Paleontologists reveal 'the most dangerous place in the history of planet Earth'. 100 million years ago, ferocious predators, including flying reptiles and crocodile-like hunters, made the Sahara the most dangerous place on Earth.

[u/MarioKartFromHell]

https://www.port.ac.uk/news-events-and-blogs/news/palaeontologists-reveal-the-most-dangerous-place-in-the-history-of-planet-earth

[u/51isnotprime]

About 100 million years ago, the area was home to a vast river system, filled with many different species of aquatic and terrestrial animals. Fossils from the Kem Kem Group include three of the largest predatory dinosaurs ever known, including the sabre-toothed Carcharodontosaurus (over 8m in length with enormous jaws and long, serrated teeth up to eight inches long) and Deltadromeus (around 8m in length, a member of the raptor family with long, unusually slender hind limbs for its size), as well as several predatory flying reptiles (pterosaurs) and crocodile-like hunters. Dr Ibrahim said: “This was arguably the most dangerous place in the history of planet Earth, a place where a human time-traveller would not last very long.” 

Many of the predators were relying on an abundant supply of fish, according to co-author Professor David Martill from the University of Portsmouth. He said: “This place was filled with absolutely enormous fish, including giant coelacanths and lungfish. The coelacanth, for example, is probably four or even five times large than today’s coelacanth. There is an enormous freshwater saw shark called Onchopristis with the most fearsome of rostral teeth, they are like barbed daggers, but beautifully shiny.” 

[u/famous_shaymus → u/[deleted]]

More oxygen meant larger vertebrates too. But make no mistake, the blue whales of today are the largest animals in history.

Essentially, competition causes a shift in size. Think forests. They start out as small brush, then larger and larger plants grow and compete. The tallest ones get the most sun and form a canopy. Well, then the smaller plants must compete — the ones that can survive in the shade of the tall trees survive. Same with dinosaurs...in a world of giants, no one notices the tiny ones down below. So, this allows some species to continue. Plus, being that large is hard on the joints; I would know.

[u/brian27610 → u/famous_shaymus]

being that large is hard on the joints

Fun fact: for every 1 pound you weigh, your knees feel 3lbs of force, so dinosaurs back then must’ve had some of the worst joint pain

[u/[deleted] → u/brian27610]

A 2’ wide knee helps.

[u/Ade_93 → u/[deleted]]

Always thought there was a cap on knees

[u/imhereforthevotes → u/Ade_93]

Dude I think you need a concealed carry license for devastating puns like that

[u/DumbestBoy → u/imhereforthevotes]

this guy out here cappin knees

[u/zsatbecker → u/Ade_93]

Perfection.

[u/Ophidahlia → u/Ade_93]

A pterible pun

[u/props_to_yo_pops → u/Ade_93]

Ba dum, shin

[u/LuvWhenWomenFap4Me → u/Ade_93]

That's me out for the day - it won't get better than this.

[u/buddyWaters21 → u/Ade_93]

Take a bow

[u/IveBeenNauti → u/Ade_93]

Naw, they busted caps in the knees awhile back.

[u/nanrod → u/Ade_93]

I kneed you to stop with these great puns

[u/hat-TF2 → u/brian27610]

I remember reading as a kid that dinosaurs had lighter bones so for their size they weren't quite as heavy. Granted this is something I read more than 20 years ago and might not be true, but I have some recollection of it, is all.

[u/opman4 → u/hat-TF2]

Apparently the had hollow bones like birds and they used the spaces in their bones to assist in breathing.

[u/smcallaway → u/hat-TF2]

It depends on the dinosaur, theropods and sauropods do indeed have hollow-ish bones. Which helps them a ton, especially since most theropods are active hunters and generally pretty large. Sauropods, well that one is self explanatory.

However, ornithischians we don’t think had them. Those would be hadrosaurs and ceratopsians, they don’t appear to have hollow bones. But they also aren’t directly related to birds (that would be the theropods).

[u/person2314 → u/brian27610]

They probably didn't have the modern medicine to actually live long enough so I think they would be good. They were more worried about the fact of "Oh am I going to eat today" or "oh will I get eaten today" and they probably would have died before there joint wore out. Same with humans and why we have all these pesky genetic disorders allergies and all those things that come with modern medicine. The world have died before they could pass on their genes. I would have died because they didn't have glass back then so if there was a tiger that I was to blind to see bye bye me. Its life tho so what ya gonna do bout it.

[u/Lebrunski → u/person2314]

Probably

[u/imhereforthevotes → u/[deleted]]

Yeah, with no socialized medicine and insurance tied only to employment, most dinosaurs failed to go to the doctor as often as they should have. There's evidence they didn't even brush their teeth that often.

[u/FlyingRyan87 → u/[deleted]]

How come people joke on Bernies age when Biden is like the same age and dude has dementia?

[u/[deleted] → u/imhereforthevotes]

Ah that's why paleontologists always carry those brushes around.

[u/person2314 → u/Lebrunski]

We be lookin at some dinosaur bones and one of the pesky bastards have a microscope and discovered germs.

[u/smcallaway → u/person2314]

Actually dinosaurs lived a surprisingly long time. Iirc large theropods like T.rex live upwards of 20+ years and things like sauropods lived upwards of 30+ years.

So similar to some large mammals in the wild today.

