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Posts Tagged ‘black-backed jackal’

dire wolf mesomelas

It was always assumed that the dire wolf and its kin, the endemic extinct North American wolves, were very closely related to modern wolves.

However, the genome of the dire wolf was just sequenced by a team of independent researchers at the Russian Institute of Cytology in Saint Petersburg.  The team of geneticists and paleontologists was led by Boris Yudin. The team wanted to have access to the remains of dire wolves at Rancho La Brea, but they were instead able to obtain access to several skeletons that were being held at the Indiana Museum of Natural History.

“It was very hard to get access to the specimens,” says Yudin,  who has always been fascinated by Pleistocene North American megafauna, “But once we did get access, the DNA sequences were quite easily obtained from the shoulder bones.”

“We were able to get one full genome sequenced, and then we began to compare this genome with other species in the genus Canis,”  says Yudin, “and using a Bayesian analysis, we were quite shocked to learn that the dire wolf wasn’t really a wolf at all.”

Most paleontologists had believed that the dire wolf was a sister species to the modern gray wolf, and if this assumption were true,  the dire wolf genome would be most similar to this species.

However, the dire wolf didn’t share an affinity with the gray wolf. Instead, it shared a much stronger relationship with the black-backed jackal, a species of canid found in East and Southern Africa, which is quite genetically distant from other wolves and jackals.

“There is even a debate as to whether the black-backed jackal even properly belongs in Canis,” says Yudin, “It is so genetically divergent.  But our research found that the dire wolf and the black-backed jackal are sister tax.”

Using the genetic differences between the dire wolf and the black-backed jackal to calculate when they last shared a common ancestor,  Yudin’s team estimated that the two species split only about a million years ago. Black-backed jackals and their current living closest relative, the side-striped jackal, are believed to have diverged from the rest of Canis some 5 million years ago, and the same is true of the dire wolf.

“The two divergent African jackals and the dire wolf form a clade, and if we are to classify the  two jackals outside of Canis, then the same will have to be done with the dire wolf,” Yudin points out.

“Within the dog family, the tendency towards parallel and convergent evolution cannot be underestimated.  We now know there are jackals and wolves that exist now and have existed that come out of divergent lineages. This is the most important discovery,” says Yudin.

So now we have the golden wolf of Africa, which is a convergent form of jackal out of the wolf lineage, and we have the extinct dire wolf, which was a divergent jackal that evolved into a wolf.

Yudin’s team plans on extracting the genome of the Armbruster’s wolf, which is conventionally believed to have been the direct ancestor of the dire wolf.  If this is true, then the Armbruster’s wolf will also share an affinity with the black-backed jackal.  The team also is beginning an analysis of Pleistocene coyote genomes from across the United States.

“It is an amazing time, ” says Yudin. “Many discoveries to be made.”

Disclaimer:  Please do not post this story as authoritative until reading this post that acts as a follow-up. 

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Trained black-backed jackal

I might sound weird, but if I ever go to Africa, this is the first species I want to see:

 

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hybrid

The scent of canid estrus wafts out of the clouds of the Harenna Forest in Ethiopia’s Bale National Park. It floats out of the wet jungle into the land of lichens that lies way up high in the Sanetti Plateau, where he smells it.

He stops to savor the scent, which is almost like that of his mother and sisters but not exactly.

Yet is strangely beguiling.

His kind are the red-coated “wolves” of the Ethiopian Highlands. They are Africa’s rarest canid and may be the rarest of all wild dogs. They spend their days hunting big-headed mole-rats and other rodents. They are rare and found only in these Afro-Alpine lands of Ethiopia.

His kind stay in the open moorland of lichens. They don’t wander down in the cloud forest. That is the realm of the black leopard, the creature that savors the taste of dog-flesh above all others and would love nothing more than to swipe an arrogant little tawny wolf.

But the smell is strong, and the last few months have been hectic in his pack. The bitches have all come in estrus, and his mother ran off his older sisters. By the law of Ethiopian wolves, only one bitch produces a litter and that one bitch is the sole mate of a single male.

Thus, our wolf friend has spent a long time smelling the beguiling fragrance of estrus but never getting a chance to partake in any mating.

This smell isn’t quite the same, but it’s so similar that he can’t help be drawn to it.

He abandons his caution and wanders down into the clouds. He soon finds himself in the wet jungle of the Harenna Forest. Moss lies hard upon the trees.Strange little monkeys chatter among the bamboo.

And the scent grows stronger.

He keeps following his canine  concupiscence through this strange world. For a creature so devoted to living in the open moorland, this jungle is a terrifying alien landscape. The buzzing of insect causes him to jump. The gentle falling rain upon the leaves vexes him.

