Multituberculates: 'Rodents' of the Mesozoic

Multituberculata (commonly known as multituberculates, named for the multiple tubercles of their teeth) is an extinct taxon of rodent-like allotherian mammals that existed for approximately 166 million years, the longest fossil history of any mammal lineage. They eventually declined from the late Paleocene onwards, disappearing in the late Eocene, though they might have lived even longer into the Miocene, if Gondwanatheres are part of this group. More than 200 species are known, ranging from mouse-sized to beaver-sized. These species occupied a diversity of ecological niches, ranging from burrow-dwelling to squirrel-like arborealism to jerboa-like hoppers.
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[@SawdEndymon]

Criminally underrated channel. PS: would love to see a video on the other extinct mammal group, the Dryolestids

[@dr.polaris6423]

Great idea :)

[@aberonharmon3710]

Criminally underrated channel covering a criminally underrated group of animals

[@eliletts1680]

I never knew that multituberculates lived past the K-Pg extinction event or grew to megafaunal sizes! Thanks for posting! I really learned new things from this video!

[@choptop81]

It's crazy to think that they were the dominant lineage of mammals for so long, our most successful cousins over the longest time frame, and now they are just completely gone and are obscure and unknown to most people. Pretty sad

[@sciencefictionisreal1608]

have you ever heard the hypothesis that multies were replaced by passerine birds? Benjamin Burger discussed this on his youtube channel. He suggested that since many multies were specialized seed eaters, the arrival of passerine birds would have meant big competition.

[@robertgotschall1246]

I remember studying these things as an undergraduate in the 60s. At the time it wasn’t certain whether they should best be described as hairy lizards or scaly rodents. Not much was known besides their dentition and this was often found in ant mounds since ants dragged them to the surface while digging their nests, the remains being not much larger than sand grains. Back then continental drift was a brand new subject and not as well understood either.

[@LoudmouthReviews]

It has been confirmed that one of these makes a brief appearance in Prehistoric Planet

[@thedarkmasterthedarkmaster]

I must wonder why they were outcompeted and went extinct, if things had just been slightly different it is likely they would still be alive to this very day. Of course this could be argued for many mamal groups

[@dr.polaris6423]

Yeah it's a bit of a head scratcher! Their demise seems to be linked to changes in climate as much as competition from Eutherians.

[@xenoidaltu601]

@@dr.polaris6423 What about posture and locomotion? Maybe they went extinct because they were too slow at evolving erect limbed posture necessary for running in the open field that was slowly replacing rainforests.

[@Aridzonan13]

The level of detail in your videos is amazing. I watch this channel, because I'm constantly exposed to extinct species I had no idea existed. And I've been researching this subject for years.

[@wolfie1703]

if you or a loved one was diagnosed with multituberculates, you may be entitled to financial compensation

[@tutubism]

i guess you could say these were the OG "rodents" before the emergence of true "rodents" after the K/pg extinction event.

[@batspidey7611]

Hey, dude, love your videos. I’m always learning new stuff and I just recently subscribed to your channel.

[@dr.polaris6423]

Thank you! I’m so glad you find my videos informative.

[@TheFoshaMan]

Those were the original rats, holy cow (I know they weren't closely related to rats but you know what I mean).

[@cosmo6122]

One of my favorite channels of all time :)

[@rangerg7278]

Thank you! I had been hoping someone would do a cogent video on this group of mammals. I will review it again when I am more awake. :)

[@lightningboltt5437]

Love your channel Btw can you do a video on the PETM and its ecological effects

[@Grant_Scarboro]

Nice work!

[@arnaldorentes5371]

Thank you, doctor.

[@siyacer]

I wonder how they gave birth. Small pelvis suggests maybe it gave birth like a kangaroo

[@dr.polaris6423]

Yeah they almost certainly gave birth in a marsupial-like way.

[@foxhound963]

Kind of like a panda maybe?

[@TedShatner10]

@@dr.polaris6423 They WERE marsupials in the broadest sense, since the Opossum emerged not so long after the KT extinction.

[@Grant_Scarboro]

For some reason, this wonderful video of yours didn’t appear in my notifications. WTF?

[@dr.polaris6423]

Sorry about that! KZbin notifications are weird.

[@Grant_Scarboro]

@@dr.polaris6423 No worries. It's in no way your fault.

