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Ancient fires drove large mammals extinct, study suggests (nytimes.com)
150 points by gumby on Aug 17, 2023 | hide | past | favorite | 125 comments



Seems that Younger Dryas Impact Hypothesis might fit these observations too.

"We obtained radiocarbon dates on 172 specimens from seven extinct and one extant species... spanning 15.6 to 10.0 thousand calendar years before present (ka)."

YDIH event is estimated at 12900 BP and includes vast wildfires in its scenario, including in North America.

Contrast that with the idea that humans have been in Sapiens form for 200kya+, using fire for longer even than we have been Sapiens and have probably been in the Americas far before 13kya. Is the idea that despite the capability, we only at this specific time started the extinction program? At just the moment when there's sign of a globally catastrophic impact?

YDIH seems more parsimonious, yet the paper doesn't mention it.

https://en.wikipedia.org/wiki/Talk:Younger_Dryas_impact_hypo...


Humans could have lived nicely in harmony for hundreds of thousands of years in times of abundance, and when sudden cataclysms caused great famines or suffering they could have resorted to more drastic measures that caused large scale fires.

Doesn’t mean this is what I think happened, but sounds just as plausible as comets causing havoc to me.

In the end IMO this field has been greatly disserviced by Hancock. The yDIH just as well might have been the correct explanation but this guy won’t stop yapping about aliens alongside the same. So the “establishment” academics seem to be very wary of this hypothesis and being associated with him. Now it’s clear that’s dumb of the academics as well, they should be logical and choose the correct hypothesis no matter what flavor it associates them with. Sad that one of the likely most important times of human history has become so contentious due to human emotion and ego coming in the way of scientific rigor.


I agree with most of this. I would say Graham Hancock has some crazy ideas, but the Younger Dryas isn't crazy and his impact on the theory is minimal. If anything the fact that Joe Rogan had him and Randal Carlson as guests on JRE at the same time probably had more impact.

My current thoughts are that the true history of human civilization does go much further back than current narratives and "Experts" claim. Our current civilization has progressed and innovated so much in such a short amount time, it is not unreasonable to expect that humans have built and lost similar civilizations through catastrophes such as the YDB.

It may not have been aliens but I think it is probable that right around the time we started going into space, ancient human made satellites were discovered and brought back to earth. It could also be that Area 51 and other places were created not for Alien space craft crashes but ancient human satellites that were intentionally crashed.

I can only imagine how alien a TESLA found in space by the next civilization might seem!

Considering the way our government leaders and wealthy have historically conducted themselves, it's not hard to believe if they survived a cataclysm, they would be quite willing to be thought of as gods and horde any knowledge they have to themselves.

Fun subject to ponder in anycase!


Just for the record, Hancock has never promoted aliens. He's dead wrong a great deal, but not that wrong. His crime, though, is to have been annoyingly right too many times, for all the wrong reasons. YDIH is just one such case.

Hancock's great strength is that he actually goes to all the places he writes about, and his wife takes great pictures. I forgive all his maundering in exchange for the pics.



He is saying modern reports of aliens are equivalent to previous reports of fairies. It is not common to believe in fairies, even among loonies.


A little more reading..

"All extinct mammals dated in this study have last occurrence dates older than 13.00 ka, with a modeled extirpation time estimate across all taxa of 13.07 to 12.89 ka [using the Gaussian-Resampled Inverse-Weighted McInerney (GRIMW) extinction estimator"

Even tighter bound than my comment and still a tight fit around 12900. Figure 1 in their paper shows this as well.

In other news, there was recently a "comprehensive refutation" of YDIH (pre-print) that a fave of my, Martin Sweatman, takes a good look at.

A lot of this debate comes down to careful dating, error bars, etc.

https://martinsweatman.blogspot.com/2023/08/debunking-hollid...


What’s more intriguing to me beyond the YDIH is that clearly something wild happened during the Younger Dryas period, impact or not.

Regardless of what caused the dramatic fluctuations in temperature, wildfires, ocean levels (floods) and megafauna, the fluctuations did occur, and mark the beginning of human civilization as we know it, even though we also know Homo Sapiens existed long before this period.

To imagine a period potentially as short as 100 years where the world went from unbearably cold at its warmest to the perpetual summer world we live in now and mega predators simply vanished… if I lived through that period I’d also tell my children to amass resources urgently (and tell stories of the hell world we came from). Who knows how long this insanely human friendly world might last!

