I just want to say how glad I am that SciShow isn’t full of over-dramatic background music. It’s my pet peeve when watching non-fiction shows

@AlleenLoveHope

2 жыл бұрын

Same! I also appreciate that this channel presents info in an interesting manner without resorting to sensationalism.

@anyascelticcreations

2 жыл бұрын

Same

@oscarinacan

2 жыл бұрын

Man are you right. There's only a handful of copyright free songs that are constantly used and they are so annoying

@donhillsmanii5906

2 жыл бұрын

Dude. For realz

@leahc3357

2 жыл бұрын

Couldn’t agree more

I love learning. I had never heard of the big shark extinction event or the Guadalupian event.

@ancientswordrage

2 жыл бұрын

Same here. Glad I watched this episode!

Another theory that I've learned about regarding the Neanderthal extinction centers on their caloric intake requirements. From studying their bones, it has been estimated by scientists that they had a significantly higher muscle mass and metabolism, which then required a significantly higher caloric intake than the average homo sapiens. As a result, sapiens could survive with less food, which in colder periods (like the one where the Neanderthals disappeared from the fossil record) could easily make the difference over who survives and who doesn't. If you couple this with some of the other complementary theories about this extinction, it sadly starts to look like a recipe for disaster for the Neanderthal. 😞

@vasiliss.2426

2 жыл бұрын

Not really. When you don't have enough food, you do your best to find it. Australopithecus has done that. Australopithecus got extinct earlier.

@CleverMonster101

2 жыл бұрын

I have just written an essay on the extinction of Neanderthals and I really like the theory about climate change killing them off slowly and eventually with their smaller population size died out from a few smaller factors

@Dee-jp7ek

2 жыл бұрын

Another PBS Eons fan I see

@xanv8051

2 жыл бұрын

I think i saw this on a pbs eons

@alchemysaga3745

2 жыл бұрын

@@vasiliss.2426 Having a higher caloric demand means that you have a smaller grace period for finding food because you burn more calories even at rest. Even if you get food before you die, you could die before you manage to digest the food.

Another theory for Neanderthal extinction is the opposite of why Sapiens survived so well: social structures. Every place we've found Neanderthal fossils it tends to be small family groups, not entire tribes or nations of people. That doesn't just affect genetic diversity but also how much people can help each other and how many resources they can find and share.

@loke6664

2 жыл бұрын

That is certainly a possibility and we know that at least at the end the total number of Neanderthals in the world was very small. However, before that we are working with a relatively small number of fossils that have survived so there could have existed tribes further back. That far back, evidence for larger homo sapiens tribes are rather small too so I think it is a bit dangerous to be certain of how large their groups was. The strange 176 000 years old structures in the Bruniquel Cave is an oddity that seems to have been built by more then a small family. That can't of course be proven without reasonable doubt but the structures almost seems temple like in nature and the question is if that was a one time thing where several families built it for some reason or something else but there is a lot we don't know of these people. It is possible that if you go back a while there were a lot more of them around and that they slowly died out. We do know that the genetic diversity got worse and worse so the event that lead to extinction might very well have started far earlier and slowly lead to a few spread out families up to 45 000 years ago or so. We have figured out a lot about the Neanderthals lately. We have now clear evidence that at least a group of them buried their dead. We have pretty good evidence for them doing a couple of cave paintings. We know that they used fibers, maybe for rope or even clothes, we are not sure of that. We know they made jewelry and painted their bodies. Those are signs of social structures, the question is how advanced those structures were. Just in the last 5 years a lot of those evidence have popped up and the more we figure out, the closer they seems to have acted like our ancestors. In fact, 176 000 years ago we lack any evidence our forefathers built any structures even if they certainly might have done so. I don't think we have enough evidence for any theory right now, we have a 10 000 pieces puzzle but have just found a couple of pieces so far. The majority of our knowledge is from the last few thousands years. You might very well be right, many archaeologists thinks that there never been more then a few hundred thousands Neanderthals at the same time but the basis for that is pretty thin and might change as new finds pop up. What we do know is that they were not that different from us and it might just be a coin flip between them being extinct and us instead.

@ktx49

2 жыл бұрын

But this is a classic example of what came first, the chicken or the egg. Were they more susceptible to extinction because they had small social structures? Or did they evolve traits that constrained these societal structures(like possibly aggression, cultural based in-breeding, higher caloric demands, smaller pre frontal for planning etc)?

