just over 10,000 years ago huge woolly mammoths woolly rhinos giant ground sloths direwolves and even giant armadillos roamed the land and now they're gone so where do they go in this video I'm going to talk about the evolution and Extinction of these giant megap that lived in the pene epoch from about 2.6 million years ago until about 11,000 700 years ago and I'll talk about some major examples of these megap like those I just mentioned as well as what we think made them disappear so first what are the megap well megap just refers to kind of huge animals and typically when we're talking about the P toine meapa we're talking about huge animals that roamed Earth during the P toine Epoch which was the one just before our current holine Epoch which like I said went from 2.6 million years ago till about 11,000 years ago and from what I've seen the size requirement or criteria to be classified as megap is that the animal just has to be over 45 kg or about 100 lb so yeah we're technically meapa I guess of the holos scene which is pretty funny well I guess not our babies but our adults um but I guess that's not true of any babies okay I'm getting off topic anyway what I want to answer in this video is kind of what were they where did they live how they live and why and how did they go extinct so first to set the scene the place to scene Epoch is known for well being an Ice Age the most recent Ice Age with very distinctive interglacial Cycles what this means is just repeated up and down uh fluctuations in temperature due to repeated periodic changes in Earth's astronomical cycle so it's orbit it's wobble it's til um and so because these astronomical factors of Earth change periodically on a you know predictable periodicity it was cyclic change up and down and essentially what's important to note about the P toine Ice Age is that the ice age is kind of the whole time period uh that these interglacials have been going on so from around 2.6 million years ago to today really but this last cool period uh or the last time that glaciers were at a maximum is what we call the last glacial maximum or lgm so if you see lgm throughout this you know video that's what that means essentially um right after the lgm we started seeing warming in this bulling alloid event sorry if I'm mispronouncing that and this was the beginning of interglacial warming you know coming out of the cool cycle moving into the warmer cycle which eventually led us into our current Epoch the holos scene but what's interesting about this interglacial warming is it started to warm and then it dropped dramatically and this cooling this rapid cooling event that we call the younger drus cooling uh the younger drus is just named for um plant a flower I think something dest or dest is the genus I don't know anyway it just marked colder conditions colder climates because that flower likes to live in colder climates it doesn't necessarily mean that conditions were drier the dry part of that word don't read too much into that um but things got cooler during this younger drus time frame or cooling event and this younger drus is the time frame within which the meapa went extinct or most of them so was this rapid cooling event the cause of their Extinction maybe but maybe not as hinted by this picture human over hunting may have played a role but I'll get into the caveats with both of those hypotheses later in the video and suggest some other hypotheses that people have also proposed and kind of the evidence and lack thereof for all of these things first though let's talk about what the megap were some major examples at least and where they lived how they lived how they evolved stuff like that megap at this time included a variety of mammals much larger than those today well some of them larger than those today some of them kind of similar sizes in any case they were you know remarkable for their huge sizes notable examples include mammoths and mastadons as you know in these pictures as well as on my hat which you know I had to wear this hat for this video Sabertooth cats sometimes called saber-tooth tigers but they're not Tigers they were big cats but no Tigers uh necessarily but these guys are also really you know popular pretty much picture the Ice Age movies and you know we've got the mega uh giant ground Sloss obviously Sid of course um but probably a little bigger um giant ground Sloss were freaking huge uh megatherium it's the genus name we'll talk about that later giant armadillos or glyptodon again the genus these guys are I think my favorite um who knew there were giant armadillos these are also in Ice Age I looked that up they they were minor characters I wish they were bigger the Giant short-faced bearss woolly rhinos which you know I think should have been a bigger thing I I didn't even know about woolly rhinos till researching for this video so you know let's make that more not that's like one adorable also terrifying but really cool and the direwolves which I've always known for obviously the place to scene I didn't know however that they were also a fictional thing associated with Game of Thrones or something I don't know I haven't watched it I know I I don't like to commit to very long series because then I spend too much time binging things anyway I don't know if you guys know of this thing but uh they were real they lived in the BL to scene um so yeah or at least I don't know if the