The idea that our species oldest stories might be about catastrophic climate change is absolutely humbling.


https://en.wikipedia.org/wiki/Asterix_and_the_Falling_Sky

Edit: Hrrmph.That was not exactly what I remembered. What I do remember are several references to "The Sky is falling!" in the preceeding comics. Which I later found to be actual reference to some Gauls saying that to Roman elites, when asked about their greatest fear. As written down in some classical latin texts, which I don't remember right now.


Nicely put!


Not directly related but I recall watching a "documentary" on Discovery where this guy claimed that several monuments across the globe all matched up star patterns and similar astrological events from around 12k years ago IIRC.

What I recall best was some pyramids ligning up with how the stars would have been back around that time, but they've since drifted apart. He also talked about Angkor Wat and some in South Americas.

My memory is very fuzzy as this was a casual watch over a decade ago, so I don't recall the name of the guy or if the speculation had a name. I assumed it was pretty out there, though of course as presented it sounded compelling.



Thanks, that must be the guy. His 10500 BC lines up with 12k years ago, but yeah...


This sounds a lot like Ancient Apocalypse on Netflix, but that was released in 2022


These days you can find information supporting any theory so take this link with a grain of salt but I found this and believe it relates to your recollection.

https://coolinterestingstuff.com/mysterious-alignment-of-anc...


Are you maybe thinking of Ancient Aliens?

I remember an episode like that, IIRC it also had some crazier claims like pyramid complexes resembling calculator circuit boards.


Can't recall, though from what I recall it wasn't that out there.

What I do recall was that the main point was that these monuments were linked to something astrological, be it stars, equinoxes or similar, "that the same time" some 12k years ago.

That's why I thought of it in this context. If it were true, and the timing lining up with these big animals going away, did something big happen 12k years ago?

Of course, not taking some random guy on Discovery's word for it. But fun coincidence to think about.


Absolutely something big happened 12800 years ago: a massive comet strike that melted much of the North American ice sheet and started continent-wide wildfires. The record is seen unambiguously in a spike of massively elevated platinum dust, and sulfur from fires, frozen into a layer of polar ice.

30+ genera of, mostly, big mammals went extinct suddenly, along with the Clovis culture.

The big remaining mystery is what happened 1200 years later to end the Younger Dryas cold spell.


> If it were true, and the timing lining up with these big animals going away, did something big happen 12k years ago?

An ice age ended, and humans invented agriculture. Combined, these are very big things for the world. Magic/aliens not required.


Yeah wasn't suggesting aliens by any means.


Antonio Zamora has done some research in the Younger Dryas Impact Hypothesis and the Carolina Bays of North America. He's worth the gander.

https://www.youtube.com/watch?v=npXY8mu2hhU&list=PLmd4S3n7Pl...


The Carolina Bays cannot have been formed less than 30kya. Suspicion is on a meteor strike in Michigan back before then, thus distinct from the YD impact.


YDIH is based on false assumptions imo. Check out Robert Schoch's 'solar induced dark age' theory. Schoch deconstructs a lot of YDIH's claims.


Robert Schoch is often wrong. And, he cannot account for the layer of platinum dust and wildfire smoke in the Antarctic and Greenland ice cores.


In addition to seed vaults, we need "carbon vaults" but in a soil core style and we can comm with futures on the states of our environ, not just seeds.

Also, and catagorically -- we need the EVERYTHING of seed vaults to be open and public.

How were these chosen, put in there, harvesting, maintaining, climates, history -- there are PBs of data that need be included in these things.


I would suggest reading the high-ranked Google Scholar results rather than a highly fraught and questionably influenced Wikipedia talk page or a blog by a highly opinionated author.

http://scholar.google.com/scholar?q=younger+dryas+impact+hyp...


Just a jump-off point for anyone not acquainted. It's a sprawling topic, as the 20k results of your search show!

I'd also recommend Sweatman's research review:

https://www.youtube.com/playlist?list=PLftb0lOpSe9PvJhFKSueZ...

24 videos, 30-60m each, stepping thru over 120 papers. It's the most comprehensive synthesis I've found that actually deals with the debate. Sweatman is an advocate for the hypothesis, but he does an admirable job of focusing on the ideas and there's a lot to learn from him.


Younger Dryas Impact Theory has always been somewhat controversial but it has basically become political due to being JRE listener coded now.


I prefer Robert Schoch's theory that it was a solar outburst (aka micro-nova) rather than a comet that dramatically warmed the entire Earth.

