I keep having comments that fit other threads better (this one would be the reading one - but it would rather have to be a "have read" thread …)
Anyway, I own several
books about
wolves by several
authors; fascinating
creatures, absolute top predators whose absence can really mess up some ecosystems. And it's no wonder that Canis lupus and Homo "sapiens" struck it off - after a long pre-adaptation on the canine side. Both are highly social creatures - with the wolves on average being far
less antisocial.
Anyway, there were several black wolves shown in the video. This melanism seems to be restricted to North America (timber wolves), and must be caused by some inbreeding of some Canis (lupus) familiaris genes into the North American wolf gene-pool, as in a "pure" wolf genome the allele, or more likely mutation, is absent.
At the other end of the color spectrum are
the white arctic wolves, who have gone the way of the arctic fox to a degree - fur color change included (which is something the polar bear dispenses with). But they definitely hang tough in some of the most adverse climate on the planet - north of natural Inuit habitation, even.
Size-wise, the smallest wolves are "Mowgli's family" from Rudyard Kipling's "Jungle Book." I believe I once saw a zoo pack in the Berlin zoo (one of the two - or is it three? - zoos there). Depending on which subspecies it was, these may be as small as weighing 25 kilograms, or 55 pounds. Back in the early 1970s, my family had a Boxer female (from a large breed strain, admittedly) who weighed 35 kilograms or 77 pounds full grown. We decided on a female after meeting dad, a strapping 50 kilograms or 110 pounds (as were our female's brothers). That said, C. lupus is, pound for pound, far and away the toughest and hardiest of the Canis "clan" (I'm not a cladistics or taxonomy nerd by anyone's definition). As Konrad Lorenz, the Austrian zoologist and 1973 Nobel Prize winner in Physiology or Medicine once put it, "the size of a Great Dane (actually a German breed, "Deutsche Dogge") combined with the hard muscles of a wire-haired Fox Terrier!"