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Archive for the ‘wild dogs’ Category

kenya black-backed jackal

We think of interactions between predators as always antagonistic.  Meat is hard to come by, and if one comes by meat on the hoof, it is unlikely that the owner-operator of said flesh will give it up willingly.   Meat is a prized food source, and it is little wonder that most predators spend quite a bit of energy driving out competitors from hunting grounds.

Because of this antagonism, the domestication of wolves by ancient hunter-gatherers is difficult to explain. Indeed, the general way of getting wolves associated with people is see them as scavengers that gradually evolved to fear our species less.

This idea is pretty heavily promoted in the dog domestication literature, for it is difficult for experts to see how wolves could have been brought into the human fold any other way.

But there are still writers out there who posit a somewhat different course for dog domestication.  Their main contentions are that scavengers don’t typically endear themselves to those from which they are robbing, and further, the hunter-gatherers of the Pleistocene did not produce enough waste to maintain a scavenging population of wolves.

It is virtually impossible to recreate the conditions in which some wolves hooked up with people. With the exception of those living on the some the Queen Elizabeth Islands, every extant wolf population has been persecuted heavily by man. Wolves generally avoid people, and there has been a selection pressure through our centuries of heavy hunting for wolves to have extreme fear and reactivity. It is unlikely that the wolves that were first encountered on the Mammoth Steppe were shy and retiring creatures. They would have been like the unpersecuted wolves of Ellesmere, often approaching humans with bold curiosity.

As I have noted in an earlier post, those Ellesmere wolves are an important population that have important clues to how dog domestication might have happened, but the truth of the matter is that no analogous population of wolves or other wild canids exists in which cooperation with humans is a major part of the survival strategy. The wolves on Ellesmere are not fed by anyone, but they don’t rely upon people for anything.

But they are still curious about our species, and their behavior is so tantalizing. Yet it is missing that cooperative analogy that might help us understand more.

I’ve searched the literature for this analogy. I’ve come up short every time. The much-celebrated cooperation between American badgers and coyotes is still quite controversial, and most experts now don’t believe the two species cooperate.  Instead, they think the badger goes digging for ground squirrels, and the coyote stand outside the burrow entrance waiting for the prey to bolt out as the badger’s digging approaches its innermost hiding place in the den. The coyote gets the squirrel, and the badger wastes energy on its digging.

But there is a story that is hard to dispute. It has only been recorded once, but it is so tantalizing that I cannot ignore it.

Randall Eaton observed some rather unusual behavior between black-backed jackals and cheetahs in Nairobi National Park in 1966.

Both of these species do engage in cooperative hunting behavior. Black-backed jackals often work together to hunt gazelles and other small antelope, and they are well-known to work together to kill Cape fur seal pups on Namibia’s Skeleton Coast. Male cheetahs form coalitions that work together to defend territory and to hunt cooperatively.

However, the two species generally have a hostile relationship. Cheetahs do occasionally prey upon black-backed jackals, and black-backed jackals will often mob a cheetah after it has made a kill, in hopes of forcing the cat to abandon all that meat.

So these animals usually cannot stand each other, and their interactions are not roseate in the least. Eaton described the “normal interaction” as follows:

The normal interaction between these two predators occurs when the jackals hunt in the late afternoon and come into a group of cheetahs. The jackals, often four or five, are normally spread out over several hundred yards and maintain contact by barking as they move. When cheetahs are encountered by one of the jackals, it barks to the others and they all come to the cheetahs, sniffing the air as they approach apparently looking for a kill. If the cheetahs are not on a kill, the jackals search the immediate area looking for a carcass that might have just been left by the cheetahs. If nothing is found, they remain near the cheetahs for some time, following them as they move ; and when a kill is made the jackals feed on the leftover carcass. If the cheetahs have already fed and are inactive and if a carcass is not found nearby, the jackals move on.