Hunger soon begins set in, but just as he’s about to turn around and head home, he catches wind of some decaying meat.

He follows his nose and soon finds himself looking at the remains of a bushbuck. He also smells the odor of a cat of some sort, but it has long since passed. But smells another odor. It almost like that of his own kind but not quite.

He is in the land of strange wolves, and his hackles are raised.

He knows he might have to fight for a bit of food, but he doesn’t know who these strangers are.

He eats a bit of the meat and raises his head to scan the undergrowth. He must eat, yet he is terrified.

He hears the approach of canine steps. He bristles. The time for a fight is now!

Then the beguiling scent of estrus fills the air. The hackles go down. He doesn’t consciously realize that he’s becoming softened.

The sound of canine steps grows stronger. They stop. Then they grow stronger again.

Then out from behind a stand of kokisa trees comes the creature. Our wolf notices that this is source of the beguiling estrus odor, and though he was expecting a strange Ethiopian wolf from another pack, she not one.

But in some ways she is.

She is almost entirely gray with black hairs mixed in. Along the sides of her back the pelt mixes in such a way as to form two stripes, each running from her shoulder to her hip. Her tail is tipped in white.

She is a side-striped jackal.  Her kind is numerous. They are found throughout Africa south of the Sahara and the Sahel. They are creatures of the brush and thicket. Their kind almost never makes it onto nature documentaries.

They are that banal, that common, that no one would would waste time filming a den-site or extolling their virtues.

Our two creatures stare at each other over the bushbuck carrion. Neither knows what to make of the other. 3 or 4 million years of evolution separate the two species. One is a specialist of an ecosystem that is dying. The other is a generalist of tropical Africa.

But the genetic difference between the two is trivial at this moment.

The young jackal bitch has been driven from her parents’ territory.  She is too defiant of her mother over the kills they scavenge, and her mother just can’t handle such recalcitrance. Estrus made the situation worse, for in jackal society, only one bitch and one dog mate and have the pups. Her sister accepted her mother’s edicts that only she would mother pups, but our jackal bitch fought back and tried to mate with her brother and then her father.

One big fight ensued, and now our jackal bitch is running through the forests, alone and in estrus. She has no territory, and no other dog jackals from other families have courted her.

Her desire to mate is strong now.  And though she’s has been eating off this old leopard kill– one that the old leopard decided wasn’t worth hauling up into the trees– she hasn’t been herself at all.

On her old leopard kill stands a jackal of sorts. He’s bigger than any jackal she’s seen before. He smells different, but he also smells good.

Part of her says to approach. Part of her says to flee. The former is pushing her forward, and as the wolf’s face begins to soften, she feels at ease.

She approaches the red stranger. They touch noses. She backs off.  He wolf-grins. She pounces at him playfully. He backs off. They stare at each other again.

The ritual goes on for an hour. They begin to forget what they are. The strangeness of the moment becomes an odd sort of familiarly.

She licks his lips. He licks hers.  He stands proudly with his ears back. She playfully paws him.

They smell each other.

She spins around and puts her tail to the side. He mounts. There is a tie.

For three days the eat from the bushbuck carcass and mate in the jungle. She alerts him to the scent of the leopard and shows him how much fun it is to chase monkeys into the trees.

On the evening of the third day, the young wolf stoops to drink from a puddle. The black leopard springs from behind a bush and is on the wolf before he knows it. The leopard doesn’t know that he has killed a rare wild dog. He’s caught a big jackal, and jackal meat is so tasty that he has to take it up into the canopy for storage.

The jackal bitch goes looking for her mate. She barks and howls into the night. There is no answer.

An old male side-striped jackal who hasn’t had a mate for year finds her. She still smells of estrus, so she is accepted by him. The two jackals wander off into the darkness. They mate one time, but the two remain together as mates. Within her grow the whelps, one of which is sired by the old male jackal, and the other is the hybrid with the Ethiopian wolf suitor.

The pups are born in the den she digs. One pup is a typical side-striped jackal, while the other is marked with tan points and a black tail with no white tip. The hybrid grows up as a jackal, though she is clearly different.

One day, a group of researchers comes across her and takes her photograph. Then they take many photos.

She is so strange that the researchers believe she is new species of jackal. When her photos are posted online, a lot of debate develops about what she is. Is a new species?  Is she a hybrid of golden jackal (now a golden wolf) and side-striped jackal?  Is she a  hybrid of Ethiopian wolf and dog?  Ethiopian wolf and side-striped jackal?  Nah. She’s an unusual side-striped jackal without the stripes or the white-tail tip.

And the mystery jackal roams the Harenna Forest. The debate goes on.

This is the story of a hybrid.

