Anthropology

as clades of the same biological Family in the Animal Kingdom classifications. Dogs are descended from wolves. So inter breeding between them is not so unusual. They have not been separated long enough, with enough mutations, to make it impossible for them to mate with each other. However, some dog breeds are more capable of inter breeding with wolves than others. I could see a German shepherd or Alaskan Malamute mating with a wolf, but not a Chihauhua.

https://en.wikipedia.org/wiki/Canidae

From what you picked up from the article, it looks like there are differing views about whether the "new" species is actually a separate species. Or, perhaps they are a subset, or clade of Denisovan.

Maybe there is still a trace of large headed Denisovans among us, modified by intermating and evolution. Some modern people whose bodies are proportional in every other way have larger than average heads.

Extinct species in our ancestry are extinct as a separately identifiable species today, but are still with us in the traits that they contributed which remain. We are still upright and bipedal, like Homo Erectus, but standing straighter. We don't have the occipital bun of Neanderthal, but some modern people still have a noticeable brow ridge and deep set eyes. We also have genetic mutations from Neanderthal that influence allergies and viral infections. We still have a lot in common with chimp DNA and even in some behavioral traits that we share with them.