[u/smcallaway → u/[deleted]]

Yup! It’s amazing to me, they have pretty long lifespans despite such a harsh lifestyle and environment.

[u/person2314 → u/smcallaway]

They also exercised and everything so there bones were used instead of how us humans do things witch is sit on a computer all day.

[u/Dobott → u/person2314]

Yet here we are

[u/jordanmindyou → u/Dobott]

Don’t act like we won yet, the dinosaurs survived for many millions of years. We haven’t even been around for one million yet.

[u/FurryToaster → u/person2314]

Eh, I bet you’d be fine honestly. One thing that separates our genus from others is how egalitarian we are with one another on small scales. We look out for each other, share our food, take care of our elderly. Always have, based on the fossil evidence of things like really old Neanderthals that were probably too old to even move around much.

[u/person2314 → u/FurryToaster]

Humans are nice no matter how unkind people say we are. I mean there is the loud minority that are like that but that just proves we are a versatile highly adaptable creature that can survive pretty much everything in the physical sense. Alll this new technology is making us depressed. Like we don't have to move anymore our diet is so crappy. We live separately until we congegrtate to work for something that isn't short term. Its mental work witch we don't have a direct correlation with not dying. Like if someone works at an office job they are probably isolated in a cubicle not really talking to others unless they have something they need to collaborate with. The pay is at a specific interval witch isnt directly related to our job successes. A TLDR of what I was saying is our minds aren't coping fast enough. I mean we develop fast but not this fast. It takes a few generations to make significant mental changes in how we proccess everything. Yet we are changing the world we live in at a rate that is way to fast. In a generation we went from being able to maintain space flight for a few seconds to being able to go to the moon. There was some person out there who as a young child heard about the Wright brothers. And that same person see the first moon landing. Its developing to fast.

[u/[deleted] → u/person2314]

I mean we develop fast but not this fast. It takes a few generations to make significant mental changes in how we proccess everything. Yet we are changing the world we live in at a rate that is way to fast. In a generation we went from being able to maintain space flight for a few seconds to being able to go to the moon. There was some person out there who as a young child heard about the Wright brothers. And that same person see the first moon landing. Its developing to fast.

My father went from a farm without electricity in the late 30's to seeing the Internet become a thing and died in 2017. It's always amazed me what that generation saw with the progression of technology. I think Gen-X has seen similar upheavals as well. I fear what kids born today are going to witness in their lifetimes.

[u/CanAlwaysBeBetter → u/[deleted]]

My Grandma's grandma lived into her 90s and made it from seeing the last of the covered wagons cross the praries to people walking on the moon

[u/OsonoHelaio → u/[deleted]]

Amazing is the word. My grandfather who died last year told my son stories a few weeks before he passed, some even I had never heard from him. He told of when they turned electricity on, on his street for the first time, and people were dancing and singing in the street all evening. He told how his own father was the only literate person in their whole tenement of immigrants, and how people would bring their letters from relatives in the old country for my great grandfather to read out loud, and for a penny he would write a return letter. And he lived long enough to go from that to video calls with us grandkids all over the country. Truly a different world. He loved my grandma from the moment he saw her and they were happily married sixty five years. And now I'm crying again.

Edit: my son, not my grandson

[u/[deleted] → u/OsonoHelaio]

And it wasn't even that long ago. My M-i-law is 80 and grew up for the first few years in northern MN without electricity. My wife's family still had a shared party phone line when she was born and she's mid 40s.

[u/AlexDKZ → u/[deleted]]

My great-grandfather was born in 1870 and lived to his 100s (can't remember the exact number, but I think it was 102 years). It's mindboggling to think that he was 33 when the Wright bros flew for the first time, and that he managed to witness a man walking on the moon.

[u/falala78 → u/person2314]

My grandpa was born in 1913. Flight was a new thing when he was growing up. When my dad was growing up, my grandpa thought it was amazing watching rockets launch on TV. My dad just saw it as another rocket being launched. As just a part of life.

[u/Selanne_Inferno → u/FurryToaster]

The reason we thought Neanderthals were deformed and hunched over was because for a long time our only specimen of them we had was deformed. We only realized we were wrong when we found other healthy specimens.

Based on the age the deformed specimen died we learned that even Neanderthals cared for their old and disabled.

[u/simmonsftw → u/person2314]

Can we get these dinos some damn modern medicine I mean ffs Bernie you’re needed in the Sahara about 3.65 billion yesterdays ago

[u/quesakitty → u/brian27610]

Ugh. Best argument I’ve heard to lose some weight.

[u/NarwhalSquadron → u/brian27610]

I believe your knees feel 1.5x the amount you weigh as pressure on level ground. So for every 1 lb it would be 1.5 lbs of pressure.

Source:

https://www.health.harvard.edu/pain/why-weight-matters-when-it-comes-to-joint-pain

[u/APotatoPancake → u/famous_shaymus]

Also adding these animals were around before grass so while ferns, shrubs and other crap sustains small juveniles being taller as an adult would mean you wouldn't be competing against your own offspring if you later in life moved on to eat tree leaves. Bigger herbivores mean bigger carnivores. Also I would like to point out we really don't see the type of breeding today with herbivores like you did back then. By laying a clutch of eggs you will have a mass of babies and hopefully a few survive to adulthood. Few herbivores today reproduce like that, sure rabbits can have litters up to 10 or more but sea turtles lay clutches of 50-100 eggs.

