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Archive for the ‘Unusual animals’ Category

A slow one

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This "strawberry" leopard appears to be unable to produce black pigment. Its nose and lips, as well as the skin around its eyes, appear to be reddish brown.

From io9.com:

You’re looking at the only known example of what conservationists are calling a strawberry colored African leopard. The big, pink-hued cat — which makes its home at South Africa’s Madikwe Game Reserve — is affected by erythrism, a poorly understood genetic condition that causes him to either overproduce red pigments or underproduce dark pigments in his coat.

“It’s really rare,” explained Luke Hunter, president of the wild cat-conservation group Panthera, whom Madikwe officials consulted with about the cat’s unusual coloration. “I don’t know of another credible example in leopards.”

According to National Geographic, erythrism is unusual in [wild] carnivores, which makes sense if you think about it — pinkish fur, after all, is probably not the most ideal form of camouflage for animals whose predatory techniques rely on stealth. But this particular leopard appears to be doing fine. “He’s obviously a successful animal,” said Hunter.

This is the first one that has been seen in recent times. However, Messybeast.com, a great resource for information about just about anything relating to unusual animals, has several images of taxidermies of what appear to be red leopards with a similar mutation, though much darker red in color. (There are some really interesting morphs on that page. The “cobweb panther” looks like a melanstic leopard with ich!)

There is some suggestion that these dark red leopards are faded black leopards, which is a possibility.  Spots can still be seen on black leopards, so exact chemical make up of the fur on the spots is different from the fur that comprises the background.

So it is possible that these red leopards are faded black ones. The fading could have happened due to age or the treatments used to preserve the skin.

I am not sure if anyone has examined these mahogany red leopards to see what they exactly are or were.  DNA could be extracted from at least some of these taxidermies. And then we could find out if they were black leopards or not.

This strawberry or red coloration is likely a recessive trait, and this should be of concern to leopard conservationists.

Several years ago, a brown and white giant panda was discovered in the Qinling Mountains.

It is generally pretty uncommon for very rare recessive traits to be expressed in the wild.

It’s just the nature of recessive traits. They can only be expressed when they are homozygous, and in nature, there is usually enough mixing of genes to keep recessives  diluted in a population.

When the brown panda was discovered, there became lots and lots of worries about inbreeding the Qinling Mountain pandads, which are the more stressed and fragmented of the two populations of giant pandas. Habitat fragmentation may mean that these pandas are becoming inbred, and a sign of that inbreeding is the sudden appearance of unusual recessive traits that are normally hidden.

We don’t typically think of common leopards as being endangered at all.

They are currently the most widespread of the big cats, and range from South Africa all the way to the Russian Far East. They are currently extirpated from much of North Africa and the Middle East, and there is an unusual isolated population of leopards on Java, which are somewhat smaller than normal common leopards.

However, genes do not flow across Asia and Africa as they once did.

As I noted earlier, leopards no longer exist in most of the Middle East and North Africa. Only isolated populations still exist.

And even within the core of leopard range in Asia and Sub-Saharan Africa, the habitat is greatly fragmented.

Leopards and lions no longer cast genes across vast areas. Very often, they are left in smaller preserves, where it is very easy for genetic bottlenecks to form. Dominant males, which rule prides in lions and overlapping territories of females in leopards, are not overthrown on a regular basis, making it more and more likely for a male to wind up mating with his daughters. New blood in the form of enterprising young males no longer enters the gene pool.

Madikwe is actually trying to solve some of these problems. There is a current move to create a corridor between it and Pilanesberg National Park.

This corridor would allow more of a gene flow to exist between populations of lions and leopards, and it would be a great asset to genetic sustainability of wildlife in this region.

This is more and more of a problem than one might expect.  Leopards are considered “near threatened” by IUCN, and lions are considered “vulnerable,” a much more serious distinction.  If lions and leopards cannot exchange genes over a larger area, the better for both species. Neither has experienced much inbreeding in their natural history, and thus, they have no had an opportunity to experience much purging or evolve any inbreeding tolerance.

Unusually colored wild animals often attract attention, but they can be indicative of more serious problems.

This cat seems to be doing fine.

Let’s just hope the population in which he lives will continue to thrive.

***

I should note that there are situations in which recessives can exist at much higher levels than one might normally expect.

