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Posts Tagged ‘endangered species’

Twenty years ago, things seemed great for the Tasmanian devil.

The species had rebounded from several decades of intense persecution. It was originally believed that Tasmanian devils were a major threat to sheep, and from about 1830 to 1936, they were relentlessly hunted, trapped, and poisoned. Bounty systems were implemented, and their number did drop during that time period.

In 1936, Tasmania offered full protection to the Thylacine, which had become quite scarce in the wild. Because the devil was also quite uncommon, protection was offered to that species in 1941.

From 1941 until the 1960’s, the devils were allowed to exist without any sort of hunting pressure. And the numbers began to increase again. Occasionally, poisoning permits were issues to control devils in sheep production zones, but the animals were still officially protected.

By the 1970’s, there were concerns that the devils were overpopulated.  In 1975, the population crashed, but it then rebounded. It continued to grow until 1987, when another crash happened. These sorts of boom and bust growth cycles exist in virtually all wildlife species, and it was assumed that the devils were developing along healthy lines.

Tasmania allowed permits to cull devils until the early 90’s.

Then in 1996, all hell broke loose for the devils. A contagious form of cancer was discovered. Called devil facial tumour [tumor] disease, it was originally believed to be caused virus. It is now founded to the result of a clone of malignant cells. It is transmitted with the devils fight over carcasses, which they are so famous for doing.

The devils are highly susceptible to this cancer. Since 1996, the devil population has crashed by 80 percent. Almost all of the loss is attributed to this disease. It is estimated that if the disease continues as it is now, the Tasmanian devil will be extinct in 25 years.

Why would the devils be so susceptible to this unusual cancer?

Well. It was always noted that devils were unusually susceptible to other forms of cancer. Cancer has always been a major cause of death in the populations that have rebounded since the devil was protected in 1941.

The reason for this susceptibility to cancer and to this particular form of cancer is really quite simple. Diversity in the genes in the MHC class I and II in Tasmanian devils is very low.

Devils have very low genetic diversity. There are certain reasons for this low diversity. One of these is that the Tasmanian devil in Tasmania is relict population. The animals were once found throughout Australia, but it is now represented only by population that became isolated on an island.

And this population experienced an extreme genetic bottleneck 10,000 years ago. The founding population that survived that bottleneck could have been as few as 500 individuals. This bottleneck has been exacerbated through intense persecution since Europeans arrived on the island, and because the MHC diversity was always compromised, the devils were often experiencing epidemics.  It is thought that two population crashes that occurred in the first half of the twentieth century were the result of epidemics that rapidly spread through the genetically depauperate devils.

We are no longer talking about devils being overpopulated as they possibly were in the 1970’s and 80’s. We are now talking about possible extinction.

And it’s all because of inbreeding– inbreeding caused by natural causes 10,000 years ago and more recent inbreeding that has occurred because of intense persecution and habitat fragmentation.

This story should be a cautionary tale.

Just because a species has appeared to recover in numbers does not mean that all is well.

We have to pay attention to diversity within the MHC.

Many endangered species are in exactly the same position as the Tasmanian devil. Cheetahs are famously inbred, but thus far, no major disease has popped up that will kill them all. That does not mean that it won’t. It just means that it could easily happen.

And even our success stories might not be so successful.

In the US, we like to congratulate ourselves about the successful recovery of the northern elephant seal. In the early twentieth century, there could have been as few as 100 northern elephant seals left. The Mexican government protected the only surviving colony, and the US soon followed suit. Eventually, their numbers reached over 100,000 individuals. These are harem breeders, which means that only a few males produce offspring every generation. They suffer a definite popular sire effect, which wouldn’t be so bad if they weren’t already so inbred.

No bad diseases have popped up in these animals yet. However, one easily could.

As the devils have taught us, just because a species is particularly numerous does not mean it is not vulnerable. We have to pay attention to genetic diversity, especially in the MHC genes.

Unfortunately, many success stories in conserving wildlife species are likely to be similar to that of the Tasmanian devil. Genetic bottlenecks create small founder populations that may be able to recover in very large numbers, but because these populations have low genetic diversity, they are unable to survive epidemics.

This is why conservationist are so concerned with genetic diversity in all sorts of wild populations and within the zoo breeding programs. Genetic diversity is essential for endangered species to fully recover. Otherwise, they will always be vulnerable.

And if they are that vulnerable, how can we say that they have fully recovered? If one contagious disease can do this to the Tasmanian devil, what can another one do to the California condor, the Florida panther, or the giant panda?