(he was also on Joe Rogan)


His theory on the aurora borealis that would have covered the planet and been more intense is very interesting. Esp the drawings of a human shaped figure with the balls near the armpits across the world. Which was later shown to be the result of some plasma interference or something or another that would have been seen around the world and drawn.


A solar outburst would not have deposited a layer of platinum dust.


Do you mean iridium? I hadn’t heard of the platinum dust later previously


The K-T bolide scattered iridium dust. The YD bolide scattered platinum dust.


> extant

Surviving. I learnt a new word.


impacts were an effect, not the cause


Sometimes I go down these Wikipedia rabbit holes, and one of the most fascinating to me is extinct animals that were not dinosaurs.

Specifically, how a lot of mammal apex predators are similar to extinct versions, just like, half the size. Like the American Lion and Direwolf.

Also how this was relatively recent, as others have pointed out they think that a lot of these species went extinct around 10,000 years ago. That fits even conservative estimates of when humans had migrated to the Americas.

This is an aside, but I found it really fascinating. Alligators and crocodiles are kind of obviously in the same area from an evolutionary standpoint (they're both in the Order Crocodilia), and they're both thought to be incredibly old - 30 million+ years.

But there are only 2 species of Alligator left in the entire world. There's the American alligator which is fairly plentiful all around the Southeast United States and a slightly smaller critically endangered variant in China. There's 18 species of Crocodile, and they're in all the Americas, Australia, New Zealand, all of Asia and a huge portion of Africa. And then I learned about Caimans which I didn't even know existed before. It really goes to show how some branches can be so much more wildly successful than others.


You might enjoy the In Our Time episode on Crocodile Evolution.

https://open.spotify.com/episode/2v7Dil3bVNiir5BDXxGnTe?si=o...

There were crocs with beaks, crocs with plant-grinding molars, crocs that ran around upright on land (yikes). During Earth’s colder periods their range narrows to equatorial regions, and it expands northward & southward during warmer periods. They may rule again someday!


This was incredible. It blew my mind. Thank you so much. I had no idea that crocs were basically the other side of dinosaurs.


Crocs with administrative skills are a stretch, even for me.


There have been recent evidence that seems to push that 10,000 year entry of humans into the Americas out by as much as another 10K further back.


Yes… but there’s so many factors at play that I don’t know enough to speculate with any hope at accuracy about (but will because it’s interesting.)

These were modern humans so they had sapience and tools and some form of organization, but how widespread were they vs. the so called “megafauna” - we are talking about A LOT of species with very different biologies here that went extinct. And the timescale isn’t long enough so we know the smaller versions of some of these creatures existed at the same time.

Plus, was the hunting for food or defense? If primarily for food, how was the meat preserved? Its easier to imagine a group of humans with spears taking down a lone Direwolf than a pack of giant creatures.

It’s hard to reckon with humans being the primary factor in the demise of these creatures when there are still things like grizzly bears out there. I’m sure they didn’t help and in very select situations were the primary cause (such as when a very small isolated species was stuck on an island) but I just don’t know if I buy them being the primary cause of a large scale extinction of a type of organism.

The earliest estimates for large scale civilizations like the Mayans were around 7000 BC. It’s hard to imagine humans having such a widespread and profound effect without that level of organization.

But I’m a complete amateur on this subject, so this speculation is basically just what I find plausible with some cursory research. Clearly this is a hotly debated topic amongst scientists.


There is no possibility that this sudden extinction pulse is because of humans. People lived in the Americas for many thousands of years with hardly any effect on fauna, then suddenly, boom! And the Clovis people disappeared right at the same time.


If it took humans so long to get to America from Asia, it seems plausible that they were confined to the Pacific coast for a long time as well, but high rates of erosion and seismic activity could easily destroy the evidence. It's certainly counterintuitive that the first place people colonize would be the semiarid high plains of New Mexico!

The easiest places to cross the American Cordillera are in southern Mexico (Chivela Pass), Nicaragua (San Juan River) and Panama. But these places are also very rainy.



I'd be highly skeptical of this claim.

Large megafauna around the entire world began dying off both before and after the last glacial maximum, even in areas where there wasn't a significant human presence. The fact that they died off in North America around that time, too, isn't that surprising.

It's also worth noting that at that time, a large part of North America was covered in savanna, which is among the most highly fire-prone habitats, regardless of humans.


Hold on though, because the correlation between “human arrival” and “megafauna extinction” is extremely high. The timeline of megafaunal extinctions goes: Africa, then Eurasia, then Australia, then North America, and finally South America. No points for guessing the order that humans colonized those continents.