@anyascelticcreations

2 жыл бұрын

I must be more Neanderthal than most people then. Lol. I prefer small groups or being alone. But yes, it's difficult to survive without a tribe.

@davidmhh9977

2 жыл бұрын

Neanderthals, as a species, really are far more fascinating than they're truly given credit for. Regardless of how they went extinct, it still means that there was a species almost exactly like modern human but became extinct due to reasons so subtle, it's hard to even pinpoint the exact the cause. It really puts it into perspective how fragile we as a species. A few small changes like smaller tribal units, different tools, or even just more muscle mass to feed could have prevented all of humanities accomplishments from the agriculture revolution onward.

@bozomori2287

2 жыл бұрын

@@davidmhh9977 Believe me I am confused about them being considered a different species. We bred with them and their genes are spread wide across Europe and Asia, so wide that the people who bare them today are too different in looks to consider each others as equals subconsiously. I have a question, If the neanderthals are portrayed as fair skinned. And we homo sapines suddenly came out from Africa in quick waves, were we black and them white?

The latest theory about Neanderthals is pretty interesting. Apparently, given that Neanderthals were much more robust and stockier in average compared to us, that meant that their caloric ingest was slightly bigger for their survival. That explains why Neanderthals never really became that widespread because bigger groups were unable to cope with difficult conditions that were very common in those times. Also, they relied more in their physical condition than us for hunting because Neanderthal equipment was more suited for melee attacks than our equipment that was more suited for medium to long distance hunting. You combine all of those factors and you get a pretty reasonable and interesting theory. Source: one of the latest Eons episodes

@AlleenLoveHope

2 жыл бұрын

@@magiccloud3074 What evidence is there that Neanderthals were more intelligent?

@kylerBD

2 жыл бұрын

@@magiccloud3074 0 evidence exists that neanderthals were more intelligent than us. Infact most evidence shows the opposite.

@bozomori2287

2 жыл бұрын

Why are neanderthals not human yet we today are all humans yet wildly diverse in looks and habitats??

@bozomori2287

2 жыл бұрын

@@magiccloud3074 what does that mean? Are races and species the same thing?

@bozomori2287

2 жыл бұрын

@@magiccloud3074 As far as I remember, If living beings can give birth to healthy offsprings then it means they belong to the same species. (Neanderthals and Modern Humans bred very fine according to how spread out their genes are) This leads me to think Neandarthals are just a specific kind of homo sapiens, like say a race of people we cant help but notice they are more special than the rest of us because of geography culture and morphology. Think about Australian Aboriginals for example.

I wonder if the Permian mass extinction was so bad because global biodiversity hadn't fully recovered from the Guadalupian mass extinction that preceeded it.

@Wolfie54545

2 жыл бұрын

@Morgen Peschke I bet you are right. That explains a lot.

@YouTubePurgetheblackplague

2 жыл бұрын

It's from the comet that struck the great lakes ice sheet and the tsunami that took out the city of Atlantis. That UFO's and alien encounters are our true ancestors. Have you seen time machine where same species, but changed differently (one big and brutus, one thin and good lungs good climbing, and the telepath) eat the remaining like humans. Ancient buildings where seamless just like UFO ships that people have seen. With more O2 in the air then we had giant humans.

@daydreamer8662

2 жыл бұрын

@@KZreadPurgetheblackplague This makes total sense and I kick myself for not thinking of it first. However, it doesn't explain the platypus

@YouTubePurgetheblackplague

2 жыл бұрын

@@daydreamer8662 mad scientist that just had fun mixing mammal, dinosaur/bird, and reptile DNA. Australia had the remaining Dinosaurs and Dinosaur reptiles.

@nicholasfaber9695

Жыл бұрын

@@KZreadPurgetheblackplague you’re kidding right

I like that you provided less supported hypothesizes, while also explaining why they are less supported.

Graphics of the associated years of the extinctions would be helpful. Overall, this was really a cool topic and well presented. Enjoyed!

"Mysterious Shark Extinction" is my new band name.

wait, wait, wait... *don't* we know what happened to the sharks with the non-linear denticles? In mat-sciences, didn't they find that linear denticles make it harder for bacterial colonies/mats to form; thus making the "linear denticle pattern" a viable bio-form to emulate with material science for use in hospital surfaces, and so on?... i am susceptible to mis-remembering things, so perhaps i'm mistaken...