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Jess at DesertWindHounds discusses the importance off genetic diversity in the Major Histocompatibility Complex (MHC),  a gene family that controls immune responses. In dogs, it’s called the Dog Leukocyte Antigen (DLA) system

It’s very important that everyone in dogs understands these concepts.

In fact, it’s very important that everyone interested in conservation of endangered species or in breeding any kind of animal has a full grasp of the problems that can happen with reduced diversity in the MHC.

This angelfish website also partly discusses the MHC. Unlike Jess’s post, it is pro-inbreeding, but the author recognizes the need to bring new blood in.

The problem with dogs is we are operating within a closed registry or a Potemkin open registry system where new blood is not easily brought in.

And with virtually all Western breeds, all individuals within a breed are derived from the same founders.

The is the big problem with line-breeding, inbreeding, and using just a few sires  per generation within a closed registry system. At some point, the breed becomes too homozygous within the MHC/DLA, and it’s screwed when a really bad disease pops up.

My guess is we’re going to hear a lot about the MHC in the near future. Many success stories of recovering endangered species are going to turn into disasters.  Some species have recovered from a very low founding population, and that means that they don’t have much variation at all in their MHC.

That’s bad.

And there is one animal right now that recovered from intense persecution in its homeland. It was eventally protected, and its numbers grew.

But now because of a communicable disease, it may very well go extinct. As a species, it has low genetic diversity and very little variation in the MHC. If it does become extinct, it will be this compromised genetic diversity that ultimately does it in. If it had more diversity in its MHC, then some individuals might have a some immunity to it, but thus far, all have been found to be highly susceptible to this disease.

I’ll reveal that animal and its disease  tomorrow in a longer post.

Until then, read this post and get a good understanding of what the issues are.

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This is an Arabian wolf (Canis lupus arabs). It is a wolf that is very similar to a dingo.

As regular readers of this blog know, I am generally opposed to splitting up species, unless  a very, very good reason is given.

For example, I can see that coyotes, golden jackals, and wolves are different species. Although capable of interbreeding and producing fertile offspring, these animals normally don’t hybridize. The evidence is clear that they split from common ancestors millions of years ago, and they maintain very clearly different ecological niches.

But when you start talking wolves and dogs, I see far fewer differences, especially when one considers how diverse wild wolves are and have been through their evolutionary history. It is intellectually dishonest and misleading to base all comparisons between wolves and dogs by using the big game hunting wolves from Alaska and Northern Canada as the wolf from which all analogies are made.

Those wolves are actually quite specialized– every bit as much specialized as a border collie, a golden retriever, or a pointer.

Keep mind that in the Middle East, there are very dog-like wolves. The subspecies is called Canis lupus arabs. Except for color, it very strongly resembles the dingo of Australia, which is often considered a “primitive” form of domestic. (I consider it a domestic dog that has fully returned to the pack-hunting wolf culture and ecological niche).

As has recently been revealed, dogs were originally domesticated in the Middle East, and it is likely that if we want to make comparisons, we should be looking at C. l. arabs, not all of these moose and muskox hunters. No serious authority considers C.l. arabs a distinct species, so I am not about to consider the validity of Canis familiaris.

It’s a silly name.  The differences between dogs and any wolves are no more extreme than the differences between Eurasian wild boar and domestic pigs or between domestic cattle and the extinct aurochsen.  We don’t consider domestic mallards to be different from wild ones, even though we have call ducks and Rouen ducks that are very different from the original wild form.

I think it’s just that we still have mental blocks about wolves that we cannot accept that they might be the same species as the creature with which we share our homes. A wolf is a wild thing that cannot be controlled, but a dog, well, a dog is something that can be controlled.  It’s just a degenerate wolf that evolved to eat human feces and garbage.

There are certain arguments that need to be considered when thinking of where dogs and wolves fit together. Dog and wolf are not the same as wolf and coyote and wolf and golden jackal.

Dogs did not split from wolves millions of years ago. It was a much later split, and the split has not been complete.  The black coloration in wolves has been traced to genes that originated in domestic dogs.  I have found extensive historical records of dogs and wolves mating on the North American frontier. Essentially, without persecution to distort wolf behavior and genetics and without the presence of other domestic animals that require people to protect them from wolves, dogs and wolves are more than willing to get together.

But what about ecology? Don’t dogs and wolves have different ecological niches that make them separate species? That is also not a particularly convincing argument.