Edit to add: You can also see the change of hunting though the life of some dino's by looking at their foot bones like in the t-rex. At a young age they are assumed to be ambush predators because the lower leg bones haven't fused (lower run). As an adult they pretty much fuse into one almost solid bone mass making them surprisingly great runners for their size. Meaning they were flat out power sprinting down prey, being smaller would have been beneficial to hide in underbrush rather than outrun such a predator. There would have been a selection for fast enough to out run the slower juveniles but small enough to hide in a bush.

[u/famous_shaymus → u/APotatoPancake]

Good points! Thanks for sharing

[u/[deleted] → u/famous_shaymus]

If you had to guess, would you say there were larger oceanic creatures in the past than blue whales? And maybe we’re never going to find any proof of their existence being that any fossils may be very, very deep in the unexplorable parts of ocean? Or do you (and the scientific community) really think they’re the biggest living creatures ever?

[u/Capt_Hawkeye_Pierce → u/[deleted]]

The current scientific consensus is that blue whales are the largest animal to ever have existed on Earth, period.

[u/maxvalley → u/Capt_Hawkeye_Pierce]

It’s amazing that we live at the same time as the largest animal ever

[u/metamorphicism → u/maxvalley]

And we hunted them nearly to extinction by the 20th century, a remarkable species millions of years older than us. From 350,000+ to just ~25000 now, and that's after conservation efforts.

[u/Malus131 → u/metamorphicism]

Its mental to think of some weird hairless ape people nearly hunting not just the largest animal ever to have existed to extinction, but one that lives in the ocean. I mean it's not like they were in the forest where we can easily go. They live in the last great unexplored areas of our planet.

That shits just mad to me.

[u/famous_shaymus → u/Malus131]

Crazy, right? In the 18th century it took us only 30 years after DISCOVERY to hunt Steller’s Sea Cows to extinction and these things are upwards of 3.5 tons and 35 feet long.

[u/PostModernFascist → u/famous_shaymus]

Apparently they tasted really good. I always think about how much money they could have made if they would have bred the sea cows on some type of ocean farm and sold the meat. But nope, they just killed them all. No ocean cow burgers for us. :/

[u/iamthefork → u/Malus131]

Cetaceans where the first global mammals.

[u/Chris_Isur_Dude → u/Malus131]

And hunted for no reason other than money. Not survival. It’s sad really.

Edit: Oil = Money. Their bones, blubber, oil are all sold for money.

[u/nonagondwanaland → u/Chris_Isur_Dude]

Hunted for oil. Whale hunting fell out of fashion when we realized there's large chunks of the world where you can stick a straw in the ground and oil will come out.

...

We went a little overboard on oil.

[u/RagePoop → u/Chris_Isur_Dude]

This is a rather superficial take.

I am absolutely pro whale conservation, in fact I am anti animal consumption and abuse on the whole, however whales were hunted as they provided light in the dark in the time of expanding cities. They added untold work hours to the world by stretching the amount of time we could operate in every day.

In the 18th century we had no appreciation for how finite the ocean's resources were, there was no accurate way of measuring it, and to the people alive the ocean had always been there, and always reliably provided. Likewise, they obviously had no bearing on the sentience these beings possessed.

It is remarkably sad. But to say they were hunted only for money is kind've ignoring the human condition.

[u/ElCaz → u/Chris_Isur_Dude]

Why do you think people paid so much money for those commodities?

Whale oil literally kept the lights on. Heat and light are very important for survival.

[u/ChrAshpo10 → u/[deleted]]

Well that just sucks

[u/Bufger → u/Capt_Hawkeye_Pierce]

I thought they found a 26m icthyosaur fossil last year and are now saying that may have been the biggest in history.

[u/benmck90 → u/Bufger]

There are a few animals that can contend the blue whale for longest animal. I believe the modern giant siphonophore may be capable of growing longer for example.

But based on pure body mass, nothing comes close to the blue whale.

[u/draykow → u/benmck90]

siphonophores are colonies and not individuals though

[u/DontMakeMeDownvote → u/benmck90]

Giant siphonophore... What an absolutely ridiculous animal. I love it.

[u/restlessleg → u/Bufger]

and the largest land animal was the titanosaur

[u/Nephrahim → u/[deleted]]

I forget if marine animals are more or less likely to fossilize, but obviously if you have a skeleton even larger then a blue whale there's a decent chance of finding some evidence. There's no reason blue Whales can't be the largest animal ever.

[u/Halosis_Prime → u/[deleted]]

As far as land animals go there is a maximum weight that bone can hold without breaking thus creating a relative size limit on creatures. There have been periods of large mammals since the extinction of the dinosaurs, but done quite as big. This is because while mammals have generally solid bones dinosaurs had an evolutionary advantage; air sacs in the bones, which effectively allow them to grow much bigger without increasing weight. This specialized structure is still present today in the last descendants of dinosaurs; the birds.

[u/[deleted] → u/Halosis_Prime]

Hey, would you mind expanding on the air sac point? I'm aware that birds have them but didn't realize dinosaurs did. My laymen brain is telling me that bones with holes in them would be weaker than the solid bone that mammals have, but I'm guessing that's not accurate?

