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Archive for the ‘wild dogs’ Category

black coyote

For most of my life, scientists believed that the present era was still the Holocene.  Glaciers retreated with a global warming trend around 11, 650. Man went from being the apex predator over much of the world and became the apex consumer. Agriculture allowed our populations to expand, and we started to give up our wandering ways and became “civilized.”

It was generally believed that the past few centuries are but a continuation of this age, but now a growing number of scientists believe we have left the Holocene and entered into the Anthropocene. Several scholars have issues with this new distinction, but I think it is quite useful. In this era, human activity is the main factor affecting climate and ecology, which is why the age is named for the Greek word for human (anthropos).

The best argument I’ve seen for when this era began is 1610.  In this scenario, the era is dated to when European disease and conquest killed off enough Native Americans and enslaved and enough African had been enslaved to allow forests to grow back in former agrarian fields.  This process started in 1492, but by 1610, enough of those trees had grown to remove enough carbon dioxide from the atmosphere to push the planet into the Little Ice Age.

Darcy Morey and Rujana Jeger have a great model for understanding dog domestication as a change in trophic strategies.  In the Pleistocene ecosystems, most wolves were mesopredators, playing second fiddle to an ecosystem full of cave lions, machairodonts, large bears, and cave hyenas. When these wolves hooked up with people, though, they hitched their wagon to the species that often behaved as the apex predators in the ecosystems.  When humans switched to agrarian lifestyles during the Holocene, humans became apex consumers, and dogs joined us as beneficiaries of being allied to that apex consumer species.  During the Holocene, many wolves became apex predators, as the cave lions and other large predators became extinct.

I’ve always liked the framework that Morey and Jeger derived in this paper, but now that we’re entering into a new geological age, maybe we need to look at the change in trophic strategies of wolves in this new age.

Morey and Jeger don’t have a good framework for what happened to wolves in the Anthropocene, but across Eurasia and North America, wolves were gone from many human-dominated landscapes by the first decades of the twentieth century.  They existed only in isolated areas in Western Europe, and in the  lower 48 states of the US, they lived only in Minnesota and in an isolated region in East Texas and Louisiana, where the taxonomically controversially red wolves were located.

Large pack-hunting wolves were really in quite a bit of trouble.  In the United States, the coyote population began to expand out of its Western core range into the Great Lakes States. They eventually made to New England and the Maritimes of Canada, and they hybridized with relict wolves and the expanding population of domestic dogs.  Coyotes eventually colonized all the Eastern states, and as they did so, they largely became the apex predators in many parts of their range.

But in the 1960s, attitudes about wolves began to change. Many nations protected wolves, and there were often introduction plans in the works.  By the early decades of the twenty-first century, wolves were making significant comebacks in Germany and Italy. The wolves in Italy were often living very much like stray domestic dogs, living large at garbage dumps. Wolves live near large cities in Germany, and how these wolves are going to adapt to living in such human dominated environments is going to be a major question for researchers.

And in throughout Eurasia, we began to see that domestic dogs were mating with wolves.  Indeed, it is now estimated that a majority of wolves in Eurasia have relatively recent dog ancestry. 

Similarly, as coyotes expanded in North America, their genes began to work their way into the wolf population.  Yes, coyotes in a large part of the US have wolf ancestry, but we also have discovered that wolves across North America have coyote ancestry. Indeed, one interesting thing about these genome comparisons is that coyotes and wolves are much more closely related than we initially gleaned form mitochondrial DNA analysis. The calculation is that the gray wolf and the coyote last shared a common ancestor around 50,000 years ago.  This recent common ancestry has a taxonomic implication, which is that coyotes are themselves a divergent form of gray wolf in much the same way domestic dogs are.

In the Anthropocene, the wolves that have done the best have been the domestic dog and the coyote. The domestic dog’s ability to ingratiate itself into human society or live very nicely as an opportunistic scavenger/hunter on the periphery of humanity is a great gift.  The coyote can live as an opportunistic scavenger/hunter as well, and it also can live very nicely as a mousing fox or pack up and hunt deer.