fictional thing was based on the real one or not but anyway they were real but anyway let's take a minute with each of these groups and kind of go through how they got to where they were and how they lived so first starting with mammoths and kind of elephants in general the earliest known boset or the order of elephants the big group that includes elephants mammoths Etc was this kind of small Pig sized herbivore in Africa around 60 million years ago so long before the place to scene kind of right after the kpg extinction event that took out the dinosaurs allowing mammals to start growing larger diversifying Etc then much later around 37 to 30 million years ago came fiomia and morum I'm going to go with that um which are two uh Genera genuses that lived in Northern African swamps and woodlands and the moer ethereum had a flexible upper lip and extended canines that may have been rudimentary tusks but they spent most of their time half submerged in water like hippos or more like hippos at least than elephants whereas fiomia were more elephant like wing half a ton and eating terrestrial rather than Marine vegetation finally gers appeared around 28 to 30 million years ago and this group is the one that eventually broke out and led to mastadons Mamas and eventually modern elephants they were widespread across lowlands of North America Africa and Eurasia from around 15 to 5 million years ago and yes modern elephants and mammoth did coexist it's not that modern elephants evolved from Mammoth which you know I probably should have known that didn't know that I just kind of assumed you know Mammoth and elephants whatever but actually they both had a common ancestor that kind of broke off into each group and it's just that elephants survived to the present and Mammoth did not Mammoth and mastadons are place to seen megaphon examples evolved from gers around 23 million years ago for mastadons so a little bit older of an origin for mastadons and 6 million years ago for Mammoth so relatively more recent as shown in this timeline then they both went extinct at the end of the P toine from around 12 to 10,000 years ago during that younger dras time I do have this range here rather than a specific year that they went extinct because and you'll see this throughout out the video with other megap as well because one these extinctions were relatively protracted both spacially and temporally some species went extinct in this region at this time then others went extinct at this region in this time overall the extinctions took place during the younger dras and all the megap the major groups were extinct by the end of the pine however it was kind of over time and in different places at different times uh which you know later we'll talk about what that means in terms of causes um but in any case this is one reason that I don't have a specific year here also another thing to keep in mind cuz I make a lot of videos about mass extinction events in other videos when I talk about oh everything went extinct around 250 million years ago I don't have a range there because when it comes to 250 million years ago we're talking over a range of you know plus or minus 1 to five million years depending on the extinction event some Extinction events lasted over 10 million years so it depends on the extinction event um but they don't happen in one day so remember that when I say 12 to 10,000 years ago that range is is seems like a long time but it's relatively rapid for mass extinctions so anyway that's why it's a range not one particular year also notice that there is a dotted line on the mammoth timeline over here on my geologic time scale of when these things lived that's because mammoths largely went extinct at the anger dras by the end of the pla scene however some continued into the Hol scene as we figured out later uh isolated on a specific Island and they actually became like small because of this isolation anyway I won't get into this now I think I talked about this in one of my videos if I remember which one that is I'll link it to the top right um but I might make a whole future video about those so anyway that's just one group that only survived because they were isolated on this island for the most part on most major continents mammoths were effectively extinct by the end of the P to scene why well we think it was mainly due to human hunting again this also you know makes more sense with the relative protracted nature of these extinctions humans arrived over here blank when extinct humans then arrived over here blank when extinct this kind of pattern that we see in the rock record um but I'll talk more about that later and kind of the caveats with that now moving to Smilodon the genus of saber-tooth cats that we love so much these massive terrifying Predators with terrifying teeth belong to the extinct sub family maera Don you know I don't know if anybody actually knows how to pronounce these anyway this sub family lived from the neae right before the place to scene till the end of the PTO scene when the gene is Smilodon done when extinct and based on their fossil record saber-tooth cats were more robustly built than any extent or living cats with well-developed for liims and obviously they're exceptionally long upper can9 teeth the largest species got up to about 450 kg or 1,000 lb they hunted large herbivores like bison and camels very similar I think to like lions and other