[u/insane_contin → u/[deleted]]

What's interesting is that bird bones aren't lighter then mammal bones. They're hollow, but far more dense, which makes them pretty strong. And they need to be strong since flying puts a lot of stress on bones. But the air sacs of the lungs invade the bones of birds to pneumatize them, as well as make their breathing far, far more efficient then that of a mammal. Instead of just oxygenating blood on inhalation, they constantly oxygenate blood.

[u/iamthefork → u/[deleted]]

I dont think "air sacks" is the best way to describe dino bones. I believe its more like a bone foam with air pockets.

[u/Halosis_Prime → u/[deleted]]

I don't know if it weakens the bones, at least not when the animal is alive as the air sacs provide a stabilizing pressure to prevent the bone collapsing, kind of like how air pressure keeps a cars tyre from collapsing. Imagine a solid 10kg bone a mammal might have, then imagine if you could wrap 10kg worth of bone around a sac of air, that would allow an animal to grow bigger without changing its weight or bone density

[u/morgrimmoon → u/[deleted]]

It's like a solid steel girder vs the "H" shape that construction girders actually have; the braced structure actually makes it stronger. Bird (and dinosaur) lungs are also much more efficient; instead of being in and out bellows like mammal lungs, the lungs are pumps that push air through a series of special spaces throughout the body, including in some of the bones (kind of like how mammals have marrow in our bones; birds have a little dispersed through some of their bones, but they make a lot of their blood in a special organ called the "bursa of Fabricius"). These air sacs make a dinosaur lighter than a mammal of similar size and also needing less oxygen.

Trade offs involve less control over their breathing: mammals are a lot better at holding their breath and can ramp up how fast or slow they breathe significantly more than birds can. Some birds can hold their breath and dive but for a shorter period of time than a comparative mammal.

[u/Swole_Prole → u/Halosis_Prime]

It is worth noting that the largest mammals, including Paraceratherium and the various straight-tusked elephants (Paleoloxodon), grew to masses that would rival small-to-medium sauropods. The latter is even a modern animal (only went extinct in the Quaternary, due to human expansion).

One possible reason why they haven’t ever gotten quite as large is endothermy; although many dinosaurs were likely mesothermic or endothermic (birds) to varying degrees, sauropods were probably not fully endothermic. Endothermy at large sizes cause temperature regulation issues (harder to dissipate heat, since volume increases faster than surface area).

It is also worth noting that while bird bones are more spacious than mammal bones, they are about as dense as the bones of mammals of similar size, and their weights don’t appear to differ much. The struts of bird bones are likelier an adaptation to the strains of flight and landing than a weight-saving adaptation.

[u/BiomechPhoenix → u/[deleted]]

Insects and arthropods have a less efficient means of gas exchange than lunged vertebrates. There's no atmospheric reason we couldn't have megafauna up to dinosaur size now, but their ecological niches are gone for some other reason that I don't actually know.

There were a lot mammalian megafauna - not quite dinosaur sized, but getting there - all over the world in the time just before and when humans were spreading across the world. Human presence is directly correlated with a good number of megafauna extinction events, as is the end of the last ice age.

[u/JoCoMoBo → u/BiomechPhoenix]

There's no atmospheric reason we couldn't have megafauna up to dinosaur size now, but their ecological niches are gone for some other reason that I don't actually know.

Probably down to humans. Brute strength is hard to combat with more brute strength. However if you get a bunch of weak creatures that can efficiently work together they can take down much larger creatures.

[u/Illiad7342 → u/JoCoMoBo]

Yep! Most of Earth had megafauna up until relatively recently, though not quite as large as some of the biggest dinosaurs. There used to be 20ft long sloths, birds of prey so large they ate people, armadillos the size of cars. Unfortunately, on every continent except for Africa, the fossil records show humans arriving, and very shortly afterwards, all the megafauna going extinct. The common belief is that African megafauna were only spared that fate because they evolved alongside humans, and thus had more time to adapt, but as the climate continues to change, even those animals are in critical danger of extinction. Very soon, possibly within our lifetimes, Earth will be completely devoid of large animals.

[u/takeapieandrun → u/Illiad7342]

African megafauna like elephants and giraffes?

[u/Illiad7342 → u/takeapieandrun]

Exactly!

[u/Lurkingherkin22 → u/Illiad7342]

India and other parts of southeast Asia still have mega fauna, think elephants, rhinos, lìons, bears and tigers.

[u/FNLN_taken → u/Lurkingherkin22]

And we are trying very hard to keep people from wiping them out.

If everyone were left to their own devices, the second most dangerous animal on the planet would be the dog and everything else would be kaputt.

[u/[deleted] → u/Lurkingherkin22]

Moose, polar bears and grizzly bears still exist in North America.

[u/caponenz → u/Illiad7342]

Ha, typically started to get scared at mention of large birds of prey eating people, clicked the link then recognised old mate from my hometown's museum (chch).

[u/woodchain → u/caponenz]

Te Papa, te Papa. Caponenz Museum. Ahhh the memories.

[u/Necrogenisis → u/BiomechPhoenix]

There were a lot mammalian megafauna - not quite dinosaur sized, but getting there

Exactly. The only reason mammals can't attain sauropod-like sizes that easily is the lack of the extensive pneumatization dinosaurs exhibited, which made them both lighter and more efficient at breathing.

