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Archive for the ‘Extinct animals’ Category

The Extinct Parallel Wolves

Posted in Extinct animals, wild dogs, tagged , , , , on August 12, 2019| 1 Comment »

xenocyon and cynotherium

Depiction of Xenocyon lycaonoides (in the back) with Cynotherium sardous (in the front).

The “hunting dogs” are sister lineage to the true wolves. They were once widespread across Eurasia, Africa, and into North America. Today, the lineage is survived by two species, the dhole (Cuon alpinus) and the African wild dog or painted dog (Lycaon pictus).

But during the Pleistocene, a third species, much larger than two extant species, was ubiquitous. This species, called Xenocyon lycaonoides, was found all over Africa and all over Eurasia.  It ranged into North America, where its remains have been described as Xenocyon texanus.

It was long accepted in paleontology that the dhole and African wild dog derived from Xenocyon lycaonoides, but new evidence that shows the African wild dog deriving from a Pliocene African species called Lycaon sekowei casts that idea into doubt. Further, because the dhole and African wild dog are so closely related to each other, it is doubtful that either derives from Xenocyon.

My take, based upon simple chronology and the genomic analysis of living species, is that Xenocyon and its offshoots were a sister lineage to that which leads to the dhole and African wild dog.

The best way to think of Xenocyon lycaonoides is that it was the gray wolf before there was a gray wolf. It was a pack-hunting canid that was able to expand its range over a wide range. It was roughly the size of a large northern gray wolf, and it would have been a formidable predator of large game.

On islands, though, Xenocyon evolution went a bit weird. On Java, two descendants of Xenocyon lycaonoides evolved. One was Merriam’s dog (Megacyon merriami). It was even larger than the mainland form, but over time, it was replaced by a smaller form that averaged 22 kg (48.5 pounds) called the Trinil dog (Mececyon trinilensis). A new analysis of these Pleistocene canids places both in the genus Xenocyon (which fits a cladistic classification model) and shows that the smaller Trinil dog derived from the larger Merriam’s dog.  Increased competition from tigers and other large predators forced the larger Merriam’s dog to target smaller prey, and over time, they became smaller.

Anothe even more extreme insular form of Xenocyon evolved on the Pleistocene island of Corsica-Sardinia. This island is now two islands in the Mediterranean, but during the Pleistocene, they were connected to each other. On that Pleistocene island, Xenocyon lycaonoides became isolated on an island that was full of small prey, especially a species endemic pika.  This Corsica-Sardinian canid became a specialist in hunting burrowing prey.  It had the ability to thrust its head out laterally better than any living canid, which would have given it an advantage in catching quick-moving prey that would take refuge in burrow.

This species is called the Sardinian dhole (Cynotherium sardous), but it is not directly related to the modern dhole. It was the size of a golden jackal or a small coyote, and it went extinct after humans colonized Corsica-Sardinia at the very end of the Pleistocene. It was the last of the Xenocyon derivatives to go extinct.

The Mosbach wolf (Canis mosbachensis) was a contemporary of the larger Xenocyon lycaonoides.  It was smaller canid that varied in size from an Eastern coyote to an Indian wolf.  It eventually would evolve into the larger gray wolf, which would have a similar evolutionary trajectory to the Xenocyon. It would spread over much of the world. Many regional forms would evolve.

Domestication, of course, would give the gray wolf lots of opportunities for weirdness to come about. Yes, as weird as the so-called Sardinian dhole was, it was never as bizarrely put together as some of our domestic dog breeds.

These extinct “wolves in parallel” do tell us a lot about how a large canid can radiate across the a broad swathe of the planet and adapt to regional conditions and thrive.

 

 

 

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Megalodon sharks died out a million years earlier than we thought and great whites may have been to blame

Posted in Extinct, Extinct animals, tagged , , on February 14, 2019|

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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America’s coursing cougars

Posted in Carnivorans, Extinct, Extinct animals, tagged , , , on December 8, 2018| 2 Comments »

Not so long ago, in terms of the history of our species and certainly not long ago in the history of the world, two “cheetahs” roamed North America, probably running the pronghorn and Odocoileus deer. They were fast and svelte like that cat of Africa and Asia, but they did not make it into the present fauna guild of this continent. 

The great extinction of the megafauna eventually wiped out the dire wolf and these running cats, which were replaced by the gray wolf sweeping down out of Eurasia and from the cougar recolonizing from South America.

Humans probably saw these cats and maybe stole their kills, maybe not though. They were running cats in the era when North America was like frigid Africa, where the faunal guilds of Eurasia and South America ran long and hard into each other. That of Eurasia eventually dominated in the end, but the opossum and the North American porcupine still made it, even though they were part of that austral losing team.

And where there were scores of fake antelope running about with our swift deer, there were two species of coursing cat to put them to flight.  
Miracinonyx was their genus, and M. trumani and M. inexpectus were the two species.  Trumani was more like a cheetah, and inexpectus was more like a very svelte cougar.

For much of my life, these animals were classified as American cheetahs, and there was a whole mythos about cheetahs first evolving in North America. And yes, it’s true that the cheetah’s closest relatives that still live today are the cougar and the jaguarundi, both of which are truly cats of the Americas.

But a few enterprising researchers were able to get some ancient mitochondrial DNA from trumani, and with careful comparison, they found that trumani was most closely related to the cougar. 

So we now think that the cheetah evolved in the Old World from an ancient cougar-like ancestor, but in North America, one form of ancient cougar begat two species with cheetah-like adaptations.

We call this sort of evolution “parallel evolution” in which two descendants evolve similar characters that are not shared by the common ancestor. It is similar to convergent evolution, which is the same sort of evolution without a direct relationship, but in convergent evolution, the common ancestor is so distant that it almost isn’t worth considering, such as the common ancestor of aardvarks and anteaters.

So North America never had any kind of cheetah. What we had instead were “coursing cougars.”

A piece of me longs to have seen one in the flesh, and for a time, cryptozoologists traveled around Mexico looking for such an animal. There were always references to “onzas” in the colonial literature of Mexico, and even today, onza is the term used for a particular cat in the countryside.  Onza means cheetah in Spanish, and there was always a hope that it referred to these old coursing cougars. 