In the few historical examples of human introduction to a new ecosystem (New Zealand and Madagascar) within a few hundred years of arrival we’d eaten every animal bigger than a cat.


Groups of humans bigger than 10 can, with planning, catch pretty much any wild animal, even without equipment. Simply digging a hole and tricking the animal into it is one approach.

Obviously the large animals that have a lot of meat (and might knock down your house) are an obvious target to catch.


Island extinctions are a distinct phenomenon. People never managed to drive anything in Eurasia extinct. Even African and Indian elephants still exist. The North American extinction pulse clearly matches the platinum-dust spike from the comet strike.


What about the woolly mammoth, steppe mammoth, straight-tusked elephant, European hippopotamuses, aurochs, steppe bison, cave lion, cave bear, cave hyena, Homotherium, Irish elk, giant polar bears, woolly rhinoceros, Merck's rhinoceros, narrow-nosed rhinoceros, and Elasmotherium to name a few?


How many of those do we have plausible evidence were done in by people?

Of course Irish elk are island fauna. Lions persisted in Europe into the Classical period, finally done in by Roman industrial-scale collection (not comparable to hunter-gatherer hunting).


There have also been large finds with many dead megafauna together. It is not expected that humans at that time had the ability to slaughter very large numbers of megafauna all together.


> It is not expected that humans at that time had the ability to slaughter very large numbers of megafauna all together.

It is very much expected, and well documented.

https://en.wikipedia.org/wiki/Buffalo_jump


If humans find a technique to catch a mammoth (eg. lure it into a big hole), then they will eat mammoth meat... But next week, when the uneaten mammoth meat has gone bad, they will catch another.

After a few years, you have a massive mammoth graveyard and mammoths are extinct. Doesn't seem at all surprising.


https://upload.wikimedia.org/wikipedia/commons/a/ad/Extincti...

Humans were the reason, on all continents.

https://ourworldindata.org/wild-mammal-decline

"By around 10,000 years ago we see a huge decline of wild mammals. It’s hard to give a precise estimate of the size of these losses millennia ago, but they were large: likely in the range of 25% to 50%."

"It wasn’t just that we lost a lot of mammals. It was almost exclusively the world’s largest mammals that vanished. This big decline of mammals is referred to as the Quaternary Megafauna Extinction (QME). The QME led to the extinction of more than 178 of the world’s large mammals (‘megafauna’)."

We lost the biggest animals because those were the ones we hunted. If the reason were to be the fire (which sounds ridiculous), it would have caused the extinction of mammals of all sizes, not just the largest ones.


> Humans were the reason, on all continents.

The article doesn't disagree, saying both "increased fire activity spurred by people" and "Dr. Dunn emphasized that this pattern could not account for the notable disappearance of large mammals elsewhere in the world at the end of the last ice age".

> If the reason were to be the fire (which sounds ridiculous), it would have caused the extinction of mammals of all sizes, not just the largest ones.

No, not necessarily. A small animal can retreat into a burrow an elephant-sized one cannot. They also breed faster afterwards, allowing their populations to recover more readily.


The mass extinction of large megafauna, all around the world, at roughly the same time, isn't explained by humans (see woolly mammoths). There's far more evidence that it was driven by climate change as the world quickly exited the last glacial maximum.


It’s both.

Human populations were growing rapidly and simultaneously the period from 50000-10000 was the end of the last ice age

So the going theory is that the original areas of climate for which mega fauna were most populous, was effectively reduced increasingly over time as a result of warming, which humans were able to capitalize on to the point where we kind of “finished the job.”

This is effectively, how we see extinction patterns around the globe. Whereas humans aren’t necessarily the primary or only cause, but they do make a big enough exogenous impact to cause a collapse.


How big of a population are we talking here


https://ourworldindata.org/wild-mammal-decline

"What’s most shocking is how few humans were responsible for this large-scale destruction of wildlife. There were likely fewer than 5 million people in the world. Around half the population of London today."


Well the estimates are kind of all over the place but basically growing from ~1M - 15M over the course of 40000 years, before the Neolithic explosion


https://edition.cnn.com/2019/10/08/us/woolly-mammoths-death-...

Last mammoths died 4000 years ago, and they might have even lived longer, if short-term events hadn’t tainted their water and drained their food supply.

It wasn't climate change that killed off the mammoths; it was humans.

https://www.google.com/search?q=mammoth+house&tbm=isch

We ate them all. It was only when there were no big animals left to hunt that we invented agriculture.


And yet, for some reason, ancient humans decided not to eat all the elephants.

