What are some alternative theories as to what caused the K-T Extinction Event? I feel like the meteor is just too perfect. Is it true that the dinosaurs were already starting to die off even before the meteor, and that the meteor was just the catalyst for the point of no return?
>THE ICE AGE
There was undeniably an impact event that happened.
The problem is the fossil record is really spotty because fossilization itself only happens under very specific circumstances that don't happen a lot.
There are a lot of theories, and little evidence.
Personally I suspect the reality is a combination of a lot of things.
Overspecialization and niche partitioning creates a situation that wasn't able to change as fast as the climate was with the breakup of the continents could have created an ecological collapse, a particularly nasty illness weakening keystone species. And then a big ass space rock came in and put the nails in the coffin for them.
Mammals being unsupposing and opportunistic rushed to fill the niches that were open in a recovering planet.
There is a thin layer or iridium, an extremely rare spaceborne metal, covering the entire world at precisely the same point dinosaur bones stopped existing. The KT mass extinction event was caused by an asteroid impact, that is as much a geological fact as any.
Giant evil brain
The dinosaur with 500 teeth fucked it up for everyone
>What are some alternative theories as to what caused the K-T Extinction Event?
REALLY fucking stupid ones like "mammals ate all their eggs" or random climate change or the dumbest one of all: hyperdisease. The last two have also been used to try to explain the Late Pleistocene extinctions. And hyperdisease makes even less sense in that context.
>Is it true that the dinosaurs were already starting to die off even before the meteor
Not even remotely. The very last moment of the Mesozoic was when all the most famous dinosaurs like Triceratops and T. rex lived.
Dinosaurs are in the Hollow Earth
The meteor absolutely happened, although that alone wouldn't have been enough. What's often not talked about enough imo is that the Deccan Traps were eurupting at that time and flood basalt euruptions correlate very well with almost every other mass extinction.
Some interesting videos to watch:
Did the meteor strike trigger the Deccan Traps, or was the Deccan Traps eruption already happening and the meteor was simply the coup de grace?
The traps were erupting for several hundred thousand years at that point. And no, a meteor of even that size doesn't have enough energy to transfer through the earth and cause an eruption on the other side despite this once being theorized. Computer modelling and siesmic tomography of the mantle and as a result better understanding of the properties and nature of the earth's interior proved this couldn't happen. Even if an object FAR larger than the Chixilub impactor hit and punched clear through the earth's crust it wouldn't be enough, and it would insinerate the entire earth's surface before that happened like in this kino:
Do you think that what was mentioned earlier (not sure if it was you) about biodiversity beginning to fall - assuming that our knowledge of that isn't just because of gaps in the fossil record - was part of this? That biodiversity among the dinosaurs was dropping due to "evolutionary adaptation" in the wake of the Deccan Traps erupting and affecting the animals not adapted to it?
In some ways, do you think it's possible that the meteor strike could've prevented a P-T Extinction Event, considering a similar event with flood basalt eruptions?
Unlikely, also not me. I am always skeptical of "biodiversity" estimates from prehistory as the fossil record is a fraction of a fraction of past's endemic species so it's likely not very accurate.
Although, one of the main reasons dinosaurs were so successful for so long was the low biodiversity caused by the devastating Permian mass extinction and Triassic mass extinction which makes sense. They filled every niche before anything else really got a chance and especially because of Pangea allowing species to propagate all over there wasn't a whole lot of opportunity for speciation.
The Cretaceous if anything had the most biodiversity of the Dinosaur age since Pangea had long since split and the main clades that dominated former Gondwana in the southern hemisphere had speciated a fair bit from their northern counterparts (Abelisaurids and Sauropods dominating in the south vs Hadrosaurs, Dromeasaurs and Tyrannosauroids in the north).
And the P-T event was unique since it was from our understanding far more massive than most basalt eruptions and also happened in the middle of a massive continental craton which likely built up immense pressure and created many opportunities for seeps and release of more volcanic chemicals into the atmosphere. The Deccan traps, while destructive, didn't occur in the right place or right conditions to make something like that happen afaik.
Supposedly biodiversity was beginning to fall when compared to earlier eras, but that's not necessarily a precursor to an extinction event, and could also just be indicative of a hole in the fossil records rather than the actual state of ecosystems.