But every lead led to a jaguarundi, which looks like an oddly-colored cheetah-cougar hybrid in miniature, or to really thin specimens of the cougar species.

So the coursing cougars went the way of the Smilodon and the dire wolf and the woolly mammoth.

But when you realize what was here some 12,000 years ago, it’s hard to not to be caught in flights of fancy. Our current wildlife seem picayune by comparison, but we once had all the majesty of the beasts of Africa south of the Sahara.

We’ve lost all these animals during that great extinction, and now we are looming into another one, this one definitely caused by our own actions.

And the cheetahs of Africa hold on by a thread. Those of Asia have almost gone entirely. They exist only in a narrow range in the north of Iran.  There may not be 50 of them left.

Extinction looms. We know it, and yet we feel so paralyzed by its inevitability, we wonder if we can act, if we can change, before it is too late.

To be a running cat is become a true specialist. To be a courser in a world already full of long-distance running dogs is to flirt with near extinction all the time.

But twice this form of cat evolved and ran long and hard across three continents.

Not a bad gamble in the terms of evolution’s blind whims.

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Some assumptions about dire wolves may wrong

Posted in Extinct animals, wild dogs, wolves, tagged , , on August 25, 2018|

dire wolf skeleton

I am not big on popular culture these days. I have not watched one second of Game of Thrones, but I do know that dire wolves have something to do with that series.  I am not into that genre of television. Give me an actual documentary about dire wolves, and I’ll be happy.

But I know that dire wolves are thing from that series only because I do sometimes get asked about them. I don’t know how they are portrayed in that series, but most people think of them as just super large gray wolves that went extinct at the end of the Pleistocene.

The funny thing is that there actually was a super large gray wolf that specialized in hunting large game that also went extinct at the end of the Pleistocene. This animal has been called the Beringian wolf, and although no one has dared to give it a subspecies status, it was essentially a form of gray wolf that hunted megafauna in much the same way that the dire wolf did. The two species were contemporaries, but the Beringian gray wolf did not live in the same parts of North America as the dire wolf, which was found through most of the Lower 48 of the United States and ranged down into northern South America.  This Beringian wolf apparently ranged from Alaska to Wyoming, while the dire wolf was found in mid-latitude North America and ranged south from there.

No one really pays that much attention the Beringian wolf, but it is very likely that everything we know about modern wolves would have applied to that animal. The only difference would be that this wolf was much more specialized in hunting large prey such as bison than modern big-game hunting wolves are.

The same cannot be said for dire wolves.  Dire wolves evolved solely in North America. The general consensus is that it evolved from Armbruster’s wolf, but the exact origin of Armbruster’s wolf is a bit of debate. One well-known hypothesis is that the common ancestor of the modern gray wolf and the Armbruster’s wolf-dire wolf lineage is Canis chihliensis, a Pliocene wolf-like canid. This is the hypothesis suggested by Tedford and Wang, who are leading authorities on North American canid evolution.

However, there is a whole host literature in Eurasian wolves that posits Canis mosbachsensis as the ancestor the modern wolf. This literature, I think, is a bit more robust, for the large numbers of samples of both archaic Canis lupus and Canis mosbachensis show how the wolves of Eurasia went from being small and gracile to larger and more robust over time.

It is possible that this Armbruster’s wolf/dire wolf lineage evolved from an entirely different grouping of the wolf-like canids. It also would place the common ancestor of the dire wolf and modern Canis lupus back millions of years, even to the point where dire wolves were at least as genetically divergent from modern wolves as modern wolves are from African wild dogs.

If that is true, then we cannot make many wild assumptions about dire wolf behavior by comparing them to modern wolves at.  We don’t have any preserved dire wolves in permafrost. They never lived where there are currently big stands of permafrost, so we will never have dire wolf pelts.

Attempts have been made to get DNA from the many Rancho La Brea tarpit dire wolf remains, but they have not been successful. It was found that it was just too difficult to separate the bone from the tar.

So we really don’t know exactly how closely related dire wolves are to modern wolves, but I would be surprised if they turned out to be as closely related to modern wolves as modern wolves are to coyotes.

Indeed, the real problem with all of this is much of Canis taxonomy and systematics is not entirely resolved. The real issue I have now is we have good genome comparison literature that shows a much closer relationship between wolves and coyotes than we previously believed. Much of our understanding of Canis evolution is that we have tended to think of a linear evolution from jackal-like forms to wolf-like form, when the truth of the matter is we have had jackal and wolf-like forms evolve independently of each other within different lineages of the wolf-like canids.

So we are taken aback with the findings that the two endemic African jackals, the black-backed and side-striped jackal, are the two most basal and divergent forms of the wolf-like canid clade, and we are even more taken aback that the dhole and African wild dog are not as distinct from the rest of the clade as these two African jackals. This finding has led to the rise of the genus Lupullela for these two jackals.

In addition, the creatures formerly known as African golden jackals were revealed to be much closer to wolves and coyotes than to the Eurasian golden jackal, which has led to a bit of a taxonomy war on what exactly to call these creatures, though the popular press likes to use the term “African golden wolf,” which was the name suggested in one of the papers documenting their discovery.

None of these discoveries would have been indicated through morphological analysis alone. One would think that black-backed jackals and coyotes were particularly close relatives, for they look and behave pretty similarly to each other. At one time, we would have classified both as primitive or basal Canis.  Today, I think the best description is that the black-backed jackal is a basal Canis, but that the coyote is actually a very derived but diminutive one.

So we have these problems with extant Canis species, and it is very likely that we’re missing the full picture on how dire wolves relate and compare to modern ones.

One thing that should be noted is that dire wolves had very odd bacula.  The baculum is the penis bone that exists in all but a few mammals, and you, if you are a male human being, are among these few mammals without one.

Dire wolves had longer bacula than gray wolves of the same size and they were kinked upward at an odd angle. This bone is probably indicative of a larger penis in a dire wolf than the modern one, and it also might give us some interesting clues about how dire wolves might have behaved.