My mother has 2% Neanderthal in her and upon finding out our thought was, "That seems like a lot." Her ancestors were from Southern Europe. In contrast my father had none and his ancestors are from Northern Europe. What is the average % of Neanderthal in people alive today? That would be interesting to find out.

@BigPurpleCarrot

2 жыл бұрын

2% is the average

@helderlouro

2 жыл бұрын

I'm a western European and I have 2% Neanderthal DNA

@aftersexhighfives

2 жыл бұрын

There's a guy in South America who has 4% and that's considered high. I think 2% is the average if someone has it.

@davilathegreat

2 жыл бұрын

"Approximately 20 percent of Neanderthal DNA survives in modern humans however, a single human has an average of 2%-2.5% Neanderthal DNA overall with some countries and backgrounds having a maximum of 3% per human." -Wiki "Neanderthal genetics"

@davilathegreat

2 жыл бұрын

And there are also articles claiming some have 4%, but also that it might even be beneficial, like having space behind your wisdom teeth.

A paper in 2014 theorized that a species of Asian bison crossed the Bering land bridge during the last glacial maximum. It's population exploded and ate so much grass it helped drive other grazing megafauna to extinction in the last 30,000 years.

I'm always happy to learn ANYTHING new about sharks. 😊

For the megafauna extinction combination of climate change and isolations caused by humans over hunting in certain areas may have caused these species to be more vulnerable to resource competition with other megafauna, smaller and more adapted herbivores like deer and bison, as well as smaller gene pools may have led to their demise. Being a bigger mammal may make it harder for predators and the weather to kill you, but it means you’re a bigger target for humans, it takes longer for you to replenish your numbers due to longer gestation times which means low birth rates as well, and you need more food.

@malleableconcrete

2 жыл бұрын

The most robust way of explaining I've heard is that particular animals, notably megafauna, would be pushed into refugia environments during previous times of climate related stress where they were overall not numerous but able to survive comfortably enough to repopulate and reoccupy their former range when better conditions returned. Even if humans weren't the most efficient hunters at this point they might have been able to put enough pressure on these animals in their refugia, or outright destroy the refugia through other means, that it pushed them to extinction before conditions improved enough that would otherwise have been able to handle humans. Generally speaking I feel like the purely climate hypothesis for the Pleistocene extinctions just has too many holes in it to make much sense, some other problems not mentioned in this video are the relative (though not total) lack of extinctions for megafuana in Africa and the fact that there's a curious relationship between the extinctions and how long humans have existed in various environments. I.E, South Asia is the next most lightly hit part of the world after Africa and is also the place that's had the longest lasting human population, it seems to imply that the large animals in these places had enough time to adapt to human presence in a way that animals in places like Australia or the Americas simply did not. There's also the strange places where the last holdouts seemed to live in, notably islands like Wrangel island or St Paul's island for Woolly Mammoths and the Antilles for Ground Sloths. Presumably these locations should have been suffering from the same world wide climate changes as everywhere else in addition to the extra problems that the limited resources and migrations opportunities that islands afford compared to the mainland and yet its paradoxically the case that the animals in question lasted for thousands of years longer here than on the mainland. What's the difference you may ask? Firm evidence for the presence of humans in these places of course! Also I've heard some other controversies about climate extinctions with some scientists saying that assuming that larger animals should be particularly vulnerable to climate changes is not clear cut, larger animals often have the advantage in being able to migrate much further and can occupy some surprisingly marginal environments that at first glance seem like they shouldn't be able to support them regardless (ie, elephants and lions in the deserts of Namibia). Previous mass extinctions would still hit smaller animals but the Pleistocene ones really don't, and crucially they don't seem to have had much impact on marine or freshwater life which is highly unusual, even an animal as vulnerable as the Stellar's Sea Cow managed to make it into the industrial era. So its all pretty shaky.

@nunofoo8620

2 жыл бұрын

@@malleableconcrete I agree. I would add that the change in climate from a glacial to interglacial phase and vice-versa is definitely a big pressure on fauna and flora but the plistocene mega-fauna had survived these changes several times before the arrival of homo-sapiens (there were dozens of glacial to interglacial and vice-versa changes in the plistocene).