But the evidence for the meteor theory is pretty compelling at this point. The Chicxulub crater was found, and the geological layer of tektites (essentially tiny obsidian pebbles thrown by the blast) are as good as a wall between lots of dinosaurs -> very few (large) dinosaurs. If it matters, probably the more important aspect of the meteor was the rapid environmental changes than the immediate event, the fallout of which was relatively limited.
>the fallout of which was relatively limited.
According to online posts the firestorm resulting from the impact circled the entire earth and anything that wasn't underground or underwater died.
Relatively in the sense of time and eventual scope, I mean. I don't think the immediate disaster - the blast, the firestorm, the tsunamis - quite absolutely covered the planet, but the rapidly changing pH balance of the world's oceans and the atmospheric dust blotting out the sun worldwide for years on end was really the death-knell for all megafauna that might have survived the initial catastrophe. As is often the case in ecological collapse, it comes from the bottom up; otherwise, those top niches can just be filled by something else, given time. That's my understanding of it, anyway.
Sounds to me like your mistaking the blast zone for the entire world. What you describe would not have reached every part of the globe.
>Supposedly biodiversity was beginning to fall when compared to earlier eras
I don't even think that's paleontologically accurate. The heyday of Stegosaurs and Sauropods was the Jurassic, but Hadrosaurs and Ceratopsians didn't even exist until the Cretaceous, and Sauropods - even enormous ones - lasted right up until the comet.
The current pet theory is that dinosaurs were endotherms. Problem is, that's not really supported by the evidence. It's likely the global winter the Earth was thrust into was enough to kill off everything that didn't have feathers (and probably most things that did). Most of the groups that survived outside of dinosaurs have defense strategies against cold: crocodilians go to deeper water and don't need to eat for months, pond turtles hibernate. Smaller animals could have survived in any number of refugia. Ectothermic megafauna, however, would have been fucked. Hell even most endothermic megafauna would have been. You don't even need to add any other factors.
It doesn't need to physically freeze them to death, the entire world was hothouse so all the plants were tropical. They would die out quickest with global winter for years and once those die out the food chain collapses and only very small things that don't need to eat a lot survive. The oceans also likely acidified and underwent deoxygenation which killed off many species there.
>It doesn't need to physically freeze them to death
Nobody even implied it did.
No, even with the record we have, that idea is outdated and wrong. I'm not even entirely sure why it came into fashion. I can guarantee you, however, that it was INEVITABLY one fucking man who had a pet theory, then everyone parroted it, because that's what always happens in paleontology.
>I'm not even entirely sure why it came into fashion.
the asteroid impact hypothesis is quite new, and most of the paleontologists working today were alive before it was discovered.
so the hypothesis didn't "come into fashion." It was the only explanation we had. You guys are literal children so you don't know any of this.
What the fuck are you talking about? We've already stated several popular theories of the days before the comet was known about. The "dinosaurs were already going extinct before it hit" nonsense is by far the worst.
>The "dinosaurs were already going extinct before it hit" nonsense is by far the worst.
it was the only serious hypothesis around.
disease and mammals eating eggs weren't hypotheses because neither one could be tested or falsified.
there was only one hypothesis. It was that diversity declined to the point that extinction happened.
you guys are also not scientists, so you don't understand this.
The idea that the Deccan Traps contributed was also not a serious hypothesis because it couldn't be tested. Also that idea appeared after the impact event was already discovered.
I'm not reading the thread, but another idea you guys probably haven't talked about is how the proliferation of angiosperms resulted in a landscape unfavorable to gigantic megafauna.
but that's also not an hypothesis because it cannot be tested or falsified.
That was mentioned. That one at least makes SOME sense though. The extinction of Stegosaurs is suspected to be due to the dominance of cycads tapering off.
Yep. It's a reasonable explanation but impossible to test. We know what plants were diversifying at the time dinosaurs disappeared, but there's no way to link the two events.
That's why scientists love the impactor hypothesis, there's a shitload of evidence that it caused the extinctions.
