How the Chalicothere Split In Two

  • Publicado el 24 abr 2018
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    Two extinct relatives of horses and rhinos are closely related to each other but have strikingly different body plans. How did two of the same kind of animal, living in the same place, end up looking so different?
    Thanks to Ceri Thomas for the very cool Anisodon reconstruction. Check out more of Ceri's paleoart at and
    And thanks as always to Nobumichi Tamura for allowing us to use his wonderful paleoart:
    Finally, thanks to Dmitry Bogdanov, Roman Uchytel, Ryan Somma and Julio Lacerda for their excellent images as well.
    Produced in collaboration with PBS Digital Studios:
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    Prothero, D. R., & Schoch, R. M. (1989). The evolution of perissodactyls (Vol. 15). Oxford University Press, USA.
    Peters, N., & de Vos, J. (2012). First evidence of a chalicothere (Mammalia, Perissodactyla) in The Netherlands. Cainozoic research, 9(2), 141-144.
    Clauss, M., Frey, R., Kiefer, B., Lechner-Doll, M., Loehlein, W., Polster, C., ... & Streich, W. J. (2003). The maximum attainable body size of herbivorous mammals: morphophysiological constraints on foregut, and adaptations of hindgut fermenters. Oecologia, 136(1), 14-27.
    Heaney, L. R. (1991). A synopsis of climatic and vegetational change in Southeast Asia. In Tropical Forests and Climate (pp. 53-61). Springer, Dordrecht.
    Churcher, C. S. (2014). A vacant niche? The curious distributions of African Perissodactyla. Transactions of the Royal Society of South Africa, 69(1), 1-8.
    Werdelin, L., & Sanders, W. J. (2010). Cenozoic mammals of Africa. Univ of California Press.
    Colbert, H. (1935). Distributional and phylogenetic studies on Indian fossil mammals. III. A classification of the Chalicotherioidea. In American Museum Novitates.
    Bai, B., Wang, Y., & Meng, J. (2011). Early Eocene chalicothere Litolophus with hoof-like unguals. Journal of Vertebrate Paleontology, 31(6), 1387-1391.
    Peterson, O. A. (1907). Preliminary notes on some American chalicotheres. The American Naturalist, 41(492), 733-752.
    Munthe, J., & Coombs, M. C. (1979). Miocene dome-skulled chalicotheres (Mammalia, Perissodactyla) from the western United States: a preliminary discussion of a bizarre structure. Journal of Paleontology, 77-91.
    Janis, C. M., Scott, K. M., & Jacobs, L. L. (Eds.). (1998). Evolution of tertiary mammals of North America: Volume 1, terrestrial carnivores, ungulates, and ungulate like mammals (Vol. 1). Cambridge University Press.
    Coombs, M. C., & Rothschild, B. M. (1999). Phalangeal fusion in schizotheriine chalicotheres (Mammalia, Perissodactyla). Journal of Paleontology, 73(4), 682-690.
    Coombs, M. C., Hunt Jr, R. M., Stepleton, E., ALBRIGHT III, L. B., & Fremd, T. J. (2001). Stratigraphy, chronology, biogeography, and taxonomy of early Miocene small chalicotheres in North America. Journal of Vertebrate Paleontology, 21(3), 607-620.
    Coombs, M. C. (1979). Tylocephalonyx, a new genus of North American dome-skulled chalicotheres (Mammalia, Perissodactyla). Bulletin of the AMNH; v. 164, article 1.
    Coombs, M. C. (1975). Sexual dimorphism in chalicotheres (Mammalia, Perissodactyla). Systematic Biology, 24(1), 55-62.
    Semprebon, G. M., Sise, P. J., & Coombs, M. C. (2011). Potential bark and fruit browsing as revealed by stereomicrowear analysis of the peculiar clawed herbivores known as chalicotheres (Perissodactyla, Chalicotherioidea). Journal of Mammalian Evolution, 18(1), 33-55.
    Zapfe, H. 1976. "Die Fauna der miozanen Spaltenfiillung von Neudorf a. d. March (CSSR). Chalicotherium grande (Blv.)." Sitzungsberichte Osterreich Akad. Wissenschaften, Math.-na-turwiss. Klasse (Abt. I) 185: 91-112.
    Zapf 1979. "Chalicotherium grande (Blainv.) aus der miozanen Spaltenfiillung von Neudorf an der March (Devinska Nova Ves), Tschechoslowakei." Neue Denkschriften Naturhist. Mus. Wien 2: 1-282. Zhou, Mingzhun, Yu
    Munthe, J., & Coombs, M. C. (1979). Miocene dome-skulled chalicotheres (Mammalia, Perissodactyla) from the western United States: a preliminary discussion of a bizarre structure. Journal of Paleontology, 77-91.
    Wunderlich, R. E., and W. L. Jungers. "Manual digital pressures during knuckle-walking in chimpanzees (Pan troglodytes)." American journal of physical anthropology 139.3 (2009): 394-403.
  • Ciencia y tecnolog铆aCiencia y tecnolog铆a