However, Eaton discovered that one particular group of jackals and one female cheetah had developed a different strategy:

At the time I was there in November, 1966, one area of the park was often frequented by a female cheetah with four cubs and was also the territory of a pair of jackals with three pups. The jackal young remained at the den while the adults hunted either singly or together. Upon encountering the cheetah family, the jackals approached to about 20 yards and barked but were ignored except for an occasional chase by the cubs. The jackals ran back and forth barking between the cheetahs and a herd of Grant’s gazelles (Gazella granti) feeding nearby. The two jackals had gone on to hunt and were almost out of sight by the time the adult cheetah attacked two male Grant’s gazelles that had grazed away from the herd. The hunt was not successful. The jackals took notice of the chase and returned to look for a kill ; it appeared that they associated food with the presence of the cheetahs and perhaps with the chase.

One month later, while observing the same cheetah family, I noticed that the entire jackal family was hunting as a group. The cheetah and her cubs were about 300 yards from a herd of mixed species. This same herd had earlier spotted the cheetahs and given alarm calls. The adult cheetah was too far away for an attack,there was little or no stalking cover and the herd was aware of her presence. The cheetahs had been lying in the shade for about one-half an hour since the herd spotted them when the jackals arrived. Upon discovering the cheetahs lying under an Acacia tree, one of the adult jackals barked until the others were congregated around the cheetah family. The jackal that had found the cheetahs crawled to within ten feet of the adult cheetah which did not respond. The jackal then stood up and made a very pneumatic sound by forcing air out of the lungs in short staccato bursts. This same jackal turned towards the game herd, ran to it and, upon reaching it, ran back and forth barking. The individuals of the herd watched the jackal intently. The cheetah sat up and watched the herd as soon as it became preoccupied with the activity of the jackal. Then the cheetah quickly got up and ran at half-speed toward the herd, getting to within 100 yards before being seen by the herd. The prey animals then took flight while the cheetah pursued an impala at full speed.

Upon catching the impala and making the kill, the cheetah called to its cubs to come and eat. After the cheetahs had eaten their fill and moved away from the carcass, the waiting jackals then fed on the remains.

Eaton made several observations of this jackal family working with this female cheetah, and by his calculations, the cheetah was twice as successful when the jackals harassed the herds to aid her stalk.

Eaton made note of this behavior and speculated that this sort of cooperative hunting could have been what facilitated dog domestication:

If cheetah and jackal can learn to hunt mutually then it is to be expected that man’s presence for hundreds, of thousands of years in areas with scavenging canines would have led to cooperative hunting between the two. In fact, it is hard to believe otherwise. It is equally possible that it was man who scavenged the canid and thereby established a symbiosis. Perhaps this symbiosis facilitated the learning of effective social hunting by hominids. Selection may have favored just such an inter-specific cooperation.

Agriculture probably ended the importance of hunting as the binding force between man and dog and sponsored the more intensive artificial selection of breeds for various uses. It is possible that until this period men lived closely with canids that in fossil form are indistinguishable from wild stock (Zeuner, 1954).

Domestication may have occurred through both hunting symbiosis and agricultural life; however, a hunting relationship probably led to the first domestication. Fossil evidence may eventually reconstruct behavioral associations between early man and canids.

Wolves are much more social and much more skilled as cooperative hunters than black-backed jackals are. Humans have a complex language and a culture through which techniques and technology can be passed from generation to generation.

So it is possible that a hunting relationship between man and wolf in the Paleolithic could have been maintained over many generations.

The cheetah had no way of teaching her cubs to let the jackals aid their stalks, and one family of jackals is just not enough to create a population of cheetah assistants.

But humans and these unpersecuted Eurasian wolves of the Pleistocene certainly could create these conditions.

I imagine that the earliest wolf-assisted hunts went much like these jackal-cheetah hunts. Wolves are always testing prey to assess weakness. If a large deer species or wild horse is not weak, it will stand and confront the wolves, and in doing so, it would be exposing itself to a spear being thrown in its direction.

If you’ve ever tried a low-carbohydrate diet, you will know that your body will crave fat. Our brains require quite a bit of caloric intake from fat to keep us going, which is one of those very real costs of having such a large brain. Killing ungulates that stood to fight off wolves meant that would target healthy animals in the herds, and healthy animals have more fat for our big brains.