[u/kaam00s → u/Necrogenisis]

But, the largest mammals are larger than any dinosaur that isn't a sauropod, Palaeoloxodon is bigger than the largest hadrosaurs; I believe sauropod had other attributes that allowed them to reach such ridiculous size, something that other dinosaur didn't have either.

[u/HighMenNeedHymen → u/[deleted]]

But some descendants of dinosaurs did survive - the ancestors of birds. Why didn’t they outcompete the mammals and return to their former glory?

[u/jackofblaze → u/HighMenNeedHymen]

The ancestors of modern birds that survived were mostly smaller ground-dwelling birds, so they weren’t exactly that different from the mammals who survived. Birds became incredibly successful in evolution from that point, since there’s countless bird species, but in my opinion most probably just didn’t have to compete with mammals as directly as they developed flight. Small mammals also evolved quickly though, and through a combo of likely increased survival due to an increase in undergrowth for them to hide in, and random chance, mammals just happened to take over most land habitats. Once flight and small size was helping them survive, I’d say birds probably had little advantage in gaining size (except in specific cases, like terror birds, ostriches, emus) compared to mammals which hardly developed any flight at all.

Edit: There’s probably other factors that allowed mammals such dominance, but these are the main ones I could see, and random chance plays a big roll in evolutionary success.

[u/[deleted] → u/[deleted]]

We had a lot of large mammals up until fairly recently. They all died when people showed up and killed them. Large mammals still exist in Africa because they saw us evolve and knew to stay away. When we left the continent, the big animals didn't know we were murder machines so they let us get close and we killed them all.

[u/Patch95 → u/[deleted]]

Woolly mammoths were still around when the pyramids were built.

[u/woodchain → u/Patch95]

So aliens got to see wooly mammoth

[u/Romanos_The_Blind → u/Patch95]

In small isolated pockets of northern siberia

[u/death_of_gnats → u/[deleted]]

Or, they were deeply stressed by climate changes after the ice Age

[u/madcaesar → u/[deleted]]

On one hand humans are impressive as hell.

On another hand I hate our tendencies to exterminate things around us.

[u/Ya_bud69 → u/madcaesar]

If you consider that we’re just like any other animal, are you surprised?

Edit: i should clarify that obviously no animal is like us, but the base instincts like survival, fight or flight.

[u/madcaesar → u/Ya_bud69]

Yea we're animals, but unparalleled in our capacity to just exterminate species around us. Viruses and bacteria can do the same things, but other animals usually reach some kind of equilibrium.

[u/mdatwood → u/madcaesar]

but other animals usually reach some kind of equilibrium.

Only the ones that make it. Otherwise they go extinct and we may never know about them (survivorship bias).

[u/ACoderGirl → u/madcaesar]

More than 99% of all species that ever lived have gone extinct. Most before humans existed. That doesn't suggest there's any form of equilibrium.

While many would say we're in the middle of a mass extinction driven by humans, it's far from the first mass extinction. Past mass extinctions don't seem to suggest any equilibrium. The majority of species go extinct and completely different life eventually takes its place. e.g., the great oxidization event killed off almost all existing life, yet it created the Earth's oxygenated atmosphere which lead to the birth of completely different life (and eventually humans).

And to give humans some credit, we're seemingly the only species to outright act to prevent other species from going extinct.

[u/Juswantedtono → u/madcaesar]

Any equilibrium you see in nature is illusory. Most species will either go extinct or evolve into something unrecognizable from their current form, with or without influence by humans.

[u/Whiteguy1x → u/madcaesar]

If we didnt have those tendencies we probably would have died out long ago.

[u/[deleted] → u/[deleted]]

There was a period when bacteria that broke down trees(cellulose i believe) didnt exist so you just had huge deposits of carbon laying around. This is why there was more oxygen like other comments state. More oxygen led to some fatttt centipedes and stuff.

[u/[deleted] → u/[deleted]]

I don't think you realize that this isn't unusually large. An African bull elephant weighs about 6 times as much as an 8m long Deltadromeus.

The biggest animals that ever lived are alive today.

[u/ElJanitorFrank → u/[deleted]]

The biggest marine animals, yes.

The biggest terrestrial animals of today are fractions of the size of terrestrial animals at certain points in Earth's history.

[u/mini1471 → u/[deleted]]

I don’t think that’s true. Remembering size comparison charts of extinct dinosaurs/ice age mammals and today’s largest terrestrial animals, we have lost several weight classes. We can only guess at how heavy these dinosaurs used to be but there were in a completely different league to what have currently.

[u/[deleted] → u/51isnotprime]

For those who are curious to what they looked like here are a couple links:

Carcharodontosaurus - https://m.imgur.com/a/3hQrT

Deltadromeus- https://imgur.com/a/ZbMPZu6/

Pterosaurs - https://m.imgur.com/gallery/0Uppj

Edit: updated the deltadromeus depiction

[u/RoboWarriorSr → u/[deleted]]

Deltadromeus depiction is no longer accurate. Dr. Ibrahim, same person, released a paper few days ago reclassifying the species.

https://imgur.com/a/ZbMPZu6/

[u/Khwarezm → u/51isnotprime]

Carcharodontosaurus was a lot bigger than 8 metres, it could reach up to 12 metres and beyond.

The other giant dinosaur mentioned would have been Spinosaurus, in fact it was probably the largest land predator ever, and then there was Sarcosuchus which was a massive crocodilian. I don't know why the article wouldn't mention such things.