I have suggested that having this male anatomy might have meant that dire wolves had more competition with sperm penetration than actual male on male conflict during the mating season. We know that within primates, those species that are better endowed tend to be less aggressive with other males of the same species. Those with smaller genitals tend to be more aggressive, and the reason posited for this difference is those with larger genitalia have given up on intermale aggression and the real competition is how far and how much sperm the male can produce.

Maybe something like this was going on with dire wolves. Maybe mating season with dire wolves was just a big ol’ wolf orgy, and the male that could penetrate the female deepest and with the most sperm wound up siring the offspring.

Even calling Canis dirus a “wolf” may not be accurate at all. If it truly is a more distant relative to the gray wolf than we currently assume, then we really need to be careful what we assumptions we are making.

A few years ago, there was a bit of fun speculation on the internet that the dire wolf was actually of South American wild dog clade. A few scholars had toyed with the idea, because there was these two odd species wolfish like canids that were known from the fossil record in South America, called Canis nehringi and Canis gezi. The former was always thought of as being very similar to the dire wolf, and the latter appeared to be somewhat similar to both.

This speculation led to this wonderful image, a depiction of the dire wolf as being an overgrown bush dog.  (The one on the right speculates a South American origin, while the one on the left just turns it into a wolf).

dire wolf bush dog

Of course, serious scholarship performed a phylogenetic analysis of these canids and revealed that Canis nehringi was actually a dire wolf offshoot. Canis gezi was found to be a South American clade wild dog.

So yes, this was a fun bit of speculation, but it’s not much more absurd than assuming that the dire wolf was that fundamentally similar to the modern gray wolf.

We just don’t know. I’m sure that we’ll get a good ancient DNA sample from a dire wolf soon, and we’ll be able to answer some of these questions.

But right now, we need to be very careful in assuming that the dire wolf was just an odd Pleistocene gray wolf.

We’re missing a lot of information, and a lot of the research on dire wolves was performed before we had all these “molecular surprises” with extant Canis species.

There is just so much we don’t know, and it might be a good idea to be careful about making assumptions about dire wolves by comparing them to their supposed modern equivalents.

Those equivalents might not be any more equivalent than those equivalents are to modern African wild dogs and dholes. Yes, there are some similarities, but African wild dogs and dholes are very different from wolves in terms of the exact dynamics of their pack behavior and hunting styles.

So we’re assuming a lot now about dire wolves, but it’s best to wait for me evidence before we play around with speculation. Hollywood will never take this cue, but maybe we should hold back a bit.

We just don’t know.

 

 

 

 

 

 

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The last of them

Posted in Extinct animals, wildlife, tagged , , , , on January 29, 2018| 1 Comment »

bison and calf

The name of the killer has been lost to the annals of history.  All we know is that he killed, and then there were none.

The whole story has been nothing more than a footnote in one forgotten chapter of wildlife in America. What follows is my conjecture about what happened:

The year was 1825. The bison cow and calf wandered down along wide valley.  They were wary beasts, for their kind had been slaughtered relentlessly in these mountains for 50 years.  For the past two decades, the only ones that remained were those that lived in these high mountains and knew how to hide their massive forms in steep hollows when the scent of man crossed their noses.

The pair had been the last survivors of herd that was massacred two weeks before. Buffle hides were demand, and there were mountain men who would oblige the market.

It is easy to blame the hunters for their rapacity, but the resource seemed inexhaustible. In the early days, every one that was shot was soon replaced by another three that came filtering in from west.

And it was that way until these early decades of the republic, when all that remained were these cagey mountain bison that watched every step they took and hid themselves in the deepest redoubts of the Alleghenies.

Two weeks before, a trio of hide hunters stumbled onto the herd in the deep mountains south of where Elkins, West Virginia, now stands.

They wandered the rugged valley that is carved by the Tygart Valley River during the gentle months of spring, when the green grass grew beautiful and sweet.

But that day, the hide hunters came up from the Shenandoah Valley. The older two had trapped beaver the great land of Kentucky before running back to the settled country in the east. They traded in fur and hides, but upon hearing rumors of the last herds of bison in these mountains, they packed up and headed into the Alleghenies, bringing along one of their sons who had been yearning for a bit of adventure.

The hunters spent ten days tracking the herd, and one morning, the son just happened to bump a bull and two cows off a mineral lick. The bison ran deep into a mountain hollow, and when the son tried followed them, he could hear the hoofbeats of many bison deep down in the hollow.

He raced back to tell his father and his father’s partner about the find, and the men loaded up with balls and gun powder and began their approach into the back side of the hollow, where the hillside was steep and the bison would be helpless down below.

There were seven bison down in the hollow. Three cows, two young calves, a subadult bull, and mature bull were nibbling on some forest browse.

The partner was a better shot than the others, so he positioned himself where his shots would fire across the mouth of the hollow. That way, he could shoot sling lead at any bison that tried to leave. The father and son positioned themselves where they could open fire on the whole herd below.

The balls sailed through the air, and in those days before breech-loading rifles, it took many shots to drop five bison.

They fell bloody and dead. The men set to work cutting the hides and then loading their mules for the long trudge back to Staunton and the Great Valley.

A cow and calf ran long out of the hollow and ran and ran until they could no longer hear the gun shots and shouts of men.

For two weeks they roamed is renegades in the mountains, but hunger and the sweet scent of spring grass brought the pair down into the little head of the Tygart’s Valley.

And it was there that an unnamed hunter, perhaps in need of a little meat or yearning for a bit of brass from the buffle hide, slipped down along the laurel that grew thick along the headwaters.  It took six shots to drop the cow, and the cow was down in two.

This hunter had no idea what he had just done. He’d killed a bison or two before in his life, and he knew their numbers were getting scarcer and scarcer in the mountains. But he knew if he waited a few years, another herd or two would mosey back in, and the hide hunting could continue.

But he was wrong.