>It's a reasonable explanation but impossible to test
It WOULD be reasonable. If it weren't for the fact that the transition from gymnosperm dominance to angiosperm dominance doesn't really seem to have had much of an effect. People need to realize this shit didn't happen overnight and animals had time to adjust. Stegosaurs were weird specialists for some reason. Most Dinosaurs weren't.
>If it weren't for the fact that the transition from gymnosperm dominance to angiosperm dominance doesn't really seem to have had much of an effect.
if diversity declined in forested areas, it happened at the same time angiosperms proliferated.
but it's not clear that such diversity loss actually occurred.
>but it's not clear that such diversity loss actually occurred.
Exactly. Probably the best studied area for Dinosaurs is Campanian-Maastrichtian Western North America and Dinosaurs did just fine over that transition, right up til the comet. Again, Alamosaurus was one of the largest dinosaurs that ever lived and it held out to the very end. Same with T. rex. Same with Triceratops. Even Parasaurolophus may have survived past the Campanian. And I wonder how much of this takes into account chronospecies like the line from Centrosaurus to Pachyrhinosaurus. You can't really count those as "extinctions" in the light of an extinction event anymore than you can say a class of kids turning into adults through public education is the same as a school shooting.
Yep, the other problem they had was comparing desert faunas to earlier forest faunas. Of course desert faunas were less diverse and less likely to produce fossils.
when that's corrected for, the loss of diversity disappears.
As I've said in previous threads, I think most Mesozoic "deserts" weren't. I think the amount of deserts is really overplayed. It especially doesn't make sense when there are lots of huge dinosaurs like Sauropods involved. But the depositional environment is extremely important. And a lot of this is just bias of one form or another. When you actually look at the record, Dinosaurs were doing magnificently right up to the very second of the impact.
>sand dunes fossilize
>salt pan fossilizes
>rivers, lakes, ponds, and oceans also fossilize
>types and sizes of sand fossilize
>water literally fossilizes
>water temperature fossilizes
>water consumed by dinosaurs fossilizes
>temperature of water consumed by dinosaurs fossilizes
>number and type and mixture of plants fossilize
>temperature of water consumed by plants fossilizes
Most of the mesozoic world was deserts. Something like 99% of mesozoic rocks are deserts without dinosaurs. The desert rocks of the mesozoic cover almost entire continents.
You're free to think what you like, but geologists are just going to read your thoughts and wonder why you have this opinion.
>Most of the mesozoic world was deserts.
This is factually wrong.
>This is factually wrong.
It IS factually wrong since most of the mesozoic world was oceans.
but of the land, almost all of it was deserts for almost all of the time. You're only aware of the rock formations that produce fossils while ignoring the literal millions of miles of mesozoic rocks that don't.
Not them, but I thought oceans could be classified as deserts because of low precip
This is fucking stupid. There isn't a Mesozoic map in existence that agrees with your nonsense. Even the mainstream ones that almost certainly overclassify regions as "desert".
without seeing your map I can't tell where you went wrong. But my first guess is you're ignoring the entirely of the triassic, jurassic, and the first half of the cretaceous.
my second guess is that you're looking at a geological map and think if only a tiny sliver of a formation is exposed, that's as big as it is.
either way, retardation.
> A lot of substrate doesn't reveal Mesozoic fossils because it's too young, too old or was underwater.
this is some flood geology sort of shit. Please tell me more. How can mesozoic rocks be too young, too old, or to wet for fossils?
>without seeing your map I can't tell where you went wrong
Literally THE WORLD. At any point during the Mesozoic.
>this is some flood geology sort of shit. Please tell me more. How can mesozoic rocks be too young, too old, or to wet for fossils?
Bruh you're legit retarded.
>Literally THE WORLD. At any point during the Mesozoic.
Here's a pic of the second largest mesozoic rock formation in the US. It's desert sand dunes and covers much of the american west. The largest formation is also desert sand dunes and covers much of the same areas.
>Bruh you're legit retarded.
no, I'd love to hear your thoughts on this. Sounds fascinating and funny.
>the second largest mesozoic rock formation in the US. It's desert sand dunes and covers much of the american west. The largest formation is also desert sand dunes and covers much of the same areas.
both have millions of miles of desert with no fossils. Representing tens of millions of years on the planet.
and at that time the continents were just starting to break up, so these same deserts show up all over the world. They used to be one huge desert that covered the earth and lasted tens of millions of years with almost no interruptions.