Gene flow among wolves, coyotes, and dogs has made these entities much more fuzzy than we once thought they were. Dog genes are working their way into both the coyote and wolf population.  Strange pelt colors are popping up in the wild animals. The black coloration in domestic dogs was conferred onto the North American wolf population during the Holocene, but this same mutation for melanism has entered the coyote and Italian wolf population in very recent years. Dogs have introduced dewclaws on the hindlegs to some wolf populations, and I have seen photos of Eastern coyotes that have those hind dewclaws as well, which likely were introduced through breeding with domestic dogs.

Coyotes in the East are evolving larger size to become better predators of deer, but becoming larger and more effective ungulate hunters will have a trade-off. As carnivorous mammals grow larger, they become more and more dependent upon large prey to survive.  Very large wolf-like coyotes will lose their ability to live well on small prey and garbage.

So in the Anthropocene, dogs remain allied to the apex consumers. Some coyotes operate as apex predators, and some wolves live as opportunistic scavengers.

And as these creatures adjust their trophic strategies in a much more predator tolerant world, the pseudo species barriers that exist among wolves, coyotes, and dogs can break down. Hybridization among these creatures is likely to be a major feature of their continued evolution, a definite feature and not a bug.

These canids  thus make the leap with us into this human dominated age, an age that is experiencing a mass extinction of amphibians and great retrenchment of large sharks and big cats.

Yet they are still there. Evolving as the winds change. Winds that we ourselves are changing and are only now starting to understand.

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african wild dog dentition

These are the teeth of an African wild dog or painted wolf that has been tranquilized.

One thing you might notice is all the extra cutting edges around the carnassial teeth.  These extra blades make it easier for them to bite into the meat of their kills and bolt down the food quickly before lions and hyenas show up to rob them.

Dholes, the closest living relative of the African wild dog, also have similar carnassials, as does the bush dog. This feature evolved in parallel in bush dogs,  but for a while, they were often classified with the dhole and African wild dog.

We now know that the bush dog is within the “South American clade” of wild dogs. Its closest relative is the maned wolf.

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painted wolves

I’ve been watching Dynasties on BBC America, and I have been waiting until the series got to the African wild dog episode. African wild dogs, which the series calls “painted wolves” in light of a direct translation of their scientific name,  Lycaon pictus,  are critically endangered canids.  Only 6,600 of them exist in the wild, and the series hooked up with Painted Dog Conservation to follow the high drama of two packs living at the Mana Pools National Park in Zimbabwe.

The story starts with a pack led by Tait. Tait is a ten-year-old breeding female, and she has over 200 descendants. One of these is Blacktip, the breeding female of growing pack, that now needs more territory to feed itself. Tait’s pack is in a pretty bad state.  Their numbers are small, and because the African wild dog range in the park is surrounded on two sides by lion and spotted hyenas, Blacktip’s pack drives Tait’s pack from its territory.

Tait’s family escapes to lion country, where they are forced to hunt impalas, choke down some bits of meat, and then run like hell when the lions eventually show up.  Blacktip’s pack lives very nicely, but they are forced to remain stationary while Blacktip nurses her pups.  When they get old enough to move, Blacktip leads her pack against her mother in lion country,  a campaign that will prove disastrous.

Spotted hyenas kill at least one pup, and lions almost off the rest of the litter. However, they are saved when a foolish African buffalo comes charging onto the scene.  The buffalo was unexpected,  but the lions hate buffalo more than they hate African wild dogs– and certainly prefer their meat.  So the lions kill the buffalo, and the pups are spared.

The campaign ends when a Nile crocodile catches one of Blacktip’s pups and drags it into the Zambezi. It is the most graphic scene in the whole episode. I could not help but feel for the poor wild dog as it died in the crocodile’s jaws. This is a horrible way to die.

After that campaign, Blacktip retreats to her old territory, and Tait’s pack is able to return to its old haunts. Just before we hear that they have returned, Sir David Attenborough narrates that Tait died at the hands of lions. She was too old to keep running.  Her mate refused to leave her side, and he dies at the hands of the lions. Surely, this scene had to have been witnessed, but it was probably too horrific to be shown as part of this documentary.