One of these traits has a certain selective advantage, it will appear much more frequently than normal recessives.

Among these is melanism in leopards.

Melanistic leopards are most common in jungle or rainforest environments — particularly in Southeast Asia– where it may confer an advantage. A black cat can easily hide the shadows of the night, and because leopards are the consummate ambush predators, this might explain why there are so many black leopards– even though this is a recessive trait.

There is some suggestion now in the literature that melanism may also enhance the immune system.

But if recessives do not confer any advantage, they normally aren’t very common at all.

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Source.

This might be the funniest thing ever!

The full video!

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In the woods surrounding my house, a melanistic white-tailed deer has been spotted running with its normal-colored mother.

It’s one of this year’s fawns.

If I can get a photo of it, it will be posted.

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Aaron Hall

Aaron Hall, "Lion Hunter of the Juniata" and founder of the legendary strain of Pennsylvania panther dogs.

I came across an account of an unusual breed of hunting dog that was developed in Centre County, Pennsylvania. This account comes from Extinct Animals of Pennsylvania by Henry Wharton Shoemaker. The text was originally  published in 1907, but the actual account comes from period between 1845 and 1869 in which a legendary cougar hunter named Aaron Hall was said to have killed fifty “panthers.”

Hall’s legendary status had left him with the sobriquet “Lion Hunter of the Juniata.” He had styled himself as the central Pennsylvania version of Davy Crockett.

And like any great hunter of those days, he had a pack of hunting dogs that helped him pursue his quarry.

Unlike any other hunter of that day, though, he had bred a rather unusual strain of cougar hound.

His massive dogs were run in pairs that then pursued the cougar until they could catch it by the ears– one dog on each ear, very similar to how hog catch dogs are used. It is also very similar to the way that the borzoi caught wolves.  The borzoi would grab the wolf by the sides of the neck, usually two dogs on either side.

The dogs were said to be the result of breeding old-type bulldogs, mastiffs, Newfoundlands, and bloodhounds together to produce a superior cougar hound. They dogs were said to have been so large that a former Pennsylvania game commissioner was able to ride one of them.

I have some issues with the veracity of these claims, but it is known that the mastiff-type dogs can be used to hunt large cats. Fila Brasileiros were used to hunt jaguars and South American cougars, and the Dogos Argentinos were also used to hunt cougars in their native country. Newfoundland dogs were very common in America at the time and were considered an appropriate dog to use for hunting various species of game, although waterfowling was their most common purpose. Bulldogs were probably chosen for their tenacity and ability to grip recalcitrant and powerful quarry, and bloodhounds have legendary noses. The mixture makes sense.

However, the story about the dogs grabbing the cats by the ears is a bit too far fetched for me to accept. A cougar is a very strong and agile animal. If cornered by dogs, it is going to fight very hard. Because its ears aren’t that large, my guess is that the dogs would have a very hard time holding the cats by the ears. They would simply be clawed to pieces, even if they did manage to get them by the ears.

Keep in mind that a cougar can kill a lone wolf, and it wouldn’t have very much trouble killing a domestic dog of any size. (There is a very good account of a cougar killing at captive wolf in Jim and Jamie Dutcher’s Wolves at Our Door.) Most modern cougar hounds tree the cats or hold them at bay. Very few of them engage in mortal combat with the cats. I seriously doubt that any dog would be able to fight a cougar until it was able to grab it by the ears.

Unless Hall or Sober were very small men, I seriously doubt that he could ride any dogs resulting from his crossbreeding. The biggest mastiffs have exceeded two hundred pounds, but if you’re crossing in smaller bulldogs, bloodhounds, and the slightly smaller Newfoundland of the day, it is very unlikely that anyone would be able to produce animals of that size.

Shoemaker wrote a lot about the folk culture of rural Pennsylvania, and theis story sounds a lot like mountain person’s tall tale. Mountain culture in Pennsylvania isn’t that different from mountain culture here, and I can tell you that telling stories like this one are almost de rigueur, especially when someone starts talking about his hunting dogs. Maybe Shoemaker was playing around with this lore, or maybe someone was playing a trick on him. After all, he was an outsider, a graduate of Columbia and a native New Yorker who had grown up in India. Such outsiders are very often told tall stories, for nothing can make a rural person with limited educational and economic opportunities feel better than when he or she gets some outsider to believe some outlandish story.

