Xenosmilus

[@catboybananabread]

as a hearing impaired viewer of your channel i just want to say that the man-made captions on this are extremely appreciated!

[@RealPaleontology]

Great to see that they are appreciated

[@petermorrissey8497]

Me too.

[@RealPaleontology]

@petermorrissey8497 no worries I'll make sure I keep the subtitles up

[@alexmclean1216]

"V-8 muscle cars of the animal kingdom" Yes, and there is a reason that using a Dodge Challenger was a great choice, as there is a "hellcat" version of that particular pony car.

[@RealPaleontology]

Ha! Yes, and there's another reason I chose a Dodge Challenger. Last time I was in the USA I hired 1 to drive from Albuquerque to the Grand Canyon with my beautiful partner. Fun car! It's my portrait pic on my Facebook page!

[@oldsarj]

A 900 lb. cat? That's the size of a coastal brown bear. Big kitty, kitty, kitty!

[@RealPaleontology]

Very big indeed. About the size of your average horse.

[@8888Rik]

Another little gem of a video. As an evolutionary biologist, I share the fascination that everyone has with paleontology, and I've done a fair bit myself, but I lean more toward theory, such as speculation about possible extraterrestrial life, extremophiles, how life got started, viruses, and so on. And so, this video gave me much more information than I had before on Xenosmilus, and really piqued my interest in the animal. I'll be doing some metaphorical "digging" into this truly amazing animal. Thank you!

[@RealPaleontology]

Thank you. Glad to be of service.

[@leswallace2426]

Great video! I've read a lot about your work on Australian megafauna so nice to see you in person.

[@RealPaleontology]

@@leswallace2426 hey thank you!

[@petehoover6616]

I would guess that a xenosmilus eating peccaries was starving to death. What was lost 300,000 years ago from Florida that wiped this predator out?

[@RealPaleontology]

Ha! Yup, they were scraping the barrel. But lions today will happily grab a warthog when they can.

[@Tyrell-d6o]

Another cool video where I actually learned something. I was aware of Xenosmilus hodsonae but had no idea there was a bigger species called venezuelensis! This doesn't seem to be readily available info as the wikipedia page still only says there's the one species. I guess it's "real paleontology" for a reason.

[@RealPaleontology]

Yes indeed. You're actually getting your information from someone with their fingers on the pulse. Not just a talking head or AI BS.

[@toriwhite2743]

Thanks! I always look forward to your videos!

[@RealPaleontology]

Wow. Thanks so much Tori! It really means a lot.

[@terrorquetz]

WE LOVE XENOSMILUS

[@RealPaleontology]

Is pretty awesome

[@gabrielsmedleysanimaltime5826]

Fantastic analysis as always professor! It looks like Xenosmilus venezuelensis lived before Smilodon populator evolved, so Xenosmilus was the top cat in South America and Smilodon only rose to the title after Xenosmilus's extinction. I do wonder if there was a difference in the level of sociality between X. venezuelensis and X. hodsonae. I love that you decided to create this channel, as it always gives me something to look forward to.

[@RealPaleontology]

Thank you very much! And yes it Probably predated populator. Although there is a proposed early-middle Pleistocene date for S. gracilis in Venezuela.

[@robertjackson1813]

Those incisors are giving me some real repetomammus vibes.

[@RealPaleontology]

I can see that

[@cro-magnoncarol4017]

The teeth of Xenosmilus look like the teeth of a fantasy monster they purposely try to make look scary...

[@RealPaleontology]

@@cro-magnoncarol4017 yes kind of alien-looking

[@andrejspi]

Thank you for exciting episode and letting us know specifics of the anatomical detail of the Xenosmilus! I've just looked at the original description paper and their jaw closing muscles should have been massive, as you've mentioned. I guess this implies unique and divergent type of biting in the context of cat sabretooths? If it lived in Florida and similar environments, maybe it was preying on alligators? Just a thought, since you've mentioned other armored prey species with osteoderms, such as giant ground sloths and glyptodonts of South America. Some stable isotopic analysis could help here, I guess.

[@RealPaleontology]

Thank you. And yeah, I reckon it would have taken a decent size gator. Although I doubt that this was its typical prey.

[@gabrielramirez9102]

Thank you, amazing creature.

[@RealPaleontology]

Pleasure

[@jthomas8263]

prof. Wroe, that's amazing about the New South American Species of Xenosmilus.

[@RealPaleontology]

It sure is. And it's a hell of a big cat too

[@jthomas8263]

@@RealPaleontology Yeah, Manzuetti and Colleagues had name the New South American Species of Xenosmilus soon.

[@RealPaleontology]

​@@jthomas8263 I'd like to see that.

