The Dire Wolf

When I awoke, the dire wolf

Six hundred pounds of sin

Was grinning at my window

All I said was “come on in,”

“Don’t murder me . . .”

– Robert Hunter & Jerry Garcia

In recent years, the Dire wolf – or the idea of a “Dire” wolf – has become fairly popular.  It’s not just the Grateful Dead song.  It’s part of popular culture in Game of Thrones.  The dread, cunning, rapacious, vicious, enormous Dire Wolf.

The Dire wolf was North America’s own.  Scientists think that it, unlike the gray wolf, evolved on this continent.  And what a wolf it was.

It was big, weighing up to 175 lbs.[1] And strong –  very strong.  Its jaw was larger than that of modern wolves, and it teeth were bigger, and its bite was stronger.  It was well designed for hunting and killing and then eating large prey.

Its scientific name, canis dirus incorporates the word  – dire.  From the Latin meaning “fearful” or “awful.”  Nice.OLYMPUS DIGITAL CAMERA

Like modern wolves it was able to  adapt to all kinds of environments.   Its remains have been found throughout the country, and into South America as well.  It lived in all sorts of habitats – forests, mountains, open grasslands and plains; from sea level to over a mile high. And it was very common. Over 3,600 of them have been pulled from the La Brea tar pits in Los Angeles.

The Dire Wolf was carnivorous.  Scientific analysis shows that its diet favored bison and horses, although it ate mammoths, sloths, and other large prey, if it could catch them.  It was heavily built, and while only slightly larger than modern gray wolves, it weighed probably 25% more.  And, as noted above its skull contained adaptations that suited it for hunting large, heavy prey – its skull was broader than that of modern wolves, and had attachments suggesting that the muscles which drove its jaw were exceptionally powerful.

So far, only bones have been found.  We don’t know what its fur looked like, but everyone sort of assumes that it looked like modern wolves.  So how did it compare to modern wolves?

wolf

Well, as noted above, its skull was bigger, heavier and stronger – more suited to hunting and grabbing onto large prey animals. But its braincase was smaller.  I’m not sure that intelligence had to do with anything in this context, though.  Both dire wolves and gray were very successful for tens of thousands of years, so while a gray wolf might score higher on an IQ test than a dire wolf, it doesn’t seem to have made any actual practical difference.

Its legs were shorter and stockier than modern wolves, suggesting that it wasn’t as fast, and not as well suited to the long effortless loping that wolves do.  These anatomical differences, combined with the fact that the dire wolf evolved in North America, while the gray wolf evolved in Eurasia, raise questions about how the dire wolf lived.  Modern wolves are pack hunters – Was the dire wolf?  There is no evidence of sexual dimorphism – the females were the same size as the males, so presumably they engaged in the same behaviors.  But was this the active pursuit of, say, a bison?  Or were they more like hyenas, and scavengers, first, and hunters only secondarily?   Skeletal evidence shows several things that shed some light on its behavior.

First many of these animals survived broken bones.  This implies that perhaps the pack brought food to injured members.  And it suggests that there was some level of pack behavior.

This is supported by scarring on some of the skulls consistent with hierarchical behavior –  dominant wolves grabbing and biting the heads and faces of subordinate animals.

Finally, the dearth of wolf puppy bones found at La Brea also supports the idea that these were packs animals.  They probably left the puppies back at the den while the pack was hunting, and then brought food back to the puppies.

But while it is reasonable to suppose that they were pack animals, the size of a typical pack is unknown.  Were they small, family-based packs like coyotes, (to whom they are closely related)?  Or did they run in larger, bigger packs, better suited to hunting and bringing down large prey?

The gray wolf came over, across the Bering Strait land bridge, from Eurasia, approximately three hundred thousand years ago, and found the dire wolf already here.  And they coexisted for hundreds of  thousands of years.  Presumably, then they filled different ecological niches.  The gray wolf was, it is thought, faster, more fleet of foot, and probably able to run for a longer time than the stouter, stockier dire wolf.  The dire wolf, in turn had a skull better equipped for taking large heavy prey.  So, presumably, the gray wolf hunted smaller faster animals – deer, or elk – while the dire wolf was taking horses and bison.  Or, as some believe, perhaps the dire wolves scavenged.  That would have been quite a sight – a Smilodon, having taken down a camel, or horse, looks up, and sees fifteen or twenty wolves coming in, focused, intent, snarling, ready to take the kill.