He does mention that many people of this region were keeping cougar dogs, but most of the dogs used to hunt cougars were “fices” or “whippets.”

One of the great ironies about cougars is that they were known for having a great deal of fear of dogs. Although they were capable of killing a dog easily, they normally would run if pursued by a pack of them.

Normally, these pursuits end with the cougar a tree and dogs barking at them. My guess is that if a cougar had found itself being chased by Hall’s cougar dogs, it would have run for the nearest tree before the dogs could even get close to it. This would have meant that it would have been next to impossible for the dogs to grab them by the ears. (Unless those horse-sized curs could also climb trees.)

I particularly like the story about the Pennsylvania panther dogs, but I am very skeptical that this story is real. Maybe Hall really did have big cougar hounds, but they didn’t hunt in exactly in the way described. Maybe they held the cats at a bay or pushed them into the trees. Some of them were probably much larger than the typical hunting dog of the region, and thus, they were given such an outlandish size.

Hall’s strain of panther dog went extinct shortly after his death in 1892. We can never really know for sure, but I think the chances of these dogs hunting in the way described are not very good.  I can’t imagine that a cougar would allow itself to be held by the ears in such a fashion.

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warrah

warrah or Falkland Islands wolf

Remember my post on the enigma of the warrah or Falkland Islands wolf?

I stated that we didn’t have the foggiest clue what its ancestry was, although early studies of its DNA suggested that it was derived from something like a coyote.

It has been speculated that the culpeo and the other zorros or wolf-like foxes of South America are its closest relatives.

Well, a new study was released yesterday that suggests that the warrah’s closest relative was the maned wolf. The lineage of the two species split 6 million years ago, when the ancestors of both species lived in North America.

Yes, South America might have a great diversity of wild dog species today, but all of its wild dogs descend from North American ancestors. Canids moved to South America 2.5 million years ago.

So the enigma of the warrah has been solved.

However, no one has found any North American canids that could be considered the ancestors of the warrah or maned wolf.

***

I need to say here that the maned wolf is one of the more bizarre wild dogs. In fact, I can’t think of a stranger animal for the warrah to count as its closest relative. Remember, the warrah looked like a dingo, a culpeo, or a coyote. Its appearance wasn’t that strange. It was the fact that it was located on isolated island that made people wonder about it. If it had been found on the mainland, it would have been instantly grouped with the South American zorros.

They stand over three feet at the shoulder but weigh only about 44-55 pounds. Their long legs are an adaptation to living in their grassland habitat, where the grass often grows too tall for a shorter-legged dog to see its prey.

Unlike other large wild dogs, the maned wolf does not form packs.  A monogamous pair shares a territory, but they normally are not seen together in that territory. They apparently come together only to mate.

Also unusual for a wild dog of this size, over 50% of its diet is vegetable matter. One particular species of fruit, the “wolf apple (Solanum lycocarpum) is named because  maned wolves like to eat it. In captivity, these animals have been fed like normal canids and then have developed bladder stones. Their bodies simply cannot metabolize such high protein diets.

Even more strangely, their urine smells like marijuana. Their urine contains a pyrazine, which also occurs in marijuana. It is possible that their urine gets this distinctive odor from the pyrazine.

The warrah’s only living relative is much stranger than it was!

***

Speaking of South American wolves.

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European eel

One of the most interesting theories postulated by The Centre for Fortean Zoology is the hypothesis that many lake monster sightings are overgrown eels. Now, this theory was lampooned on Penn & Teller’s Bullshit, and in the youtube upload of the Centre’s documentary Eel or No Eel, the comments are mostly negative. How could there be a giant eel any European lake?

The theory goes that some eels are sterile (“eunuch eels), and unlike other eels, they don’t leave lakes and rivers to spawn in the Sargasso Sea. They simply stay in fresh water, eat, and get big.

We do have some evidence of what happens to European eels that don’t go through their normal life cycle.

In 1859, an eel was confined to a well in Sweden. It remained trapped in the well until it was recaptured in 2008. It was over 149 years old, and yet, it had survived in fresh water all this time. It was 53.5 centimeters  (21.1 inches) long, and its eyes were unusually large.

