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Teeth of the Lycaon

african wild dog dentition

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

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

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

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

megalodon

I lived through that great Shark Week debacle in 2014, when the usually fairly reputable Discovery Channel showed this bizarre pseudo-documentary called Megalodon: The Monster Shark Lives. I believe I watched all of five minutes of this monstrosity, and I knew that the thesis posited in the film, that there really still are Megalodon sharks swimming the seas, would be taken as fact by a certain percentage of the credulous public.

If such an animal really does still live in the ocean, then small to medium-size craft could be endanger at all times, but of course, no real evidence of late surviving Megalodon has ever been produced.

Indeed, when this documentary came out, I was quite aware that some shark specialists were doubtful that these large sharks survived into the Pleistocene.

Well, we now have some really good evidence, based upon an extensive re-evaluation of the fossil record of Megalodon sharks, that the species went extinct about 3.51 million years ago. It was previously believed that the species went extinct 2.6 million years ago, and recently, a supernova was suggested as the likely culprit.

However, this new date means that the supernova probably did kill off lots of large marine mammal, but the Megalodon had already been gone for about a million years before the supernova hit.

This new study, published in PeerJ, contends that the species became extinct as the modern great white shark spread over the world from its ancestral home in the Pacific Ocean. Great whites became widespread in the world’s oceans around 4 million years ago, and their spread roughly coincides with the new extinction date for the Megalodon.

The authors contend that the juveniles of the Megalodon were unable to compete with the adult great whites, and because a species cannot exist very long if its young never survive, the great white might very well be the culprit behind the extinction of the Megalodon.

So no, Megalodon doesn’t live. Jaws took it out long ago.

giant panda

Giant pandas are the last survivors of their entire lineage of bears.  The Ailuropodinae were once a diverse, mostly omnivorous lineage of bears that were widespread throughout Eurasia and North America during the Miocene.  About 2 million years ago, one extant line of these bears began to adapt to more herbivorous diet, and we believed that this shift to a more herbivorous diet was directly analogous to becoming a bamboo specialist.

The truth is no one ever looked at the carbon isotopes in ancient and modern panda remains to see exactly what when giant pandas became bamboo specialists. Well, a study just published in Current Biology has revealed something quite shocking.

The authors did look at the isotopes in several ancient pandas, including the modern species, but what they found was that the shift to a more vegetarian diet was probably accomplished by the Pliocene.

However, the bamboo specialization did not become established in modern pandas until between 5,000 to 6,000 years ago, roughly about the same time as the rise of the Indus Valley Civilization and the Ubaid Period of Mesopotamia.

This finding has some interesting implications. One is that specialization can happen relatively rapidly in the evolution of mammals.

The other is that specialization can be quite disastrous for a species. Evolution has no grand design, and if there were some kind of foresight in the whole enterprise. giant pandas would have been better of living generalist herbivores.

It is also not really clear what pushed giant pandas into this specialization. Maybe there was a massive range expansion of ungulate herbivores into their forests that pushed them towards that diet.  Maybe there were some human-related factors that led to this specialization.

The truth is we don’t know.

I do, however, have a big question:  Did the Qinling panda evolve the bamboo-specialist diet at the same time as other giant pandas?

The reason I ask is that full genome comparisons revealed that Qinling panda diverged from the other giant pandas 300,000 years ago?

That means that these two forms of giant panda split from each other long before this bamboo specialization. It seems to me that they would evolved this bamboo specialization independently of each other.

There are also fewer studies on Qinling pandas. There aren’t as many studies on this form of panda, and it might not be as bamboo-specialized as the most common form.

Very real conservation implications could come from this discovery.  This discovery means that we should be looking more carefully at the Qinling panda in the wild to see if its diet really is different. This study included only modern pandas from Sichuan, so it would be quite interesting to see what wild Qinling pandas isotopes are like.

So, yes, this is an amazing find, but it has very real implications for panda conservation. It could potentially add more evidence for the Qinling panda as a distinct (and thus very endangered) species if it is found that Qinling pandas have a more diverse diet.

And if they have the same diet, then this diet evolved in parallel between the common giant panda subspecies and the Qinling panda.

Which is pretty amazing that both extant forms of panda bet on this same limited niche.  And this is an odd fate for what were once wildly successful omnivorous bears across the Northern Hemisphere.

Evolution takes us on weird journeys, doesn’t it?

painted wolves

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

 

 

 

 

 

 

 

 

 

 

isle royale wolves

One of the classic studies in wildlife management happened on island in Lake Superior. Isle Royale, part of the state of Michigan but much closer to the state of Minnesota and Northwest Ontario, is home to a population of moose. These moose either swam across from Minnesota or were stocked there in the early 1900, and they found themselves in a paradise. No predators existed on the island, and the island was full of birch trees and aspen colonies.