In the case of the dingo, these animals have returned to the wolf culture and ecological niche. They hunt large game in packs and act the top predator in their native country. Wolves in Italy might as well be dogs, because they live exactly as stray dogs do throughout the world. They don’t hunt much. Prey simply isn’t around, so they move into garbage dumps to find food. That is exactly the same ecological niche we see in most free-roaming domestic dogs.

Dogs and wolves are capable of adapting their cultures to the ecology of their particular situations. Within their genome is an ability to adapt their body types very to fit their particular situation. Wolves that hunt moose get very large. Their jaws become very powerful.  Wolves that hunt mostly small game never develop those traits. Their jaws are weaker, and they learn how to forage on their own, as is the case in the aforementioned Arabian wolves.

We underestimate the ability of C. lupus to adapt its behavior and its physical traits at our own peril. It is something we cannot understand. We are not that physically different from each other, so we assume that other species are similar. It’s very hard for some to accept that Pekingeses and Arctic wolves are part of the same species.

It’s not very hard for me.

And when I think about it, I am even more deeply amazing at the species with which we share our lives.

What has been written above is an intellectual exercise. Taxonomic debates and analysis often are, and when we consider the exact taxonomy of the genus Canis, debate is automatically going to be in the offing.

But this debate has certain practical realities, which can actually harm conservation efforts.

Wolves are a good example. Not only are dogs often considered a separate species, but several wolves are considered distinct enough to have their own species status.

The red wolf is the most famous one. Too much has been written on that particular animal, so I’m not going to waste a lot of time on that one. I will say that I am of the view that it is the result of hybridization between C. lupus and Canis latrans. Some evidence suggests that this hybridization happened in recent times. However, there are theories that they represent an ancient hybrid or are some form of ancient wolf that evolved solely in North America.

I’m not going to go into this one, but I do know red wolves behave like C. lupus and not like coyotes. However, we are spending lots of time and money trying to keep red wolves from mating with coyotes.

Just out of tradition, I consider them to be part of C. lupus, along with C. lupus lycaon, the timber wolf or Eastern Canadian wolf. Some authorities believe that these animals are the result of hybridizaton between C. lupus and the coyote. Others consider them to be the northern population of the red wolf, if they also count the red wolf as a distinct species.

These are probably the best known wolves with undetermined taxonomy, but just a few years ago, it was decided that the Indian wolf (C.l. pallipes) and the Himalayan wolf (C. l. himalayensis) are also distinct species.

Considering these animals to be distinct species does have some practical political benefits. After all, it is easy to get people worked up about protecting a distinct species than a mere subspecies.  Legally, it is called the Endangered Species Act, not the Endangered Species and Subspecies Act, although conservationists do try to preserve the distinct subspecies for a particular ecosystem.

And maybe that is a good thing that we can get attention focused on preserving a population of unique animals.

However, there are situations in which splitting up a species is nothing more than a good way to kill it.

I am reminded of the recent finding that has led some to count the northern white rhino as a distinct species from the southern white rhino. The southern white is a relatively healthy species. If a species of rhinoceros is going last through the next few centuries, it will be this one. The northern white rhino is extinct in the wild, and only a few individuals exist at the San Diego Wild Animal Park and a zoo in the Czech Republic.

(Four of the six Czech rhinos have since been sent to the Ol Pjejeta Conservancy in Kenya, where they could be very useful in preserving their species. I have not heard whether they will be allowed to interbreed with southern white rhinos or not. I hope that it at least gets considered. You can support Ol Pejeta’s efforts here.  )

It could possibly be preserved through some cross-breeding, and such cross-breeding has been employed in the past. I believe the Przewalski’s horse was essentially save through the influx of some domestic horse blood. However, Przewalski’s horse is now regarded as a subspecies of the wild horse from which the domestic horse descends– even though it has a different chromosome number.

The reason why we spend so much money preserving red wolves from coyotes is that we can’t conserve hybrids. People also worry about dingoes crossing with Western domestic dogs all the the time. There is an obsession with trying to find and preserve pure dingoes.

In weird way, this strarts to resemble something else.

Something I’ve always believed was more than a bit detrimental to domestic animals.

It is this desire to have purity for purity’s sake.

If we decide that some animals are distinct species and can never be crossbred, then we’ve essentially doomed them to extinction.