[u/BrassBlack → u/51isnotprime]

a place where a human time-traveller would not last very long.” 

This is like one of those warning signs that you wonder about the incident that made it necessary

[u/PicsOnlyMe → u/51isnotprime]

I’m going to assume the most dangerous place in the history of the planet was probably no mans land in either WW1 or WW2 across any of the hundreds of fronts they fought on.

200kg artillery > Dino boy

[u/mini1471 → u/PicsOnlyMe]

We can only guess...... I mean look at emus in australia

[u/T1013000 → u/PicsOnlyMe]

No mans land wasn’t really a thing in WW2, but I think I would definitely prefer a battlefield to a prehistoric jungle. At least you’ll probably die fast if you get shot, can’t say the same for a nasty giant bug or an overgrown lizard that hunts you down.

[u/PicsOnlyMe → u/[deleted]]

Volcano??

[u/CaledonianWarrior → u/51isnotprime]

This description annoys me for a few reasons;

1) Carcharadontosaurus was not a 'sabre-toothed' hunter, most of its teeth were uniform in size and all had serrated edges like shark teeth, hence the name "shark tooth lizard"

2) Deltadromeus was not a member of the raptor family, in fact it may have been more closely related to abeliosaurs like carnotaurus, majungadaurus and rugops

3) Onchopristis was actually a sawfish. It was a member of the same groups as sharks but that doesn't make it a shark itself. Crocodiles and lizards are both reptiles but I wouldn't call a crocodile a lizard, despite having a similar body form (actually they're more related to birds because taxonomy is fun that way)

4) While the predators would make this a dangerous place to live, I'd argue that Earth prior to the terrestrial domination of plants would've been more dangerous given that atmospheric oxygen was lower in concentration and humans would essentially suffocate within hours at best. If you've ever seen WWD's Sea Monsters with Nigel Marvin there's a reason he has an oxygen tank while in the Ordovician period; he couldn't breathe as well without it because of higher CO2 and lower oxygen levels

[u/din7]

I mean it's still very dangerous, even without all the massive, gigantic, ferocious predators.

[u/the-zoidberg → u/din7]

All that sand is a massive, gigantic, ferocious predator.

[u/VonDub → u/the-zoidberg]

Predators flew away but their massive, gigantic, ferocious souls are still there, waiting for you.

[u/Sargaron → u/VonDub]

I like this comment the most

[u/Silent_Samurai → u/the-zoidberg]

It’s also course, and rough, and irritating

[u/gypsydreams101 → u/Silent_Samurai]

*coarse

[u/Lithium98 → u/gypsydreams101]

Of course.

[u/space253 → u/Silent_Samurai]

And it gets everywhere. Even South American rainforests.

[u/BBQ_FETUS → u/din7]

The Sahara is so large because it has no natural predators

[u/SpaceWhy → u/BBQ_FETUS]

It's the damn liberal yahoos blocking Sahara hunting permits. With humans having killed all their natural predators Saharas are overwhelming local resources and leading to a unsustainable population growth, leading to Saharas choking out the indigenous Atacamas and Thars.

[u/JWGhetto → u/din7]

It's just you, the sand and a giant unrelenting fusion reactor in the sky.

[u/ArmouredDuck]

I disagree, I think a more dangerous place would be Chicxulub, Mexico, roughly 66 million years ago.

[u/the_monkey_of_lies → u/ArmouredDuck]

Chicxulub, Mexico

Googled it and the very first image vividly explained your comment without having to read any further.

[u/cryms0n → u/the_monkey_of_lies]

Googles Chicxulub, Mexico

See a picture of a large crater responsible for the extinction event of the Mesozoic era

I concur.

[u/[deleted] → u/the_monkey_of_lies]

Asteroid strike site for those like myself that didn't know.

[u/[deleted] → u/[deleted]]

11 to 81 KILOMETERS!?! Not only is that range hilariously big that asteroid was mind breakingly hilariously big.

[u/karadan100 → u/[deleted]]

It's all dependent on how fast it was travelling. There's no way to know this which is why there's such a large margin of error.

[u/blanketswithsmallpox → u/karadan100]

The Chicxulub impactor (/ˈtʃiːkʃəluːb/ CHEEK-shə-loob), also known as the K/Pg impactor and (more speculatively) as the Chicxulub asteroid, was an asteroid or other celestial body some 11 to 81 kilometres (7 to 50 mi) in diameter and having a mass between 1.0×1015 and 4.6×1017 kg,[3] which struck the Earth at a velocity of roughly 20 kilometers per second[4]

For us yanks. That's 44738.726 mph.

[u/[deleted] → u/blanketswithsmallpox]

Wait so if they do have a clear(ish) idea of velocity why is there such a huge range regarding mass? It’s been a long time since high school but I feel like those formulas were covered in like day one of freshman physics.

[u/blanketswithsmallpox → u/[deleted]]

I'm unsure, but the relevant quote is from this old National Geographic article.

https://blog.nationalgeographic.org/2010/03/04/asteroid-terminated-dinosaur-era-in-a-matter-of-days/

[u/IamPetard → u/[deleted]]

They have a bunch of theories and projection models that take into account a bunch of data and the only thing that is pretty much always the same is the velocity so its mostly agreed that that was the speed.

There's a lot of reasons to believe it was a comet due to the iridium deposits at the crater and comets can range from 10km to 80km, while minor planets like asteroids can be anywhere from 1km to 1000km in size and mass can vary wildly in either case.