The film ends with Tait’s family hooking with some errant males. Their booming cries are hauntingly beautiful as the new males join up.  A new mated pair is being crowned, and Tait’s daughter Tammy becomes the new lead female. And Tait’s dynasty continues on.

This film shows many amazing hunting scenes. I’ve never before seen any footage of African wild dogs hunting baboons, a pretty dangerous undertaking.  Baboons are smart and strong and have massive canine teeth. But the dogs are able to cause such chaos in a baboon troop that some young ones do get left unattended in the melee.

In another hunt, Tait’s pack runs an impala into the Zambezi, where the crocodiles instantly devour it.  You almost feel the dogs’ pain as that impala leaps into the water. That good meat, now lost to the archosaurs.

In another scene, we see Tait’s tiny litter of only two pups that are almost instantly threatened by honey badgers.  One of Tait’s daughters flies into action and begins harrying the ratels to drive them off.

This film was such wonderful high drama. It was like the story of Exodus from the Old Testament, complete with its own Moses figure who never makes to the Promised Land, that mixes in with the story of Ernest Thompson’s Seton’s story about Old Lobo, the marauding wolf of the New Mexico ranges that dies because he will not abandon his mate.

And this story is fully true and documented before the rolling cameras.

Every time I watched those dogs run on their hunts, I thought how much they reminded me of sighthounds.  Their svelte frames seemed to glide across the plains, running hard and fast after the game. Dan Belkin famously compared the saluki’s running style to this species, and in watching their endurance runs, I have to agree.

I particularly have enjoyed the way this series has made a conservation message part of the documentaries. In this one, the final part has Sir David Attenborough and the wild dog trackers standing and sitting among the packs. They tell us of the real problems facing these dogs. They need big territories to hunt their game, but most of the painted wolves don’t live in national parks. Livestock ranchers and pastoralists shoot and poison the dogs, even if they have legal protections. Zimbabwe has set up corridors for wildlife that allow travel between parks, but most African countries that have these dogs have not. So they must constantly run a gauntlet of often hostile humanity as they try to survive at the edge of lion and hyena territories.

The painted wolf, the painted dog, the African wild dog, or the Cape hunting dog are all names that we use for this animal. I prefer “painted wolf,” but I realize that no one knows what I’m talking about when I use that term. I hope that this film popularizes that name a bit more. The name “African wild dog” connotes something feral, something that we can just kill off and not consider more deeply.

Lycaon pictus, the painted wolf, has a far more noble connotation. No, they aren’t as magnificent as lions, but in their intense social behavior, we surely must see ourselves. Like us, they evolved in Africa as a distant running predators, and we probably were intense competitors for he same sorts of antelope.  Our kind wound up taking over the whole world. Theirs remained in Africa, and now our kind has come quite close to wiping them off the face of the earth.

Films like this episode of Dynasties fully reveal the plight of these amazing creatures. They are pack-hunting wolves evolved in parallel on the great continent of Africa, and we are only now realizing their marvelous ways.

 

 

 

 

 

 

 

 

 

 

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smithsonian wolf

The Smithsonian Magazine has an interesting article with the very simple title “Should the Himalayan Wolf  Be Classified as a New Species?”

The article details the work of scientists who have gone around Nepal collecting DNA samples from wolf scat.  This is a difficult project, for wolves in this region have experienced quite a bit of persecution from man. Further, where they live is quite inaccessible.

The researchers have found that these wolves have some uniqueness in their mitochondrial DNA, and they have also found that they share some genetic markers with the African golden wolf.

This is all interesting stuff, but I would caution going out on a limb and creating a new species called Canis himalayensis.

The big reason is the studies that have  attempted to figure out where these wolves fit have base part of their calculations on an assumption that gray wolves and coyotes last shared a common ancestor about a million years ago. We know that from full genome comparisons that this assumption is faulty, and the most divergence between gray wolves and coyotes happened about 50,000 years ago.  The DNA studies have shown that the Himalayan wolf is closer to Holarctic wolf, as is the African golden wolf, which means that Himalayan wolves aren’t as divergent from Holarctic gray wolves as coyotes are.