[@jonnyqwst]

Another home run stay cool bear dude

[@rebellion795]

How about the leptictidiums! I mean if you want to go for strange how about verulicolia for stanger

[@juanjoyaborja.3054]

Ancestral to placental mammals

[@tiagoasafe8394]

👏👏👏👏👏👏

[@isaacthedestroyerofstuped7676]

I'm assuming you've already seen the bombshell on spinosaurus. What do you think of the new finds?

[@dr.polaris6423]

Yes I have. Very fascinating stuff; I had always thought of Spinosaurus as a semi-aquatic animal, but that tail is very weird! I didn’t think we would ever see such a thing, giving the fragmentary history of this genus.

[@isaacthedestroyerofstuped7676]

@@dr.polaris6423 It truly is the platypus of the mesozoic! Head of a crocodile, tail like a fish, quadrapedal, fish eating, possible knuckle-walking, schoolbus sized theropod with a massive sail on its back! I wonder what a further evolved form of its lineage would've looked like if it had survived.

[@dr.polaris6423]

@@isaacthedestroyerofstuped7676 I know right! Lots of speculative artworks have depicted fully aquatic Spinosaurs, which is an interesting idea.

[@curiousuranus810]

One has to wonder just what sent them to the grave and how much richer the world would be with them now.

[@MrMerlinsMagic]

Is there anyway you can record your programs at a higher level? I enjoy your channel but have a difficult time trying to hear without earbuds. Thanks!

[@mimemouse997]

I wonder why they all died out.

[@TedShatner10]

These long extinct rodent cousins were much more like the modern marsupials, their closest living relatives? If so, one factor in their eventual demise when replaced by "true" modern rodents, may have been their less developed corpus callosum, if they were the closest ancestors to marsupials and descendants of monotremes (while rodents are placental mammals with more developed brains and more communal behavior).

[@shroomzed2947]

They might not be mammals at all. Their head morphology and chewing method resembles some mammaliaformes than anything close to metatheria.

[@TedShatner10]

@@shroomzed2947 But they ARE modern mammal ancestors, with fur/hair, warm blood, and reproduction (quite plausibly) akin to modern marsupials, with their form and function akin to modern rodents due to convergent evolution.

[@shroomzed2947]

@@TedShatner10 Those features are not enough for an organism to be classified into the crown mammal group. Skeletal morphology is extremely important. There are a good number of cynodonts and mammaliaform animals that have the features you've described but are not mammals.

[@TedShatner10]

@@shroomzed2947 Cynodonts are Triassic era proto-mammals and may've likely been egg layers.

[@BlackpilledSaihara]

Marsupials actually not that far from placentals in terms of brains. Yeah they have no neocortex and "tough body" but their brain is around the same size as placentals. Kangaroos are smarter than deers, for example. I think this myth comes mostly from antropocentristic views on biology. There's a video covering this topic:kzbin.info/www/bejne/qmKVimiei7mZgs0 My hypothesis is that they died out due to less efficient breeding strategy. They most likely gave birth to embryo-like joes yet had no pouch, so they were outcompeted by both marsupials and placentals.

[@nicholasmaude6906]

More than one genus is referred to as genera NOT genre.

[@cosmolewandowski7860]

Is it my imagination or is there a picture of a hyena blended into a tree branch one of these ancient mammals is seen sitting on?

[@chistinelane]

Which one?

[@beastmaster0934]

@@chistinelane 6:36 This one

[@donkeykong6426]

Nemegtbaatar is a interesting species that is extinct

[@BlackChrisAndersen]

the name of musik at 9:25 plis can enybodey tell me :) ?

[@TheFoshaMan]

No idea my man, try spotify

[@BlackChrisAndersen]

@@TheFoshaMan how is Spotify supposed to be better at searching for a song that i don't even know the name of just asking??. thanks for answering my message but you might as well not have done it at all

[@BlackChrisAndersen]

I found it it's from World of Warcraft battle for Azeroth. zuldazar soundtrack ;)

[@TheFoshaMan]

@@BlackChrisAndersen you're your own hero, and mine too, thanks man!

[@BlackChrisAndersen]

@@TheFoshaMan :) thank you

[@thomascorbett2936]

Are these some type of mammal ?

[@Engifarting456]

no theyre mollusks

[@justashark776]

@@Engifarting456 Idiot, they're clearly crustaceans

[@BigBoiFobbs2011]

​@@Engifarting456bruh

[@tirkentube]

so it's just a bunch of rats. gotcha.