[@Woodswalker96]

I have multiple suggestions for more potential super predators, if you haven’t already planned on doing these animals: Deinosuchus, Utahraptor, Postosuchus, Purrusasaurus, Daeodon, Maip macrothorax, Hyaenodon, Cretoxyrhina, Allosaurus and the other Morrison Formation heavyweights (Ceratosaurus and Torvosaurus), Panthera spelaea and P. atrox, Crocuta crocuta splelaea, Aenocyon dirus, Borophaginae, and Dinocrocuta! Again, just suggestions, and I really enjoy your videos!

[@RealPaleontology]

@@Woodswalker96 great thanks for that. I will get around to the sooner or later!

[@Woodswalker96]

@ can’t wait to see more of your content, honestly feels like a breath of fresh paleontological air!

[@RealPaleontology]

@@Woodswalker96 thanks!

[@bkjeong4302]

The ultimate machairodont in some ways.

[@RealPaleontology]

Yes it certainly up there

[@francissemyon7971]

Thanks you for the work, the scrutiny of those big cats in your videos indeed shows how close they are from the perfect predators. Can't wait for an analysis of its biting mechanisms.

[@RealPaleontology]

It's a pleasure

[@francissemyon7971]

​@@RealPaleontology By the way, have you looked at this paper about extinct and extant toothed whale jaws muscles "Temporalis attachment area as a proxy for feeding ecology in toothed whales (Artiodactyla: Odontoceti)" It appears Basilosaurus has the largest proportional temporalis muscle of any whale studied.

[@RealPaleontology]

Hey great thanks for the heads up. I'll take a look.

[@Clearlight201]

Thanks for bringing another amazing super-predator to life with your thoughtful analysis. It's fascinating to speculate on the possible contact between Xenosmilus and Smilodon; whether they carefully avoided one another and stayed in separate niches of habitat and prey, or occasionally clashed and competed.. or maybe their ranges never overlapped?

[@RealPaleontology]

Thank you very much! And yes Competition between two such similar cats would have been Totally extreme if they did indeed overlap in space as well as time. Smilodon gracilis was almost certainly contemporaneous with Xenosmilus for some period, although we have no clear evidence that they were in the same place. It’s also quite possible that it bumped into the big North American terror bird, Titanis walleri, on occasion!

[@johnypsilantis2442]

Incredible video! Thank you once again professor. Cannot wait for more prehistoric cat videos (both machairodonts and conical toothed).

[@RealPaleontology]

Thanks for that! There will be more rest assured!

[@swaggasaurus_rex]

Love this series! Megantereon would be good. Widespread, very cool-looking cat, and said to have facilitated the spread of hominines and hyaenids from Africa to elsewhere by killing more than it ate. Would love to hear your thoughts on all this!

[@RealPaleontology]

Thanks and yes I will do this one

[@minoadlawan4583]

This cat predated on titanis

[@RealPaleontology]

Ha! In Australia we call that stirring the pot

[@MouadOuadah-lu7td]

I love the way you present the creatures absolutely one of the best and most underrated paleontology channels on youtube !! Im wondering if you can talk about the natodermi lion (the big lion skull that was fount in natodermi) And what speciesof lions is it

[@RealPaleontology]

Thank you very much. It's a pretty new channel only a few months old and not doing too badly I think. But hey do me a favor and share it! And yes I should do some extent super predators and the lion has to be one

[@LUISENRIQUEFLOREZ]

Impresionante, gracias profesor, saludos desde Colombia

[@RealPaleontology]

No problem

[@BiffBrix]

Super interesting! It's wild how many different fossil cats of late were plausibly reading polar bear sizes. Dunno if you've heard of the paleoartist Hodari Nundu, but your comments on its stockiness reminded me he has a piece speculatively depicting Xenosmilus rearing up on its hind legs like a bear. Would be very curious what your thoughts are on Lokotunjailrus as a hypercursorial saber cat if you ever make a video on it!

[@RealPaleontology]

Yes definitely heard of Hodari, does some great stuff. And yeah, Lokotunjailrus Is a very interesting. Breaks the mold but in a different way! I'd like to do an episode on that.

[@cro-magnoncarol4017]

The fact it was heavily-built like Smilodon implies it was still wrestling big prey like the former, but perhaps instead of a single, clean bite to the throat like Smilodon perhaps Xenosmilus absolutely shredded the throat of its prey & or just ripped the entire throat out. Just a theory, but it's interesting to ponder.

[@RealPaleontology]

@@cro-magnoncarol4017 I think that's pretty likely

[@johnanthonyp]

With teeth like that, I'd imagine the takeaway from a bite on any area of its prey would prove very telling and mostly fatal.

[@RealPaleontology]

@@johnanthonyp yep, I think that was the plan!

[@johnanthonyp]

@@RealPaleontology Probably had the luxury to loiter after the strike in the same vein as the Komodo Dragon.