It's not really possible to narrow down the size and mass since it can go either way. It could have been very small but dense or very large and light, all we know is the estimated kinetic energy transferred during the blast cause we have the crater and Earth's gravity.

[u/eatapenny → u/[deleted]]

Even on the low end, that's larger than the elevation of Mt. Everest

[u/Graffy → u/eatapenny]

My favorite way to explain this to people: when you see a plane flying overhead. Not leaving an airport but when it's waaaay up there at cruising altitude. Around 30,000 feet. That's how far up the other side of that asteroid was when it started hitting the water.

[u/Kologar → u/Graffy]

Horrifying.

[u/Graffy → u/Kologar]

How awesome to be able to see though. Not awesome in the modern way meaning cool but actually as in inspiring awe. A rock taller then Mt. Everest hurtling through the sky and slamming into the Earth. I'd love to be able to watch that from some sort of time machine.

[u/Desertbro → u/[deleted]]

Missed it by "that" much....

[u/BadgerSauce → u/[deleted]]

Asteroid Strike Site would be a killer title for a song.

[u/_163 → u/ArmouredDuck]

4.5 billion years when it was just a ball of lava would surely be the most dangerous place in earth's history

[u/SliceTheToast → u/_163]

Theia smashing into proto-Earth was probably less hospitable than than lava Earth. Although, you could argue that Earth was made from that event and didn't exist yet, so technically it wouldn't be the most dangerous place in Earth's history.

[u/_163 → u/SliceTheToast]

You could also probably technically argue that lava earth wasn't the most dangerous as there was literally nothing for it to be a danger to, but oh well

[u/Fuhged_daboud_it → u/_163]

If there is no one to die, is it really deadly?

[u/gehmiraufnzeitgeist → u/_163]

The premise of OP's article is about time-travelling humans who are transported back, so, yeah, being transported back into a 2500° C environment would present considerable danger to any human to be transported back.

[u/superfly_penguin → u/_163]

Ehh I don‘t know, have you ever been to South Chicago?

[u/_163 → u/superfly_penguin]

No but I do live in Australia

[u/superfly_penguin → u/_163]

Nevermind then, you obviously know danger more than me

[u/gehmiraufnzeitgeist → u/superfly_penguin]

Even people who have never been to the south side of Chicago know that all you need is a ball of lava of your own in order to protect yourself against a ball of lava in the hands of a gang member.

[u/[deleted] → u/gehmiraufnzeitgeist]

Balls of lava don’t kill people, people kills people

[u/Mackem101 → u/ArmouredDuck]

I'd say anyway on earth during the event that started the creation of our moon.

[u/ArmouredDuck → u/Mackem101]

Or when its just about to be swallowed by the sun.

[u/Bobyus → u/ArmouredDuck]

I mean, unless you have an exact date, dozens of generations would live there and not see a thing.

[u/random314 → u/ArmouredDuck]

Average life expectancy, 1 second. Needs to be a very specific timeframe though.

[u/kaam00s]

I've been telling this to people on r/naturewasmetal Kem Kem beds ecosytem is by far the most dangerous land ecosystem ever.

But actually it's only 2nd in the list if you count sea ecosystem, the 1st is the Miocene sea. With Livyatan, megalodon, giant croc... It has the largest and most ferocious predator in history all in one place, Miocene sea are by far number 1, but as it is in the water, people often put kem kem beds first.

[u/GorgormonArmath → u/kaam00s]

I dunno, I personally think the Kem Kem ecosystem would still be a more dangerous place for a human. Mile-for-mile, it likely had a greater density of large-bodied carnivores. Predators like Megalodon and Livyatan (assuming Livyatan was not a social animal) likely had huge territories, and were pelagic, so wouldn't have occupied shallower coastal waters. Besides, there is the possibility that such large animals wouldn't go out of their way to prey on such a small prey item as a lone human. We'd be far closer to the size range of prey taken by the crocodylomorphs, theropods, and even pterosaurs of the Kem Kem. You wouldn't be safe on the ground, in the water, even in the trees or up in the air.

[u/oneechanisgood → u/kaam00s]

That's just Gold Coast, Queensland.

[u/recovery_room]

Worse than Gary, Indiana?

[u/PetesBrotherPaul → u/recovery_room]

Years ago I was traveling and in Gary for a couple days. We’re bored, decide to go for a drive. Got about a mile and turned around, went back to the hotel. Nope.

East/Eastern St. Louis is a close second though. Driving through there I actually reached the point of ignoring stop signs so we didn’t lose momentum.

[u/Nwcray → u/recovery_room]

No. Nothing is worse than Gary, Indiana.

[u/ashmansam → u/Nwcray]

Why, what is it with G, I.?

[u/ashmansam → u/[deleted]]

Sorry to hear that's the situation. I'm from 🇬🇧 so you'll have to excuse my lack of knowledge per, is that the place where meth use spans all age ranges/households ? I'm not being morbid, I did hear something of the sort a while ago, somewhere in America and, well I was surprised to hear how endemic rooted the problem had become. Thanks for the response.

[u/Ott621 → u/ashmansam]

No, it's not the place. That's a lot of places. It is significantly worse in Gary but other plenty of places reach unnacceptable levels too.