@reuireuiop0

2 жыл бұрын

Well said, though I would add that the onset of the Younger Dryas cool period, which either caused or greatly speeded up the pleistocene Mega-Fauna extinctions, was really exceptionally sudden. Climate Cooling usually is a slow process, but here we had a drop off several degrees C in a matter of decades. Already depleted fauna numbers may have had a hard time finding refuge, or get to adapt to quick changes in vegetation. The Clovis hunter people themselves disappeared as well in that time frame, though they may have adopted completely different lifestyles to survive the harde times.

@reuireuiop0

2 жыл бұрын

Plus, Mega-Fauna hunting humans may have had preferred certain species, either easier to catch or less likely to get wounded while hunting. Such preferences will have changed vegetation and complete ecosystems, as grazing, browsing and other influences on grass, scrub and tree growths is different for each herbivore species. Over hunting grass eating species will lead to more forest and scrubland, in which mammoths and other open field depending species have a hard time finding enough food to sustain their big bodies. Overkill of forest browsers will lead to dense growth, die back and fires, further endangering forest animals. Large hunters like Dire Wolves, Short Face Bears, Cave Lion and Sabre Tooth, need sufficient numbers of large beasts, or they will find it hard to chase down sufficient prey to keep up their numbers. Besides, those larger predrators have lower numbers, making it easier for humans to track them down and kill their offspring.

The megafauna mass extinction event 12k years ago coincides with the Younger Dryas period. (12,900-11,600 cal BP). That is, a sudden and extreme temperature change, which lasted approx 1300 years. A hypothesis gaining traction is that the end of the younger dryas was triggered by a comet impact over the northern hemisphere. The impact apparently caused the 2km thick glaciers covering Canada to rapidly melt. I mean rapidly. The scablands in northern USA were allegedly caused by huge flows of melt water, washing away the countryside and decimating the megafauna. Watch Randall Carlson on one of Joe Rogans podcasts, brilliant stuff, he has studied the scablands for years. Also podcasts with Graham Hancock, he ties in the comet theory. Also goes on to explain the effect the comet had on human civilisation around the Mediterranean at the time as the comet appears to have broken up and impacted numerous places across the northern hemisphere. A recenty discovered depression under the Greenland icecaps indicate an impact site which dates to that time.

Thanks scishow! The day this video went up I have been watching this channel for 9 years! It's been a pleasure watching the changes and growth this channel has made!

I’m always going to be sad that the glyptodonts died out. I wish I could have petted a giant armadillo.

I'm starting to think extinction is part of the planet's life cycle.

@meisteremm

2 жыл бұрын

Every system needs a reboot.

Thanks for all the informative videos all these years. I hope that your team and SciShow never goes extinct. Seasons greetings to all of you. ❤

"...at least as far as we know..." Thank you for this!

#4 So if the Guadalupian extinction is officially classified as the 6th mass extinction. Would that make the current one we’re causing the 7th?

@puggumpus

2 жыл бұрын

In a sence, yes

@MollyTheUkulele

2 жыл бұрын

Oof

Rose makes a great host! Insightful and interesting...!

Since I know you like to learn things, the name of the traps in China is pronounced "EEE- May- Shan". The three syllables are each individual words, and the first is the long "E", as in "cheese". " E Mei Shan" sounds like it means "single (or solitary) beautiful mountain", but I'd have to go look it up to be sure. Thanks for everything you teach me!

Nicely done! Fascinating to know of the many many people, places and animals that once existed.

Everything has multiple causes. There is always more than one factor when it comes to these things. They all line up just right (or wrong) and change happens. Such is life in many ways.

How will we be able to prevent another mass extinction in the future if we are living through one right now, given overpopulation and our dependence upon an industrial supply chain? We're toast.

@jfangm

2 жыл бұрын

It is impossible to prevent mass extinctions, and foolish to think humans are solely to blame. 99% of all species that have ever existed had already died out long before we ever came on the scene. This may sound callous, but adapt or die is the way nature works. Sometimes, keeping something alive just because you like it is more cruel than letting it die.

@jerrimcc6520

2 жыл бұрын

Thank you. I came looking for this, and was going to add it if I didn’t find that someone else already had.