[@RealPaleontology]

@@johnanthonyp yep, although it didn't have venom!

[@ShannonShanks-il8ip]

I'm torn between being very grateful to be separated by many many years from these cats and a crazy desire to pet them. To see one of these amazing cats in person would certainly be an experience. Most likely a completely terrifying one.

[@RealPaleontology]

Oh I would love to see one! I just want some thick bullet-proof glass between me and it!

[@Vivisectus]

Also they should hurry up and clone the Mammoth and Homotherium because I really want to see them and damn the consequences :P

[@RealPaleontology]

I'll drink to that

[@Snugglez187]

Be glad you weren't born at that time, then, because it sounds like you would have been a victim of natural selection. Lol

[@petehoover6616]

I wondered about the carnaissal teeth; peccary bones made me think the starving xenosmilus might crunch bones like a hyena. I already had seen raccoons had molars, but cats and dogs don't. Xenosmilus doesn't have molars either, but hyenas have them. 4:48 shows very large and sharp carnaissals. Big enough to cut off the hand that's holding the mandible. But I wouldn't think that cut marks on gomphothere bones would come from those carnaissals. (I'm stumped when it comes to figuring out which gigantic S. American critter vanished 300,000 years ago but whatever it was, that can be assumed to be xenosmilus's usual prey) Trying to figure out why xenosmilus had those weird incisors could be interesting. Horses have curved incisors. Why would a cat need them?

[@RealPaleontology]

Hi, technically cats and dogs do have molar teeth. But you're right in that cats especially have few if any surfaces that are well adapted to process bone. And yeah, those incisors are something else. They probably helped to tear out big chunks of flesh, in much the same way that shark does.

[@Notacladist]

More good stuff. One quibble: on this side of the great pond, we pronounce it PEK-a-ree, rather than pek-AH-ree. Them tayasuids is ours, dontcha know.

[@RealPaleontology]

Thanks for the heads up! Next time I'm on your side of the pond I'll be sure to bear it in mind! And now you know how to pronounce it when you are on my side!

[@Notacladist]

@@RealPaleontology Fair enough.

[@Morrison-saber-tooth]

Someone should make Jaws's parody poster showing an apeman swimming in lake and shows xenosmilus emerging from deep of the lake and it would have title 'sabres'

[@RealPaleontology]

Now there is an idea let's see if someone takes it up

[@Auldron]

Smilidon has been dethroned. Interesting. Xenosmilus looks like it was crossed with a Creodont!😱 Did it sharpen it's mouth every time it open and closed? Lol

[@RealPaleontology]

It does have a slightly primitive kind of look

[@TalynElliott]

I liked the pinhead comment. I haven't gotten a chance to see the fossils in person, but I have always thought the pictures make the head look way smaller than that of smilodon.

[@RealPaleontology]

Thanks and yeah, Larry Martin Makes this point in the initial description.

[@eduardschmidt7108]

Beste Grüße aus Deutschland ! Steht eigentlich Barbourofelis irgendwann einmal in Ihrem Programm? Danke für alles und weiter so....

[@RealPaleontology]

Thank you and yes I will do this cat it's definitely on my list

[@Vivisectus]

One thing that bugs me is this: where are all the predators with specialized hardware like these cats had today? Surely teeth are not so metabolically expensive that they would not re-appear if they were useful. So why do lions have to spend ages slowly choking those great big water buffalo to death these days? What has changed in terms of evolutionary pressures?

[@RealPaleontology]

It's not the metabolic cost of the teeth. It's the trade off between the risk of breakage and the need for a high density of large prey. Sabertooths are specialists. The good for one thing and they're very good at that. But if they're density of large prey Falls below threshold they are screwed because their way over engineered to take smaller prey

[@Vivisectus]

@@RealPaleontology Ah I see - so I need to look at a complete package: big teeth, large muscle attachments to power the bite, strong arms and claws to deliver the bite, enough mass to tackle this large prey, which needs to exist in high enough density to make all this "kit" worthwhile. This is there sometimes for regular lions today if the buffalo are plentiful, but also regularly not there and then they have to survive on smaller prey and deal with shortages... which bigger cats would have harder time with and cannot survive as well as regular lions?

[@RealPaleontology]

Yup, you are absolutely on the right track! It just so happens that I'm in the middle of writing up an episode I'm calling: "Why be a sabretooth?". I will go into this in more detail.

[@Vivisectus]

@@RealPaleontology looking forward to the video - and thanks for clearing that up, I always wondered about that!