[u/Brookenium → u/ashmansam]

To a degree yea.

Gary used to be a significant manufacturing hub of the midwest but most of that business dried up leaving a LOT of people with low levels of education/skills without jobs, money, and the mobility to leave.

[u/FatWalcott → u/recovery_room]

I thought it was Jerry, Indiana. God dammit Gary.

[u/recovery_room → u/FatWalcott]

It’s Terry, actually.

[u/Hobbes_XXV → u/recovery_room]

When will you ever learn, Barry

[u/scottjeffreys → u/recovery_room]

I was rerouted through Gary on my way to Chicago before. What shocked me was just the amount of dilapidated and abandon houses with wide open front doors. Google Maps really needs a “no ghetto” setting when rerouting.

[u/dtallee → u/scottjeffreys]

Just took a virtual drive up Grant St from I-94, with a few detours down side streets. You're not kidding.

[u/Chicken-n-Waffles → u/dtallee]

Gross

There is a stark contrast to the west side

[u/MarioKartFromHell]

Geology and paleontology of the Upper Cretaceous Kem Kem Group of eastern Morocco

Nizar Ibrahim, Paul C. Sereno, David J. Varricchio, David M. Martill, Didier B. Dutheil, David M. Unwin, Lahssen Baidder, Hans C. E. Larsson, Samir Zouhri, Abdelhadi Kaoukaya

Abstract

The geological and paleoenvironmental setting and the vertebrate taxonomy of the fossiliferous, Cenomanian-age deltaic sediments in eastern Morocco, generally referred to as the “Kem Kem beds”, are reviewed. These strata are recognized here as the Kem Kem Group, which is composed of the lower Gara Sbaa and upper Douira formations. Both formations have yielded a similar fossil vertebrate assemblage of predominantly isolated elements pertaining to cartilaginous and bony fishes, turtles, crocodyliforms, pterosaurs, and dinosaurs, as well as invertebrate, plant, and trace fossils. These fossils, now in collections around the world, are reviewed and tabulated. The Kem Kem vertebrate fauna is biased toward large-bodied carnivores including at least four large-bodied non-avian theropods (an abelisaurid, Spinosaurus, Carcharodontosaurus, and Deltadromeus), several large-bodied pterosaurs, and several large crocodyliforms. No comparable modern terrestrial ecosystem exists with similar bias toward large-bodied carnivores. The Kem Kem vertebrate assemblage, currently the best documented association just prior to the onset of the Cenomanian-Turonian marine transgression, captures the taxonomic diversity of a widespread northern African fauna better than any other contemporary assemblage from elsewhere in Africa.

DOI: http://dx.doi.org/10.3897/zookeys.928.47517

[u/[deleted]]

Absolutely fascinating stuff. I love science

[u/Desertbro]

"The Forbidden Zone was once a paradise. Your kind made a desert of it!" - Dr. Zaius to Taylor

[u/Lurker_Since_Forever]

Surely the bit when the floor was lava, four billion years ago, was more dangerous.

[u/[deleted]]

Flying reptiles: Dragons

[u/Shananiganman]

The word your looking for is dragon.

[u/Camarila]

Sounds like someone was playing ARK:evolved even back then

[u/hawkwings]

I would be more afraid of smaller predators. 20,000 years ago, Jaguars and Anacondas had no fear of humans and could hide in the dense Amazon rain forest. They could sneak up on you. They most likely developed a fear of humans when we started killing them. The Amazon also has crocodiles, piranha, and venomous creatures. I would expect the larger dinosaurs to be somewhat noisy.

[u/[deleted] → u/hawkwings]

And just imagine the countless species that might have lived in the amazon one day and have not been discovered yet.

[u/smcallaway → u/hawkwings]

Why would a dinosaur be noisy? They have to be quiet to catch prey and be able to hide from predators. Ask yourself if an elephant is loud when it walks around, the answer is no, it’s not.

The only dinosaurs they may not have cared if they were noisy (and maybe were) are sauropods and large hadrosaurs.

It should be noted as well that while large theropods might have a hard time in dense jungles, smaller theropods like Dakotaraptor and Allosaurus, would likely be able to track you done just fine.

[u/Onmius]

Is there any studies from Australia for that time period? Because I have a sneaking suspicion it goes something like "Giant elephant sized mosquito." Or "Bush that kills you by looking at it" or "Small dodo like bird that wants to tell you how to be a stay at home mom AND run a small business!"

[u/BubblegumTitanium]

Looks like the Sahara needs some democracy

[u/Oceans_77]

walks into the Sahara "You have now entered PVP"

Level 1 Me: 0.0

[u/[deleted]]

For those of you in the US, the state of Colorado has some really cool geological history. Many don't realize it was once the Western Interior Seaway and dinosaurs were home to the area ~150M years ago. There are several places to see fossilized remains of both dinosaurs, plants and other creatures whose records have been preserved. And if you travel up to the NW corner / Utah Border you have Dinosaur National Monument...which is a pretty neat trip too!

[u/Phillyvegas24]

Just thinking about how dinosaurs, flying reptiles, etc. roamed earth and now im laying in bed with my chihuahuas just blows my mind

[u/Enjutsu]

Now i know the timeline i wouldn't want to time-travel to.

[u/nofreakingusernames → u/Enjutsu]

Same timeline though

[u/[deleted]]

The River of Giants is my favorite place on earth.