No, it was climate change.

The last, small population of mammoths that survived until 4000 years ago on Wrangel Island never came in contact with humans. They died because they were ill suited for the climate they lived in.


Humans got rid of plenty of elephants. "Both" is likely the answer in all of these extinction events.

https://www.nbcnews.com/id/wbna7548514

> One million years ago, elephants and their cousins roamed the five major continents of the earth. Then humans came along. Today elephants can be found only in portions of sub-Saharan Africa and South Asia.

> The two most argued hypotheses for their decline are climatic changes and over-hunting by humans. A recent archaeological expedition dug up information that may support the latter.

> Exploring 41 sites ranging from 1.8 million to 10,000 years old, Todd Surovell of the University of Wyoming found that interactions between humans and elephants matched up with successive waves of human population expansion. As the human populations in those sites continued to grow, the number of elephants shrank and, in some sites, disappeared.


You do realize that the majority of elephant species are extinct and the ones left have less than a fraction of their historic range?


This is a bit of a tangent, but I think the phrase "you do realize" rarely, if ever, seems to add anything to the debate. It sounds patronising at best, and makes people defensive even if it's a useful point.


> ancient humans decided not to eat all the elephants

Who knows why? Larger size, slower reproductive rates, and adaptations to colder climates? Maybe elephants were more socially organized and were harder to hunt? Maybe their habitats were not so densely populated by humans? We can only speculate.

> No, it was climate change.

While climate change certainly played a role, it's undeniable that the QME would not have been as extensive if it weren't for human involvement.

> never came in contact with humans

That's not clear, iirc.


Elephants and humans must have evolved together, that could have helped the elephants.


It seems somewhat incredible that mega fauna survived the previous two dozen or so ice ages just fine then went extinct as soon as humans figured out how to live in huts.


Something so innocuous turning catastrophic... But don't worry guys AI will totally 100% be aligned with not fucking humanity over.


Given historical and prehistorical evidence, I think it fair to say that even in the cases where humans were not responsible, it was not through lack of trying. Human societies gorged themselves until they had to adapt to scarcity, at which point I think we started developing concepts like living in harmony with nature, agriculture and land management.


Climate change potentially caused by catastrophic comet impacts.


> "Humans were the reason, on all continents."

Except the numbers don't really stack up. 10-15k years ago the entire global population of humans was, at best, a few million. And a single megafauna kill would produce enough meat to feed an entire community for weeks. Humans would have had to have been extremely bloodthirsty and systematic in their slaughter, and must have been wasting enormous quantities of meat.

Also, the regions where some megafauna species survive into modern times (ie: Africa and South Asia) were where most of the humans lived. Wouldn't we expect those species to have gone extinct too?

It's certainly possible that humans helped finish off megafauna populations that were already scattered, distressed, and in decline. But it's unlikely that we were the primary or only cause.

> "We lost the biggest animals because those were the ones we hunted."

There's plenty of evidence that ancient humans hunted animals of all sizes. Why would we only go after megafauna as they became rarer and rarer? Instead of smaller species that were far more numerous and accessible?


> And a single megafauna kill would produce enough meat to feed an entire community for weeks.

Meat spoils in warm weather within days. Weeks would be assuming they had refrigeration. We're not sure when the practice of curing and drying meat started, and if they had not been practicing that... then it would be a megafauna every few days.


> https://upload.wikimedia.org/wikipedia/commons/a/ad/Extincti...

There are several findings of humans being present in North America much earlier than 13 000 years ego. One recent paper in Science: https://www.science.org/doi/10.1126/science.abg7586

A longer list in a thread 6 months ago: https://news.ycombinator.com/item?id=34525911


Would be interesting if the myth of Dragons breathing fire was because we used fire to kill the largest/scariest megafauna.


We probably used fire to cook them with, and probably cause a lot of accidental fires in the process ;) Also bare in mind that except for africa those megafauna would have been relatively tame and way too unsuspecting of meat eating humans.


There's a lot of theorizing that early sapiens intentionally set fires to clear thick, impassable forests and kill game in the process. The cleared areas would make post-fire hunting easier as well.



> thick impassable forests

Trad burning in Australia has largely been to cool burn undergrowth in the forest areas (relatively small land area) and to patch burn open grass lands (majority of area)

eg: https://youtu.be/wZL5rITqpwU?t=208


I note that the megafauna extinction was done by people of all races and creeds, long before capitalism existed.


This, I think, is part of the controversy.