Of course, there are legal reasons for doing so. Blood purity problems plagued some of introductions. When a study came out about the hybrid origins of the red wolf,  various wolf haters called foul.  That is one reason why the Ghost Ranch Mexican wolves were deemed unsuitable for reintroduction. The possible taint of their bloodline meant that the wolf haters would be empowered.

I know that conservationist are much more concered with genetic diversity than breeders of purebred domestic animals. That’s an obvious difference between the two groups.

However, it is possible that splitting up species because of some unique genetic characteristic could have disastrous genetic consequences.

I can see that possibility that all of this splitting actually winds up creating situations that are akin to breeds of domestic dog. That is something that species with very limited populations really don’t need.

And it would be worse than the situations that exist within the closed registry system in domestic dogs. It is one thing to breed a golden retriever to a poodle. It is quite another to breed two species together that we have decided must be distinct enough to be different species.

Evolution has never embraced blood purity. That is a human construct. Nature has shown us that time and again, species have evolved through the influx of genes from another.

Including ours.

There is some evidence that after our ancestors split from the ancestors of the chimps and bonobos that our ancestors interbred with their ancestors again.

Species often are able to adapt and develop sustainable gene pools when natural gene flows are allowed to happen.

Such an idea is very hard for people to understand.

We like clear differences between ideas and concepts.

But in nature things are often nuanced and gray. The stark differences we expect and need for our understanding often aren’t there. Things that look clear  and distinct are actually quite smudged.

And when we try to create distinctions, we wind up with some real problems.

Our brains like distinctions, but the world is not as distinct as we like it.

How we answer these questions ultimately will affect how we create conservation strategies.

We can use the knowledge we have to preserve as much biodiversity as we can.

It may mean that we turn off that part in our brains that wants complete and total distinctions for the sake of preserving genetic diversity of certain species.

It does us no good to do to endangered species what we have done to our domestic animals.

It’s not good for our dogs, and it could be a killer for so many species.

This is a tendency that should be checked–or at the very least, kept in perspective.

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sleeping dhole

It was a dhole (Cuon alpinus)– literally “mountain dog.”

This animal is also known as the red dog, the Asiatic wild dog, or the Indian wild dog. Its range is not restricted to India, but that is where it was probably first encountered by British zoologists. However, its range extended through Asia into the Russian Far East and Siberia in historic times, and the animals proably still live there in small, relict populations.  Originally though, dholes were found throughout Eurasia and even parts of North America. Yes, there were once dholes in North America.

These are pack hunting dogs, just like certain members of the genus Canis and the African wild dog (or as I call it –“the painted wolf,” which is a literal translation of its scientific name.)  The best way to understand where it fits in terms of taxonomy is that it is like that of the harlequin-splotched painted wolf. It is relative of Canis.

The dhole and the African wild dog are derived from the ancestral line that gave us the animals in the genus Canis. However, they are genetically quite distinct.

The two species are similar in their behavior. They both live in packs and hunt large game, just like wolves and Eastern coyotes (and some feral domestic dogs.)  What’s interesting, though, is that dholes and painted wolves aren’t that closely related– no more than they are related to wolves and coyotes.

It’s very likely that these animals developed pack hunting as a result of parallel evolution.  Pack forming behavior in wild dogs is generally associated with wild dog species that need to kill large prey species. (Some exceptions to this rule exist. Ethiopian wolves live in large packs, but they don’t hunt any large game. They live mostly on rodents. The Bush dog of South America also forms large packs, but because they weigh 15 pounds at most, the size of their prey is greatly limited. Also, jackals will hunt in packs, as will Western and Southern subspecies of coyotes under certain circumstances.)

Now, lots of legends have developed about dholes. One of these is that they are a major threat to wolves. The reason why this legend even developed is that dholes form larger packs than wolves do. They have been seen in groups number up to 40 individuals. However, dholes are coyote-sized,  and are generally very nervous and secretive animals. It is very unlikely that they would be a major threat to wolves. If the two are in the same area, it is much more likely that wolves would have the upper hand, despite the size of the dhole’s packs.

This legend is even more embellished in the story “Red Dog” from Kipling’s The Second Jungle Book. When I first read that particularly story as a young boy, I thought of the red dogs as a swarming horde of pillaging jungle curs. I later looked up the exact species, because I thought Kipling was writing about an animal from mythology. Well, the animal in question was real, but the behavior of the dhole n the Kipling story was mythological. Real dholes don’t act anything like the red dogs.