***

The above is an entirely fictitious account of what might have happened to produce the unusual jackal in the photograph above. The current consensus— based upon looking at the many photos taken of the creature– is that she is an unusual side-striped jackal.

The truth is this debate really can’t be settled definitely. We have no DNA samples from the beast.

But the possibility of other hybrids beyond the usual subjects in the genus Canis has long fascinated me. It could happen. It just hasn’t been confirmed anywhere.

Although the likelihood of this hybridization occurring is pretty low, it is very likely that the two jackals endemic to Africa, the side-striped and black-backed jackals, can hybridize. The two species usually fight with each other, but there could be instances where they have crossed.

We just don’t have as many genetic studies on these jackals as we do with wolves, dogs, and coyotes.

But I bet there are some interesting stories in the genetic history of these canids.

They just have to be explored a bit more thoroughly.

Jackals are a mystery waiting to be solved.

 

 

 

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Part I:

Source.

Part II:

Source

A general rule in canids is that bigger canids kill and persecute smaller ones. In this case, black-backed jackals are killing off Cape foxes.

That would not be such a problem, because leopards keep jackal numbers in check.

This is a great example of the mesopredator release hypothesis, which holds that when larger predators are removed from an ecosystem, the smaller predators become more numerous and the species they normally kill suffer as a result of this imbalance.

Of course, the ranchers don’t want jackals either, but I guarantee you that they’d rather have jackals than the leopards.

When top level predators are taken out, all sorts of things happen to the lower trophic levels.

Increased predation by jackals on these two species of fox is just a consequence of removing leopards from the ecosystem.

 

 

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Ken Ham is known for using the dog family to defend the biblical concept of kind. After all, domestic dogs vary so much but can interbreed and produce fertile offspring, which they can also do with wolves (their wild ancestor), coyotes, and golden jackals.

So all these different animals must represent the dog kind, right?

Well, very early in the debate from last night , Ham went for the dogs again, comparing the different species and breeds of the genus Canis to Darwin’s finches. Darwin’s finches are more less divergent in morphology than all these dogs are, so they both must represent the respective dog and finch “kind.”

The problem is that all the weird morphology that exists in dogs is really nothing more than the selection pressures that have occurred since domestication. Domestic dog skull vary more than all the other species in the order Carnivora. That means that domestic dogs have skulls that diverge more than the differences between those of house cats and walruses. It is now thought that tandem repeats may play a role why dog heads have been able to become so diverse so rapidly through selective breeding, which is really nothing more than a really weird aspect of the dog genome.  Domestic dogs actually don’t vary that much from each other, and they also don’t vary greatly from wolves either, which is why they still have to be classified as Canis lupus familiaris.

Ken Ham bathers on how all these Canis were interfertile and thus the same kind, but here’s a challenge I guess he didn’t think about.

These two animals look very similar, and I’m sure that Ken Ham would say they are the same “kind.”

canis latrans

black backed jackal

If you didn’t know any better, you’d say that these two animals were the same speces, and if you were a creationist, you’d definitely say they were the same “kind.”

But if all living things on the earth now are all derived from an ancestral and clearly interfertile ancestral pair on the ark, then why can’t these two animals interbreed?

Yes.

The animal in the top photo is a North American coyote. It actually can interbreed with domestic dogs and wolves, and it has been bred to the golden jackal, which is actually far more closely related to the wolf and coyote lineage than the other jackals.

Indeed, there are two jackals that are found only in Africa that are not interfertile with the rest of the genus Canis. These two are the black-backed and side-striped jackals, which are even more divergent from the rest of the genus Canis than African wild dogs and dholes are.

The animal below is a black-backed jackal, and in Southern and East Africa it is ecologically quite similar to the Western and Latin American populations of coyote.

Because black-backed and side-striped jackals are genetically that distinct from the rest of the “dog kind,” then Noah surely would have had to have brought along a separate jackal kind.

But wouldn’t an all-knowing creator just ask Noah to bring the dog kind and populate Africa with an animal deriving from that ancestral dog kind? Having to put another pair of dog-like creatures on that already crowded boat seems like an awful waste. Kennel space was pretty limited.

Why go at it with such a divergent animal?

Most people don’t realize that these two endemic African jackals are so different from the rest of the genus Canis. Most have heard that golden jackals cross with dogs, and there is an assumption that all of these animals are very closely related.

They aren’t.

But if you were to play on this kind game a bit more, you’d think that these two animals would interbreed, and that there would be no way to breed a cute little dog like a beagle to a coyote. A black-backed jackal would be a much more logical mate, right?

beagle

 

But there have been several studies that have crossed laboratory strain beagles with coyotes (like this one: coyote beagle).

coyote beagle mated pair

 

The photo above is the male coyote protecting his beagle mate.