[@RealPaleontology]

No worries mate, that's what I am here for

[@ericdubert5983]

Let's get nutty and see what sticks, lol. I'd love to know, pride or solitary hunter? Smilodon could protect his fragile teeth with party hunting strategies setting up a fatal, if slow, killing bite. Xenosmilus seems to have a brawler's bite with a higher bite force. It suggests to me that he was an independent operator. Independent operators should get higher consideration for the Super Carn-Mega predator prize. With the heavier musculature and potentially much higher bite force, there is something very strange going on and I read it as a fishing cat that doesn't want to get wet. The shark arrangement may have been the crossroads of Mass Damage Blvd and Gotcha Way. If Xeno in Floridan and Venezuelan swamps, marshes and lowlands were similar to today they could have hunted water dwelling creatures and lifted them out of the water with a bite and musculature designed to land large prey onto a suitable perch attempting to avoid going in like bengal tigers. Although, South America is known for the jaguar that swims underwater during hunts at times. The radically different bite pattern may also be accompanied by webbed toes and other advantages for the biome and ultimately from its perch extracting or dragging the prey up onto land. moving the prey to safety to avoid predators like leopards and many other cats. The possibilities are really endless without further information. Very intriguing. Great Video!

[@RealPaleontology]

Yes, there's definitely something different going on. I'm not so sure about the bite force thing. The sagittal crest is big, but then its head is relatively small....

[@LadyhawksLairDotCom]

I'd bet you'd like a look at the frozen Homotherium cub. That discovery must have been over-the-moon exciting for you. :)

[@RealPaleontology]

Yup! Amazing stuff! Now I just want to see an entire perfectly preserved adult!!

[@tobilikebacon]

You should definently do a video on one of the big panthers like P. atrox or P. fossilis

[@RealPaleontology]

Yes you're right I have to do atrox

[@positrac-b9b]

Any kind of sabertooth cat must've had insanely strong head and neck muscles

[@RealPaleontology]

That's true. Although some head stronger Nicks than others

[@athos9293]

I know that the video is about xenosmilus and that i should probably be praising it instead, but man, YOU ARE SO COOL.

[@RealPaleontology]

Hey thanks!I'll take that!

[@WillaGwenni]

Great analysis, thank you! I have a quick question: My OKX wallet holds some USDT, and I have the seed phrase. (alarm fetch churn bridge exercise tape speak race clerk couch crater letter). How can I transfer them to Binance?

[@RealPaleontology]

Thanks for that! And if you’ve got a bit of extra cash, my suggestion would be to donate it to a worthy cause, like “UNICEF” or maybe even “RealPaleontology”. Of course, I’m not a financial expert, so please, seek professional advice first.

[@evilcow666]

How would Xenosmilus and Smilodon reduce competition with each other? They seem very similar in terms of lifestyle and diet. Im guessing they had some differences in terms of how they killed their prey. Do we know what they might be?

[@RealPaleontology]

Good question. I rather suspect they went for similar size prey. So maybe they preferred different habitats? Ultimately it seems they were both nudged out!

[@rubric-eo5yj]

can you do a video on amphimachirodus giganteus,that sabretooth has a current mass estimate of almost 500kg

[@RealPaleontology]

Yes I will definitely cover Amphimachirodus although it might take a month or two.

[@bigred8438]

When I see depictions of these large cats killing prey, I think of images or video I have seen of one: a Donkey taking a Hyeana to task by biting hard on it head. and two: a camel throwing a randy Donkey around like a rag doll. I have also seen Rhinos lift the front of a vehicle off the ground, and the same for a rampaging Bull in Spain. There is plenty of footage of predators in Africa being shown the door as it were after encountering push back from herbivores some roughly their size, So Wilderbeast, Hippos, Rhinos, Giraffe, Cape Buffalo, Zebras, Thompson's Gazelle, the Gemsbok and even Warthogs driving off predators. Did the big cats from antiquity really have it that easy when it cam to facing down a prey species?

[@RealPaleontology]

Well it definitely happens. Sometimes the little guy wins. But playing it by the numbers put your money on the big guy

[@Tony.Ceyfm557]

Next can you do an informational video on megistotherium and if the 1300kg estimate by Dan folkes reliable and if megistotherium was related to canines?

[@RealPaleontology]

Sounds very interesting I'll take a look

[@Tony.Ceyfm557]

@ thanks godbless you ❤️✝️

[@NormanF62]

You have finely tuned hyper carnivores and Xenosmilus was either an experiment or the end of the line. Once its prey disappeared, it became extinct. Success is no guarantee attributable to the fact Nature doesn’t play favourites. Charles Darwin would be happy and gratified discoveries like this illustrate how evolution is the force that exerts itself on every living thing that has ever existed. In the wondrous variety of life all around us.

[@RealPaleontology]

For sure no species last forever

[@kristopherstepp3250]

It’s interesting that it is shown primarily with black fur.

[@RealPaleontology]

Yeah I don't think there's any particular scientific reason for that

[@jessehutchings]

4:47 Good Lord now that is a TERRIFYING dentition. If I had to guess this jaw excelled at biting limbs and breaking bones

[@RealPaleontology]

Tearing out throats, for sure. Breaking bones, not so much.