Comentarios • 945

  • Irilly Dunno
    Irilly Dunno Hace 3 d铆as +1

    Excellent video!

  • Steven Stark
    Steven Stark Hace 3 d铆as

    I love how the massive bumps on those rhino-horsey's foreheads formed because they thought headbutting each other to the death was the best way to figure out who gets all the ladies

  • Yanuchi Uchiha: Anime, Games and Ramdomness

    Therizinosaurus 2.0

  • Travis Curry
    Travis Curry Hace 6 d铆as

    A THEORY called parallel evolution

  • MacBeth Hadesson
    MacBeth Hadesson Hace 6 d铆as

    A Californian Chalicothere eating cauliflower and doing calligraphy.

  • James Dooling
    James Dooling Hace 6 d铆as +1

    A hard bone dome on your crown would help you slam nuts out of trees... Like pecan and olive trees that need a good jostle.

  • Samuel Moreno
    Samuel Moreno Hace 8 d铆as

    I'm here cause of the game ark survival 馃槄
    Favorite tame by far, but I always called pronounced it like
    kal ic O th or e um

  • Shiverz
    Shiverz Hace 9 d铆as

    I've always found Chalicothere's fascinating, so thank you so much for making this video! I learnt so much from it.

  • Alicia McMurchy
    Alicia McMurchy Hace 11 d铆as

    I enjoyed this video but I think you missed a credit for Jay Matternes whose illustrations are featured at least twice (1:49 and 5:29).

  • Groovy Bear
    Groovy Bear Hace 11 d铆as

    Hey, talking about trees... what about tree evolution ?! That'd be a great topic for one (or a few) new amazing videos :)

  • Tattoo by Bogg story
    Tattoo by Bogg story Hace 11 d铆as

    Does any other animal species have what we would call races?

    • Jascha
      Jascha Hace 20 horas

      Dogs? Horses? Cats? Rats? Mice? Ants?

  • James Huggett
    James Huggett Hace 17 d铆as

    The Dome head seemed like it would be for knocking fruit off trees or fighting

  • Pam P.
    Pam P. Hace 18 d铆as

    Lmao that ending馃槀

  • mediawolf
    mediawolf Hace 19 d铆as

    But one question not answered by this video is how the early differences weren't wiped out by interbreeding.

  • Lenny Lucas
    Lenny Lucas Hace 19 d铆as

    Is BoJack Horseman a descendant of Chalicotherium

  • RandyPantheGoatBoy
    RandyPantheGoatBoy Hace 20 d铆as

    How about Pleistocene species that may have survived slightly beyond 10,000 years ago?

  • erniemajor
    erniemajor Hace 25 d铆as

    These videos would be a lot better WITHOUT the talking monkeys in front of the camera.

  • juan Garcia
    juan Garcia Hace un mes

    So Parallel Evolution in todays time would be an example of Polar bears and Brown Bears? Or ?

    • Jascha
      Jascha Hace 14 d铆as

      +juan Garcia I'm from Germany so I don't know the English names, but there's a Wikipedia article which shows examples

    • juan Garcia
      juan Garcia Hace 14 d铆as

      +Jascha Mmmm...yea true..but so what could we compare in todays time as parallel evolution?

    • Jascha
      Jascha Hace 14 d铆as +1

      No. Polar bears evolved from brown bears.

  • Courtenaire
    Courtenaire Hace un mes

    can it throw boulders?

    (ARK: Survival Evolved reference

  • Mistershlee
    Mistershlee Hace un mes

    More proof unicorns used to exist

  • letsgetrealmedicated
    letsgetrealmedicated Hace un mes


  • Sjoerd Schuttelaars
    Sjoerd Schuttelaars Hace un mes

    question, how does nature create two body plans originating from one species when both 'potential good body plans" still have opportunity to mate with eachother?

