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Ancient fires drove large mammals extinct, study suggests

nytimes.com

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Re: Ancient fires drove large mammals extinct, study suggests

#121

Post by angiosperm »

Stevvo wrote: post #90
pmayrgundter wrote: post #10

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 200…

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.

Re: Ancient fires drove large mammals extinct, study suggests

#122

Post by angiosperm »

celtoid wrote: post #44
pmayrgundter wrote: post #10

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 200…

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.

Re: Ancient fires drove large mammals extinct, study suggests

#123

Post by angiosperm »

kvetching wrote: post #66
TheBlight wrote: post #61

Earlier quoted context omitted.

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)

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

Re: Ancient fires drove large mammals extinct, study suggests

#124

Post by angiosperm »

sigil wrote: post #92
dimmke wrote: post #77

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. Th…

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!

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

Re: Ancient fires drove large mammals extinct, study suggests

#125

Post by angiosperm »

dimmke wrote: post #93
Tagbert wrote: post #87

Earlier quoted context omitted.

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 eno…

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.

Re: Ancient fires drove large mammals extinct, study suggests

#126

Post by angiosperm »

AbrahamParangi wrote: post #71
codexb wrote: post #9

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 hig…

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…

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.

Re: Ancient fires drove large mammals extinct, study suggests

#127

Post by AbrahamParangi »

angiosperm wrote: post #126
AbrahamParangi wrote: post #71

Earlier quoted context omitted.

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…

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?

Re: Ancient fires drove large mammals extinct, study suggests

#128

Post by deafpolygon »

Reason077 wrote: post #109
myshpa wrote: post #8

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 e…

> "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…

> 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.

Re: Ancient fires drove large mammals extinct, study suggests

#129

Post by CatWChainsaw »

stonetrw wrote: post #54
codexb wrote: post #13

Earlier quoted context omitted.

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 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.

Re: Ancient fires drove large mammals extinct, study suggests

#130

Post by cyberax »

angiosperm wrote: post #119
cyberax wrote: post #75

Earlier quoted context omitted.

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 tim…

> 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.

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