Over time, the moose denuded the aspens and the birches, and they were forced to eat balsam fir. In 1949, when Lake Superior was frozen over, a pair of wolves crossed to Isle Royale, and they were the foundation for a wolf population that specialized in hunting moose.

This island became of interest to ecologists early on.  It had been made a national park in 1940, and as a national park, it has no permanent residents. Because wolves and moose live on the island without any chance of humans hunting them,  early predator-prey researchers went to the island to see if Paul Errington was right.

Paul Errington was professor of zoology at Iowa State University. He had studied bobwhite quail population dynamics while a student at the University of Wisconsin, during which time he became close friends with Aldo Leopold. Leopold was not faculty member, but Errington learned so much from him during his time at the university. Errington was

Errington’s most famous research was performed in the marshes of Iowa. There, he studied the population dynamics of muskrats and American mink. Muskrats, which are giant water voles, are a major prey source for the mink, and one would think that mink would severely reduce muskrat population. However, Errington’s research found that mink predation had no real depressive influence on muskrat numbers.  He found that the mink tended to take young and infirm. Most healthy muskrats  were generally left alone.

This research, which was published in 1943, was the hottest idea in the nascent science of ecology, and researchers were looking for places where this hypothesis could be tested on a grander scale.  Isle Royale fit the bill, and the first studies of wolf and moose dynamics on the island started in 1958.

Initially, the research found similar findings to Errington’s muskrat and mink study.  Moose and wolf populations fluctuated over the years. When the moose became too numerous, they were forced to eat more and more balsam fir. The fir is not nutritious, and the moose gradually become emaciated. Because the moose require lots of nutrition from their bones to grow their antlers, they also wind up suffering from arthritis.  Emaciated, arthritic moose are easy prey for wolves, and wolf numbers increased when the moose hit this stage.  The wolf population would then increase, and after a few years, it would begin to pare back the moose population to allow birches and aspen to recover.

But at the same time, there weren’t enough weak moose for the wolves to hunt, and the wolf population would crash. The moose would find themselves in a situation with more limited predation and better forage, and their numbers would increase again. And the cycle would start again

When I think of Isle Royale’s wolf and moose dynamics, I think of the work of Rolf Peterson, who made a career out of studying the wolf and moose population fluctuations.  He began to notice that the balsam firs on the island were not regenerating through each moose and wolf fluctuation.

These findings meant that Isle Royale would not be able to continue on through constant moose and wolf fluctuations as one might have hoped, and this problem became worse when the wolf population really crashed.

Lots of debate exists about how well wolves can withstand inbreeding. Climate change has meant that ice bridges that connect the island to Minnesota and Ontario no longer form, and those that do form aren’t around very long. So the wolves have been inbreeding on the island for decades. They were able to withstand this inbreeding for decades, but in the 1990s, the population really began to suffer from this inbreeding depression.

In 1997, a lone male wolf, “Old Gray Guy,” wandered onto the island, there was hope that his genes would be a genetic rescue on the island.  He apparently did introduce some much needed genetic diversity to the island, because by the 2010s, 56 percent of all wolf genes on the island could be traced to him. Wolf fertility did not increase as the result of his arrival, and although a debate exists as to whether there was anything like a genetic rescue on the island, it should be noted that Old Gray Guy was very much like a popular sire in a purebred dog. The population was already quite inbred, and the influx of only a single male that winds up contributing that many genes to the population isn’t going to save the population

By the first decade of this century, a genetic disorder of the wolves’ spines became rampant in the population.  The wolves began to die at early ages, simply because they were unable to walk or because movement was painful for them.

At that time, a real debate existed about bringing in wolves from the mainland, but caution was exercised. There was a hope that natural selection would purge the spinal deformities, but this purge never came. When the ice bridge formed during a polar vortex collapse in 2014, there was also real hope that wolves would walk over to the island. However, all that happened was that two Isle Royale wolves left the island, and one was found dead on the Minnesota mainland.

Further, because the purpose of the studies on wolves and moose on Isle Royale was to see what predator and prey relations are like without the use of human intervention, there was very real resistance to introducing more mainland wolves.

However by December 2017, only one wolf was thought to be living on the island, and the moose population exploded.   However, the moose themselves were physically smaller and would very likely eat themselves out of forage in short order.

This past September, a plan was hatched to restore the wolf population to Isle Royale.  Wolves from the UP of Michigan and northeastern Minnesota would be released upon the island.  Yes, after decades of allowing nature to take its course, man would finally intervene in these predator-prey dynamics.