What no one knew at the time was that this hunter had killed the last two bison in the Original 13 Colonies. And when those two fell, no more herds filtered in from the west. No more hidden bison herds were revealed in some remote hollow or valley.

This animal had carved much of the early infrastructure of what became West Virginia. The bison originally grazed the High Alleghenies in summer then marched west out of the high country when the snows came.  They would travel so far west as to hit the Ohio River, where the winters were milder. They would mosey east every spring to eat the good mountain grasses, and over the years, bovine inertia would carve vast trails coming out of the mountains towards the Ohio.

The indigenous people of these mountains would use these trails as their roads, and European settlers used them too. They would later use big gangs of slaves to clear the trails and turn them into roads that could take a horse or oxcart, and thus, the land was opened for settlement.

Fur trappers took the bison hides and ate the meat.  The homesteaders shot them because they gored horses and torn down split-rail fences.

And soon the bison numbers began to dwindle.

It was the bison the licked the salt from licks in the Kanawha Valley. Hide and market hunters followed them to these big licks, and soon discovered massive deposits of brine. In the years before the Civil War, large numbers of slaves worked the salt works, and these salt works became the basis for the massive chemical industry.

Near the confluence of the Kanawha River and Campbell’s Creek was a massive mineral lick, called the Great Buffalo Lick. It was there that hunters knew to wait for the great beasts and blast them away, and others knew that they could come down collect some salt for the homesteads.

The death of these two bison meant the end for a beast that helped forge so much of what became West Virginia.

No one really talks of bringing back bison, though there are few people who keep them for the novelty meat market.  Large bovines are hard to live with. They are aggressive and dangerous. They spread diseases to cattle, and they gore horses, tear down fences, and run off with brood cows.

They will never roam as wild animals here, and even if they were returned, they would be put on some state management land and then be micromanaged as if they were nothing more than free range cattle.

The bison will never roam this land as wild animals again. They are gone.  And we killed them.

It was a sin made in ignorance, but it was a sin nonetheless.

I sometimes stand in the secondary growth forests that have taken over much of West Virginia when the scores of farm families gave up the land for life in the industrial cities of the Midwest. The forests are thick and thorny. The trails that cut through the hills are carved by white-tailed deer moving through the countryside.  They are narrow trails, where even a short person like myself gets caught on the overhanging limbs and branches.

But I know when the bison were here, the forests were more open. They browsed up high. Their trails were like roads going through the woodland. They also kept big swaths of the land open through their constant grazing.

Land now is kept open only by the mowing machine and the odd stockman who keeps a few head of cows or sheep on some played out pasture.

The forest has all gone to thicket and thorn. It is not the same as it was those centuries before.

It is a land without its big beast, and if you listen carefully, you can hear it mourning.

Yes, it is mourning the passage of the great buffle and the inertia of its hoofbeats and browsing maw.

And so goes the story of the last wild bovine in the Alleghenies, barely a footnote in the annals of history.

But it was so much more.

 

 

 

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What penis bones might tell us about dire wolf behavior

Posted in Extinct animals, wild dogs, wolves, tagged , on December 12, 2016| 1 Comment »

dire-wolf-baculum

Dire wolves are one of those creatures from the past that has captured the public imagination. They are conventionally dreamed of as being massive wolves, and Hollywood has created fictional ones the size of horses.

The truth of the matter is they were only slightly larger than the largest of modern North American wolves.

We know that they were closely related to modern wolves, but their exact position in the wolf family tree is still a bit contested.  The two species are close enough in appearance that it often takes a specialist to figure out whether one is looking at the skeletal remains dire or modern wolf the measurement of the skull features and limb proportions.

One feature, though, that is diagnostic of the dire wolf is its  robust and “perky” baculum.

If you don’t know what a baculum is, that’s because you’re human. In virtually ever other species, the males have a “penis bone” or os penis.  Where I grew up in West Virginia, it was not unusual for men to wear a raccoon’s baculum as talisman of both one’s virility and redneck bona fides.

The dire wolf is one of those ancient animals for which we have a lot of skeletal remains to examine.  In the famous La Brea Tar Pits, where the remains of over a million Pleistocene creatures have been found, dire wolves are the most common species to have been recovered.

The tar pits were a death trap for all sort of large herbivorous mammals, and when they became stuck in the natural asphalt tar, they were easy pickings for scavengers.  Dire wolves came to the tar pits to eat, but many, many of them died. Over 200,000 of them have been taken out of the site.

With such a big sample of dire wolf skeletal remains, paleontologists have been able to figure out quite a bit about their growth patterns, but of particular interest are the bacula of the male dire wolves.  They are shaped not the bacula of any extant canid. They are curved and robust, and when compared to modern wolves of the roughly the same size, they are 44 percent longer.

That is a unusual find, and it suggests something about dire wolf behavior that isn’t true of modern wolves.

Modern wolves generally reproduce through a mated pair. In most wolf packs living in most situations in the wild, only a single pair in a pack gets to mate and produce pups. Other wolves in the pack might mate, but their pups will either be killed or abandoned.

This doesn’t happen every time. If there is abundant prey, these young females are sometimes allowed to raise their pups alongside their mother’s litter.

But in most cases, they don’t get to raise pups.

Modern wolves spend a lot of energy making sure that the mated pair, who are usually parents of the other wolves in the pack, get to mate and get to mate with each other.  The other females in the pack might become pregnant, but they will be attacked if they try to mate with the main breeding male.  The only way they ever get pregnant is by wandering interlopers who haven’t yet formed a pair bond with a female.

During the mating season is when young wolves typically leave their parents’ pack.  They typically don’t have any mating opportunities, and the constant bickering wears on them.

The big and strangely shaped bacula of dire wolves suggests they might not have been quite like modern wolves.  These bacula are suggestive that dire wolves were “better endowed” than modern wolves, and larger genitalia is usually associated with a less physically competitive reproductive strategy.

This phenomenon is well-known in primates. Generally, if a monkey or ape has bigger testes or penis, there is going to be less physical confrontation when it comes to mating.