Thus, working together with wolves would give those humans an advantage, and the wolves would be able to get meat with less effort.

So maybe working together with these Ellesmere-like wolves that lived in Eurasia during the Paleolithic made us both more effective predators, and unlike with the cheetah and the black-backed jackals, human intelligence, language, and cultural transmission allowed this cooperation to go on over generations.

Eaton may have stumbled onto the secret of dog domestication. It takes more than the odd population of scavenging canids to lay the foundations for this unusual domestication. Human agency and foresight joined with the simple cooperative nature of the beasts to make it happen.

 

 

 

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red fox new jersey

New Jersey is a place I think of when I think of a place where animal rights ideology has become quite pernicious.  It is a densely-populated state that still has a lot of wild areas still left within its borders, but wildlife management decisions that include lethal control are quite controversial in that state.

For example, in my state of West Virginia, we have plenty of black bears. Black bears are state symbol, and if you go to any gift shop in the state, there will be black bears featured on so many different object. We love our bears, but we also manage them with hunting season.

New Jersey has the same species of bear, and this bear species is one of the few large carnivorans that is experiencing a population increase. Biologists know that hunting a few black bears every year doesn’t harm their populations at all, and in my state, bear tags go to promote bear conservation and to mitigate any issues between people and bears. Hunting these bears also gives the bears a healthy fear of humans, and it is virtually unknown for a bear to attack someone here. New Jersey has had a bear hunt for the past few years, but it has been met with far more controversy there than it ever would be here. Checking stations get protesters, as do wildlife management areas that are open to bear hunting.

Since the bear hunt began, human and bear conflicts have gone down dramatically. The population is thinned out a bit, and the bears learn that people aren’t to be approached.  But those potential conservation gains are likely to be erased sooner rather than later.

The animal rights people have become powerful enough in that state that no Democrat can make it through the primaries without pledging to end the bear hunt. The new Democratic governor wants to do away with the bear hunt.

But the bear hunt isn’t the only place where the animal rights people are forcing misguided policy.

A few days ago, I posted a piece about the inherent conflict between animal rights ideology and conservation, and it didn’t take me long to find an article about red foxes in Brigantine, New Jersey. Brigantine is an island off the New Jersey coast.

Like most places in the Mid-Atlantic, it has a healthy population of red foxes, but it also has a nesting shorebird population, which the foxes do endanger. One of the shorebirds that nests on the island is the piping plover, a species that is listed as “near threatened” by the IUCN.  Red knot also use the island on their migrations between South America and their Canadian arctic nesting ground. This species is also listed as near threatened, and both New Jersey and Delaware have enacted regulations and programs to protect them.

At Brigantine, people began to discover dead red foxes in the sand dunes, and because red foxes are canids and canids are charismatic. It was speculated that the foxes were poisoned, and the state DEP was asked if the agency had been poisoning foxes there.

The state apparently answered that it had no been poisoning foxes on Brigantine’s beaches. It has been trapping and shooting red foxes.

To me, the state’s management policy makes perfect sense. North American red foxes are in no way endangered or threatened. Their numbers and range have only increased since European settlement, and they are classic mesopredators.  Mesopredators are those species of predator whose numbers would normally be checked by larger ones, but when those larger ones are removed, the smaller predators have population increases. These increased numbers of smaller predators wind up harming their own prey populations.

This phenomenon is called “mesopredator release.” It is an important hypothesis that is only now starting to gain traction in wildlife management science. What it essentially means is that without larger predators to check the population of the smaller ones, it is important to have some level of controls on these mesopredators to protect biodiversity.

Animal rights ideology refuses to consider these issues. In fact, the article I found about these Brigantine foxes is entitled “These adorable foxes are being shot to death by the state.”   The article title is clickbaitish, because the journalist interviewed a spokesperson at the DEP, who clearly explained why the fox controls were implemented.