@josepardo7097

10 ай бұрын

"Humans are a species, like millions of others, and I think it's dangerous to think otherwise." - Gary Larson (the far side)

This is probobly one of my favorite channels

I think you are underestimating the survival pressure of parasites on sharks. Possibly on other creatures as well. When a "decomposition" bacteria gains "a head start" by attacking the animal while still alive.

If it seems that the Sharks were effected based on their scales, i would say something like parasites. As if one style helped ward off something that could latch onto their sides, then that would be a "Quick" answer, assuming we could find something that latches on and feeds on sharks to some degree today.

@randybarnett2308

2 жыл бұрын

Today sharks are no better off than 19 million years ago, we harvest 100 million a year for fins alone, how long can that last?

@sandra.helianthus

2 жыл бұрын

Why would you want to find something feeding on sharks? Most shark species are near extinction today, too and none are a real threat (compared to "real" threats that kill thousands of people each year like cars, guns and more man made stuff).

@seregiel9541

2 жыл бұрын

@@sandra.helianthus I read it as finding an example of this potential parasitic relationship would help understand the issue, not that they wants it to happen/exist.

@sandra.helianthus

2 жыл бұрын

@@seregiel9541 one could read it that way, too, I suppose. Then I misunderstood. Thanks for your corrective suggestion! 🌻

Thanks! I loved the thorough presentation. I also liked that there was some pauses left in. So many sound like a 15 minute run on sentence.

Passenger Pigeon extinction impact will be large, as will the Locust'. Two major food resources for wildlife, gone in less than a couple hundred years. we have so little information what impacts our changes will push into the future, yet we are making these changes far too rapidly.

@eliharper6616

2 жыл бұрын

Seems mosquitos will soon top that list of unfathomable swarms wiped out in the name of progress It's a shame scientists and politicians put so much effort into climate change, tree planting, and invasive species control while bulldozers and trucks of pesticide destroy everything around them

@josepardo7097

10 ай бұрын

Bees.

Yay Rose!!! Keep up the good work!!

I have always theorized that other humans, including Neanderthals, didn’t form big enough groups, like towns, to have the depth of populations to survive negative occurrences, whether it be food shortages, danger, weather, and the many things that could cause the demise of a bunch of really small groups. No matter how many of the small groups existed, that size is always one step away from failure. Like individual families across the early US. There were many dead end settlements. We needed large groups to have the depth to survive.

My Guess: Sharknado 😀

@baomao7243

16 күн бұрын

Sharknado: The Prequel

I love that she mentioned the Ice Age characters 😊

That woman has a wonderful voice and delivery of her speech. Like!

Yes plenty to ponder on SciShow!

These discoveries are all so exciting. Imagine what can be accomplished the more we know.

Thank you, Rose. You're my favorite presenter here. Followed closely by Michael.

@cornbreadfedkirkpatrick9647

2 жыл бұрын

same here along with Reid

Thank you for not playing annoying music over your narration -- which ruins most science shows

I can't help but chuckle every time I hear dermal denticals

I've always thought Neanderthal extinction was an all-of-the-above thing, even way back before the idea of interbreeding was ever confirmed. Never even knew about the shark extinction! I always thought the disappearance of the megafauna was our fault. We do seem to have that effect, everywhere we go. The Guadalupian extinction event would make this one we're in the 7th mass extinction event, then.

6:13 a potential explanation could be that something caused the current of the water to become more extreme resulting in sharks with non-linear scales to struggle more so than prior to whatever caused the calamity in the first place.

@aquadark2291

2 жыл бұрын

My thought on this since it seemed to be global from what they said was that perchance something caused a shift in the density of the waters oceans. At least suddenly enough over time to not give the sharks a real chance at adaptation. Which would in turn cause a shift in the currents of the water.

@_kudos8093

2 жыл бұрын

@@aquadark2291 another thing to take into consideration is the earth's rotation, how it effects the flow of water, and what could have effected it if anything. This can be done and an nteresting man-made example would be the dam in china that literally slowed down the earth's rotation by approximately 6 seconds, probably ultimately resulting in a faster increase in the long run.

I wish you guys explored the theory of Neanderthals going extinct because they had tougher bodies, and were able to take down bigger prey without using ranged weapons. Therefore never having a necessity to adopt throwing spears and other primitive throwing weapons and starved themselves out.