  • Jen Leya
    Jen Leya Hace un mes

    So much science

  • Nasir j
    Nasir j Hace un mes +1

    how come all these animals even dinosaurs are not explained or have any proof from our ancestors but we got drawing and artifacts of dragons from every culture and bibles and medieval time. hmmm

    • Divinum
      Divinum Hace un mes +1

      Most of these animals and homo sapiens did not live together. They lives millions of years apart. Also most "dragon" artifacts and paintings are just fossils of other prehistoric animals like in this video or they are stories and that's it. If you think Dragons were real and these were not you are an idiot sorry, but its true

  • Nikbecool
    Nikbecool Hace un mes

    So if we hadn't hunted these monsters to extinction we could have gotten horse humans. Perhaps a Equus Erectus

    • Xeper-I-Set
      Xeper-I-Set Hace un mes

      Do you want to know how I know you didn't even watch this video?

  • 艗ufcoque
    艗ufcoque Hace un mes

    These chacilotheres look like something you'd find from a scifi-fantasy game. Too bad they don't exist anymore. They are weirdly cute.

  • James Bernadette
    James Bernadette Hace un mes +3

    Migrated here from TierZoo :)

    SYNONYMOUS Hace 2 meses

    Andsodon Grande looks like a giant buffed up hamster 馃槀

    SYNONYMOUS Hace 2 meses

    Daamn nature you creative!! 馃槑

  • William Jordan
    William Jordan Hace 2 meses

    I thought parallel evolution was what made unrelated animals look the same like hyenas and canines.

  • VidrioRevolver
    VidrioRevolver Hace 2 meses

    If these two animals lived in the same planes and areas, how come they didn鈥檛 breed with each other before their evolution branches off, hence halting the evolution process? You would think by being the same species in the same areas, they would be breeding with each other, therefore staying in the same species. Can anyone answer this for me?

  • Issou Amine
    Issou Amine Hace 2 meses

    Sorry, you made me confused here, Parallel evolution is not the aquisition of different traits for the same purpose (eating the top tree leaves) from a common ancestral state!!! this is wrong! that is a normal case of divergence! parallel evolution is the aquisition of similar traits (maybe for similar puposes) from the same ancestral state independently!!!
    see, examples in the link!

  • Wildman2012
    Wildman2012 Hace 2 meses +1

    This channel is great!

  • Simple Dude
    Simple Dude Hace 2 meses +1

    Im assembling an Ikea forniture and listening to these videos at the same time.
    Great experience.

  • Gautham StarShadow
    Gautham StarShadow Hace 2 meses

    Wait horses and rhino's are from the same family!!!! You mean unicorns are real!!!

  • ytmatx
    ytmatx Hace 2 meses

    Shizzzaaaam! ... otheriinae...

  • German Ruiz
    German Ruiz Hace 2 meses

    does anyone knows which museum has the Chalicothere complete story?

  • FaeQueenCory
    FaeQueenCory Hace 2 meses

    Obviously the skull bulges are horn mounts.

  • joe bart
    joe bart Hace 2 meses

    5:30 imagine this thing running at you at 60 mph

  • b 0 t t i n i
    b 0 t t i n i Hace 2 meses

    Im subscribed to 3 channels, Elite Dangerous (VR game/space sim), RailWay( for sleep, its a train just going), and now you guys. - I wanna learn about everything !!!!

  • katherine hughes
    katherine hughes Hace 2 meses +1

    I like this guy and Callie as hosts 馃槉

  • puttputt524
    puttputt524 Hace 2 meses

    This is what happens when you forget to do 鈥渁rms鈥 at the gym

  • poponachtschnecke
    poponachtschnecke Hace 2 meses

    Dang, so close to a more horse-like unicorn

  • JakoborRazor
    JakoborRazor Hace 2 meses +1

    Does Pterodactyl mean 鈥渙dd wing鈥 then?

  • KryssLaBryn
    KryssLaBryn Hace 2 meses

    Could you do an episode about any relationship (or not) between the 12,000 year old meteor impact crater recently discovered in Greenland, and the extinctions of most of the megafauna, and also the Clovis culture, which also disappeared around the same time? My own understanding is that, lacking such an impact crater, the impact theory has rather languished; I'd love to see it re-examined in light of the discovery.
    Thanks for an interesting and informative series!

  • I Was a Teenage TeenWolf

    The scary thing is that modern-day giraffes fit the niche left by the Chalicotheres, and are extremely specialized too. This means that if Africa dries up further, or grows weather, they'll be susceptible to environmental pressures and may not be able to survive. Same with pandas and koalas.