The trappers who took the foxes probably should have come up with a better way of disposing of the bodies. One should also keep in mind that New Jersey is one of the few states that has totally banned foot-hold traps for private use, so any kind of trapping is going to be controversial in that state. So the state trappers should have been much more careful.

But I doubt that this will be the end of the story. The foxes have been named “unofficial mascots” of Brigantine, and it won’t be long before politicians hear about the complaints. The fox trapping program will probably be be pared back or abandoned altogether.

And the piping plover and red knot will not find Brigantine such a nice place to be.

And so the fox lovers force their ideology onto wildlife managers, and the protection of these near threatened species becomes so much harder.

This sign was posted in 2016 after the first dead foxes were found:

save our foxes

But I don’t think many people will be posting “Save Our Piping Plovers.” Most people don’t know what a piping plover is, but red foxes are well-known.

They get their special status because they are closely related to dogs, and people find it easy to transfer feelings about their own dogs onto these animals.

This makes sense from a human perspective, but it makes very little sense in terms of ecological understanding.

And it makes little sense for the foxes, which often die by car strikes and sarcoptic mange, especially when their population densities become too high.

Death by a trapper’s gun is far more humane than mange. The traps used are mostly off-set jawed ones, ones that cannot cut the fox as it is held. The trap is little more than a handcuff that grabs it by the foot and holds it. The traps are checked at least once a day, and the fox dies with a simple shot to the head, which kills it instantly.

And the fox numbers are reduced, and the island can hold rare shorebirds better than it could before.

In trying to make a better world for wildlife, we sometimes have to kill. This is an unpleasant truth.

And this truth becomes more unpleasant when we start conflating animal rights issues with conservation issues. Yes, we should make sure that animals are treated humanely, but we cannot make the world safe for wildlife without controlling mesopredators and invasive species.

I think that most of the fox lovers do care about wildlife, but they are so removed from wildlife issues on a grand scale that it becomes harder to understand why lethal methods sometimes must be used.

My guess is these people like seeing foxes when they are at the beach and don’t really think about these issues any more than that.

It is not just the wildlife exploiters and polluters that conservationists have to worry about. The animal lovers who extend too much animal rights ideology into conservation issues are a major problem as well.

And sadly, they are often the people that are the hardest to convince that something must be changed.

I don’t have a good answer for this problem, but it is one that conservationists must consider carefully as the future turns more and more in the favor of animal rights ideology.

 

 

 

 

 

 

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golden wolf vs. black backed jackal

Not the best photo, but this is golden wolf on the left and a black-backed jackal on the right. I screen-captured this image from this documentary, which was made before the big golden jackal revision that happened a few years ago.

There is still a big debate on how classify the creature formerly known as the African golden jackal. It is clearly closer to gray wolves and coyote than to the Eurasian golden jackal, but the exact closeness requires further research.

The black-backed jackal on the right is a much older species. It has been known from the fossil record in Africa for over two million years, and the wolf-coyote-golden wolf lineage last shared a common ancestor with it around 4.5 million years ago.

Depending upon when we finally determine when the golden wolf diverged from the modern gray wolf, it may have evolved from larger ancient gray wolves that adapted to fit the generalist jackal-like niche, or it may have evolved from a African population of Canis mosbachensis.

The black-backed jackal is derived from the earliest wolf-like canids to have entered the Old World from North America. Those early wolves were all smaller and jackal-like, and its appearance and adaptations are of the primitive type.

So here we have two species that look like they might just be color phases of the same species but actually are divided by millions of years of evolution. One is a truly primitive member of its lineage. So primitive and basal that its now classified in a different genus (Lupullela). The other came from a more derived source that evolved parallel characteristics with the primitive one.

Parallel evolution is a hell of a thing, especially when it comes to canids. So much of this parallel evolution has been missed in paleontology and in the conventional methods of taxonomy that use only morphology. Not recognizing the parallel evolution issues is why we didn’t notice that coyotes and gray wolves were much more closely related than we ever could have imagined. It’s also why we thought bush dog belonged with the dhole and African wild dog, just because their teeth are so similar, and it is also why an affinity has been suggested between crab-eating foxes and raccoon dogs, even though they are in entirely different lineages. It is also why there was a suggestion that red wolves represent an ancient lineage of North American wolves, when they are now probably hybrids between coyotes and gray wolves.