Now, a 21 inch eel is hardly a giant animal. However, it is possible that an eel living in a more nutrient-filled environment than a well, could grow large during such a prolonged life.

However, I don’t think that the supposed large eels are eels that simply remained trapped in freshwater due to confinement or sterility. I think there is something else at work here.

One aspect of natural selection that is often left out is the human element. Now, we often hear about the peppered mouths of Britain, which come in two basic color morphs. One is lighter and perfectly camouflaged against a tree with lichens and moss on it, while the other is darker and better camouflaged against soot covered tree. With the Industrial Revolution, the darker moths proved to be better camouflaged against bird predation, and thus, the majority of the population became dark-colored. (This trend has since reversed as Britain has tried to clean up emissions from power plant and factories.)

Now, that is a textbook example of how human effect natural selection. I have also postulated that the ancient wolf population from when modern wolves and domestic dogs descend was originally much more dog-like. The wolves were curious about people and were easily tamed. When we began to domesticate other livestock, dogs and wolves began to fully split, as man selected dogs that were unlikey to prey on livestock and man began killing wolves on a large scale. This selection pressure on wolves ratcheted up as the Industrial Revolution made poisons, traps, and fire arms more readily accessible. We have selected dogs to be extremely tame and docile. They don’t fear new things as much as wolves do, and dogs have also evolved innate human reading abilities and associative learning abilities that make them rather interesting animals. Our pesecution of wolves has selected for more reactive, nervous, and fearful animals– animals that are nearly impossible to tame, even if bottle-reared. That’s why I think there is such a heightened difference between the two animals, even though every genetic study suggests that they are very closely related and are probably the same species.

Now, what does all of this have to do with eels?

Well, I think we have to consider eels as fish. More specifically, I think we have to consider eels a commercial fish. Indeed, commericial fishing is really taking its toll on the European eel. Today, it is considered a critically endangered species, and it is on the ICUN Red List. Typically, the reasons for its decline are thought to be the building of dams on rivers, which preven the eels from returning to freshwater to spawn. PCB pollution has recently been blamed for crash in European eel populations.

The European eel is in such a bad state that Norway recently banned fishing for European eels in its waters.

However, there is another factor that has also harmed eel populations. They have been overfished. Eels have been a common “peasant food” throughout European history. In fact, it is only been recently that they have been elevated to fine French dining.

And what happens to all fish species when they are overfished? In virtually every case, the size has been greatly reduced. People take the big ones. One big fish is less labor intensive to land than a bunch of little ones. And let’s not forget that some people trophy fish out the large ones.

And very often, the reduced size in fish species is reported on the news, like this story on whale sharks, this story on Alaskan and Russian salmon (which have a the opposite life cycle of eels– returning from the sea to their natal streams to spawn), and this one which blames commercial fishing for reduced fish size.

The unofficial and unverified maximum length for a European eel is 79 inches (200.7 cm). Now, that’s not a 2o or 30 foot eel, which I don’t think is likely with this particular species. However, if true, that eel was over 6.5 feet long.

Perhaps before European eels were widely exploited as a food source, eels of this size or possibly larger existed in European waters. It is also possible that there could be a throwback or two that still remains in the European eel population. It is also possible that these large eels were more common in more recent decades in remote lakes and rivers. When holiday makers visited these lakes and rivers and encountered these relict populations of eels, they thought they were monsters.

Now, I don’t have hard evidence that eels were much larger in the past. Because they were thought of as a peasant food ( and I’m not blaming peasants for eating them–just for the record), it is unlikely than any good records of them were ever kept in those early years. We’ve only started to pay attention to them when we’ve come to realize that the European eel is now critically endangered. What records we do have come from the past couple of hundred years– centuries after they became common table fare. We may simply be basing our maximum size for the European eel on what is really a species on the brink.

The truth is that in the very near future there might not be any European eels of any size left. But I think it is a logical fallacy to assume that we can determine the maximum size of European eels from the current over-exploited population. Maybe in some remote lake or river, there are a few rather large eels remaining.

The giant eel theory is well worth exploring, but I think the evidence for it may disappear before any can be found, if that evidence hasn’t already disappeared through the centuries of overfishing.

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