Dholes have a few other interesting traits. They make lots of weird noises. They make whistle-calls to each other in the forest. They also cluck and mew.

I’ve always found dholes rather interesting. If you want to find out more about them, check out The Dhole Home Page. The numbers of dhole continue to drop throughout its range.  These animals need lots of habitat to survive, and that habitat is under threat from increasing human populations and increased over-exploitation of natural resources (especially logging) in the dhole’s range. In some parts of their range, dholes are seen as a threat to livestock, so they are poisoned and shot. They are also caught in snares set for other animals.

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Dholes are actually easier to domesticate than wolves. If captured as small pups, they can become quite tame. Historically, forest dwelling peoples in the dhole’s range have driven it off its kills and taken the meat for themselves, for it was well-known that dholes are not aggressive in defending their food. Because they were so passive and so easily tamed, the British naturalist and ethnologist Brian Houghton Hodgson believed that the dhole, which he called Canis primaevus,  was the ancestor of the domestic dog. He claimed that the head was also very similar to the domestic dog, although if one looks at a dhole’s teeth, they are very different from any other species of dog. Hodgson kept several as pets, and he found them as trainable as domestic dogs. After all, aren’t most “primitive” Asian dogs red in color?

Now, of course, that’s all nonsense. But it’s interesting that one could tame the dholes. I’ve also read of accounts of pariah dogs (the Indian equivalent of dingoes) hunting in packs that include dholes.

Dholes are not the ancestors of the domestic dog, but accounts like these does lead me to wonder why man never domesticated the dhole. Why was the wolf the animal that man domesticated?

Maybe wolves were originally dhole-like, and maybe they were originally very curious about people. The fact that dholes live in huge packs tells us that they are socially quite tolerant animals. And accounts of unexploited packs of North American wolves in the early nineteenth century seem to point to the fact that wolves were once similarly socially tolerant. The size of those wolf packs mirrors those of modern dholes. Perhaps they were like dholes in that they were very easy to approach and easy to socialize and imprint when very young.

Modern wolves then underwent a selection for the exact opposite behavior when we began our widespread, almost paranoid, persecution of that species. By killing them using so many different poisons and traps, we made sure that the only wolves left in the gene pool were very fearful, cautious, and emotionally reactive. And that’s why modern wolves are so difficult to tame, and why they are such unsuitable pets.

I don’t have any hard answers, but I do think that wolves had to have been so easy to domesticate that a cave man could do it.

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Yesterday’s Critter

ghara

Yesterday’s critter was a gharial. Not only that, it was a male gharial.

How do I know?

Well, male gharials have bulbous lump on the end of their snouts. It’s called a ghara.

In fact that’s how the animal got its name. In one of the Indian languages, ghara means “pot.” The bulbous lump on the males does look a bit like a pot.

Now, in the comments, virtually everyone got it right.

However, I bet you didn’t realize how big one of these crocodilians can get.

The males have been known to exceed 20 feet in length, and there is even a record of 23 footer killed in the River Kosi in Bihar, which makes them as long as the longest saltwater and Nile crocodiles.

Unlike those creatures, however, the gharial is not a threat humans. Although they can bite and slash with their teeth, their jaws are too weak to really damage a person.  As a result, they don’t consider large mammals to be prey. Indeed, they live almost entirely on fish, which is why they have needle-like teeth. They need them to hold on to slimy fish. Those teeth are poorly designed to grip the leg of a human or any other large mammal.

I first saw a gharial at the Cincinnati Zoo when I was probably 5 or 6 years old.

And then I saw a Nature (with George Page) documentary about them, and they had me totally fascinated. It turns out that gharials are in a lot of trouble. They need clean, clear water in which to fish, and clean and clear water is very hard to find on the Indian subcontinet these days.

Attempts at stocking captive-bred gharials in the wild have not been that succesful.  The animals were found to be unable to handle heavy metals in the water, and that’s a very bad sign for the gharial’s future.

They are strange looking, but they aren’t a threat to man. They may look like river monsters from some horror movie, but they are nothing more than harmless fishermen.

It would be a tragedy if these crocodilians disappeared from the earth forever. However, they probably won’t. They do breed in captivity, and I’ve seen them at more than one zoo. But that would be a sad state of affairs if the only gharials in existence in the world were in zoos.

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loggerhead-shrike

Let’s say we have an island with two endangered species living on it. This situation isn’t hard to imagine. Lots of islands have their own endemic native species that are very often endangered. Most island jurisdictions do all they can to protect their endemic wildlife.