Parallel evolution messes up a lot of things. Our eyes and our measuring instruments can fail us.

But the correction of these failures reveals a much more mysterious world.

That’s the inherent beauty of science. Each correction is a revelation.

 

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spotted urocyon

This gray fox has some white marking on its face and feet.

We can speculate about where they came from. Domestication process maybe?

We know, though, that these white marking didn’t come from crossbreeding with domestic dogs, because the gray fox lineage diverged from the rest of the dog family 10-12 million years ago.

Whatever the reasons for its white markings, it is a stunning animal nonetheless.

 

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African golden wolf

What we do know about the origins of Canis species is much more hotly-contested than what we know about the evolution of our own species. The earliest fossils of the genus are roughly 6 million years old, and the oldest species in the “wolf lineage” is Canis lepophagus, which lived in the American Southwest and Northern Mexico 5 million years ago.  This species is often posited as the direct ancestor of the coyote, and it may have been a direct ancestor of all the entire wolf-like canid lineage.

Of course, recent discoveries that have come from full genome comparisons make things a little complicated. With the discovery that coyotes diverged from gray wolves as recently as 50,000 years ago, the linear evolution from Canis lepophagus to Canis latrans is probably invalid.  Further another full genome study that used a single Israeli golden jackal (Canis aureus) as the outgrouping sample to determine when dogs and gray wolves split, revealed that this particular jackal diverged from gray wolves less than 400,000 years ago.

Both of these dates are far more recent that the millions of years that are assumed to separate these wolf-like canids from each other. Of course, more work must be done. We need more studies on coyote genomes, but these researchers have come across what could be the most important discovery in our understanding of the evolution of Canis species. Depending upon the study, coyotes and gray wolves were thought to have diverged between 700,000 to 1 million years ago, and this assumption is used to calculate when other Canis have diverged.

Now, this assumption always did bother me, because if Canis lepophagus leads directly to Canis latrans, where do wolves fit in?  Because in order for that model to work, gray wolves have to evolve from a very small coyote-like ancestor with very few transitions in between. It always just seemed to me like it was unworkable.

Further, there is a whole host of literature on the evolution of gray wolves in Eurasia, and in most European literature, there is a general acceptance of how gray wolves evolved from a smaller wolf called Canis mosbachensis.

Wolfgang Soergel, a German paleontologist at the University of Tübingen, discovered Canis mosbachensis at a site near Jockgrim in 1925. The animal is sometimes called the “Mosbach wolf,” which means it was found in the Mosbach Sands, where many fossils from the Middle Pleistocene have been found.

Mark Derr was particularly interested in this species in his How the Dog Became the Dog.  He points out that the earliest dated fossils of this species are 1.5 million years old and come from the ‘Ubeidiya excavations in Israel.  The most recent Canis mosbachensis remains in Europe are about 400,000 years old, after which time they were replaced by Canis lupus.  Derr speculated about the relationship mosbachensis might have had with early hominin species, which were also well-known from that site, and suggested that they might had some kind of relationship.

Further, there is a growing tendency among paleontologists to group Canis mosbachensis with another wolf that was its contemporary. This wolf, called Canis variabilis, was discovered at the Zhoukoudian Cave System in China in 1934. Its discoverer was Pei Wenzhong, who became respected paleontologist, archaeologist, and anthropologist in the People’s Republic of China. It was a small wolf with a proportionally smaller brain, and it has long been a subject of great speculation.

And this speculation tends to get lots of attention, for this cave system is much more famous for the discovery of a type of Homo erectus called “Peking Man.”  It is particularly popular among the people who insist that dogs are not wolves, which is about as scientifically untenable as the “birds are not dinosaurs” (BAND) clique of scholarship.