You can not know anywhere near as much about geology as you seem to think and not be aware of different fucking strata being present in different locations. See all that blue and orange? It's impossible for Mesozoic rock to be there because those LAYERS OF THE FUCKING EARTH ARE GONE.
yes, that's what I figured
you don't understand that under all those cenozoic rocks are mesozoic rocks.
cute, but absolutely retarded.
Dude you make some of the shittiest posts in the entire history of Wauf. You need a medal or something.
are you denying that there's mesozoic rocks under the cenozoic?
and you still haven't explained how mesozoic rocks could be too young or too old for fossils. I'm guessing that was a mistake and you meant rocks in general? Like some rocks are too old and some too new, but those aren't mesozoic rocks?
I think your reaction to realizing you fucked up is to insult the person that points it out to you.
because you're embarassed.
don't be embarassed, nobody here knows who you are and you can go right back to saying wrong stuff without anyone being the wiser.
I don't know why you're trying to convince everyone that dogs are just small bears. They're obviously not. Take meds.
>See all that blue and orange? It's impossible for Mesozoic rock to be there because those LAYERS OF THE FUCKING EARTH ARE GONE.
luckily almost all of those areas were under the ocean for most of the mesozoic and don't matter for gauging climate on land.
Again, factually wrong. Much of the eastern US was above water, but those layers are gone.
When did you stop hitting your wife?
>Much of the eastern US was above water
I said most of that area was underwater for most of the mesozoic.
most doesn't mean all.
sets and subsets.
>When did you stop hitting your wife?
if I misunderstood your mistake please explain
I'm pretty sure I understand it though. You just forgot that not all rocks are mesozoic rocks, or skipped over the part where I said "mesozoic."
I just don't understand why you think the state bird of Montana is the wombat. That's a weird thing to think.
hey, if I'm misunderstanding you,
you're free to explain.
I was hoping for some crazy flood geology shit where old mesozoic rocks were too old to have fossils and new mesozoic rocks hadn't grown any fossils yet. But the actual explanation isn't nearly so entertaining. You weren't talking about mesozoic rocks.
What the fuck. Why would you call me a sea scorpion? You're clearly wrong. TAKE MEDS.
don't get hysterical, woman.
it was a simple misunderstanding.
you forgot we were talking about dinosaur fossils.
I just don't understand why you think Triceratops is a Sauropod.
I'm happy I was able to guess your mistake with the geological map, but to be fair you're not the first person I've seen make that mistake.
I was showing my wife the Morrison Formation on a map some years back and she commented on how tiny it is. I had to explain to her that those were just the areas where it was exposed on the surface. It covers millions of miles, but it's buried under younger rocks in most of the places it exists.
There's no way in hell you have a wife. She'd kill you in a week.
she's an extremely patient woman. Also I'm rich and moderately good looking so that helps.
My father also works at Nintendo.
the difference is I've been doxxed at least 10 times on Wauf so there are people here that know who I am and what I've accomplished.
Seems to me your biggest achievement is being chronically online and consistently arguing with points nobody ever made.
You should probably go back and delete your posts if you're going to pretend you never said something.
>being chronically online and consistently arguing with points nobody ever made
as I've mentioned,
I'm less interested in what you say and more interested about how your brain brought you to the point of saying it.
I'm curious about your thought processes.
In this particular case the error seems to have been thinking geology takes place entirely on the surface of the earth when in fact we spend a great deal of time drilling, digging, and mining to see what's underneath. Geology is 3D, not 2D.
so we're not limited to studying the rocks on the surface, that's silly. Most of our work happens hundreds of feet below the surface. Often thousands of feet. Particularly since that's the main goal of the science. To see what's below the surface in case it's useful.
You didn't say you don't know this. But the things you said very much indicate that you had forgotten it.
no, it's pronounced "Geo."
but close enough.
And you're being dumb as fuck. A lot of substrate doesn't reveal Mesozoic fossils because it's too young, too old or was underwater. Just because you don't find dinosaur fossils in a place doesn't mean it was desert. Holy shit. And some places, like the Appalachians just aren't that well explored.
