[HN Gopher] Giant sloths and mastodons lived with humans for mil...
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Giant sloths and mastodons lived with humans for millennia in the
Americas
Author : wglb
Score : 67 points
Date : 2024-12-22 22:37 UTC (3 days ago)
(HTM) web link (phys.org)
(TXT) w3m dump (phys.org)
| CT4u8798 wrote:
| I wonder how long it will be before other theories of Graham
| Hancock are found to be plausible or true instead of him being
| dismissed as a crackpot fringe conspiracy person?
| AlotOfReading wrote:
| Which of Graham Hancock's claims do you think this supports? It
| certainly isn't the one about a global seafaring proto-British
| empire from the last ice age, considering how far inland it is,
| the technology is off, and it vastly predates his hypothesis
| for the global apocalypse.
|
| The Santa Elena Rock shelter people have been making this
| argument for years now. Between the questionable lithics,
| dating, and excavation methodologies they don't have sufficient
| evidence to support the claims they're making and they've
| offered no convincing explanations for why the standard of
| evidence should be lowered given the massive chronological
| issues their dates would suggest (<5000 years after Yana 10k
| miles away!).
| gausswho wrote:
| I wonder how long it will be before theories, beliefs,
| superstitions, hunches, are no longer combined with grievance
| and pride and packaged up as somehow empirically relevant.
| NetOpWibby wrote:
| The first Power Rangers!!
| Qem wrote:
| > There was this idea that humans arrived and killed everything
| off very quickly--what's called 'Pleistocene overkill,'" said
| Daniel Odess, an archaeologist at White Sands National Park in
| New Mexico. But new discoveries suggest that "humans were
| existing alongside these animals for at least 10,000 years,
| without making them go extinct.
|
| I don't think there is a contradiction here. Indeed we could have
| them get extinct, it just took a long time by human standards,
| ~10 millennia. I don't know how many mastodons or giant
| sloths/armadillos there was in Americas before humans made
| landfall here. But I'd guess about 10 million of each. If they
| took about ten years to reach sexual maturity, that gives us
| about 1000 generations of megafauna in this time window. To get
| their population down from 10 million to just one in this time,
| each generation had to be smaller than the predecessor, but on
| average could still retain log(10^-7)^-1000 ~= 98.4% of its size.
| Even if stone age tech enabled humans to overhunt them
| consistently only by a slight amount, ~1.6% each generation, they
| still would end extinct in 10,000 years. So it was not "without
| making them go extinct". It was "while making them go extinct.".
| Swizec wrote:
| 10,000 years is quite a lot in human time. The pyramids were
| about 5,000 years ago and look how much has happened since.
|
| By comparison, we killed off the Dodo in, what, less than 10
| years?
|
| I think it's fair to talk about 10,000 years as a long time.
| Sure it's barely a blink in geologic time, but we're talking
| about the human perspective here.
| Aloisius wrote:
| The Dodo lived on a tiny island and it was driven extinct
| largely by invasive species brought by humans.
|
| It took humans quite a bit longer to drive say, the tarpan,
| to extinction.
| BillyJoeLouBob wrote:
| Also around the same time don't forget that dinosaurs lived with
| Jesus too. But only in America.
| ChrisMarshallNY wrote:
| _> But some archaeologists say it 's hard to imagine that humans
| would repeatedly traverse a site and leave no stone tools._
|
| Those tools were _really valuable_. They busted their butts,
| making them, and wouldn 't want to toss them aside, just because
| they got chipped or cracked. They are much more likely to throw
| them into a "spare parts bag," and keep them around.
|
| Today's throwaway culture is actually pretty new, in human
| history. Just hang around some poor folks, to see radical
| conservation, in action.
| AlotOfReading wrote:
| Lithics were, broadly speaking, more akin to how we treat
| plastics than metal tools. Lithic production results in enough
| waste that archaeologists give the waste a special name
| ("debitage") and even use it for destructive testing that would
| be unthinkable for more significant / less voluminous
| artifacts.
| ChrisMarshallNY wrote:
| Thanks. Was not aware.
|
| The other possibility, is that most of their tools were
| composed of biodegradable stuff, like wood, bones, and
| shells.
|
| In Africa, they used wood and raw iron for their stuff (I
| have spears, shields, and arrows, from there). That doesn't
| tend to age well.
| AlotOfReading wrote:
| That leaves other evidence that's been looked for.
| Additionally, the Eurasian cultures that peopled the
| Americas are all known to have been heavy lithic users.
| ChrisMarshallNY wrote:
| Somewhere, I have an old stone hand axe. It's really
| well-made. Not sure where it's from, but I believe it
| came from a European Stone Age dig, about fifty years ago
| (probably stolen. People weren't so circumspect, in those
| days).
| jandrewrogers wrote:
| I am skeptical of this assertion.
|
| If you walk the mountains of Nevada along the fossil shoreline
| where the Lahontan[0] civilization thrived, you will regularly
| find large quantities of neolithic trash strewn about. Broken,
| half-finished, or abandoned stone tools are ubiquitous. It
| takes little effort to find obsidian arrowheads, some in
| perfect condition.
|
| The preponderance of the evidence is that these were viewed as
| disposable artifacts, use once and throw away. If they were
| actually valuable, they could have picked these up in the same
| way we pick them up today. It would have essentially been "free
| money" lying on the ground. Yet for some reason, in all the
| intervening millennia, so few people did that modern humans can
| find them everywhere.
|
| [0] https://en.wikipedia.org/wiki/Lake_Lahontan
| ChrisMarshallNY wrote:
| You are probably correct. This is not my area of expertise,
| and I likely made an assertion that has weak support.
| mkl wrote:
| > Sloths weren't always slow-moving, furry tree-dwellers. Their
| prehistoric ancestors were huge--up to 4 tons
|
| No, modern sloths are not descended from giant ground sloths. The
| rest of the article might be okay, but it's hard to trust it
| after a mistake like that.
| bahmboo wrote:
| Are you sure? " The Megatherioidea also includes the three-toed
| sloths of the genus Bradypus, one of the two sloth genera still
| alive today."
| pvaldes wrote:
| Eels and tuna lived for millennia also, and will be extinct in a
| couple of human generations. When ecosystems collapse, they do it
| really fast, even after years of abuse.
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