  • HypnoGaming
    HypnoGaming Hace 2 meses

    Planet Dinosaur is a 6 part series though.

  • Karlie Johnson
    Karlie Johnson Hace 2 meses

    I could watch 100 more videos on this type of evolution. So fascinating. 馃憤

  • Luke Payne
    Luke Payne Hace 3 meses +1

    Omg i love you guys. So great.

  • Jhon Jerome Satairapan
    Jhon Jerome Satairapan Hace 3 meses

    Giraffidae next.

  • Mesozoic Studios
    Mesozoic Studios Hace 3 meses

    Pachycephalosaurus horse lol xd馃槀馃槀馃槀馃槀

  • Alejandro Rodolfo Mendez

    you know this video is prove further that the rhynos are the supposed unicorns, horses relative with one corn.

  • Pad Carr
    Pad Carr Hace 3 meses

    Eloi and Morloks...

  • LO2L
    LO2L Hace 3 meses

    These were beasts of burden in the time travel trilogy "The Saga of the Exiles". Great books set in the Pliocene

  • Allan Richardson
    Allan Richardson Hace 3 meses

    Klingon horses maybe? 馃槣

  • Henry Law
    Henry Law Hace 4 meses

    Could that dome on the head have been a resonator to amplify their calls?

  • Digicraftmon the Crystal Gem this animal had also been a threat to trilobites and they were the ones who left the infamous 'W' shaped bite.

  • Walrus Latte
    Walrus Latte Hace 4 meses

    if the last ancestors were still around one million years ago that means prehistoric humans might have interacted with them 馃槏

  • E Dalby
    E Dalby Hace 4 meses

    So cows killed the unicorns, got it

  • Kansa City Shuffle
    Kansa City Shuffle Hace 4 meses

    The answer is the daily double

  • Meg Meg
    Meg Meg Hace 4 meses +1

    I like the horse gorilla

    • Meg Meg
      Meg Meg Hace 4 meses

      Now I like the horse cat

  • The Jackass Linguist
    The Jackass Linguist Hace 4 meses

    Does Tylocephalonyx evolve into Tylocephasteelix?

  • Jawbreaker The Hyaenodon

    Imagine if these guys never died out

  • Erin OBrien
    Erin OBrien Hace 4 meses +2

    I would like to see something on hummingbird evolution. I know they're specialized, but from where did their brilliant colours, their abilities to fly upside down, backwards, etc, and their other abilities come? What did their ancestors look like? Thanks so much for all of the great videos!!

  • Efrain DT
    Efrain DT Hace 5 meses

    馃悗wait cousin!馃

  • Pay Pul
    Pay Pul Hace 5 meses

    I thought it was a video about a mammal doing binary fission.......

  • KR P
    KR P Hace 5 meses

    They seem to be saying it was sympatric speciation but haven't said why they believe that.
    Animal sympatric speciation is pretty sketchy and ascribing it to long extinct animals is pretty dodgy.

  • Harley Fagan
    Harley Fagan Hace 5 meses

    5:50 had me dead 馃槀

  • Lute The Mage
    Lute The Mage Hace 5 meses

    Glyptodons! Megatherium! Giant ducks! Moa! Diprotodon! More videos about them pls. Literally until humans arrived - there were so many cool species. It鈥檚 so sad that we can鈥檛 ever see them again.

  • mrtonyd816
    mrtonyd816 Hace 5 meses

    I didn鈥檛 like him in 鈥渃racked鈥. He鈥檚 not any better here.

  • Shanani?
    Shanani? Hace 5 meses

    Giant rhino horse with cat thingies

  • Trigger Happy
    Trigger Happy Hace 5 meses

    Uuuum.... Cattle?

  • upcoast
    upcoast Hace 5 meses

    Fruits on trees.
    The head was to bump the trees.
    That's my guess.
    One still ate leaves the other ate more fruits.

  • thomassaurus
    thomassaurus Hace 5 meses

    What... why do I get nothing when I google shizerotheriinae?

  • rekkovi
    rekkovi Hace 5 meses

    I still don鈥檛 understand how they completely split if they lived in the same area. Wouldn鈥檛 the long necked and long armed ones still have reproduced and created one new species instead of two? Or ddi I misunderstand and they actually didn鈥檛 live in the same territory?

  • doobiesmoke15
    doobiesmoke15 Hace 6 meses

    How will our modern day horses look in 55 Million years?