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As with so many other large animals, the Dire wolf went extinct some ten to twelve thousand years ago.  But the gray wolf did not.  This is a real mystery.  Why the one, and not the other?

There are several theories.  One is that the dire wolf was so adapted to large prey that when the megafauna went extinct, it did too, while the gray wolf was more adapted to smaller prey which survived.  Some have speculated that the dire wolf didn’t so much coexist with the gray wolf as compete with it, and the gray wolf finally won.  Another theory is that the dire wolf became extinct in the face of a new competitor – human beings.

But there are problems with each of these theories – over-specialization; competition with gray wolves, pressure from humans.

First, dire wolves were, according to the fossil remains, very common.  And spread throughout the continent.  As were gray wolves.  If it was pressure from humans, then why would dire wolves become extinct and gray wolves survive?

Dietary analysis shows that dire wolves’ diet differed from that of gray wolves – so they weren’t directly competitors.  Although, once the large slow animals were gone, the gray wolf would probably out-competed the dire wolf for hunting the smaller fast prey – deer and elk – that remained.  But – and it’s a real question – the bison remained.   So why didn’t the dire wolf continue as it had, hunting the buffalo, and thriving?

I think it is reasonable to posit this theory:  The dire wolves were primarily scavengers, although certainly capable of hunting when necessary.  Remember that this was all completely wild country.  In historic times mountain men and other early explorers of the west reported that hundreds and hundreds of buffalo would be killed trying to cross a river (much as still happens in some part of Africa, today, with wildebeest).  So, at times, at least, there would have been ample food for the wolves to scavenge: hundreds of horses, or some mammoths, say, killed trying to cross a river.  And if they roamed in large packs, they were formidable, certainly able to drive a pack of lions from a kill (again, analogous to hyena-lion interactions in Africa, today).

But they were, therefore, specialists.  Not generalists, like the gray wolf.  The gray wolf will hunt and eat deer and elk, but also – mice.  Anything it can get.  And perhaps, notwithstanding what I wrote up above, maybe intelligence does play a role, here; letting the gray wolf see and understand and seize new possibilities, that the dire wolf didn’t.  Then, when whatever happened to wipe out so many of the large prey animals, the dire wolf was ill-suited to adapt.

The answer is elusive and, as yet, unknown.  Each species in an ecosystem is filling a niche so sensitively, and the entire system is so finely tuned, that any little change may throw it out of balance.  In the case of the dire wolf, it may be that there was no single overwhelming explanation for their extinction, but a combination of small factors, which, taken together, pushed it out of its niche, and into extinction.  So, the horse, which has made up a substantial part of its diet, goes extinct.  The pressure on the dire wolves goes up.  Human hunters replace lions and Smilodon, and unlike them, can’t be driven from the kill – and the pressure goes up.  And the humans make more efficient use of the animals they’ve hunted, leaving less for the wolves to scavenge.  And the pressure rises.  Not so much a single extinction event, perhaps, but something more akin to the death of a thousand cuts.

But even though the actual wolf is gone, the DIRE WOLF lives on in song and story.  And for now, that will have to do.

Useful links:

http://library.sandiegozoo.org/factsheets/_extinct/direwolf/direwolf.htm

http://en.wikipedia.org/wiki/Dire_wolf

Craniofacial morphology and feeding behavior in Canis dirus, the extinct Pleistocene dire wolf, W. Anyonge, A. Baker, http://onlinelibrary.wiley.com/doi/10.1111/j.1469-7998.2006.00043.x/abstract;jsessionid=69EBE865899AA29760D72BCFF14A3E3E.f02t02 (only the abstract is available online).

http://exhibits.museum.state.il.us/exhibits/larson/canis.html

http://onlinelibrary.wiley.com/doi/10.1111/j.1469-7998.2006.00043.x/abstract;jsessionid=69EBE865899AA29760D72BCFF14A3E3E.f02t02 (only the abstract is available online).

http://the-wolfs.webs.com/prehistoricwolf.htm.