[@jacksonmoore4159]

its build and body was more like smilodon fatalis at 600 lb and 6 ft also it wasnt coexistant with s. fatalis, the type site is early irvingtonian in age which is like 1.5 mya, s fatalis didnt live that early

[@RealPaleontology]

@@jacksonmoore4159 yes I do believe I make that point in the video

[@RealPaleontology]

@@jacksonmoore4159 no, 1.8 is the maximum age. It could be as young as 300,000 yrs

[@jacksonmoore4159]

the source you had in mind interpreted the land mammal stage as xenosmilus's exact range which is not accurate, im looking at the actual fossil sites and seeing how old those sites are. it being around 300,000 years ago makes little sense, it and smilodon fatalis were the exact same size and lived in closed habitat and both preferred big prey so thats not really sensible. xenosmilus coexisted with smilodon gracilis. in reality xenosmilus probably went extinct due to habitat loss in a glacial period since a drier climate would reduce open space avialable. smilodon fatalis appearance was probably in response to changing habitat, as well new prey and competition coming into america from the bering strait

[@jacksonmoore4159]

@@RealPaleontology also im not berating, i just love the discussion:)

[@RealPaleontology]

Very hard to be sure of any of these dates. There are so few. We certainly can't be sure of anything there, except that the oldest one was definitely older and the youngest one was definitely Younger. But either way it likely coexisted with Smilodon and that's very interesting. You has Some interesting further speculations there!

[@framerofworlds9984]

what about the American Lion?

[@RealPaleontology]

Yup. P. atrox is within that size range too. In the vid I'm just comparing it to other sabre cats.

[@Harisankar.P]

Honestly the sabertooths and pantherine cats can be compared to homosapiens and neanderthals.One focused on agility and speed,while the other focused on strength and dexterity

[@RealPaleontology]

I think that's a fair analogy.

[@metal87power]

xeno- from xenomorph alien??

[@RealPaleontology]

Looks a bit like that doesn't it

[@joemanco-no4jy]

Dear Doctor, are their any other mammalian predators whose incisor dental alignment is curved like that? I don't remember any. Were the canines serrated on both sides like Homotherium? What about serrations on other teeth?

[@RealPaleontology]

Hi, yes, Homotherini in general tend to have a more curved anterior dentition, but Xenosmilus takes it to an extreme.

[@RealPaleontology]

And yes all of the incisors are serrated too. Kind of a cross between a white shark and a Komodo dragon!

[@petehoover6616]

​@RealPaleontology am I going to have to MAKE a scimitar tooth out of a rib bone and shoot a KZbin video of how it works and how it doesn't? (You can't twist it)

[@RealPaleontology]

I'm not sure what your point is, but yes, I'd love to see that!

[@petehoover6616]

@@RealPaleontology 40 years ago I made a weaving sword for a backstrap loom out of a section of beef rib bone. Made many items with it and even 40 years later it's still sharp. I could make a scimitar tooth copy fairly easily.

[@gufishanemometer6450]

Cool af

[@RealPaleontology]

@@gufishanemometer6450 thanks!

[@robertmartinjr.4537]

I would take the American Lion Mosbach Lion or the Ngandong Tiger over any Sabertooth Tiger species.

[@RealPaleontology]

In which context? As a predator of big prey, or as a kleptoparasite?

[@robertmartinjr.4537]

@RealPaleontology everything. Size bite force speed strength. Plus, those teeth were fragile. I've seen many Sabertooth skull specimens at the Labrea Tarpit t Museum . Many had broken fangs. If these cats' teeth were broken, they most likely have to survive in a pride. I mean, they are an impressive predator species, but they were a highly highly specialized carnivore. Much of their success depended on their oversized but delicate canines. Ancient Lions and Tigers of the same era were pretty much the same as their modern extant species but much larger. Those lineages survived, and the whole Sabertooth cats lineage died out.

[@robertmartinjr.4537]

@RealPaleontology I don't know what contemporary rivals Xenosmilus had in its habitat. But I do know that the American Lion had formidable rivals here in North America during the pleistocene epoch such As the Giant Short Faced Bear, Smilodon Fatalis,Homotherium, Giant Jaguar and Dire Wolves. All of them were serious hyper carnivores.

[@RealPaleontology]

Xenosmilus hodsonae was Pleistocene too. Early to mid. It would have overlapped in time, and quite likely space with Smilodon gracilis and Titanis, among others. The species you allude to are mid or late Pleistocene. And yet it was a long time there in the late Pleistocene. It is extremely unlikely that Arctodus simus was a true hypercarnivore.

