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Archive for February, 2019

black coyote

For most of my life, scientists believed that the present era was still the Holocene.  Glaciers retreated with a global warming trend around 11, 650. Man went from being the apex predator over much of the world and became the apex consumer. Agriculture allowed our populations to expand, and we started to give up our wandering ways and became “civilized.”

It was generally believed that the past few centuries are but a continuation of this age, but now a growing number of scientists believe we have left the Holocene and entered into the Anthropocene. Several scholars have issues with this new distinction, but I think it is quite useful. In this era, human activity is the main factor affecting climate and ecology, which is why the age is named for the Greek word for human (anthropos).

The best argument I’ve seen for when this era began is 1610.  In this scenario, the era is dated to when European disease and conquest killed off enough Native Americans and enslaved and enough African had been enslaved to allow forests to grow back in former agrarian fields.  This process started in 1492, but by 1610, enough of those trees had grown to remove enough carbon dioxide from the atmosphere to push the planet into the Little Ice Age.

Darcy Morey and Rujana Jeger have a great model for understanding dog domestication as a change in trophic strategies.  In the Pleistocene ecosystems, most wolves were mesopredators, playing second fiddle to an ecosystem full of cave lions, machairodonts, large bears, and cave hyenas. When these wolves hooked up with people, though, they hitched their wagon to the species that often behaved as the apex predators in the ecosystems.  When humans switched to agrarian lifestyles during the Holocene, humans became apex consumers, and dogs joined us as beneficiaries of being allied to that apex consumer species.  During the Holocene, many wolves became apex predators, as the cave lions and other large predators became extinct.

I’ve always liked the framework that Morey and Jeger derived in this paper, but now that we’re entering into a new geological age, maybe we need to look at the change in trophic strategies of wolves in this new age.

Morey and Jeger don’t have a good framework for what happened to wolves in the Anthropocene, but across Eurasia and North America, wolves were gone from many human-dominated landscapes by the first decades of the twentieth century.  They existed only in isolated areas in Western Europe, and in the  lower 48 states of the US, they lived only in Minnesota and in an isolated region in East Texas and Louisiana, where the taxonomically controversially red wolves were located.

Large pack-hunting wolves were really in quite a bit of trouble.  In the United States, the coyote population began to expand out of its Western core range into the Great Lakes States. They eventually made to New England and the Maritimes of Canada, and they hybridized with relict wolves and the expanding population of domestic dogs.  Coyotes eventually colonized all the Eastern states, and as they did so, they largely became the apex predators in many parts of their range.

But in the 1960s, attitudes about wolves began to change. Many nations protected wolves, and there were often introduction plans in the works.  By the early decades of the twenty-first century, wolves were making significant comebacks in Germany and Italy. The wolves in Italy were often living very much like stray domestic dogs, living large at garbage dumps. Wolves live near large cities in Germany, and how these wolves are going to adapt to living in such human dominated environments is going to be a major question for researchers.

And in throughout Eurasia, we began to see that domestic dogs were mating with wolves.  Indeed, it is now estimated that a majority of wolves in Eurasia have relatively recent dog ancestry. 

Similarly, as coyotes expanded in North America, their genes began to work their way into the wolf population.  Yes, coyotes in a large part of the US have wolf ancestry, but we also have discovered that wolves across North America have coyote ancestry. Indeed, one interesting thing about these genome comparisons is that coyotes and wolves are much more closely related than we initially gleaned form mitochondrial DNA analysis. The calculation is that the gray wolf and the coyote last shared a common ancestor around 50,000 years ago.  This recent common ancestry has a taxonomic implication, which is that coyotes are themselves a divergent form of gray wolf in much the same way domestic dogs are.

In the Anthropocene, the wolves that have done the best have been the domestic dog and the coyote. The domestic dog’s ability to ingratiate itself into human society or live very nicely as an opportunistic scavenger/hunter on the periphery of humanity is a great gift.  The coyote can live as an opportunistic scavenger/hunter as well, and it also can live very nicely as a mousing fox or pack up and hunt deer.