Here are their descendants:

beagle coydogs

Beagles and coyotes would clearly be part of the same kind, but coyotes and black-backed jackals would not.

But you’d never be able to guess that solely by looking at the animals.

And this is where the entire concept of “kinds” falls apart.

We have many different and often nasty debates about the taxonomy and classification of species, but we have these debates because we have some idea of what a species is.

The same cannot be used for the term “kind.”

A kind is really whatever one thinks it should be. It’s an ad hoc definition, one that is squishy and malleable, which means that it is perfect for people who like to misrepresent facts to twist around however they would like.

It’s precisely the sort of thing creationists like to use to bamboozle the science-illiterate public.

 

 

 

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Black-backed jackals are hunters as well as scavengers.  On Namibia’s Skeleton Coast, they hunt Cape fur seal pups:

Source.

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A side-striped jackal (Canis adustus), the jackal no one talks about.

We’ve always called the smaller wild dogs in the genus Canis jackals.

Historically, there were four species of jackal:  the golden (Canis aureus), the black-backed (Canis mesomelas), the side-striped (Canis adustus), and the Simien (Canis simensis).

Some authorities considered they coyote (Canis latrans) to be a jackal, usually called “the American jackal.”

At one time, they were all placed in the genus Thous.

This, of course, assumed that these animals were all closely related to each other.

However, as we’ve looked at DNA analysis, the relationship between jackals shows that the term “jackal” is actually quite meaningless.

In 1994, an mtDNA study revealed that the Simien jackal had certain mtDNA sequences that were more similar to wolves than other jackals. It was thought to be a relict population of primitive wolves that came into Africa during the Pleistocene.

And from that time forth, the English name of this species was change to “Ethiopian wolf.”  I don’t call it anything else.

However, as more work was performed on jackals, certain facts became evident.

Initial studies of black-backed, side-striped, and golden jackal mtDNA revealed that black-backs in East Africa had huge variances in their mtDNA. Golden jackals had mtDNA that was most similar to coyotes and wolves, while black backs and side-stripes were more similar to each other.

And then the phylogeny of the dog family was drawn from a high-quality sequencing of the dog genome revealed that golden jackals were much more closely related to coyotes and the wolf and domestic dog species than the Ethiopian wolf was. We still call them Ethiopian wolves, even though golden jackals are more closely related to actual wolves than those animals are.

The other issue revealed through this research was that Canis, as it is traditionally classified, is a paraphyletic genus. Modern taxonomy is generally concerned with classifying animals according clades. Clades are, by definition monophyletic. That is, they contain all the animals that descend from a particular lineage.

The dog genome research revealed that two species that are never traditionally classified as being part of Canis, the African wild (Lycaon pictus) and the dhole (Cuon alpinus), actually should be included there.  It turns out that black-backed and side-striped jackals are more distantly related to the rest of Canis than these two species are.

And if we classify Canis with all the jackals, the Ethiopian wolf, and  the wolf and dog species and leave out the dhole and African wild dog, we’ve created a paraphyletic genus that is not useful to modern taxonomy.

Some have suggested giving the two endemic African jackals their own genus.

And this would make Canis monophyletic without including the African wild dog and dhole.

However, the genus that would remain would include several species that are all chemically interfertile with each other (at least in theory). Species complexes exist throughout that part of the Canis, and delineating species is very difficult the species in this lineage.

Although Robert Wayne at UCLA has suggested that black-backed and side-striped jackals might be able to interbreed, no one has confirmed a hybrid between these two species. African wild dogs might be able to hybridize with dholes, but because they live on different continents and because they are both fairly endangered, no one has attempted to cross them. (There are persistent rumors that dholes can cross with domestic dogs. One dog breed, the Bangkaew dog from Thailand, is said to have derived from a dog/dhole cross. However, I don’t believe this claim has ever been tested through DNA analysis.)

All this research has revealed that how we have traditionally thought about the dog family is probably wrong.

The golden jackal is actually a primitive offshoot of the wolf lineage, just as the coyote in the New World is. The Ethiopian wolf is an even more primitive offshoot.

The two endemic African jackals are the two oldest living species in the Canis lineage. They are even more distinct from this lineage than dholes and African wild dogs are.

We do not have a good replacement word for jackal.

I’ve suggested that we call golden jackals “Old World coyotes” almost as a joke.

But I don’t have a good name for either of the two remaining jackal.

Because black-backed jackals are so scrappy, I’ve even suggested that we call them “wild Jack Russells.”

Whatever we call them, the term jackal, if it’s used to reflect close relationships between species, is utterly meaningless.

With the exception of the two found only Africa, it doesn’t refer to any animals that have a close relationship with each other.

It’s just a term we use for smaller wild dogs that are in some way related to wolves.

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