Within Canis, there are lots of bogus species proposed. A few years back, a team of researchers in Australia made some skull measurements of dingoes and decided that we should declare the dingo a new species distinct from the domestic dog and wolf. Never mind that every single genetic study on dingoes clearly puts them within the East Asian dog clade. A dingo is a feral dog very closely related to things like chow chows and akita inu.
Comparative morphology once declared the Japanese chin a distinct species, complete with their own genus, Dysodes. Never that such a thing wouldn’t pass the smell test now, it is still being tried on dingoes.
Within the genus Canis, there has always been a desire for some to split up species. Morphological variation is really great in the more wide-ranging species, but thus far, every proposed new species has come out lacking. Molecular techniques have discovered one species in this genus, the golden wolf of Africa, and there might be a distinct species of wolf in the Himalayas.
But all the rest have come up short. A recent study of wolf and dog genomes revealed that if you make dogs and dingoes a species, the entire species of Canis lupus becomes paraphyletic. So unless we want to abandon cladistics as our classification model, we pretty much have to keep dogs and dingoes within the wolf species. The red and Eastern wolves have also come up short in these studies,
And, I would argue, so has the coyote. Because coyotes split from wolves only very recently, I think a case can be made to classify them as Canis lupus latrans.
But that’s not where some people want to go. In fact, as of March this year, there was a paper that came out calling for classifying the Eastern coyote as Canis oriens.
I think this is quite unwise. For one thing, this ecomorph of coyote, which does have both wolf and domestic dog ancestry, is pretty new. Further, there is no evidence that this population is fully reproductively isolated from dogs, wolves, or the original Western coyote population. There might not be a lot of crossbreeding with domestic dogs.
But Western coyotes that are free of dog or wolf blood can still come into the East.There are no massive barriers that stop these coyotes mating with coyotes that might have wolf or dog in them.
Roland Kays, who was part of one of the original genome-wide studies of North American wolves, recently wrote a piece arguing against calling the Eastern coyote “a coywolf” or a distinct species. In the piece, Kays argues that this population of coyotes is not reproductively isolated, so it really is premature to call them a species now.
I would argue that the Eastern coyote is actually an ecomorph that is evolving to live in the human-dominated world that was once woodlands of Eastern North America, and an ecomorph is not a species. It could become one, but it takes quite a bit of time and isolation in order to do so.
In fact, I think the big take away from all the most recent study is that coyotes are a small type of wolf.
And that means that all this splitting we’ve done in Canis isn’t really all that helpful in understanding their exact biology and natural history.
That doesn’t mean there aren’t species of wild dog to be discovered. The case to split red foxes into two species is quite strong, and there is also a strong possibility that the gray foxes of the West and of the East are distinct species. The new species of wild dog will be found in creatures in like these, not in the larger dog species.
But Canis is where the charismatic dogs are. Wolves and their kin capture our imaginations. They are the closest relatives of the domestic dogs, and the domestic dog is descended from the Old World wolf. Within domestic dogs, we’ve been splitting them up into different varieties for thousands of years, and in the last two hundred, we’ve been doing so almost insanely. This has had to have had some effect, perhaps subconsciously, on how we view their closest relatives.
At one time, people used to go nuts naming things. Clinton Hart Merriam named dozens of species of bear in North America, which we now all recognize as belonging to one species. There is a herpetologist in Australia who does much the same thing with snakes and lizards in that country.
We live in a time when most of the larger fauna have become known to science. Pretty much the only way new species can be discovered is through trying to race molecular evolution. We don’t live in those times of gentlemen naturalists taking ships up the Congo River in search of new species of leopard.
We’ve just cataloged so much nature since that time. We don’t know it all, but we know a lot more than we did in 1880 or 1920.
And while I’d argue that the term “species” has to have a subjective element to it, it can’t be so subjective that it become squishy and useless.
And that’s unfortunately what we’re getting with things like Canis dingo and Canis oriens.
They really aren’t that much better than Dysodes pravus.
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