Ancient fires drove large mammals extinct, study suggests
nytimes.com
nytimes.com
"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...
"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...
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.
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.
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.
https://www.youtube.com/watch?v=npXY8mu2hhU&list=PLmd4S3n7Pl...
http://scholar.google.com/scholar?q=younger+dryas+impact+hyp...
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.
(he was also on Joe Rogan)
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.
I remember an episode like that, IIRC it also had some crazier claims like pyramid complexes resembling calculator circuit boards.
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.
An ice age ended, and humans invented agriculture. Combined, these are very big things for the world. Magic/aliens not required.
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.
https://coolinterestingstuff.com/mysterious-alignment-of-anc...
Surviving. I learnt a new word.
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.
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!
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.
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.
https://www.usgs.gov/programs/climate-research-and-developme...
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.
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.
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!
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.
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.
Obviously the large animals that have a lot of meat (and might knock down your house) are an obvious target to catch.
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).
After a few years, you have a massive mammoth graveyard and mammoths are extinct. Doesn't seem at all surprising.
It is very much expected, and well documented.
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.
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.
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.
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.
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.
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.
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.
"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."
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.
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.
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.
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)
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
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?
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.
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).
>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
> "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.
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...
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
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
>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
This happened in Australia. All the local megafauna disappeared rapidly once humans settled in.
It's far more likely that people simply poked animals to death with sharp sticks.
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.
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.
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.
It seems to be a pattern to this day. I view the flames as a kind of Asmovian terraforming.
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.
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.
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 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.