>Just because you don't find dinosaur fossils in a place doesn't mean it was desert.
no, but if you don't find fossils, and instead find sand dunes without signs of water, pollen from desert plants, and oxygen isotopes indicating high average temperatures, it's fucking desert.
here. I did offer the disclaimer that one can't necessarily trust the palaeontological record to reliably estimate biodiversity, but I was mentioning it in passing as it's a theory that has been aired (see: Condamine, F.L., Guinot, G., Benton, M.J. et al. Dinosaur biodiversity declined well before the asteroid impact, influenced by ecological and environmental pressures.). I can't say I buy it myself, but
wanted to know some alternative theories to the meteor impact.
>Condamine, F.L., Guinot, G., Benton, M.J. et al.
Dear god, this is from 2021. Are paleopsued nufags going to resurrect every stupid theory about Dinosaurs within the decade or what? These gays need to enter a different field and stop fucking up everything.
How can any of you make claims to what theories are right or wrong with certainty when there's controversy over events in Rome that we still have writing on, or even current politics?
Because the "controversy" in paleontology over these theories is LITERALLY the SAME "controversy" over Rome. There is no actual fucking controversy. A few shitheads with a lot of influence are passing off sloppy work that reinforces their worldviews and outright lies and nobody has the power to kill the bastards. Rome literally collapsed because of christians. Every single detail of its collapse is well recorded and the christian emperors literally INTENTIONALLY caused it. The only reason anyone believes otherwise is that after the Dark Ages (Early Medieval Period), christfags started realizing bragging about bringing down the pagans wasn't winning them points. It was making them look like savages. So first the catholic church, then around the 1980s, first Stephen Jay Gould and a number of other """""""""scholars""""""""" started spinning the hell out of European history to make it seem like christians were the saviors of knowledge and culture and caused a flourishing of science and brought peace on Earth when none of that bullshit ever happened and we have the records to prove it. MOST stupid theories in paleontology are the same way. It starts out with everyone knowing they're wrong, then a cult following pops up around one or two influential bastards, then they derail the entire field for a generation.
Oh, I should mention, Gould is active in both of these fields, coincidentally. Also, guess the early life section.
>Oh, I should mention, Gould is active in both of these fields, coincidentally.
he's one of the least active paleontologists around.
Somebody dors not seen to understand roman history outside from reddit memes
there's a broad consensus among paleontologists that dinosaurs went extinct directly because of the K-Pg bolide impact.
whether or not they were becoming less diverse before that is a subject of debate, but it also doesn't matter.
radiation from supernova
Mammals ate all the dino eggs.
The newly evolved flowering plants poisoned herbivorous dinosaurs.
A deadly disease from outer space killed them.
Oh and the Deccan Traps mass eruption or some shit...
Those are some of the theories provided by my childhood dino books
The meteor was the catalyst in my opinion. Meteors that hit Saturn's moon of Calisto literally stopped its tectonic plates and halted all volcanic activity so it is not surprising that a meteor would fuck up earth. The firestorm would be the first result after the actual impact. Then earthquakes, volcanic eruptions, tsunamis, ash storms/clouds, wildfires, and everything else you can think of ravaged the planet. Then would come the lack of biodiversity and the "bottleneck" effect where only the surviving species were left to fill the niches.
I don't believe any of those but it's creative thinking I guess. The evolution of mammals and flowering plants really would be too slow to kill off so much of the planet's life that quickly. Life would adapt before it could be wiped out in that way. The disease idea is more interesting though. Dinosaurs fighting aliens sounds badass ngl.
I remeber those old theories. But logically, most of them never realy made sense. Since mammals, birds, plants and marine organisim were effected too. The deccan traps of corse is another story. It bfing likely a supporting factor.
Why in the ever-loving fuck would plants want to poison the creatures that help spread their seed? And why aren't they still doing that to herbivorous animals today? Braindead theory, up there with "hurky durr megalowdawn wuz ay scavengur"
>Why in the ever-loving fuck would plants want to poison the creatures that help spread their seed?
because eating seeds usually destroys them rather than spreading them
>And why aren't they still doing that to herbivorous animals today?
they very much are.