@jfangm

2 жыл бұрын

They had throwing spears. There is even evidence they had better spears and spear-making techniques than Homo Sapiens, and that they taught those techniques to Homo Sapiens. It is utterly foolish to think they took down megafauna without thrown weapons.

@MadladMgeee

2 жыл бұрын

@Jason Mimiaga Wrong. They threw spears, but they did not use throwing spears, a spear thrower, spear throwing lever, or atlatl. Googling "Did neanderthals use throwing spears?" Will lead you to concrete evidence of this.

@jfangm

2 жыл бұрын

@@MadladMgeee No, I am not wrong. You said "they did not use throwing spears," not "they did not use spear-throwers;" a spear is naturally a throwing weapon, so if the Neanderthals had spears, they had throwing weapons. An atlatl is NOT required to throw a spear - they make it easier and more effective, but are not required. Unassisted spear throwing has been a thing for tens of millenia. Learn what words mean before opening your mouth.

This narrator has really improved her skills as she’s been on. Props to her!

@TheFourthWinchester

2 жыл бұрын

I agree. I used to hate her. Now I like her.

Fantastic video 👍🏿

I thought the mega-fauna mass extinction was now being attributed to the advent of grasses, with how quickly altered the landscape and available food because of various advantages it has over other plants. This reduced the available plant mass and sources that was available for the mega-fauna to eat. Even if the mega-fauna did try to adapt to eating grass, many of them were ill-suited to chewing grass because it edges it's leaves with silicate crystals which wore the teeth down faster than a normal lifespan would expect. Unless I'm thinking of a different mega-fauna mass extinction. I heard this on a documentary "How to Grow a Planet, pt. 3 'The Challenger' " (2012), and I don't remember the exact year range it occurred over.

The likely reason why Africa is the only continent where megafauna still remain is because that is where modern humans evolved and the megafauna there had adaptations to cope with human hunting. Megafauna in other parts of the world didn't evolve alongside humans, so didn't have those adaptations.

@josepardo7097

10 ай бұрын

Given the cosmic impact hypothesis, and that it supposedly hit the laurentide ice sheet somewhere in north America, and looking at the fact that Africa is on the opposite side of the planet, well.. you see what I'm getting at.

I love extinction. We wouldn't be here without it.

@josepha5885

2 жыл бұрын

Same for the dinosaurs. An extinction brought in and also took them out.

Really enjoy this presenter. Great job, great content.

Awesome. Thanks! 😀

Everytime South Africa gets mentioned in one of these episodes, I get all excited, it's nice seeing your home country get represented as a site with major scientific contributions to make lol

Always interesting.

If I'm not mistaken I thought neanderthals we're also homo sapiens. Everything I ever read about them always labeled them : homo sapien- neanderthal. Then there was homo sapien- modern. Which is us. Also neanderthal DNA can be found in modern humans. So they didn't quite go extinct completely.

@jfangm

2 жыл бұрын

You're close. It's Homo Sapien Neanderthalensis and Homo Sapien Sapiens. And yes, it is widely believed that the two werre subspecies of the same species. However, Neanderthal DNA is only found in those of European and Asian decent, and in VERY small quantities -

I'm really curious I would love to know if any studies have ever been done to see what the gestation time of a neanderthal was. Maybe their populations were lower because they had to carry their big robust babies much longer.

Do we know where Neanderthals evolved from? I've never read or heard of any theories & I think it would be interesting.

@kmcrafting4837

2 жыл бұрын

As of about 8 years ago when I got my MA in Anthropology the leading hypothesis was H. erectus -> H. heidelbergensis -> H. Neanderthalensis. Lots of debate on if the former two were distinct enough to be separate species. Currently heidelbergensis is classified as a subspecies of erectus. That’s the cliff notes version.

@hhiippiittyy

2 жыл бұрын

@@kmcrafting4837 I think I read that in Dawkins' "Ancestors Tale". Been a while. Great book.

@anyascelticcreations

2 жыл бұрын

@@kmcrafting4837 What an awesome subject to have a MA in! I love the education that I have. (Much less formal) But I would absolutely love to also have an education like yours!