[1] Not six hundred pounds.  Not even close.  Sorry, Jerry.  Sorry, Deadheads.

The American Lion

 

Once there were lions.  Once lions roamed this country.  Here, where we are, lions hunted, and ate, mated, drowsed through the long afternoons, roared as the moon rose.  Lions.

Specifically, the now-extinct American Lion (panthera leo atrox).

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There has some controversy about the taxonomy of the American Lion;  about just where it fits in; about its relationship to modern lions, tigers, and other big cats.  For a while, it was thought that it might have been more closely related to the jaguar, but now, the prevalent view is that it is most closely related to the lion of today, and to the now extinct European cave lion (panthera leo spelaea).

So we are talking about real lions.  Only bigger.  Like so many of the animals back then, twelve, fifteen thousand years ago, the American lion was bigger than its modern counterpart.  20 -25% bigger.   It might have weighed as much as seven hundred pounds, and been seven feet long – excluding its tail.  Its legs were proportionally longer, and its bite was considerably stronger than modern lions.

That is one hell of a predator.

But it wasn’t the only apex predator roaming around back then.  In North America, there were four top predators, all at the same time:  The great short-faced bear; Smilodon; Dire Wolves, and the American Lion.  In modern Africa, lions and hyenas are competitors and adversaries.  But here, there were not only two teams of rivals, but four.

So how, exactly did that work?  Were they competitors, chasing the same game?  They certainly could have been – each was fully capable of taking down a horse, or bison, a camel, an elk.  Or did they preferentially take different animals?  The Lion taking horses, for example, while Smilodon took bison.  And what if they met?

If the American Lion was close kin to the modern lion (as seems likely), then we can suppose that its behavior was similar too.  So it probably hunted in prides; males probably fought each other for access to females.

The La Brea tar pits have produced incredible amounts of animal fossils – lots and lots of dire wolves; many Smilodon.  But not too many lions.   And most of them were males.

Why?  Perhaps lions were too intelligent to be drawn into danger (the sticky asphalt morass) by the cries of entrapped prey animals.  Perhaps only solitary males were hungry enough, desperate enough to venture in.  Maybe lions were simply rare.

And yet, their remains have been found nationwide.  There really were lions roaming here.

In historic times, there were enormous herds of buffalo (which, yes, I know should be called bison). There were (and are) elk, and deer.  Those would be suitable prey for any of them – The great short-faced bear; Smilodon; Dire Wolves, and the American Lion.

So what the hell happened?  Why did the American Lion, like the others, go extinct?

Climate change?  Hunting pressure by humans moving into the Continent?  Some disease?

A couple studies have shown that the animals appeared to be well-fed – i.e. not starving, just before they became extinct.  So, the mystery remains:

Once lions walked and stalked here, and now they are gone.

Here’s a link to an informative site:  http://library.sandiegozoo.org/factsheets/_extinct/lion_american/lion_american.htm*** 

Here are two short excerpts from my novel, dealing with American Lions:

 

I don’t know what the hell happened.  Maybe Devereaux was unbelievably passive-aggressive.  Maybe he didn’t give a fuck.  Maybe he fell asleep.  It was his second watch of the night, anyway.

 I was in my tent, tossing, trying to get to sleep.  Kinda half-awake.  And I heard the horses snorting, stamping, whinnying.  Devereaux yelling ‘Hey!  Hey!’ Then, two quick shots.

Snarling.

“Hey! Dammit!  Lasher, help!”

Gunshots. 

I ran out of my tent in my boxers, carrying my rifle, struggling to put my night vision goggles on. Lasher was already out.  He had his goggles on and his boots, too.  And his rifle.  We ran toward the horses. 