Gene flow among wolves, coyotes, and dogs has made these entities much more fuzzy than we once thought they were. Dog genes are working their way into both the coyote and wolf population.  Strange pelt colors are popping up in the wild animals. The black coloration in domestic dogs was conferred onto the North American wolf population during the Holocene, but this same mutation for melanism has entered the coyote and Italian wolf population in very recent years. Dogs have introduced dewclaws on the hindlegs to some wolf populations, and I have seen photos of Eastern coyotes that have those hind dewclaws as well, which likely were introduced through breeding with domestic dogs.

Coyotes in the East are evolving larger size to become better predators of deer, but becoming larger and more effective ungulate hunters will have a trade-off. As carnivorous mammals grow larger, they become more and more dependent upon large prey to survive.  Very large wolf-like coyotes will lose their ability to live well on small prey and garbage.

So in the Anthropocene, dogs remain allied to the apex consumers. Some coyotes operate as apex predators, and some wolves live as opportunistic scavengers.

And as these creatures adjust their trophic strategies in a much more predator tolerant world, the pseudo species barriers that exist among wolves, coyotes, and dogs can break down. Hybridization among these creatures is likely to be a major feature of their continued evolution, a definite feature and not a bug.

These canids  thus make the leap with us into this human dominated age, an age that is experiencing a mass extinction of amphibians and great retrenchment of large sharks and big cats.

Yet they are still there. Evolving as the winds change. Winds that we ourselves are changing and are only now starting to understand.

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Streamer the saluki pursued by Poet the whippet. Streamer is half desert-bred saluki and half tazi from Kazakhstan. He’s a saluki by DNA and by common sense and maybe by the UKC.

Kazakh vs. all england

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The Grounding

streamer on the run

I readily admit that I am an odd human being. A lot of times, my mind is lost in thought and contemplation, and more than a few times, I become transfixed by animals.  I am a hard person to know, because my mind is drawn deeper into those forces than is typical for a member of my species.

I suppose these are the traits of someone who wishes to write about animals, but they are also the traits of an oddball. And I’ve always been an oddball.

I grew up in rural West Virginia, where things were meant to be a certain way, and I never fit the mold very well. I tried to be Christian through my youth and early adulthood, but slowly, I began to realize that I couldn’t be a Christian and be honest with myself.

I came to worship nature, the rocks, the trees, and the animals, and I realized I didn’t need a faith imported Palestine by way of the Roman Empire and the Anglo-Germanic Reformation to understand the world.

Add that problem with the simple fact that my worldview has drifted to the left as I’ve matured, and I now know that I am fully estranged from the land in which I was born. Fundamentalist religion, xenophobia, and fossil fuel worship have generally pushed the people of this forgotten Eastern Outback towards the right.

In so many ways,  I am unmoored, adrift.

But dogs are always going to ground me, though. Their magic is that they exist somewhere between the untouchable animal world and our very contrived civilization.  They are the conduit through which I can be connected to that which is organically evolved and that which is domesticated.

I live with more than a few of them now, a motley crew of German shepherds and sighthounds.

Not one of them is a golden retriever, as odd as that now seems. I have come to the conclusion that my love for that breed comes from my relationship with one individual that was totally atypical for the breed, and she was certainly atypical for what people want to produce in the breed.  People want them to be easier to keep, lower drive creatures with lots of bone.

That golden flame has burned out in my desires. It will still haunt my psyche, but I have finally let it go.

My writings on other wildlife stem from my dog connection. I go to their to closest wild kin, the gray wolf complex and then out to the whole dog family. Then the whole order Carnivora reaches my conscience, and it is but short step before I begin to consider the rest of the Animal Kingdom.

And in short while, I am considering my own station as an insignificant being, a fluttering avatar of carbon in a banal part of the universe. This insignificant being, one with just enough gray matter to question existence, is brought into the deepest humility.

I suppose I do have a religion now.  It is mystical materialism, and my ethics are some form of progressive secular humanism.

And the dogs brought me here. This oddball person who never could fit in a land where conformity is the greatest desideratum now questions in his unmoored existence. But in my unmooring, I am strangely grounded in my own insignificance, as is revealed in the nature of dogs and the rest of nonhumanity.

 

 

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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.

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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.

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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?

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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.

 

 

 

 

 

 

 

 

 

 

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