Things are not off to a good start, however.  One of the first three wolves released on the island has already used the formation of an ice bridge in the most recent polar vortex collapse to escape back to the Minnesota mainland.

However, wildlife managers aren’t giving up. Currently, there are plans to release six wolves from Ontario’s Michipicoten Island onto Isle Royale.  These wolves, which also live on an island in Lake Superior, have a bit of a storied reputation.

On their island, there was once a thriving population of woodland caribou, but the wolves have reduced their number from over 900 to just 30 individuals.  The  caribou were not native to the island, however.  A bull just happened to pop up on the island, and other woodland caribou were stocked to create a population, which thrived until the winter of 2014-2015.

That is when wolves walked across an ice bridge n Michipicoten, and they found it a paradise for wolves. Finding a vast horde of ungulates was a boon for their numbers, but by it took them just a few years to drop the caribou numbers. The caribou are now being taken off the island, but the wolves have had virtually no options. the wolves have had virtually no options.

These Michipicoten wolves are large-bodied creatures that definitely have the ability to hunt large ungulates, so there are very real hopes that these wolves will be able to reduce Isle Royale’s moose population.  New studies on their population dynamics can begin, and this experiment continues on.

That is the hope, anyway.  Whatever happens in the next few months, it should be noted that Isle Royale and the related Michipicoten experiences is that both are studies in a really controlled environments that no longer exist in North America, if they ever did at all.

Moose, caribou, and wolves are all at the mercy of a human-dominated world.  These islands give us an idea of what the world would be like if predator and prey dynamics were left alone, but they aren’t necessarily indicative of how these dynamics would exist on a continent in which human interests have great knock-off effects upon ecology.

After all, the Isle Royale moose and wolves are not directly affected by human hunting. They are still controlled by climate change.  Warmer than normal winters mean that the ice bridges don’t form, and the collapse of the polar vortex, which is also caused by climate change, means that the inbred wolves just don’t want to stay on the island. Moose are getting weaker and weaker as the ticks spread through the populations, and without long periods of cold, the ticks are able to infest the moose, weakening them in greater numbers every year.

The Isle Royale studies are the studies of an island where hunting isn’t allowed, but virtually every place where wolves and ungulates exist on this continent, hunting is a major point of human interest. Humans want more ungulates on the ground, and if their numbers ever drop, wolves will be blamed.  Wolves certainly can have an effect upon prey numbers, and even more than that, they have an effect upon prey behavior. Trophy cervids are just harder to kill if they spend much of the year being harried and herded by wolves.

Maybe what we can know from Isle Royale is limited, but in those limitations, we might get an idea of how to mitigate all these competing interests and have some way of keeping large predators as part of our North American wildlife heritage.

If wolves are not restored to Isle Royale, the landscape will likely be denuded of trees, and all that will be left is a population of tick-invested, diminutive moose.  They will always be on the edge of famine.

Restoring wolves gives a potential hope, but nothing is guaranteed.

But the saga goes on. Maybe for just a bit longer, or maybe new, bright future exists for this most storied of predator and prey studies.

 

 

 

poet snuggle

I must admit that I never really new sighthounds other than retired racing greyhounds until these past few months.  I knew that Jenna had a special relationship with Zoom, her cream and white whippet, and when we moved in together, she had just brought in a brindle and white whippet puppet.

I figured that the puppy would wind up being her dog, and although I was quite aware that whippets were quite trainable dogs, I never really thought I’d become attached to one.

As Poet has matured, though, he and I have drawn closer to each other. It was he who made the first mood.  A few months ago, he just sort of declared in his subtle sighthound ways that he was my dog, end of discussion.

And I’ve accepted the arrangement. I have found him to be as biddable as any golden retriever, and I have trained him to sit, heel, lie down, stand, and speak. He fetches the ball like a demon, which is to be expected. His father is a Frisbee nut.

He likes to go with me everywhere, and because he’s smaller and innocuous, I generally don’t have a lot of trouble taking him places.  He is genteel and kind, but he is not demonstrative with strangers.

Through one family line I trace to the rugged counties of Lancashire and Yorkshire, the same counties that spawned the modern whippet as a rag racer. I suspect my Quaker ancestors in that part of the world may have had little greyhounds much like whippets, perhaps to fill the pot with rabbit stew on cold winter nights.

So we are now attached to each other. I have a nice little whippet with a show and coursing career ahead of him, and I now know the full appeal of this breed. Once they choose their person, you are it.  No one else really matters.

And that is strange and moving feeling, especially when you’re used to golden retrievers that are so socially open.

Poet is my little boy. My little whip. And I am his person.

 

 

smithsonian wolf

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

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

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

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

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

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

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

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

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

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

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

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

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

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

 

 

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