@stephenballard3759

2 жыл бұрын

John, modern humans split from Neanderthals @ 380,000-450, 000 years ago, from our common ancestor H.Heidelbergensis. Our lineage stayed in Africa, possibly mixing with our very similar cousins here and there. Neanderthals became mostly separated from us and spread across Europe and Asia. There seems to be an area in the Middle East, around Israel, where our ranges both overlapped and ebbed and flowed, so some intemixing seems to have happened more or less perpetually. Over that next 400,000 years, though, we and they were more or less isolated from each other, though. The "Ice Age" began, and the glaciers would expand and contract as the climate cycled. The Neanderthals just lived there, hunting and migrating slowly, as the edges of the glaciers pushed north and south. The glacial cycles caused a very volatile climate in Africa, and the ancestors of modern humans were often separated by deserts, then reconnected 10,000 years, or whatever amount of time later, leading to diverse, but small, groups interbreeding. Finally, about 75,000 years ago, our lineage ALMOST went extinct, during a severe glacial maximum, which devastated much of Africa. Our populations shrank to as few as FIFTY, but as many as 2000 mated pairs of adults. This period marks the beginning of a rapid advance in technology, art, culture, and possibly language. The next time the glaciers retreated, the climate stablized to basically like today, with smaller periodic fluctuations. Our populations expanded rapidly, and now ice AND ocean-free areas allowed migration of modern humans out of Africa, and........ we met our cousins in Europe and Asia.

@jfangm

2 жыл бұрын

I think the most recent theory is that we evolved alongside them from a common ancestor as two subspecies of Homo Sapien.

Humans are doing a great job of trying to wipe out sharks today....for soup.

@property_rr1781

2 жыл бұрын

Good soup

@ianmacfarlane1241

2 жыл бұрын

@@property_rr1781 the planet needs sharks more than it needs weird soup. Besides there are dozens, if not hundreds of kinds of soup that people can enjoy without wiping out an entire group of animals. It's also beyond cruel] - cutting fins off before throwing them back to suffer an awful, slow death it's a tragedy.

This video was really good

Actually what you really aren't told is all large dinosaurs bones weren't strong enough to even support there own body weight. So what does this actually mean. Well it means that the force of gravity was much less then. Or bones didn't need to be as dense to support huge weights. A sudden instantaneous event most likely made them so heavy they collapsed and crushed themselves to death just from there own weight. What could do this. Well the introduction of the moon to our planet would do just that very thing.

I don't get why people still look for *one* specific cause , when it is so much more likely that multiple factors contribute to the matter.

Thanks guys

Bear Don’t Walk is rad

These damn hand movements might as well hand sign it all 😂

I believe I spotted a Neanderthal last week during a visit to NYC.

Nice video

I hit the notification bell but am not getting notified when you post.

I was taught in college that because we share a small % of dna and because that DNA is specifically Linked to fighting disease.. it wasn’t because of disease.

@MontananMusician

2 жыл бұрын

Wasn’t it because of food and because Neanderthals needed more calories?

@MontananMusician

2 жыл бұрын

Humans just outcompeted them because we required less energy to do more

@chriszettel6332

2 жыл бұрын

I thought the ginger gene came from neanderthal s??

Man I’m old!!! I remember when the dinosaurs died out 65 million years ago, now it’s 66.

@baomao7243

16 күн бұрын

Sounds like you’re soon to be extinct

I’d go with the disease hypothesis. Warfare is unlikely, in this period. And death by disease is pretty common.

@anyascelticcreations

2 жыл бұрын

Makes sense to me. War is so costly, especially if a population is already low. I don't think it would have made much sense for them to fight much. But disease does sound very likely. I also think that starvation is likely for a species that needs more calories to survive.

@cornbreadfedkirkpatrick9647

2 жыл бұрын

not for the whole thing

@jfangm

2 жыл бұрын

Warfare is likely regardless of the period.

Rose is back 🙂

Does the shark one have to be scale related? Couldn't it just be that the two types of shark groups with different scales split of from each other before and then later these groups evolved differently, which then was what might have killed the group? For example, if the extinct group evolved to take advantage of a niche that was suddenly not there anymore. Just seems weird that scales could kill so many shark species.

11:03 - ... Humans? ... Preventing Global Disasters? 😳🤣🤣 THAT'll be the day!!!

Crazy it's a 10,000,000:1 kill ratio between sharks and humans.

Doesn't the fact that we now know that humans arrived in North America thousands of years (maybe tens of thousands) earlier than previously thought disprove the "mega fauna went extinct when humans arrived" theory?