Mark Derr and as well as more established scholarship have begun to group variabilis and mosbachensis together. Variablis has also been found in Yakutia, and it may have been that varibablis nothing more than an East Asian variant of mosbachensis.

These wolves were not large animals. They varied from the size of an Eastern coyote to the size of an Indian wolf. They were not the top dogs of the Eurasian predator guild.

Indeed, they played second fiddle to a larger pack-hunting canid called Xenocyon lycaonoides, a large species that is sometimes considered ancestral to the African wild dog and the dhole, but the recent discovery of Lycaon sekoweiwhich was a much more likely ancestor of the African wild dog, suggests that it was more likely a sister species to that lineage.

Although canids resembling Canis lupus have been found in Alaska and Siberia that date to 800,000 years ago, anatomically modern wolves are not confirmed in the Eurasian faunal guild until 300,000-500,000 years before present.

I’m throwing a lot of dates at you right now, because if the modern Canis lupus species is as recent as the current scholarship suggests, then we can sort of begin to piece together how the entire genus evolved.

And we’re helped by the fact that we have an ancient DNA study on a Yakutian “Canis variablis” specimen. This specimen would have been among the latest of its species, for it has been dated to 360,000 years before present. Parts of its ancient mitochondrial DNA has been compared to other sequences from ancient wolves, and it has indeed confirmed that this animal is related to the lineage that leads to wolves and domestic dogs.  The paper detailing its findings suggests that there is a direct linkage between this specimen and modern dog lineages, but one must be careful in interpreting too much from limited mitochondrial DNA studies.

360,000 years ago is not that far from the proposed divergence between gray wolves and the Israel golden jackal in genome comparison study I mentioned at the beginning of the post.

This really could suggest something a bit controversial and bold. It make take some time for all this to be tested, but it is a hypothesis worth considering.

I suggest that all this evidence shows that Canis mosbachensis is the ancestor of all interfertile Canis, with the possible exception of the Ethiopian wolf.

If the Ethiopian wolf is not descended from that species, then it is a sister taxon. It is not really clear how divergent Ethiopian wolves are from the rest of interfertile Canis, but their divergence estimates currently suggest that it diverged from the rest of the wolf-like clade 1.6 million years ago, which is just before Canis mosbachensis appears in the fossil record.

If that more recent date holds for the split for the Eurasian golden jackal, then it is almost certain that this hypothesis is correct.  The Eurasian golden jackal may be nothing more than a sister species to a great species complex that includes the coyote, gray wolf, dingo, and domestic dog that both derived from divergent populations of Canis mosbachensis. 

The exact position of the Himalayan wolf and the African golden wolf are still not clear. We do know, though, that both are more closely related to the coyote and gray wolf than the Eurasian golden jackal is, and if its split from the gray wolf is a recent as less than 400,000 years ago, then it is very likely that all of these animals are more closely related to the main Holarctic population of gray wolves than we have assumed.

The recent divergence of all these Canis species is why there is so much interfertility among them.

And if these animals are as recently divergent as is inferred, their exact species status is going to be questioned.

And really should be, at least from a simple cladistics perspective.

More work does need to be done, but I don’t think my hypothesis is too radical.

It just seems that this is a possibility that could explored.

 

 

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The rarity of canid hybrids

black coyote

The black allele that exists in wolves and coyotes originated in domestic dogs and entered those species because of hybridization.

Ever since Meet the Coywolf appeared on Nature on PBS and then made a long run on Netflix, the concept of hybridization within closely related Canis species has captured the public imagination.

But what is interesting about hybrids in Canidae is they have only been documented within these Canis species, which are domestic dogs/ dingoes/gray wolves, Ethiopian wolves, coyotes, Eurasian golden jackals, and African golden wolves, and between swift and kit foxes where their ranges overlap.  Sterile hybrids have been produced by crossing red foxes (usually silver phase) with arctic foxes (usually blue phase) in fur farms.

And as it stands right now, these are the only hybrids that have been documented.