The competition for well-endowed monkeys is how much semen a male can produce and how far up in the female he can penetrate it. If you can produce more semen and get it deeper into the female’s reproductive tract, then you’re more likely to pass on your genes.

In less-endowed species, there is much more physical confrontation to get one’s genes passed on.

My guess is that this applied to dire wolves. They may not have even had a proper pair-bonding system, and a dire wolf bitch may have mated with many partners in much the same way female domestic dogs do.  The male dire wolves may have had very little competition for mating. They just mated and got along with each other.

It would have been an asset in a dire wolf pack for males to have gotten along with each other. More peace in a dire wolf pack means that more wolves remain in the pack for a longer period of time, and that means they would have had larger packs that would have been much more capable at hunting large prey. They also would have been better able to run off short-faced bears from their kills and to compete with Smilodons and American lions.

It’s likely that the intense competition between huge carnivorans during the dire wolf’s reign forced them into a more cooperative breeding and pack structure.

Again, no scientist has ever seen a dire wolf or observed their pack behavior, but they had this weird adaptation that sort of points to a more peaceful pack existence than exists in the modern species.

My guess is that dire wolves traveled in massive swarms, much like those seen in dholes of today. They were ruthless scavengers and dogged hunters.

When mating tame came, they bred like village dogs. Males would bunch up around a bitch in heat and each would mate with her. There would be no pair bond between the male and female.

The competition was in the semen and the implantation thereof.

 

 

 

 

 

 

 

 

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North Carolina’s game commission wants the red wolf program ended

Posted in Extinct animals, Uncategorized, wild dogs, wolves, tagged , on February 5, 2015| 14 Comments »

KONICA MINOLTA DIGITAL CAMERA

As long-time readers know, I am a bit of a skeptic when it comes to the taxonomic validity of the red wolf.  This is particularly true when the only genome-wide analysis of wolves and coyotes in North America revealed that the creatures being conserved as red wolves were actually coyote/wolf hybrids that actually have only slightly more wolf ancestry than a typical Eastern coyote.

That said, there are a lot of individuals who have devoted a lot of time and energy and entire careers on red wolf conservation, but I knew that when that study came out, it would be just a matter of time before the politics of red wolf conservation would come to a head. After all,  North Carolina has just recently begun to have issues with Eastern coyotes, and although most of the coyotes in North Carolina are on the smaller side, it would be wrong to assume that there were no coyotes in North Carolina with wolf ancestry.  And it’s possible, considering that coyotes with wolf ancestry have been found as far south as Virginia.

Coyotes are pretty much blamed for everything that goes wrong in conservation biology in the East.  If deer hunters don’t bag a huge rack of antlers, then it’s obvious that the coyotes are killing them all. The more nuanced explanation is that coyotes do take quite a few fawns every year, but unless there is a heavy snow (which doesn’t happen in Eastern North Carolina), then it’s very unlikely that the coyotes are killing all the adult deer. Fawn recruitment is an issue, so a lot of game managers, especially in the South, do coyote controls. Coyote controls involve trapping, hunting them with foxhounds, and night hunting.

And it’s this night hunting of coyotes that caused the problem with the red wolf in North Carolina.  Night hunting involves going out at night with an electronic call and an amber light (just to show everyone you’re not spot-lighting deer), and then using those calls, which produce howls and prey in distress sounds, to lure a coyote or two  to its demise. Some people are adept howlers, and you can even buy coyote calls that produce different howls and prey in distress calls for that purpose.

Coyotes can be called in the day time, but if they live where there is significant hunting pressure, they tend to stay holed up in the brush until night falls.

Of course, most of the coyote hunters who do this sort of thing got into it to protect deer and other game numbers, and what usually happens is they find the coyote a much more challenging game species than any of the more typical game. Predator hunting becomes an obsession, a deep burning passion.  Some of these predator hunters actually want to protect coyotes from excessive hunting, just so they will have more coyotes to hunt.

And this is where red wolf recovery went south.

In the five counties where red wolves roam, there has been a long legal battle over whether coyotes can be hunted in red wolf range. In May 2014, a court-ordered injunction banned coyote hunting in those five counties, but by November, the N.C. Wildlife Resources Commission created a framework that would allow some limited coyote hunting in the area.  Also, if one is legally hunting coyotes, one can kill a red wolf if it is taken by accident. I should note that red wolves look a lot like Eastern coyotes. They are the same color, but they are usually somewhat larger than the coyotes typically found in North Carolina. However, I can tell you that if red wolves were released here in West Virginia, you would never be able to keep them straight. We actually do have coyotes that approach red wolf size, which kind of makes sense. After all, the coyotes of the Northeast and the Mid-Atlantic are essentially the same thing as red wolves– coyotes with some wolf ancestry.

You would think that this rule alone would be enough to get red wolf conservationists screaming, but what came next is something akin to a neutron bomb going off in the red wolf community.

Last week, the North Carolina Wildlife Resources commission issued two resolutions to the US Fish and Wildlife Service. The first resolution declared that because the extant red wolves in North Carolina were so heavily derived from coyote stock that there were no more pure red wolves left and that the species was extinct in the wild as of 1980– which, means that the red wolf recovery program would end under the Endangered Species Act. Once a species is declared extinct, it gets removed from the Endangered Species List, and all recovery efforts are ended.

The second resolution calls for a removal of red wolves from private property.

In the 90’s and the first decade of this century,  the red wolf recovery program in North Carolina was celebrated as a successful wolf reintroduction in the East. These wolves lived in area where most confined livestock and poultry operations and crops comprised the main agricultural concerns. Very few opportunities existed for red wolves to cause problems with people.

But now that coyote hunting is gaining in popularity in the state, the red wolves finally hit snag. Of course, the Fish and Wildlife Service could only maintain the supposed purity of the red wolves running loose in North Carolina though an intense trapping program.  The population of canids called red wolves today derive from only 14 individuals, and as we know that most wild canids have a strong inbreeding avoidance instinct, red wolves will readily cross with coyotes. After all, red wolves are mostly coyote in ancestry, and those 14 were all derived from a population of coyotes and wolves that were running together in Louisiana and East Texas. In Peter Steinhart’s The Company of Wolves, the author recounts a government trapper in Louisiana who kept encountering litters of coyotes, where one pup would mature at 75 pounds, while another would top out at 25. This strongly suggests that the red wolf that exists now was a hybrid.  There were some rather primitive genetic tests done on these wolves, but these were quite unlike the vonHoldt paper.