big cats today and they likely lived in closed habitats like forests or bush with cover for ambushing prey from what I've read we don't actually quite know yet whether they lived in hunted more in Prides like lions or were more solitary like tigers we're not actually quite sure um and I don't know if we'll ever figure that out fully but obviously there's ways of looking at the fossil record to see whether they were grouped or not um but maybe we'll figure that out at some point in any case Smilodon died out with most of the other American meapa around 12 th000 to 10,000 years ago like we talked about with Mammoth mastadons and likely their Extinction rather than due to over hunting was likely due to the loss of their prey due to human over hunting their prey as well as climatic changes uh associated with the youngker dryest cooling so their Extinction was probably due to both climate and human activity next we have giant ground Sloss or the genus megatherium megatherium is such a good name for such a like huge megap anyway these guys lived in South America from around 5 million years ago so a bit before the pene up until the end of the plene and the extinctions of megatherium coincided with that of other mammal megap which followed the first arrival of humans in the Americas therefore hunting likely played a role in their Extinction as well next we have glyptodon the Giant armadillo these guys lived from about 5.3 million years ago till around the end of the place to scene they were part of a sub family gPad Don which lived from all the way back into the Paleo Gene up until their last genus the glyptodon went extinct and these are my favorite because they're so impressive in terms of their size they got up to 3.3 M or 11 ft long and 2,000 kg or almost 4500 lb pounds which is absolutely insane clipon was one of many South American megap that got to insane sizes like the giant ground sloth that we just talked about megatherium as well as nunget which are an extinct group of ulates that lived during the pine also classified as megap but I didn't list in the notable examples just because they're they don't really have any like living relatives that resemble them that well they're kind of like I don't know giant camels I don't know but really insane and glip toon in terms of how it lived what it ate it ate a mixed diet of grasses and other plants and their armor protected them from predators like Smilodon or saber-tooth cats protoy large canids arcum which were Central and South American short-faced bearss there were other short face bears and other regions that I'll talk about in a couple slides and obviously humans and like we have seen with all of the other megap glip it on when extinct at the end of the place to scene around 12,000 to 10,000 years ago moving to the short face Bears we had arcadis the largest genus of these bears that evolved around 2.5 million years ago and got up to 3.4 M or 11 ft tall on their hind legs and about 1,000 kg or 2,000 lb these Bears lived in temperate open Woodlands of North America and hunted herbivores such as deer camelids and tapier and like all the other meapa they went extinct to the end of the place to scene around 12 to 10,000 years ago likely due to a mixture of things one climate two probably some loss of prey from Human hunting and three competition with modern Bears next we have woolly rhinos which are an extinct species of rhino that lived in in Northern Eurasia from about 1.8 million years ago so kind of in the middle of the place to scene until about 14,000 years ago and I'll get to why that's not at the end of the place scene in a second they fed mainly on herbaceous plants and their long thick hair like the woly mammoth allowed them to survive in extreme cold harsh mamma step conditions the mam step by the way if you don't know is just kind of an environment or ecosystem that was characterized by the environments that Mammoth both lived in and maintain Mammoth kind of had this unique ability as well as other megap to clear you know forests and strubs and and create and maintain these grasslands by trampling down trees and keeping things trampled and smashed down so that grass could grow and and then grazers would come and live in this ecosystem and everything would kind of you know create this this grassland ecosystem that was called the mamama step so that's what uh this is referring to importantly the woolly rhinos unlike many other meapa went extinct around 14,000 years ago likely due to the brief rapid warming event that we talked about earlier which occurred just before the younger dras this was the interglacial warming from around 14,000 to around 12.9 th000 years ago just before the anger gas cooling that occurred from around 12.9 th000 years ago to 11.7 th000 years ago which marked the younger dras period this warming would have caused increased precipitation in snowfall which transformed their low growing grass and Herb habitat into shrubs and trees and this just well restricted their livable habitat until they went extinct however it's important to note that this warming event which precedes the younger dras which then marks the period that most of the megap went extinct may have played a role in other megap extinctions as well for example the Dire Wolf a large extinct canine is thought to have become very restricted in range around 13,000 years ago nearing the end of that warming event