This rarity is quite unusual, because the cat family has lots of hybridization by comparison.  Intergeneric hybrids have been produced by crossing cougars with leopards, which are called “pumapards,” and hybrids have even been produced crossing ocelots and bobcats. Domestic cats have been hybridized with servals and leopard cats. Pantherine hybrids are famous, including the very real liger and leopon.

But no one has produced a true intergeneric hybrid in Canidae. There are rumors of a dhole-Eurasian golden jackal hybrid from British India, but the account of this animal is literally one sentence in a book by Reginald Pocock. The Thai Bangkaew dog was said to be a dhole hybrid, but the current thinking is that the wild dog in its background is the Eurasian golden jackal.  Rumors of a dog crossed with a crab-eating fox were passed around a few years ago, but I don’t remember anyone checking out this supposed hybrid.

No one has ever produced a real vulpine fox-dog hybrid. No one.  I’ve run into several accounts of a creature called a “dox,” but they all existed before the discovery of DNA.

But no one has seen a dox since then.

It is really interesting that hybridization is far less common in Canidae than Felidae, and it certainly worth exploring why.

Losing chemical interfertility clearly does not happen at the same rate, and the mechanisms by which this happens are not clearly understood.

 

 

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bat-eared fox vs cheetah

As I noted in an earlier post, I am skeptical that the extinct North American “cheetahs” are the root cause of the pronghorn’s speed.  I am not alone in this skepticism, but my skepticism is rooted in the evasion strategy that pronghorns use. They flat-out run, whereas the antelope that are part of the true cheetah’s prey sources often use complex twisting and turning behavior to evade the swift cat. The pronghorn is a super long-distance runner, and its evasion strategy is more in keeping with a creature that was hunted by long-running dogs or perhaps the only hyena that ever existed on this continent.

I’ve been thinking a lot about cheetahs lately. A few weeks ago, I was watching an episode of Nature on PBS in which the filmmakers were putting cameras on various animals. They put some cameras on some young cheetahs, and I was somewhat surprised at a species they seemed to like to target.  They were constantly harrying and harassing bat-eared foxes.

It was at that moment that two ideas I had in my head were connected.  I’d been toying around with writing something on this space about the Afrikaans name for the bat-eared fox, which is “draaijakkals.” The name means “turning jackal,” and the animal got this name because when a dog would get after one, it would start twisting and turning as it ran.  Now, this certainly would be the fox for sighthound enthusiasts to course.

But it really doesn’t need this skill to hunt its prey. In South Africa, it was believed they were a threat to lambs, but the truth is that 80-90 percent of their diet consists of one species of harvester termite, which don’t require much chasing.

Their running behavior is an evasion strategy, not a hunting strategy.

Why does this fox have such a gazelle-like evasion strategy? Well, I will engage in a bit of speculative zoology here:

The cheetah did it.

Cheetahs do not regularly target bat-eared foxes, but when they do, they are successful pretty often. Gus and Margaret Mills, who studied cheetahs in Kalahari, reported that cheetahs rarely hunt bat-eared foxes, but when they did, they managed to catch and kill their quarry 44.4 percent of the time. One emaciated cheetah queen, though, came to target bat-eared foxes as a major part of her diet.

Cheetahs are not migratory species, but many of their prey sources are.  And during times in which ungulates can’t be hunted, some of them could very well come to rely upon bat-eared foxes as their favored prey.

Although bat-eared foxes do derive from a basal lineage of vulpine foxes, the exact species first appeared in the fossil record 800,000 years ago.  And they evolvedin areas where cheetahs were present.

This little hypothesis has some problems. One of them is that cheetahs don’t often target bat-eared foxes, but we do know cheetahs will when they are unable to hunt ungulates.

But does cheetah predation on bat-eared foxes happen enough to have had that effect upon the canid’s evasion strategy?

I don’t know if we can answer that question, but it seems to me that the bat-eared foxes’ odd twisting and turning and doubling back behavior comes from cheetah predation as a selection pressure.

It is worth considering. Maybe I am way off, but I don’t know of any other canid that runs from predators in this fashion.

Or maybe it’s just another Just-So Story.

 

 

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