What likely happened was that as wolves in Texas and Louisiana became rarer, they began to mate with coyotes. Because this wolf held on longer than in other parts of the South,  there were more hybrids with wolf-like features that were then declared a species. There was some dodgy paleontology work that connected these wolves with primitive wolf-like canids from North America. They found some unique biochemical and molecular evidence in the 14 wolves, and based on the dodgy paleontology, the primitive biochemical and molecular evidence, and the phenotype, they declared these animals to be a species.

I haven’t seen anything that any researcher has produced that falsifies the vonHoldt paper, which is the most extensive analysis of wolf and coyote genomes performed to date.

Now, I am a big supporter of the Endangered Species Act. I am also a supporter of wolf recovery programs, but I’ve come to think that this particular program is quite problematic.

The taxonomic value of the creatures we are currently calling red wolves is dubious at best. I’m open to some good evidence that contradicts the genome-wide study I linked to earlier, but I haven’t seen it. All I’ve seen is a critique of that study, which basically says you can’t use SNP’s to determine evolutionary relationships, but SNP’s look at much more of the genome than microsatellite clustering and mitochondrial DNA do– which all that the red wolf researchers have.

Also the big critique on the red wolves are hybrids study I’ve seen is they didn’t sample enough red wolves. The problem with that argument is when a population derives from only 14 individuals, you really don’t need a huge sample to get an idea of what they are.

This is one of those cases where I think the best science is on the side of delisting the red wolf.

And let’s worry about Mexican wolves.

Or maybe the diamond darter, a tiny fish that is now only found in the Elk River drainage of West Virginia.

But that’s just a little fish, living in a state where economic interests that generally oppose clean water have long held sway over the political process.

It’s not some ancient American wolf, which at one time was declared the root-stock of all wolves and coyotes.

Wolves are great symbols of conservation.  If left alone, they do recolonize their former range and often thrive. They are also closely related to domestic dogs. Indeed, dogs are derived from some Old World form of Canis lupus, and to the popular imagination, killing a wolf is like killing beloved pet dog. The wolf became sort of a “Fido as a Noble Savage,” which in itself is a pretty bad place for animal to be.

So because this symbolism that having hard discussions about wolves is difficult.

Protecting endangered species is more than raising hell whenever charismatic species might be threatened. It about preserving ecosystems and habitat, as well as all the unsexy little creatures, ones that will only gets nerds like me excited.

I would hate for this red wolf fiasco to set a precedent that state wildlife agencies can just complain to the US Fish and Wildlife Service whenever a particular endangered species is causing them problems. The Western states have even more endangered species that are conflicting with state interests. For example, it was recently determined that the sage grouse of southeastern Utah and southwestern Colorado are a unique species, and what’s more, it’s actually an endangered species. In November of 2014, it was decided that this species of grouse, called the Gunnison grouse requires Endangered Species Act protections. The state of Colorado just sued Fish and Wildlife Service over the listing. Now, it’s unlikely that these grouse are going to be delisted because Colorado complained about them, but depending upon how the courts interpret the law, it could get interesting.

Red wolves are just a bad case all around.

The lesson to conservationists ought to be that if you want to save a species, you better make sure that there are no huge, gaping questions about its taxonomic status.

I think the sad story here is that we’ve lost the Southern wolf, replacing it with wolves with a high amount of coyote ancestry, does not change this fact.

The Southern wolf is mentioned in the literature throughout region, and it was almost universally described as melanistic.

Here is photo taken by an early camera trap in Louisiana by Tappan Gregory in 1935.  It shows a black wolf with a larger head, broader muzzle, and smaller ears than what one finds in the modern “red wolf.”  (The current “red wolf” subspecies is call Canis rufus gregoryi, after Tappan Gregory.)

southern black wolf

Hat-tip to Sheila Collins for finding this photo.

That wolf is gone. Perhaps it lives on the wolf genes of the modern hybrid red wolf, just as the Northeastern timber wolf (Canis lupus lycaon) lives on the “coywolves” the Mid-Atlantic and the Northeast.

The thing about wolves, though, is they are coming back. Bit by bit.  Some wolves have incorporated coyote blood, as is the case with the Algonquin Park wolves, and this hybridization even occurred before Western man arrived in this continent. The vonHoldt paper on wolf and coyote genomes showed that Great Lakes wolves hybridized with coyotes at some point 600-900 years ago.

That means that wolves and coyotes, like modern humans and Neanderthals and Denisovans, exchanged genes with each other. Our popular understanding of evolution is that a species origination is one monophyletic population becoming genetically distinct and then losing chemical interfertility with the ancestral population and the sister taxa. However, evolution also has sister taxa exchanging genes a lot more often than we generally assumed. Wolf and coyote hybridization in North America has actually been underestimated as a driving force for the evolution for both species. We know that wolf genes have given Eastern coyotes an advantage when it comes to hunting deer and has likely enhanced their spread into the white-tail woods.

When wolves came into this continent from Eurasia, they came into land full of coyotes.  It is possible that they exchanged genes then, but there is no record for it.  Or maybe those early hybrid populations became extinct.

What we do know that is that hybridization occurred without the influence of Western Civilization and its attendant philosophy of wolf persecution, and in the case of some wolf populations, coyote genes could be a source of genetic rescue.

So the wolf that will come back won’t be exactly like the one that was extirpated. It will have genes from coyotes and probably domestic dogs.

And we should just accept it. After all, no one says that we should kill all the black wolves, even though that black coloration came from crossing with domestic dogs.

The wolf that comes back will be in a world where there aren’t as many elk or moose to hunt, but there will be plenty of white-tailed deer and raccoons. This wolf will have to be adapted to hunting this quarry, and it will have to be as wary as a the most paranoid of coyotes in order to survive in this new New World.

