What is a wolf, anyway?


Science magazine says The legendary dire wolf may not have been a wolf at all, while the actual article published in Nature says only Dire wolves were the last of an ancient New World canid lineage, and says that grey wolves and dire wolves are not as closely related as previously thought.

Dire wolves are considered to be one of the most common and widespread large carnivores in Pleistocene America1, yet relatively little is known about their evolution or extinction. Here, to reconstruct the evolutionary history of dire wolves, we sequenced five genomes from sub-fossil remains dating from 13,000 to more than 50,000 years ago. Our results indicate that although they were similar morphologically to the extant grey wolf, dire wolves were a highly divergent lineage that split from living canids around 5.7 million years ago. In contrast to numerous examples of hybridization across Canidae, there is no evidence for gene flow between dire wolves and either North American grey wolves or coyotes. This suggests that dire wolves evolved in isolation from the Pleistocene ancestors of these species. Our results also support an early New World origin of dire wolves, while the ancestors of grey wolves, coyotes and dholes evolved in Eurasia and colonized North America only relatively recently.

OK, then, what is a wolf? If we saw a large canine that hunted in packs nowadays, wouldn’t we call it a wolf, while recognizing that it could be distinguished scientifically as a different species? What does “closely related” even mean?

I looked at the results.

Just to put it into context. if dire wolves and grey wolves diverged less than 6 million years ago, that means their relationship is comparable to that of modern humans and chimpanzees, which diverged about 6 million years ago, too. Meanwhile, the various local house spiders I study diverged 50-100 million years ago. Would we have an article declaring that chimpanzees aren’t apes? I don’t think so.

Dire wolves were wolves. They’re a distinct lineage with an interesting history, but I’m not particularly interested in arguing about whether certain colloquial terms or folk taxonomy are appropriate.

Comments

  1. says

    I dunno PZ, it looks like they are more closely related to foxes and jackals than to the animals called wolves. It would be more accurate to say that coyotes are wolves (and they do in fact interbreed); but it’s a vernacular term in any case. Whether you want to say that humans are apes, or humans are cousins of apes, is basically arbitrary. In this case, dire wolves are more distantly related to wolves per se than they are to other species of dogs that aren’t called wolves. So I don’t see why it’s wrong to say that they aren’t wolves after all.

  2. Morgan says

    If chimpanzees were extinct, and there were a bunch of extant non-human species more closely related to us than chimps, called things like “elves” and “orcs”, and someone found paleontological evidence of chimps, wouldn’t it be reasonable to say that “dire human” was a misleading name to give them?

    I’m not particularly interested in arguing about whether certain colloquial terms or folk taxonomy are appropriate.

    …Isn’t that exactly what this post is?

  3. weylguy says

    I can’t wait for geneticists to come up with a mixed dire wolf-dog breed that I can threaten my neighbors with.

  4. Bruce says

    While one could define a wolf as anything within the divergences of the last 2.5 million years, it looks more sensible to me to define a wolf as anything from that group in the last 7-10 million years. That would make jackets and the Andean Fox also be wolves. But not the European Fox.

    I think sensible Clade naming is based on grouping everything with a common ancestor to a certain age. But the labeling of the clade should be done by the traditions of biology, where they fit it. That’s why fish isn’t a clade.

  5. lasius says

    That paper is very interesting as we now finally have good aDNA data of Canis….I mean Aenocyon dirus. And it is an interesting and unexpected result that they seem to be the sister taxon to all lving Canini, which does in fact mean, that they are not wolves. Can’t find a fault with that.

  6. PaulBC says

    They overlapped somewhat with humans, so you could speculate about what those people called dire wolves as opposed to gray wolves. Unfortunately, there’s no written record and no way to know (that I can think of).

  7. chris61 says

    Since none of us are likely to run into one out in the woods, I’m on the side of cleaning up the taxonomy.

  8. kingoftown says

    @9 Rob Grigjanis
    When it’s a killer “whale” or a porpoise.

    Lots of common names, like toad or moth, have no taxonomic meaning and when more distantly related animals like the maned wolf get called wolves, I see no problem calling the dire wolf a wolf.

  9. PaulBC says

    Also mahi-mahi is sometimes called a dolphinfish, and I remember being confused a long time ago by an illustrated kid’s encyclopedia where it was referred to simply as “dolphin.” (At least some kind of fish, and I am backfitting when I say it must have been mahi-mahi.)

  10. Rob Grigjanis says

    kingoftown @14: Or river dolphins? We often give common names which reflect appearance and behaviour rather than ancestry. Nowt wrong with that.

  11. blf says

    They overlapped somewhat with humans, so you could speculate about what those people called dire wolves as opposed to gray wolves.

    Presumably, both wolves called people “lunch”.

  12. cartomancer says

    Perhaps we should just compromise and say that it is a wolf, but not a very good one. A dire one, in fact.

  13. hemidactylus says

    Since bears aren’t much more than oversize dogs, has anyone thought of doing a long-running breeding experiment with grizzlies, as had been done with foxes in Russia? What could go wrong?