In Australia there's this "noble savage in tune with their environment" thing about the Indigenous people; that they are custodians of the land and live in harmony with nature. The idea that they are also responsible for the mass extinction of the megafauna is incompatible with this idea, and therefore unacceptable.


I've been in Australia 60 odd years, frequently in contact with anthropologists in the Kimberley and PNG.

The noble savage trope died out years ago - haven't seen much of that in any serious circles since the back to nature french quasi-anthro types were grooving to La Vallée by Barbet Schroeder (with the Pink Floyd soundtrack).

> The idea that they are also responsible for the mass extinction of the megafauna is

.. pretty hard to land, save for the possibility of a small number.

https://en.wikipedia.org/wiki/Australian_megafauna

Head on down to "Causes of extinction" and read carefully, there are a lot of some's.

    New evidence based on accurate optically stimulated luminescence and uranium-thorium dating of megafaunal remains suggests that humans were the ultimate cause of the extinction for some of the megafauna in Australia.
The evidence we have (sure, there may be unknowns) is that the bulk of the megafauna were dwindling as a result of the environmental changes following the end of glaciation.

Humans in Australia appear to be responsible for, at most, the final death blow to a few of the species that were on their way out already.

If you have evidence to the contrary I'd gladly accept it.


No evidence, but anecdata. Glad to hear it isn't taken seriously by actual anthropologists. Thanks for the info :)


Doesn't explain the ones frozen in place still in the process of chewing grass.


[flagged]


> Expect to see more grasping at straws to try to blame climate change or whatever.

It's grasping at straws to propose that the end of an ice age might involve some climate change?

Human predation certainly played a role, but pretending the ice caps melting can't have is... something.


The dynamics of evolution are really interesting. As an aside, we like to say we can't predict what life would be like on an alien world as we only have one data point but honestly, I really do wonder if there isn't some universality in the patterns that have evolved here. But I digress.

Becoming bigger seems to a strategy driven largely by herbivores as a defense mechanism against predators. Predators seem to get bigger as a response. At least on land. At sea, it seems to work a little differently (eg we have whales that are the largest animals ever to live on Earth that live on very small animals).

But being large seems to be a fundamentally risky proposition that sooner rather than later leads to extinction. It just seems harder to adapt. If your food source gets disrupted, it's basically game over. IIRC I read something recently where the megalodon was theorized to have been driven to extinction by the emergence of the (smaller) great white shark that basically stole it's food source (combined with scarcity for other reasons).

Then again, dinosaurs were around for 150 million years so what does that say? Was the Earth just relatively stable for that period? Still, dinosaurs died out while birds lived on (and thrived).

The end of the last Ice Age killed off a bunch of our larger animals too (eg the wolly mammoth; yes I know it survived in isolation for some time later).


Horses are native to North America and became extinct after the introduction of humans. https://en.wikipedia.org/wiki/Evolution_of_the_horse

>Fossil evidence indicates that mastodons probably disappeared from North America about 10,500 years ago as part of the Quaternary extinction event of most of the Pleistocene megafauna that is widely believed to have been a result of human hunting pressure. The latest Paleo-Indians entered the Americas and expanded to relatively large numbers 13,000 years ago, and their hunting may have caused a gradual attrition of the mastodon population.

From https://en.wikipedia.org/wiki/Mastodon#Extinction

As far as megafauna and climate, see also https://en.wikipedia.org/wiki/Revival_of_the_woolly_mammoth


If you read the study itself, it claims that it's still hard to say what the relative roles of ice age climate change cycles vs. human predation were on the extinction of large Paleocene mammals in North & South America (and Australia):

> "Despite decades of research on extinction causality, the relative importance of late-Quaternary climate changes and spreading human impacts have been difficult to disentangle because poor chronological resolution in the fossil record has precluded alignment of these rapidly occurring, tightly linked phenomena."

However, it seems pretty clear that wherever humans showed up into new habitats where humans and large animals didn't have a shared ecological-evolutionary history (i.e. not Africa or Eurasia) extinction rates among the megafauna shot way up:

https://ourworldindata.org/quaternary-megafauna-extinction

> "Africa was the least hard-hit, losing only 21% of its megafauna. Humans evolved in Africa, and hominins had already interacted with mammals for a long time. The same is also likely to be true across Eurasia, where 35% of megafauna were lost. But Australia, North America, and South America were particularly hard-hit; very soon after humans arrived, most large mammals were gone. Australia lost 88%; North America lost 83%; and South America, 72%."