and then gone extinct right after in the end of the P scene during the yadas so it's likely that the warming you know was the first kind of thing that may have restricted the ranges of these megap given their adaptations to cold climates and then once colder conditions came back during the younger drest one you know the cooling was relatively rapid so that was difficult because they had all just migrated to cooler climatic uh you know ranges due to the warming event that then when the rapid cooling came it would have been really devastating if they couldn't handle that cold of conditions and two by the time the cooling came and they could expand again in range humans had by then taken over a lot of the regions they used to roam and obviously as they were walking right into the now human inhabited environments they were walking right into their predator's home so we've talked about climate and human hunting and competition with other modern species as causes for these extinctions but what exactly caused the extinctions of each of these groups specifically well one thing you may have noticed going through these different species or Genera on this list of megap is that most of these were large orborous mammals that lived in the Americas well the timing of human arrival in the Americas coincides pretty nicely with the extinctions of these American megap so that leads one to believe that at least some of these groups were likely if not you know totally extinguished by at least restricted by the over hunting of their individuals by humans so for Mammoth and mastadons it was likely a mixture of both rapid climate change and hunting and or other human activities remember hunting is not the only thing that likely led to them becoming restricted and killed off also we introduce diseases new types of diseases invasive species habitat alteration fragmentation and destruction we use up a lot of land we change the way that it's used the way that it's fragmented the way that it's distributed what's growing there Etc so a lot of these human activities not just hunting is kind of wrapped up in this one idea of like the over hunting hypothesis but really it's all these human things that we do not just hunting and then for groups like Smilodon the saber-tooth cats it was likely mostly loss of prey from both climate change and hunting for giant grounds loss it was probably both climate change and hunting and all the other human things same thing which giant armadillos our friend the gped on and then loss of pre climate change and competition with modern bear species for the giant short-faced bears woolly rhinos are unique and then it was probably mainly climate change because their Extinction preceded the younger dras it was during that warming event just before at least based on our current fossil record of these species they may have continued on into the younger dras but it seems that they were at least extremely restricted by the beginning of the younger dras due to the warming and then the direwolf like saber-tooth cats and bears was probably loss of prey climate change and competition so if we want to invoke the younger dras climate change or rapid cooling as one of these Extinction causes what actually caused this rapid cooling event what caused us to go from this interglacial warming drop back into Cooling and then back into interglacial warming why didn't the interglacial keep warming well there are hypotheses for what caused the cool in anywhere from meteor impacts to volcanism to a shutdown of the ocean conveyor or circulation belt but I talk about that in my next video over the younger dest Cooling and what caused it it may be out by the time you're watching it but if it's not yet or if it's members only it will eventually be out for everybody so don't worry about that just wait a couple of weeks but before you go if you are interested in meapa or any life that was Mega siiz you you probably also love dinosaurs and on my channel I love to educate about dinosaurs but instead of just listening to a lecture or reading a book you might want to learn in a more fun engaging kind of way and I happen to know about a really really exciting game coming out called Dino survival the creator of this game David Hills has worked really hard to make this game not just random Dino facts but really educate on how these dinosaurs lived in terms of their environment and their diet and it really kind of connects all the dinosaur species together and how they lived in ecosystems relying on one another which I find really really fun so far the final version of this card game is not officially out yet for purchase however you can support the kickstarter for this game right now at the link in my pinned comment below or I'll also put it in the description for this video and if you do support the kickstarter you can get a 25% off the game with guaranteed fulfillment after successful Kickstarter so I highly encourage you to go check that out I've played the early version or the pre-print version of the game it's really fun and David has been really accepting of my feedback and has made all the changes that I've suggested so I highly recommend great game and great Creator amazing thing to support if you have kids that love dinosaurs highly recommend it's like any age I feel like can enjoy this game uh so yeah go check that out and with that I will see you guys in the next video bye