This is the approach that should have been used to restore wolves to the Lower 48. It avoids all the crazy debates about taxonomy, and it recognizes that ecosystems have been changed profoundly since 1492.

So if North Carolina succeeds in ending the red wolf program, maybe it will be a chance to go forward towards a twenty-first century wolf conservation ethic.

That’s certainly what would be best for the wolves, for wolves have to fit into our world now. They can do it, but we can’t get them there if we hold onto old ways of thinking.

 

 

 

 

 

 

 

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Why did you rob me?

Posted in Extinct, Extinct animals, tagged , on September 8, 2013| 15 Comments »

Keulemans great auk

I have had discussions with people who don’t think that extinction of species is as big a deal as conservationists want to make out.

Mass extinctions are not uncommon in the history of the earth. We just happen to be living at the time a mass extinction. No harm. No foul.

But really it’s no fowl.

I think the most profound question about extinction is one I often hear politicians make about national debt or the strength of social insurance programs:  Surely you don’t want to leave behind that much debt for our children?  Surely you want social security to be around for future generations?

The concept of “generational theft” can also be brought to bear on the question of extinction.

There are many animals that I’ve never seen alive.

I came to late to see a sea mink slinking along a rocky Maine shore, and I came too late to see the skies blacken with passenger pigeons and Eskimo curlews. I will never be able to visit the Falklands and see that unique island wolf that once roamed its beaches, and I will never know what it’s like to hear the Carolina parakeets, the great North American conure, flit through the forests of West Virginia.

These animals have all been robbed from me by the previous generations.

But I cannot go back in time and tell them to stop the madness. They were merely operating within the cultural frameworks of their time. Nature’s bounty appeared to be limitless, and then came the fall.

Even the scientists of the day weren’t aware of what they were doing.

A case in point is the great auk, a giant flightless sea bird that was native to the North Atlantic. It swam and dived much like the penguins of the southern oceans, but it was more agile than a penguin in the water.

The great auk was in the family of sea birds that includes the puffins, the murres, and guillemots. All living birds in the family can fly, but the great auk could not.  As a result, the great auk was forced to nest on remote islands with sloping approaches to the sea. All the other birds in the family could fly into jagged rocks that protruded from the sea, but the great auk was greatly handicapped in this regard.

To make matters worse, there were only a finite number of such islands in the whole North Atlantic, and each summer, they would become jammed with throngs of giant black-and-white birds.

Sailors on fishing and whaling ships were quick to notice  the boon that came from fat birds laying nice, plump eggs on easily accessed islands. Not only could they kill the birds and eat them, they could also collect their eggs. And if a whaling ship needed a bit more oil to top off its stores, it could render down some auks into oil. Fishermen used the meat for bait, and down collectors found its down a good substitute for eider.

In the early nineteenth century, its population crashed, and every naturalist worth his salt demanded eggs and skins of adults for taxidermy.  There was a rush to kill as many auks as possible and to collect as many eggs. Every gentleman naturalist wanted specimens and eggs for study, and the fishermen and whalers were happy to provide them.

It was in this madness that the last of the great auks were killed on the island of Eldey off the coast of Iceland. The extinction of the great auk happened when three Icelandic fishermen came across a pair of the auks tending to their single egg.   Two men killed the adults, and the third man, perhaps angry that there were only two birds to be had, smashed their egg with his boot.

This attack happened on July 3, 1844, and that date is rather unique. It is one of the few times we know the very second of an extinction. Those auks were the last two birds of their kind, and they were killed in the name of scientific curiosity.

This story has been dramatized in so many books that it’s almost reached legendary status.

It’s because this is one of the few times we know exactly when the generational theft was complete.

Reading account after account of how numerous great auks were in the North Atlantic, my imagination is piqued.

What would have been like to see the great assemblages of auks on their islands?

It’s something I will never see. It’s something that I can only read about in books and conjure up in the back of my mind.

A piece of me is angry that the great auk was allowed to go extinct in this fashion, but it is that anger that I realize a simply moral truism.

What if someday, future generations look back on us and wonder why we didn’t do enough to stop the tiger or the cheetah from becoming extinct?

Extinction for both of these cats is a very real possibility, and if they do go, we will be as much robbers as the men who took the lives of the last auks.

Knowing what we know now, don’t we at least owe it to future generations to try to preserve a bit.

Is that too much to ask?

Or are we so consumed with ourselves that we can’t try  to save a bit?

The answer to that question is the one that will show us who we were to the historians of the future.

Were we able to hold forth on our engines of progress just a bit to allow a few truly remarkable wild things survive?

Or were we took caught up in the desire to subdue it all?

We are never going to return to the mythic age before man. Many anti-conservationists scoff at the strawman that claims that all conservationist want to do is destroy civilization and return it back to the days when all things were wild and untouched.

So long as humans exist on the planet, that goal can never be achieved, and all conservationists know this.

But just because we cannot return to the true ecological Garden of Eden doesn’t mean we can’t try to preserve what we can.

To refuse to do otherwise is to be comfortable with a terrible kind of generational theft.

I certainly am not.

 

 

 

 

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Sea lizard

Posted in Extinct, Extinct animals, wildlife, tagged , , , on December 21, 2012| 3 Comments »

Platecarpus

When I was a boy, I used to catch eastern fence lizards and five-line skinks. I never knew the proper name of the former species.

In West Virginia, they are always called “hell hogs,” which, in my estimation, is far cooler name than “eastern fence lizard.”

The fence lizards are in the suborder Iguania, and they superficially resemble their distant iguana cousins. They even do that head bobbing behavior that iguanas do.

I was always fascinated by iguanas. They were like giant hell hogs, and when I learned that there were iguanas on the Galapagos Islands that actually went into the sea to eat algae, I was utterly amazed.

These were real sea lizards!

What I didn’t know at the time is that the marine iguanas weren’t the first lizards to go into the sea.

The truth is that millions of years ago, there were lizards that were adapted to an entirely marine existence.