Maybe large animal populations had shrank due to the spread of glaciers during the Last Glacial Maximum era (c. 25 kya) so they were more vulnerable, but the new factor (relative to the past 2.5 million years of ice age cycles) was the human predation.


"Fire-stick farming" (i.e. burning forests to make hunting easier) is said to have helped Aboriginal Australians sort out their megafauna.


Australian forests evolved to burn every few years. Any megafauna living in Australia would know how to survive a forest fire (as modern fauna in Australia does), because they'd experience them regularly.


>Australian forests evolved to burn every few years.

Except that seems to have happened after they started burning them.

>Any megafauna living in Australia would know how to survive a forest fire (as modern fauna in Australia does), because they'd experience them regularly.

As per above, not really. Also as many animals worldwide experienced, surviving a bush fire is not as hard as surviving a bald ape with a pointed stick.

https://theconversation.com/how-aboriginal-burning-changed-a...


A fire burns out the brush, making it easier to see what you are hunting, and easier to chase after it.


This is great new information helping to further the debate about causes of the Quaternary Megafauna Extinction (QME).

I’ll reiterate here my theory that the specific period following this extinction event, was catastrophic for human civilization and drove humanity to invent property and thus the system of capital and exchange.

[0] https://en.m.wikipedia.org/wiki/Quaternary_extinction_event

[1] https://kemendo.com/Myth-of-Scarcity.html


So kind of interesting, in trying to find a way to view the gist of the content behind the above paywall, I found this article from about 5 years ago:

https://www.npr.org/sections/thetwo-way/2018/04/19/604031141...

> New Study Says Ancient Humans Hunted Big Mammals To Extinction

> Smith found that when humans arrived someplace, the rate of extinction for big mammals rose


The NYT article is a theory that considers human behaviors besides hunting:

>In a new study published Thursday in the journal Science, a group of paleontologists that analyzed fossil records at La Brea Tar Pits, a famous excavation site in Southern California, concluded that the disappearance of sabertooth cats, dire wolves and other large mammals in this region nearly 13,000 years ago was linked to rising temperatures and increased fire activity spurred by people.

This is the article the NYT is citing: https://www.science.org/doi/10.1126/science.abo3594


Interesting, fits the current thing… well?


It’s a living.


More likely, early humans simply killed off the large herbivores, and the large predators simply starved.

This happened in Australia. All the local megafauna disappeared rapidly once humans settled in.


The fire hypothesis is compatible with what you said. The idea is that humans either directly or indirectly caused frequent and vast wildfires that destroyed ecosystems, and those fires either killed animals directly or destroyed the resources they needed to survive.


Not really? Megafauna disappeared everywhere in Americas, including in the Central and South America, that are not susceptible to massive wildfires.

It's far more likely that people simply poked animals to death with sharp sticks.


It is completely impossible that people drove all these animals extinct with sharp sticks. People lived in the Americas for thousands of years without affecting them noticeably, and then they all disappeared suddenly, 30+ genera strong, along with the Clovis people.

We know from polar ice cores that the Americas were shrouded in dense smoke 12,800 years ago from fires started by the comet strikes at that specific time. Central and South America are certainly susceptible to massive wildfires, like anywhere shrouded with combustibles.


> It is completely impossible that people drove all these animals extinct with sharp sticks.

Why? Spears are extremely effective and deadly.

And it happened everywhere else. Megafauna also disappeared in Asia, as soon as humans appeared.

> People lived in the Americas for thousands of years without affecting them

In other words: animals existed for hundreds of thousands of years, but they disappeared within several hundred of years, right as human settlement waves moved across the Americas.


> Spears are extremely effective and deadly.

And continents are big, and people very unevenly distributed. 13kya there were few humans on any continent. It takes more than spears to eliminate mastodons, mammoths, short-faced bears, dire wolves, sabretooth cats, cheetahs, camels, horses, giant sloths in one blow.

Humans did not drive 30+ genera to extinction in the Americas all in under a century, after coexisting for millennia; and did not lay down a film of dust enriched with platinum over the whole continent, or torch it. They did not wipe out their whole material culture at the same time. Nothing Clovis, or any of those genera, are found anywhere above the layer of platinum-enriched charcoal and ash dust.

Horses and elephants did not become extinct in Eurasia, where people hunted far longer. You might notice Africa still sports plenty of megafauna.


How do you think some of those humans hunted in Australia? They would travel to a burnt forest (or set fire to one) and then walk around eating the cooked animals until they'd rotted or been eaten, and then move on.