I have argued many times on this blog that the best way to think of coyotes in light of the evidence of this recent divergence between gray wolves is to think of coyotes as a form of gray wolf, and I think the name for coyotes should be Canis lupus latrans.  It makes at least as much sense as Canis lupus familiaris for pugs and Yorkshire terriers.

Because of the coyote’s position in light of full-genome comparisons, I think that we really shouldn’t think of the Himalayan wolf as a distinct species. I have no problem with Canis lupus himalayensis.

I am quite open to the African golden wolf being recognized as a subspecies of Canis lupus. In light of the work performed on Himalayan wolves and the recent discovery that African golden wolves are almost entirely gray wolf in ancestry, I think this might be correct.

And if you use this species model for gray wolves, you wind up with amazingly phenotypically and behaviorally diverse species, which is reflected in both wild and domestic forms.

I find this a lot easier to deal with than this model that has all these different species described that wind up exchanging genes all the time, and then, because we have declared one form endangered, we get into culling all the hybrids.

We need full genome comparisons between African golden wolves, coyotes, Holarctic gray wolves, and Himalayan wolves to suss out fully what these exact relationships are, but it seems that all of these animals are much more closely related to each other than we initially assumed. We also need more comparisons of ancient wolf DNA, including DNA from the remains of the ancestral Mosbach wolves (Canis mosbachensis).

So there might be a new species of wolf in the Himalayas, but I don’t think the evidence is all there yet. And there are lots of reasons to be skeptical.

But I do think that a unique high altitude subspecies of wolf does exist in the Himalayas. It is very likely that African golden wolves and Himalayan wolves are genetic relics of what was once a more genetically diverse Canis lupus. These lineages have since been lost in the main Holarctic wolf populations, just as we have lost the lineage that led directly to the domestic dog in these wolf populations.

After going through the red and Eastern wolf taxonomic mess, we should be careful in assigning new species status for unique wolf populations, particularly when we are using only very limited DNA assays.

 

 

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Clive out for a snowy stroll.

clive on a leash

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snuggly clive

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clive being playful

So when we had Clive out today he urinated a few times outdoors, including up against a tree trunk of one the silver maples in front of the house.

I made dinner this evening, and we had a boarding client who was coming to pick up her dog. Jenna took the client dog out for one last good walk about an hour after the sun set.

She came running back in the house telling me that she could smell red fox urine very strongly, and after careful examination, we noticed red fox tracks coming from across the road into our front lawn.

Clive is never taken near the road. He attracts too much unwanted attention, and our local conservation officer doesn’t like getting calls about a fox he knows is perfectly permitted and licensed.  Plus, Clive could get spooked and pull his leash loose, and he would probably run into the road and be hit by a car.

So what happened was that a dog fox in the neighborhood caught wind of Clive’s markings around the silver maples.  Last summer, I smelled where a red fox had urinated on one of these trees, as did every single one of our dogs, so I knew they were in the area. But now that we have a tame young male fox, the local breeding male fox is less than impressed with the young upstart leaving those markings on turf.

Clive is attracting the attention of the neighbors. My guess is we’re going to see lots more of their sign and maybe catch a glimpse of them as the late winter red fox mating season winds up.

I doubt that any of the local reds are cross foxes. All the ones I’ve seen in Ohio, West Virginia, and Pennsylvania have been the normal phase reds. But the foxes don’t know what color they are. They just operate by their nose and their base instincts.

Clive can never go wild. He’s from a long line of fur farmed foxes, and if he were to be released, he’s so friendly with people that he’d probably be suspected of being rabid and killed on sight.

So here is another aspect of owning a tame fox. The local red foxes don’t really care that much for the tame ones, and virtually everyone in the continental US lives near red foxes. If you bring a tame one into your home, you will be upsetting the locals, and I don’t just mean your human neighbors either.

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