But here’s the twist: Let’s say it has been determined one of those endangered species might be a major factor for mortality in the other endangered species. What do you do?

Well, we do have a real case in which one endangered species is harming the population of another. On San Clemente Island, the local subspecies of the island fox is preying upon an endangered subspecies of Loggerhead Shrike.

In the 90’s, it looked like the San Clemente Loggerhead Shrike was on its way to extinction.

Because the foxes are also quite endangered, there was little that could be done to reduce fox numbers.

However, a plan was devised and implemented in 1998 to solve the fox predation problem. The first part of this plan was to trap the foxes and hold them until the shrike breeding season was over. The second part involved the building of an electric fence around the shrike nests.

But the third part of the plan was the most novel.

E-collars have been part of dog training for a very long time. These collars are often employed to keep dogs from running deer and to generally control predatory behavior. A similar collar is also used as an invisible fence to contain dogs to their owners’ yards.

It was decided that these collars could also be used to train the foxes to leave the shrikes alone.  The foxes were trapped and fitted with e-collars that could be activated when they approached an antenna sensor. It was the invisible fence to protect the shrikes. If a fox approached the trees where the shrikes were nesting, it got shocked. (These foxes, like their mainland relatives, can climb trees to raid bird nests.)

When this three pronged plan was implemented in 1998, the shrikes had a successful nesting season, and no foxes had to be killed to save the shrikes– thanks to a little “shock therapy.”

(In case you didn’t know, island foxes are native the Channel Islands off the coast of California. They are very closely related to the more common gray fox.)

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The mystery beast was a giant panda cub.

The mystery beast was a giant panda cub.

The orignal post was here. Giant panda cubs, like all bears, are born in a relatively underdeveloped state, much less devoped than puppies are. These panda cubs are being bred in captivity in many zoos throughout the world. However, the biggest panda breeding center is the Wolong Giant Panda Breeding Centre.  This center has perfected panda breeding and has even come up with a way of doubling its success.

Giant pandas usually give birth to twins. However, the female typically will raise only one cub. The Wolong panda experts take that abandoned twin and raise it. In this way, they double the number of pandas produced.

If you look closely at the original post’s picture, you’ll notice that the feet are really unusual, even for a bear. Pandas actually have a wrist. It is actually a modified sesamoid bone that allows the panda to grip its food, which is mostly bamboo.

BTW, giant pandas are bears. They are one of the most primitive species of bear, but they are bears nonetheless. Studies of their molecular evolution have satisfied that they are bears.

The red panda has a similar wrist, and it does eat bamboo. However, it is now thought to either be a member of the raccoon family or a member of its own family. The evidence for the latter, I think, is stronger.

Although the adult giant pandas do look cute, they can be aggressive, especially captive ones. A giant panda recently bit someone in China, who entered the panda’s enclosure. This panda had bitten two other people previously.

And then there’s always this footage:

From the youtube user krzychuthc92

Moral of the story, don’t sit too close to the panda cage!

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axolotl

 

The axolotl is a species of tiger salamander that is found the lakes around Mexico City. It is a neotenous species of tiger salamander, retraining its gills throughout its life. It can be stimulated into metamorphosis, if certain hormones are introduced into its system or if it gets iodine treatments. The British naturalist Julian Huxley was among the first to cause metamorphosis in the axolotl using hormones. However, the metamorphosed axolotl is an unhealthy creature that lives only a year or two afterward.  This lifespan is greatly shortened from the 10-15 years it would have experienced as a neotenous specimen.

They are found in these lakes, which are polluted, but pollution alone has not killed off the Axolotl. Carp and tilapia have been introduced. These fish have discovered tha Axolotl larvae are a good source of protein, and the axolotl cannot survive this level of predation.

Interestingly, even if this species went extinct in the wild, it would not be extinct in captivity. In fact, you can buy axolotls as pets, which are kept a diet of bloodworms, salmon pellets, and other food for carnivorous fish. It has been in capitivy for so long that different color morphs have been produced, including albino, yellow albino, and leucistic (like the one pictured at the top of the post).

The animal has some cultural significance for Mexican of Aztec ancestry, because the axolotl is the representation of the Aztec deity, Xolotl, the dog-headed deity of death. Xolotl feared he was about to be banished, so he turned himself into the salamander and hid in the lakes. (This story might explain why an unrelated but similar looking species of gilled salamander in the US is called a “water dog.”)

More information can be found here.

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