severely damaged and only a small part of the complete genome of the animal was produced (depending on the sample, only 1% to 20% of the genome can be obtained). In order to fully explore the canine lineage, the researchers also obtained genome sequences from the North American wolf and two jack wolves, and most other species on this branch of the evolutionary tree have been sequenced.

Trees based on these sequences indicate that the last fox species diverged from the rest of the canines about 7 million years ago. The next branch occurred about 6 million years ago, resulting in a branch containing both jack wolf species and wild wolves. All other things, including African wild dogs, all kinds of wolves and coyotes, are located on separate branches of bloodlines, and are far more connected to each other than wolves.

As usual in evolutionary sequence analysis, there is considerable uncertainty. The split between the terrible wolf and other main branches may have occurred between 4 and 8 million years ago. But it is clear that despite their biological similarities, wolves are part of a unique bloodline closely related to dogs.

Considering that other canines seem to be involved in semi-regular crosses, the researchers checked for signs here. The analysis shows that despite the thousands of years of sharing a continent, there is no clear indication that a terrifying wolf has crossed with a wolf or a coyote. There are signs that the terrible wolf ancestor crossed with the ancestors of wolves, coyotes, and black holes about three million years ago, but this signal is weak.

Overall, this result is interesting in itself.generations Dungeons and Dragons The player may have been told that the terrible wolf is a real big wolf, and we now know that this is wrong. But it may also cause us to look back and rethink the fossils we have owned for many years. We obtained some numbers from North America, and the explanation for these numbers is that all the canines on the continent are part of a cluster of closely related species. Now that we know that there are two very different lineages here, we can go back and determine whether any older fossils are more closely related to one or the other lineage.

Naturally, 2021. DOI: 10.1038 / s41586-020-03082-x (about DOI).


Source link