[@RealPaleontology]

Xenosmilus venezualensis, Smilodon populator and Machairodus horribilis are all in the same ballpark as Panthera atrox. They may have grown bigger or smaller than atrox. There are insufficient data for anyone to draw a firm conclusion of this. With respect bite force, definitely, there is no doubt that P. atrox had a more powerful bite. You might like to read some of the journal articles written on the prediction bite force in mammalian carnivores. Happy to send you copies if you like. You might also like to watch the videos I've done each of the species. On the other hand, detailed analyses of the proximal and distal limb bones these little doubt that these three sabrecats had far more powerful necks and forelimbs, more stable postures, and were far more effective wrestlers. Certainly, the sabre cats all had a much higher risk of canine breakage. But there are well recorded instances wherein a sabertooth has driven a huge canine clear through the skull of another big cat, likely causing instant death. If it came to a life-and-death struggle I suspect that Smilodon would have taken the risk. In short, one on one, I think it could have gone either way.

[@petehoover6616]

Sometimes, boys age 11-14 need to give their grandmother a gift, but they have no money and Grandma has everything she needs. Does Grandma crochet? The boy can make crochet hooks out of deer leg bones superior to any crochet hooks Grandma can get. (I suppose this works with sheep shanks as well) If you take the deer leg bone from a farm dog whose gotten tired of chewing on it, those seem to be best as dog saliva washes the fat out of the bones. You need to carve splinters out of the bone about 1/8" thick and maybe 6"-8" long. Do not attempt to saw across the diameter of the bone as if it were wood: the bone will spiral fracture and the gash it will leave in your hand will show that the different hardness of tooth enamel and solid bone isn't all that important. Lay a hacksaw along the length of the bone and saw that way. The ancients had burins that they would drag along the length of the cut for this reason, using the burin as if it were a single saw tooth. Once you have sliced out the splinter, use sandpaper to soften the 4 89° angles of the edges so Grandma doesn't get cut when she tries to use it but don't round out the splinter: Grandma will need to twist the crochet hook as she uses it and if it's round that's harder. (Been there. Done that.) Then you can use an Exacto-knife or a piece of a stone flake (if you're cool) to carve the head of the crochet hook so it catches the wool Grandma is trying to snag on it. It's easier to carve the business end of a crochet hook than I'm making it sound. Finish the back end with sandpaper so Grandma isn't staring at a piece of raw knuckle bone when she's using it. This is supposed to be beautiful. Grandma will love such hooks because they are a quarter of the weight of a metal hook, and unlike a metal hook, they don't get greasy and slick. The bone is strong enough to hold up under heavy use, and different from a wooden hook (been there too) no splinters will catch the wool. Grandma may want several in different sizes. If the boy can take a few crochet stitches with the hooks to make sure they will work, Grandma will love them. Raw wool has lanolin that will get into the bone and keep it from cracking for at least 40 years. I once made a 5-string lyre to see what the pentatonic fuss was about. Neighborhood Eritreans bought every lyre I made. I use wire strings, which are heavy. To make the bridges for these lyres, I carved beef leg bones from marrowbones I'd cooked in a pressure cooker for onion soup. Ate the soup, and let ants eat what they could find on the bones for awhile. Then, I carved them into the shape I needed. To carve bone, hold the knife at an oblique angle to the bone so: _____/____ moving the knife to the right. The reason to include this story in a paleontology thread is to show the difference between gracile and robust. The beef bone is much denser and heavier than deer bone. Don Dust's Paleotracks YT just made a video where he breaks deer leg bones by throwing boomerangs at them. You can't do that with a cow leg bone. (By the way: smashing a robust long bone between two rocks to get the marrow out is kinda dangerous. When working with bone, avoid spiral fractures. Wear a face shield if you're gonna do what the Paleontologists all say primitive people did, and you try to smash the bones with rocks) The heavy dense bone transmitted the string vibration to the sounding board much better than using some softer and more yielding material such as the maple used for violin bridges.

[@RealPaleontology]

Fascinating!

[@ksoundkaiju9256]

I call it the shark tooth cat

[@RealPaleontology]

Sounds appropriate

[@PredatorAlienate]

As a rule-of-thumb for limbed vertebrates, the height of the sagittal crest is inversely proportional to the size of the cranial capacity. Strong jaw muscles can preclude the development of a big brain, and vice versa. Question: Did Xenosmilus have a proportionately smaller brain than Homotherium? If so, would the cat's diminished cognition rule out the ability to track and chase game over long distances? Was Xenosmilus an obligate ambush hunter?