And we still haven't outgrown that behavior. We as a species keep burning the proverbial forests to get an easy win.


We are maturing. We will mature. We grow up with heroes these days. Thanks to intrepid companies like Disney who, and despite polluting right wingers best efforts, we have a trove of emotional education material for our next generation. Marvel and Harry Potter are the two greatest inventions of the past 100 years- even more than the mRNA vaccine.


I don't quite follow. Marvel teaches folks to punch their way through problems, and Harry Potter teaches people it's OK to be manipulated by adults because it's your destiny.


https://www.hcn.org/articles/wildfire-people-are-starting-a-...

It seems to be a pattern to this day. I view the flames as a kind of Asmovian terraforming.


There is a certain myth that pre-industial peoples were in a more balanced relationship with nature.

While less powerful technologies and thus more direct dependence on natural processes and cycles made people more atuned to nature, the broad pattern seems to be one of unhindered consumption (deforestation, hunting etc) the impact of which was limited only by the relatively small population size.


The Avatar and noble savage myth. Also used to blame all the ills of modern society on colonialism (and thus capitalism). If only we could go back to living like the indigenous lived!. Well, evidence doesn't favor them being any more noble.


We used to be limited by what our stomachs could carry, but every leap in technology amounted to storing up more food and resources for later, or consuming them conspicuously for social status, particularly to attract mates. So nowadays not even a few lifetimes of wealth (tens of millions of dollars) is enough to sate.


And by the lack of our present day very powerful tools.

https://en.wikipedia.org/wiki/Harvester_(forestry)

That sort of thing can level a whole forest in a very small fraction of the time it took to grow.


Dude, I wake up, turn on the radio, and feel like an extinct megafauna every morning.

I'm sure my skull will end up in a closet at the office and taken out every now and again to confer on an old codebase.


The next set of wild fires will eliminate the current dominant mega fauna.

The common HOMO-Extreme-BMIans.

Or in the vernacular, Large Human Corporate Drone.

Typically feeding on vast quantities of cheese-wiz over bacon fries, their combined fat mass contains the combustible energy of the worlds combined nuclear stockpiles.


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Both things can be true: that ancient fires drove large mammals extinct, and that sea level rise cause a specific local species to go extinct when its habitat was fully flooded.


So why doesn't the Western media still push the discourse of sea-level rise and "NYC is going to get drowned any minute now!"?


Because rising sea levels doesn't get clicks anymore, but if you read actual literature on the topic, there are ongoing concerns and considerations. On a more practical level, it's not a major North American or European city, so it doesn't capture Western media's attention, but the Republic of Kiribati[1] has an estimated <80 years before it's primary land masses are completely submerged, with some being lost nearly 20 years ago.

Kiribati is a canary in a coal mine for climate change related activity in coastal regions. The government of that nation has very progressively purchased land in Fiji, and presumably in other places to aid with resettlement efforts. There have been legal tests (and denials of claims) for at least one person claiming to be a climate refugee from Kiribati. Even before the sea levels rise, the arable land and liveable areas will be wiped out.

This isn't theoretical, it just isn't directly affecting (yet) the exceedingly wealthy, major western cities, or white folks, so it doesn't get as much press.

Some other areas that are starting to recognize the impacts of rising sea levels include Kolkata, Guangzhou, Miami, New York, and more directly personally affecting me, Vancouver! Unfortunately the main point of recognition is that significant portions of these cities will be below sea level at some point in the next century, barring solutions like seawalls, and other methods to try to save them. It's been almost 20 years since the levees failed in NOLA, but it hasn't stopped people thinking we can hold back the ocean. Things are going to be crazy in the next couple of decades.

[1] https://en.wikipedia.org/wiki/Kiribati


Kiribati, in more than one way is living in the future. For two hours of the day are 2 calendar days ahead of most of us. (Being UTC+14)



I don’t understand your point. It seems to be that Western media is somehow biased, but I’m not sure in what way. I’m pretty confident that global temperatures will continue to rise and that sea levels will rise and cause massive problems for coastal populations over my lifetime. But I’m mostly consuming Western media. Do you disagree with these points? And what non-Western media do you feel is more correct?


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We actually should unite globaly. The existence of countries is a historic relict that is only causing troubles.


We actually should divide, city-states is where it's at. The existence of countries is a historic relict that is only causing troubles.


They were probably releasing too much CO2 into the atmosphere /s


has anyone done a study on whether total annihilation of most organic life by fire is bad for us? which profit-oriented megacorporation is currently saying they will save us? does Elon know about this?




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