  • Antoin Rodrego
    Antoin Rodrego Hace 6 meses +1


  • Zei33
    Zei33 Hace 6 meses

    Could they have cross bred?

  • Rafael Rubio
    Rafael Rubio Hace 6 meses +1

    Ilove this channel, so informative and at the same time fun to watch.

  • PattiMichelle Sheaffer
    PattiMichelle Sheaffer Hace 6 meses

    As long as you're discussing extinction of these species, you probably should mention how lifespans of species vary in general; origin -> extinction. It's very common that evolution "fails" (although that's an anthropomorphism) and species go extinct.

  • themarquess
    themarquess Hace 6 meses

    I have to say, I really don't understand evolution and I wish someone explained it to me. If the evolutionary differences between two generations are too miniscule to notice, how can they have an impact on survival and lead to selective breeding? Take a non-venomous snake, that evolves to look exactly like a dangerous snake, so that predators don't attack it. This trait wouldn't have any impact on survival until it's fully evolved. A snake that's sort of on the way to looking like the venomous one, but has all the colours and patterns all wrong, won't have a better chance at survival. So how does such a trait continue evolving in an incremental manner over generations?

  • KTo288
    KTo288 Hace 6 meses

    Any chance of an episode on convergent evolutuon, it would make a good companion to this one.

  • Jora
    Jora Hace 6 meses

    That Chalicotherium explains where CD Projekt got their inspiration for the fiend in The Witcher 3...

  • Harsh Jadav
    Harsh Jadav Hace 6 meses

    Nice but can you tell me how can I interact more with you guys馃憤

  • Xavier Lapis
    Xavier Lapis Hace 6 meses

    When the ark dossiers aren't enough

  • The_Jedi_ Priestess
    The_Jedi_ Priestess Hace 6 meses

    Parallel Evoollutiionnn I love this guy, he covers it ALL 馃槏

  • Hector Valade
    Hector Valade Hace 6 meses

    Could you do sloth evolution? plz///////:)

  • Oswards306 Oswards306
    Oswards306 Oswards306 Hace 6 meses

    I wonder what the chalicotheres would look like if they survive to our modern times.

  • Timothy Beckett
    Timothy Beckett Hace 6 meses

    Where did each type succeed in the world?

  • Timothy Beckett
    Timothy Beckett Hace 6 meses

    Is there genetic evidence to prove the 2 creatures are related?

  • tembofly
    tembofly Hace 6 meses

    They would not likely have speciated (diverged) in each other's presence. There must have been a separation for this to occur.

  • luciferangelica
    luciferangelica Hace 6 meses

    didn't watch it yet. my guess is an axe

  • Avatrass
    Avatrass Hace 7 meses

    How do you like that silver!

  • Organ Farm
    Organ Farm Hace 7 meses

    If they both occupied the same places at the same times there must have been something that stopped them cross-mating or they would never have developed such enormous differences. Perhaps it was something like a chromosome mutation.

  • Kerian Halcyon
    Kerian Halcyon Hace 7 meses

    The only issue I have with this explanation for chalicotheres is that its body structure doesn't appear to fit. The arms are incredibly long, got that...but so is the neck, and the upper part of the body, so why bother wasting energy reaching for limbs to bring closer to your mouth when you can already reach it by just standing? And if it was to break branches off of the trees and pull them to the ground, it's already physically very top-oriented, so having to bend those forelimbs to get at the food would be awkward and difficult. The claws don't appear opposable, so gripping branches must have been a challenge...
    There has got to be another reason why these animals look the way they do, but I think the current accepted explanation is kind of...pardon the pun..."reaching."

  • Necrodermis
    Necrodermis Hace 7 meses

    Damn earth killing off gorilla horses

  • Noah
    Noah Hace 7 meses

    But if they were evolving in the same place and were technically the same species while the process began, wouldn't they be breeding with one another either negating the extremes or giving them all both long necks and long arms? I'm sorry if I sound ignorant, but there seems to be a giant hole in your explanation of parallel evolution.

  • Cyrus Hale
    Cyrus Hale Hace 7 meses

    So you are saying the hump header one is what turned into the horse and the lanky one turned into the rhinoceros? Okay, now I'm confused.

  • Shaun Earsom
    Shaun Earsom Hace 7 meses

    "There are some things that evolution just can't get you out of" Maybe that's why we developed brains and tools?

  • Andre Prawardana
    Andre Prawardana Hace 7 meses

    Please cover Andrewsarchus