[@RealPaleontology]

Hmmm. I am familiar with this argument regarding the relationship between brain volume and sagittal crest dimensions. But this argument that temporalis size may constrain brain volume is a contentious one. We need to be careful that we not confusing cause-and-effect here. There is a strong allometric component in this relationship. Larger animals tend to have larger sagittal crests. This doesn't necessarily imply proportionately larger muscle size. As animals get larger, their brains do get relatively smaller, leaving less surface area on the skull the attachment of muscles. The development of a sagittal crest may simply compensate for this. But you raise a very interesting point, the large sagittal crest Xenosmilus may just have been needed to provide additional surface area because it's brain was relatively small, unfortunately I don't think the brain volume data has been published for Xenosmilus. Larry Martin does suggest though that its skull was relatively small, so I suspect that maybe it's brain was too! But don't quote me on that!

[@jacksonmoore5696]

Anyway our debates aside what do you think of my theory regarding niche partitioning amongst ice age Australian predators We ain't got isotopes like we do elsewhere so this is pure speculation. I think quinkana would have probably preferred play like maybe large ish kangaroos and the large wombats, since being 10 ft long at least it was a little too small to go after the giant animals, but it's serrated teeth indicated it was a macro predator I believe the marsupial lion was a specialist in hunting and killing the large browsers of the era like the short faced kangaroos or the macropus kangaroos and the ground sloth like diprotodontian palorchestes, since all of those animals were of an appropriate size bigger than it but not so big it couldn't overpower it plus it would have needed some kind of ambush cover and bushes would be logical and browsers of course would eat from bushes I believe megalania was probably a specialist of giant diprotodontians specifically diprotodon. Almost everywhere we find it we also find megalania. And just using the modern-day monitor lizard as comparison a modern-day monitor lizard can eat 80% of its mass in a single meal and so it usually goes after a massive prey so it can eat a lot in one meal and not have to eat for a while. Megalania probably wouldn't have been very fast and it couldn't even breathe when running so it wouldn't have been a fast animal plus most of the big kangaroos would have been very fleet-footed and they wouldn't have been as heavy as megalania so it would have been a scenario of a lot of effort but little gain. Diprotodon was perfect it was too big for any other animal to kill but perfectly big enough for megalania to kill and it was so heavy that it couldn't run fast

[@RealPaleontology]

Mmm I'm going to have to think about that

[@jacksonmoore5696]

@RealPaleontology also my facts about megalania are inferences from the Komodo dragon IE Komodo dragons can't breathe when running and they eat a huge amount of their weight in a single meal

[@RealPaleontology]

Sure, but they require far less food overall... and so pound for pound have far less impact on overall ecology. You should watch my video on Megalania for more info.

[@jacksonmoore5696]

@@RealPaleontology I'm aware I just treat the Komodo dragon like a smaller version of megalania

[@jacksonmoore5696]

@@RealPaleontology also to represent the Paleo fauna of your native Australia you need to cover the toolebuc formation of early Cretaceous Australia and expose the eromanga sea Kronosaurus Eromangasaurus Cratochelone Platypterigius

[@jessehutchings]

This would have been an absolutely jaw dropping animal to watch take a kill

[@RealPaleontology]

From a safe distance!

[@darthphilfy]

It's impressive, but still not as scary as a Drop Bear.

[@RealPaleontology]

Absolutely right

[@stevenlaube7535]

I had a Dog that had teeth with similar wear pattern she was about a meter high and suffered from a Autoimmune diseases and loved bones she crunch through she could eat a rib of a bull like it was butter ,this creature looks like it would strip meat like a bonnier in an abattoir,, , the saying the nearer the bone the sweeter the meat the fat a bit like cream ,

[@RealPaleontology]

Interesting. I don't suppose you have a photo?

[@stevenlaube7535]

@@RealPaleontology not so as to exposes her teeth in such a way one could tell she was a a bull mastiff cross greyhound did not have the overhang flesh of the mouth of a bull mastiff leaner head where is where the Autoimmune diseases was diagnosed her jaw muscles wasted so to give her a crest

[@RealPaleontology]

interesting story

[@rkozakand]

'from whence' is redundant. the word 'whence' means 'from where'. If one says 'whence', the 'from' is already present in the meaning.

[@RealPaleontology]

Yeah but it's such a cool word

[@z1az285]

There is no question Xenosmilus was a homothere on steroids but why did it not spread deeper into South America (south of Venezuela that is). Clearly Smilodon fatalis and populator outcompeted it. Is there any evidence that xenosmilus avouded bone like H latidens or seru? could that be one factor since smilodon consumed bone?

[@RealPaleontology]

It's not really clear whether it overlapped with Smilodon. It was certainly not a heavy consumer of bone. But then no saber tooth was.

[@909mcronald]

Is a seprerated species right? Like is not relate to lion and tiger

[@RealPaleontology]

Absolutely a separate species. But it is still a member of the cat family. I suppose you could call them cousins.