In the eerie greenish glow of the goggles, I could see the horses milling frantically, Devereaux at the edge, yelling, and firing. And dimly, beyond him, I could see lions, large, thickly muscled gray shapes, surrounding the downed mare.  It was obviously too late.  One leg was still kicking a little, but she was surrounded, engulfed by the lions.  There were five or six all around her, eating.  Snapping and snarling at each other, jostling for position. Noisy, harsh, brutal.

“Christ, Devereaux,” Lasher said, “stop shooting.  It’s too late.  Don’t waste the ammo.”

From time to time several pairs of green eyes would lift and regard us for a moment.  Not curious, not threatened, not particularly threatening. Simply noting that we were there.

Off to one side, I could see a lioness standing, head down, panting.  Part of her belly was black.  It took me a minute to figure out that she was wounded – gutshot.  The blood appeared black in the goggles.  I raised my rifle, aimed carefully, and put her down.   Lasher turned to me and nodded, once.

“Well, let’s get ‘em!” Devereaux whispered urgently.  “Fuckers! Let’s take them down!”

“What for?” I whispered back.  “They already got her.”

Yeah, but they’ll come for the other horses, next.”

“No they won’t – that’s enough meat right there for all of them.” 

Unbelievable – we’re having a debate in the middle of the night, twenty five or thirty feet away from a welter of feeding lions.

“All, right, let’s go,” Lasher said. “Devereaux, Summers, you guys pack up the tents, I’ll move the horses over to the other side of the camp, and we‘ll load up and move down the road a ways.”

For all of my avowed confidence that the lions were done hunting for the night, it was still creepy, moving around in the dark, (still with the goggles on) packing everything up.  I moved fast, real fast, just this side of panicky.  And then, of course, your mind goes into overdrive, and I started thinking not only of the lions, but of what else might – even now – come bounding or padding out of the darkness to take me.  A wolf; or a whole pack.  A bear.  Smilodon, stalking and creeping.  Teeth and claws and death in the night.

Even moving as fast as I could, packing up took several minutes. The stupid goddam goggles kept slipping around, but I didn’t want to take time to re-tighten the straps. 

Lasher came around with the horses, and we loaded up as quickly and quietly as we could. And got out of there.

We rode for a mile or so, by my estimate, and then Lasher said “Hold up, a minute. We got two choices – we can stop here for the rest of the night, or press on and try to make the mountains later today.”

That choice was easy.  “Let’s keep going,” I said.

“Damn straight.” Devereaux.

“All right.  We’ll get up into the hills, anyway, and find water.  Let’s go.”

In the dark as we rode, I asked Devereaux what had happened – back there – with the lions.

“Jesus, I don’t know.   I had the goggles on and saw one, walking toward the horses, in that crouched down, hurrying way they get.  So I yelled, but it didn’t stop.  So I shot – two times –  but I missed.  But the lion stopped.  But then three more came from the other side.  They charged out and grabbed her.  That’s when I really started shooting and calling for help.”

“The bastards are too dumb to be afraid of us.”

“No, they’re not too dumb,” I said.  “It’s just that they’ve never encountered humans before.  They haven’t learned to associate gunshots with death.  So they don’t fear us, you’re right, but not because they’re too dumb.  We’re just outside any of their experience.”

“Yeah, well, I still think we should’ve killed those bastards.  Jesus.”

End of conversation.  Devereaux had not been asleep, or passive aggressive.  Just overwhelmed by the coordinated attack of a pride of lions.

 

 

 

One day, riding across a basin, through grass that grew to our horses’ bellies, we saw a pride of lions take down a camel. The hunting seemed similar to that of modern African Lions.  The pride, all females, startled a herd of grazing camels, and then chased down a hugely pregnant female.  Shortly after she was down, a pair of male lions came trotting up quite briskly, and then, at the last second charged into the lionesses already gathered tightly around the carcass, and usurped the kill.  Seen in daylight, in action, these lions were awesome.  They seemed much bigger than modern African lions, huge, and strong, and so very quick.   I know from fossil reconstructions that they are estimated to have only been twenty percent larger than modern lions, but I’m telling you, these lions looked enormous. The males snarled and swiped at the females they had displaced, females who were trying to get back and eat.  The cacophony of growls, snarls and snaps was fearsome.  Not all of the lionesses were trying to fight their way back to the kill, however.  Some of the displaced females saw us, and began to stalk us.  The camel’s panicked flight had brought the pride nearer to us, and our path had brought us close enough to the kill, that the lions thought we presented them with another opportunity.  They weren’t charging us – yet; instead they displayed that nervous half-crouched low stalking creep that we’ve all seen on the nature shows.  Three of them, large, lean and hungry, approaching us from about four o’clock.  In this convention, 12:00 o’clock is directly ahead of us, and the other hours of the clock face represent the approximate direction from which the animals (or any other attack) were coming.