As a kid, I didn’t know this.

I thought that dinosaurs actually were large lizards, and all my toy dinosaurs had legs that bowed out like those of a monitor lizard.

One of the sad things about the popular conception of dinosaurs is that we think that name, which means “terrible lizard,” actually means that these animals were lizards.

The truth is that all dinosaurs are more closely related to birds than they are to the little fence lizards of my youth. Some dinosaurs are even closer to birds than that, and now, if we are to classify them systematically, we have to consider birds a subset of dinosaurs. Their technical name is “avian theropod dinosaurs.”

I was somewhat crestfallen when I found this out.

That meant that the only amazing lizards were marine iguanas and my other favorite species, the komodo dragon.

What I didn’t know is that there were actually lizards that were every bit as amazing as any dinosaurs.

And you have to forgive my ignorance here.

I actually didn’t know about the marine lizards known as mosasaurs until about three or four years ago.

When I found out that these truly marine lizards existed, I was elated.

The animal depicted above is Platecarpus. It was a highly derive mosasaur that was once common in the Western Interior Seaway that divided North America into two land masses during the Late Cretaceous.

There is a strong suggestion that its tail bent down and a caudal fin was attached to the bend to make a shark-like tail.

And it was basically a 14-foot shark lizard that lived around 80-85 million years ago. A recent study revealed that it even swam much like a shark, which means it would have been one of the fiercest predators in the seas of its time.

Mosasaurs evolved from an archaic varanoid lizards called aigialosaurids, but this is, of course, hotly contested. Aigialosaurids looked an awful lot like modern monitor lizards, and it has been the recent fashion to count mosasaurs as varanoids. Currently, there is a lot of debate over what’s a varanoid. Some authorities count snakes as a type of highly derived varanoid, and if we count snakes as lizards, then sea snakes are also marine lizards.

But there isn’t a sea snake that is anything like a shark.

Evolution is one of the most amazing facts I’ve come to understand.

When I was a kid, my grandmother would keep little chicks from her laying hens in boxes next to her wood-burning stove. In the early spring, the hens would sometimes get too far ahead of themselves and lay eggs before the spring frosts topped, and very often, the chicks would be exposed to the elements and would die. My grandmother always brought those early spring chicks in, and they would be kept warm by the fire.

I didn’t know that these fragile little fuzzballs were actually more closely related to the Tyrannosaurus than they were to anything else living on the planet at the time.

And I didn’t know that the little lizards I used to hold in my hands and put in mason jars and homemade enclosures once were related to beasts that once rivaled sharks in the ancient seas.

Evolution is one of the most amazing facts you’ll ever understand,.

It will humble you, and it will make you look at the natural world in ways that you never thought possible.

That’s why I want people to understand it.

When I found out exactly what it was about, it was one of the most liberating experiences of my life.

And it really stimulated my imagination.

I know that I won’t look at a common fence lizard without the idea of a mosasaur coming up in the back of my mind.

I will marvel at that little lizard.

Not a mosasaur.

But a cousin of sorts.

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The last mammoths were not inbred

Posted in Extinct animals, tagged , , on March 30, 2012| 1 Comment »

From UPI’s Science News:

A British study on the extinction of woolly mammoths found the last known population of the prehistoric animals did not die out because of inbreeding.

The study, conducted jointly by British and Swedish scientists, examined bones, teeth and tusks from Wrangel Island in the Arctic Ocean where the last known population of woolly mammoths lived about 4,000 years ago, the BBC reported.

Mammoths generally disappeared from mainland Eurasia and North America about 10,000 years ago, but lived on for another 6,000 years on Wrangel Island.

“Wrangel Island is not that big and it was initially thought that such a small population could have suffered problems of inbreeding and a lack of genetic diversity,” said the report’s co-author, Dr. Love Dalen of the department of molecular systematics at the Swedish Museum of Natural History.

Researchers found that, contrary to popular belief, the animals more likely were killed off by human activity or environmental factors.

The report, published Friday, concluded that the extinction of mammoths on Wrangel Island was “not a delayed outcome of an inevitable process” such as inbreeding.

“This suggests that the final extinction was caused by a rapid change in the mammoths’ environment, such as the arrival of humans or a change in climate, rather than a gradual decline in population size,” the study said.

The study also found the population of mammoths on the island generally ranged between 500 and 1,000.

Dalen said the study can be useful in modern-day conservation programs.

“What’s really interesting is that maintaining 500 effective individuals is a very common target in conservation programs,” he said. “Our results therefore support the idea that such an effective population size is enough to maintain genetic diversity for thousands of years. These mammoths did fine with what was originally considered to be a small number.

One should note that most dog breeds have far fewer than 500 effective individuals in their populations.

That should be a cause for concern, but one should realize that there are other measures of genetic diversity that need to be considered when making these conclusions.

Many people are not aware that mammoths actually did live into historic times, although in that part of the world written records from that time period are probably nonexistent.

But they were there.

And they were thriving.

Because their extinction is so late in time, it is possible that hunting pressure could have caused the extinction. However, there is no evidence that humans ever hunted these mammoths, so the most likely reason for their extinction is climate change.

There is a lot of debate about what cause the extinction of mammoths on mainland Eurasia and North America. Human overkill and climate change have been bandied about for decades.  And a third possibility, a combination of climate change and human hunting pressures, seems to be the current best-supported hypothesis. The mainland extinction was part of a much larger megafaunal extinction that happened at the end of the Pleistocene.

Of course, now we have mad scientists in Russia and South Korea who are going to clone a mammoth.  (But this project is much more difficult than one might realize).

But these cloned animals will always be  gimmick.

They will never be a self-sustaining population.

But it wasn’t that long ago that there was a healthy, genetically diverse, and sustainable population of mammoths.

Of course, on i09’s article on this same study, we have the obligatory creationist analysis in the comments section:

What’s even more mind-boggling is.. The Earth was completely different before the Great Flood with lots of creatures and animals that people in the world today either deny existed or refuse to believe could have existed.

They never give up, do they?

 

 

 

 

 

 

 

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