[@909mcronald]

@RealPaleontology thank you👍

[@jacksonmoore4159]

it also lived alongside titanis the terror bird and both likely competed for big prey

[@RealPaleontology]

@@jacksonmoore4159 yep although the big bird likely preferred more open environments

[@jacksonmoore4159]

@@RealPaleontology unlikely, the view point of larger terror birds being open space animals is not considered that viable anymore when you look at the evidence, studies show they couldnt make sharp turns when running only capable of running in a straight line, they were immensely heavy, i mean an estimation of paraphysornis weight from larramendi had it as heavy as a grizzly bear, plus these birds are tall asf and cant crouch, theyd be sitting ducks the leg proportions were ill suited as well, thanks to llalawavis we have a better idea of their leg anatomy and their tarsus was proportionately shorter than a ratite bird, meaning they werent as capable runners and many of the giant terror birds show clear signs of preferring mixed habitat, like kelenken lived in a scrubby woodland enviroment, titanis is thought to have lived in open pine woodland or oak scrub, and the colombian giant terror bird lived in the la venta which is a mixed habitat, which was highlighted by degrange in that paper. titanis and xeno would have competed but probably what happened is xeno was fleixble living from swamp,to thick forest, scrub or woodland, all it needed was ambush cover. xeno has been found in a variety of habitats like that while titanis is known from mixed habitat and xeno and titanis were found in some of the same quarries

[@RealPaleontology]

I think we are splitting hairs here Jackson! I'm not suggesting that all species of phorusrhacid were entirely restricted to open grasslands (and never have), nor that Xenosmilus and Smilodon were entirely restricted to closed forests. Could Xenosmilus hodsonae have overlapped with Titanis walleri? Sure. But I think it's extremely likely that their preferred habitats were quite different, as were their prey choices. Xenosmilus was a big game specialist, Titanis was not. So, even where they did overlap, the competition was not great.

[@jacksonmoore4159]

@@RealPaleontology degranges studies contradict the idea of larger terror birds being small game hunters a 2021 paper of his interpreted the extreme adaptations of ther larger terror bird skulls as being suited towards a specific niche, hunter of large prey. the smaller birds had distinctly different skulls more like sereima skulls once again duane naish pointed out "no modern predator grows as big as titanis or kelenken just to hunt rabbit or gazzele sized prey" i noticed how terror birds had wide gapes, blade like cutting edges of the beak, and similarities to the marsupial lion as well as biomechanical similarities to allosaurus. it was my interpretation terror birds killed by using their beaks as meat shearers to kill through blood loss i contacted degrange and he confirmed such a strategy was biomechanically plausible at the very least a 500 lb warm blooded predator cannot sustain itself by eating small prey, predators expend large amounts of energy to hunt and are rarely successful, its already difficult for small hunters to kill small prey, but bigger ones? its a case of more effort but less gain

[@jacksonmoore4159]

@@RealPaleontology i appreciate your studies and contributions to paleontology but that 2010 paper of andalgalornis is a terrible thing to form a consesus on the larger terror birds andalgalornis was 5 ft tall 100 lbs, compare that to the 6-8 ft tall and 500 lb terror birds, andalgalornis was built completely differently to its bigger cousins, it skull wasnt as reinfornced, notably the back wasnt as broad as kelenken and the the crest on the head is much smaller. andalgalornis was of a different subfamily than the mega terror birds and allometry wasnt accounted for, which i know well enough is something you must consider andalgalornis was a mid sized predator so of course it doesnt seem well suited to kill big prey, its not of the same ilk as the mega terror birds, andalgalornis was a terrible proxy to infer the behaviour of the bigger terror birds, like using a chihuahua to find out the feeding habits of the dire wolf

[@EricBakke-gx3vk]

U forgot the Maine

[@RealPaleontology]

Thanks for the heads up

[@chrissoto7187]

Pounce Chomp large chunks Wait for pray to bleed out

[@RealPaleontology]

Yeah I think that was the plan

[@gordonprice695]

That naming has always made me laugh. Obviously paleontologists have zero knowledge of blade weapons, because a Dirk is knife (with a straight blade at that), and a Scimitar is a rather large sword. Kukri toothed and scimitar toothed for short and long respectively would have made MUCH more sense. If only paleontologists played more D&D. 🤣

[@RealPaleontology]

You paint with a very broad brush there. Pretty sure most paleontologists know the difference. I certainly do. But I didn't coin these terms

[@imaxinebrown694]

If he had teeth that long he wouldn’t be able to eat ….

[@RealPaleontology]

These are pretty short teeth for a sabre Cat

[@GentalmanLout]

Dirk: a short dagger A simitar: single-edged "sword" with a curved blade So we gonna call the one with long teeth the short dagger one. Makes perfect sense . . .

[@RealPaleontology]

yeah - it wasn't me who assigned these labels

[@Davidj-r8l]

Interesting video.thanks.yea it may have been badder than populater or smilidon

[@RealPaleontology]

Glad you liked it

[@RealPaleontology]

Yes, absolutely.