Ever since my professor told me the "th" in Neanderthal is pronounced more like a soft "t" and not a "th" as in the word "the," I find it really grates on me when I hear it pronounced "wrong."

9:15 Too bad the Guadalupian failed in the end 😞

Obviously the silurians ate a huge amount of shark fins soup 19millions years ago.

Shark scales and extinction... 3 things occur to me. 1) linear scales might generate less surface drag, allowing sharks with linear scales to get by with less food, or, having less drag would be faster and more able to get food. But why at this time and not before? 2) Geometric scales might allow life forms to grow more on the sharks' skin, sort of like bottom fouling on a boat, exacerbating the difference on drag, but again, why at this time and not before? I suppose maybe a new skin-fouling organism might have arisen at this time. 3) The difference was not directly related to the scales themselves, but to some other difference, not visible, between linear-scaled sharks and those with geometric scales. For example, perhaps a genetic difference between the two groups that made a difference in suceptability to a disease organism that arose at this time. Or, it could have been something else altogether.

@jfangm

2 жыл бұрын

Who's to say it didn't happen before?

@CAMacKenzie

2 жыл бұрын

@@jfangm Mention is made of an extinction event seen in the fossil record 19 million years ago, about 1/5 of the way through the Pliocene, in which about 90% of sharks went extinct, one group more than the other, and in which one group later recovered, while the other did not. The only other major extinction event mentioned for sharks, involving a much smaller percentage, was the big extinction event, involving generally all or most taxa, not just sharks, at the end of the Cretaceous. Fossil records are, necessarily, incomplete, and perhaps, at some future date, other substantial shark extinctions will be discovered, but for now...

@jfangm

2 жыл бұрын

@@CAMacKenzie What I'm saying is, we have no way of really knowing if other shark extinction events happened or not.

I have a theory for the sharks case. Just a theory. What if, something happened then and cleared the fossil records of that era? Maybe the records of those times was erased, not just for the sharks, but since the researchers are only looking at sharks, they see a gap. But its a gap caused by destruction of fossil records. The destruction didnt go deep enough, so it didnt destroy records before then, and the records after then were just left untouched since there wasn’t any destruction after that. So now, there is a gap. Maybe?

This lady is a good reader

The Guadelupian is truly the Thanksgiving of mass extinction events

"Shark contrast" xD

Personally, I blame the druids charm kiting the mammoths to extinction for the fat exp and expensive loot they dropped.

I watch Eons but I didn't know about the other masa extinction event or the shark extinction one.

... I squealed when we got to the ice age, because I recognize the museum that picture is from.

Didn't Oetzi have 10% Neanderthal DNA despite living far closer to us than them? That seems like interbreeding could have had a large impact. There was a huge amount of migrations of homo sapiens in the "late" stone age after all that could have further diluted their contribution.

@ValeriePallaoro

2 жыл бұрын

Wouldn't have been 10% .. that's a lot of DNA overlap

I’m still waiting for someone to bring back Wooly Mammoths.

Couldn't some sort of massive underwater volcanic event killed off the sharks, leaving the faster swimmers to filter out the chemicals better?

@daveasence8948

2 жыл бұрын

Thats a good theory

@Fermi_Consistency

2 жыл бұрын

I assume ocean acidification and lack of oxygen for such big creatures would be a problem. Also, wouldn't the cartilage start to disintegrate?

The most 11:43 minutes of knowledge I've ever received. Help us all...

She's really improving her presenting skills!

Oil, crabapples and mayonnaise. Rubbin it hard, then free apples with mayonnaise.

Was there a large radioactive event or change in underwater volcanic activity 19 million years ago?

Do we know if it was a comet or an asteroid that killed the dinosaurs? I've never heard somebody say comet for the KPG extinction before

Can you guys make a video about HeLa cells?

One Volcano interrupted and caused a mass extinction that nearly wiped out all life on the planet and you think that we have any impact. You can't stop extinctions they're a necessary part of the natural course of life on Earth.

"we are pretty sure a meteor hit the planet (or comet)? but it took years to come to that conclusion"

Are we presently going through a shark extinction? Shark fin soup!

05:55 Further proof that sharks are so smooth, extinction events just slide right off them

Linear striations would probably make those sharks harder to grab onto. Didn’t the megalodon show up around that period?

Koalas in Tasmania: great habitat, few humans and little competition but … they’re gone. Why?🤔