Lasher said, “Devereaux, take the [pack and spare] horses and move up – slowly.  Don’t run them; don’t trot; just keep ‘em bunched together.  Summers, you get up front, too, and stay right behind the horses. I’ll drop back and scare ‘em off.”

Yeah, well, good luck with that.  You aren’t going to be able to scare them off – they don’t know us or fear us.  They see horses within the kill zone, and they are hungry.  They don’t know that the sound of a shot equals danger. They see food.

“Watch the front and flanks,” Lasher said.  He pulled up and let us pass him.  Both Devereaux and I had our rifles out, and were looking, looking, looking, every which way, for lions to come exploding up out of the grass, or from the trees.

Behind me, I heard Lasher’s horse snort, and Lasher talking to it in a low, soothing voice.  “Hold on, girl. That’s it. That’s a good girl.  Hold on here.”  That sort of talk.  I glanced back briefly, and saw he was sitting on his horse, not moving forward toward the lions, nor back to rejoin us.  Just sitting astride his horse, rifle held up, and ready.

We kept moving steadily. The wind, what there was of it, was into our faces, so I guess the horses didn’t smell the lions. In any event they remained calm, as we walked them forward.

I looked back again, and saw Lasher now, thirty or forty feet behind us, still sitting his horse. Now his rifle was down and aimed at one of the lionesses.  Still he had not fired. 

We kept moving.  Devereaux detoured around a little grove of tree, and kept us out in a more open meadow, where at least we could see (I hoped) anything sneaking up on us.  Another thirty feet, fifty feet, eye still scanning everywhere.  Hot bright sun, midges or some kind of insect, swarming and swooping over the grass heads.  Very quiet, but for the creaking of the saddles, and some bird song.

Still no shots fired.

“BAM!  BAM!”  Two shots, in quick succession. And another, “BAM!”

Shit.  I jumped.  I saw Devereaux jump a little, too.  I looked back.  Lasher was still sitting, still holding his rifle aimed at a target I could not see.  After a minute, he turned his horse, and trotted up to us.

“Okay,” he said. “They won’t bother us no more. Let’s move out.”

“What happened?” I asked’

“Well, I heard somewhere that if you don’t run before them, don’t give ‘em something to chase, that lions most probably won’t attack.  So I tried that.”

“Yeah, but what happened?”

“Well, they stopped and started looking me over.  They wanted that horse, that was for sure, but they couldn’t figure out why she wasn’t running.  And I expect my smell was unusual, and gave them something to think about.  So anyway, you could see they was thinking about what to do –whether to try to catch another dinner, or just go back to that camel, before it’s all gone.  And then one of ‘em took a couple quick steps forward, like she was thinking she’d rather eat horse.  So I put two quick shots down into the ground right under her feet.  Tried to spray some dirt and gravel up in her face.  And then she stopped and looked like she was going to change her mind and eat some camel.  So I fired again, to encourage her.  And the three of them left.  We still better keep our eyes peeled, though.”

“Yeah,” Devereaux said, “but why didn’t you just shoot them?  I mean, Jesus.”

“Well, I’ll tell you,” Lasher said. “I thought about it, but I don’t like shooting anything unless I have to.  And even more important, we still gotta think about them boys behind us.  I hope we’ve given ‘em the slip, but I’m not counting on that. And if they’re still trying to track us, finding three lions that been shot would let ‘em know for sure that they’re on the right track.  So I woulda shot ‘em if I had to, but I’d rather not.  And it worked out okay.”