    We could in short time have flop eared piebald grizzlies trained to roll over and fetch the paper.

  14. PaulBC says

    hemidactylus@28 I’d learned never to begin such undertakings without the advice of a trained chaotician. What does Jeff Goldblum charge for his services these days?

  15. blf says

    @28, There are at least two experiments in Russia, both started by the same man (Dmitry Belyayev): The famous silver fox experiment (breeding for tameness (broadly speaking)), and later, breeding rats for aggressiveness (broadly speaking). Both experiments are, as far as I am aware, still ongoing. The rats are now so aggressive that (from memory) they have to be separately caged in reinforced cages, kept in a locked room. No-one may enter the room alone (there must always be a second person present). Chain-mail gloves are required when opening the cages or handling the rats.

    Anyways, it occurs to me we already have a (uncontrolled) replication of the aggressive rat experiment: Trump supporters.

  16. Rob Grigjanis says

    hemidactylus @28:

    has anyone thought of doing a long-running breeding experiment with grizzlies, as had been done with foxes in Russia?

    Caniformia dreamin’
    On such a winter’s day

  17. hemidactylus says

    I wonder how long before we’d get to poodle and Pomeranian grizzlies. Or the great dane of grizzlies. That’s a huge kibble bill. Or mysterious disappearances of owners.

    @30- Rat supersoldiers? Sentry rats protecting a perimeter?

  18. unclefrogy says

    I do not understand what the distinction they are making is. Are they just saying that the modern wolf is not descendant from the Dire wolf? That is interesting, but saying they are not wolves is poor writing in my opinion a little inflating the story maybe? Not like they are saying they are really cats or bears of\r weasels or something.
    uncle frogy

  19. PaulBC says

    The only scientific solution is to restore them from DNA, release them into populated areas and find out what people cry as they’re running away.

  20. nomdeplume says

    @38 The distinction they are making is that the Dire Wolf is not a part of the Grey Wolf group of species thought of as typical wolves, but are more closely related to jackals, though perhaps with the implication that they have convergently evolved into active hunters like the Grey Wolf from scavengers like Jackals. Seem fine to me in spite of PZ’s muddying the waters with Chimpanzees.

  21. mailliw says

    @31 Stroppy

    Bears discover libertarians. Perform experiments.

    the right of the people to keep and arm bears, shall not be infringed

  22. mailliw says

    @28 Hemidactylus

    Since bears aren’t much more than oversize dogs, has anyone thought of doing a long-running breeding experiment with grizzlies

    There have been attempts, but many of the crossbred bears were very temperamental, suffering from extreme mood swings and had to be reclassified as bipolar bears.

  23. PaulBC says

    There have been attempts, but many of the crossbred bears were very temperamental

    Are they related to Gladly the cross-eyed bear?

  24. Anton Mates says

    OK, then, what is a wolf? If we saw a large canine that hunted in packs nowadays, wouldn’t we call it a wolf, while recognizing that it could be distinguished scientifically as a different species?

    No, in general we wouldn’t. Feral domestic dogs, dingoes, African wild dogs, and dholes are all pack hunters that overlap with grey wolves in size, but we don’t usually call them wolves.

    “Wolf” in the narrow sense refers to the non-domesticated lineages of Canis lupus, the grey wolf. More broadly, you might include extremely close relatives like red wolves and African golden wolves, but that’s about it. Of course many other species have “wolf” in their common name, from maned wolves to marsupial wolves, but that just means someone thought they looked vaguely doggy.

    What does “closely related” even mean?

    In this context? Close enough to hybridize, pretty much.

    All the animals we’re talking about are part of the subtribe Canina, the “wolf-like canines.” Within this group, most of the genus Canis (or possibly all of it, once they finish revising) forms a single species complex. Grey/red/ African/Ethiopian wolves, coyotes, golden jackals, domestic dogs, dingoes, New Guinea singing dogs…all these critters can interbreed, and there’s been a lot of recent gene flow between their populations.

    Dholes, African wild dogs, and black-backed and side-striped jackals are more distantly related; they’re also members of Canina, but they don’t interbreed with the Canis complex so far as we know.

    We thought dire wolves were part of the Canis complex, but it looks like they’re actually basal to the entire Canina group. Their superficial resemblance to grey wolves is a matter of convergent evolution; the common ancestor of both lineages was probably a smaller, jackal-like animal.

    if dire wolves and grey wolves diverged less than 6 million years ago, that means their relationship is comparable to that of modern humans and chimpanzees, which diverged about 6 million years ago,

    That doesn’t follow; canids have much shorter generation times than hominids, so we’re talking 4-5 times as many generations of the former within that period.

    In any case, the point is that dire wolves and grey wolves aren’t as close as, say, modern humans and Neanderthals, which is what we used to believe.

  25. KG says

    Anton Mates@47,

    African wild dogs are also called “painted wolves”. But don’t really look either doglike or wolflike – less so than foxes, I’d say. Of course that doesn’t tell us how closely they are related to the grey wolf, which presumably the genetics does.