I don't buy this. If the article explains it correctly, the argument is that they can show that in place where the climate was stable, and humans were new, the megafouna went extinct. But that implies that they believe that there were places on the planet were the climate was stable. If you look at the greenland Ice core data, you can see extreme peaks and falls around the last quarterly extinction. So sounds like BS to me.
I think you are being downvoted because you are using the appeal to authority: 'trust them, they have credentials that say they should be trusted on this very subject'.
This repurposed quote from the raiders of the lost ark might also work:
Yeah, I was thinking it was that or my probably-unneccessary flippant attitude. (And btw, I truly do appreciate HN's habit of trying to explain downvotes.)
I just get triggered at low-effort skepticism. Tomsaga read the word "stable" and assumed it meant "absolutely stable", and didn't ask himself "huh, I wonder if the pop-sci article is masking a more complicated concept with an easy-to-digest concept".
To get more into the climate stability: What they're doing is measuring the difference in temperature and precipitation between the Last Glacial Max and the Last Interglacial. And the maps don't even have `0` in their range, they have a small number but not zero. So yes, climate wasn't stable, but they were able to measure "how stable" it was. (Pages 1-3 in the paper.)
I think an appeal to authority is only fallacious when it's an appeal to an authority that has no relevant expertise. Something like "my dentist says that anthropogenic climate change isn't real, you don't think you're smarter than a doctor do you?"
In contrast, when it comes down to John Q. Internet vs a scientist with relevant expertise, I think it's a reasonable heuristic to think the scientist is more likely to be correct.
IMO the downvotes were more related to the delivery than the content.
Interestingly, there seems to be an equality bias[1] where the experts opinions weight no more than any other person's opinion. So apparently the reasonable heuristic isn't always applied in how we perceive and judge information.
Yes, but appeal to authority is still appeal to authority as opposed to discussing the merits of the idea. In this place we are better than that. Or we should be.
If the discussion was "who is more likely to be right", well, that's a different matter and I'd agree with credentials. But that's not an interesting discussion really.
IIRC, their hunting method consists of having saliva that is so infested with pathological bacteria that they simply bit their prey and wait for it to succumb to fevers.
Somehow, I doubt eating their meat is a healthy thing to do, even when cooked.
EDIT: turns out that the BBC documentary I got that from has outdated information:
> Although previous studies proposed that Komodo dragon saliva contains a variety of highly septic bacteria that would help to bring down prey, research in 2013 suggested that the bacteria in the mouths of Komodo dragons are ordinary and similar to those found in other carnivores.
On the other hand komodo dragons actively hunt humans which is pretty impolite. I would expect that bad habit would lead to their extinction on a small island but it hasn't.
Imagine if, instead of spending your childhood, teenage years and early adulthood in schools, you just spent it learning to hunt, then continued to learn and practice hunting for the rest of your life. Imagine if everyone in your family, and everyone else you knew had also spent their entire lives learning to hunt and hunting. Imagine if every genius born into every generation devoted their entire intelligence to the problem of hunting, from their first moment to their last. Imagine if this had been going on for generation after generation, with knowledge and expertise refine and passed down through mentorship and oral tradition.
Collectively, it's a level of intellectual effort that humanity has likely never brought to bear on any other problem besides, perhaps, farming. As such, it's perhaps no surprise that early humans were spectacularly successful at hunting so many of even the largest and most fearsome animals to extinction.
That's a crazy thought. It's also a crazy thought to extrapolate that process all the way to how current first world countries operate. You can kind of start to bridge the gap between the two and see that our society is just an extreme manifestation of that whole scenario you described. We know that in fact there was a direct set of events that got us here, but it's also easy to separate the way humans lived and how we live now, as if they are detached but you can see a lot of those early behaviors still operating in our industrialized society.
It is a good thought, but I would like to add, that even in pure hunters societys, you also had different professions. You need to process and store the meat and fur, make the tools, heal wounds, help with births, praise and sacrifice to the gods and spirits (lets assume they do, most if not all native tribes do so), think about neighbour tribes, inner rivals, mating ... so I am basically just nitpicking that not EVERY intellectual capacity avaiable did go to hunting ..
> Collectively, it's a level of intellectual effort that humanity has likely never brought to bear on any other problem besides, perhaps, farming.
I mean, if you are measuring in terms of brain cycles, perhaps. But huge amounts of these brain cycles were wasted because people lived in small tribes and information decayed quickly in space and time, requiring everyone to continually re-invent things. And the detailed knowledge for hunting one type of animal in one region was not particularly applicable to other animals in other regions, so these are to a large extent just different problems.
IIRC, in the absence of writing, humans had great oral memory. Not only that but they used other mental tricks. EX: Aborigines connecting myths to places in terms like "... And this is where angry bear slept for three days. The water here is still poisonous today from his angry urine..." and so on.
I would say it's more precarious than "modern knowledge" but we haven't really tested the longevity of tech civilization. There are still tribes in Siberia who tell legends of the hunter of the sky tracking the great deer. The "problem" is that they're talking about a set of constellations that were last visible 20000+ years ago. If disaster strikes, how many mediums will be rendered useless (floppies, CDs, lithograph, tapes, etc.)?
That's true, but I suspect all humans needed to wipe most of these animals out was the invention of the spear. There's a difference in what humans hunt compared to most animals. Large healthy animals are quite dangerous, as anyone who's been kicked by a horse can attest, so often their predators are limited to the sick or otherwise vulnerable ones, limiting the population damage they can cause.
Humans can throw a bunch of spears at the biggest thing they can find and follow it until its injuries to do it in. That's great from the perspective of being able to get a lot of food, but not so great in that you're killing off the healthy breeding population.
It really is. Our ability to sweat to shed heat, our slow but incredibly sustainable pace, and our intelligence make us amazing hunters. We're not just pack hunters, we're able to communicate and create complex plans. And in the end, the endurance we have is unmatched in the animal kingdom.
I completely agree. It’s super fascinating to think what other skills/practices that reasoning applies to as well (nutrition stands out the most to me).
That being said, I don’t think your final comment is true (minus the part about farming) due to scale. Sure early humans spent just about all of their effort on hunting, but there weren’t many humans back then. Nowadays we spend much less effort on a given task, but because that effort is distributed amongst billions and billions of people we end up collectively putting in even greater amounts of effort than was likely possible in ‘early human history’.
This is incorrect based on Harari's book: Sapiens. Megafauna in Australia/America didnt have time to evolve, when humans migrated there. While, megafauna in Africa/Asia evolved with humans, so they learnt to survive.
Excerpt from the chapter - Guilty as Charged:
"Various human species had been prowling and evolving in Afro-Asia for 2 million years. They slowly honed their hunting skills, and began going after large animals around 400,000 years ago. The big beasts of Africa and Asia learned to avoid humans, so when the new mega-predator – Homo sapiens – appeared on the Afro-Asian scene, the large animals already knew to keep their distance from creatures that looked like it. In contrast, the Australian giants had no time to learn to run away. Humans don’t come across as particularly dangerous. They don’t have long, sharp teeth or muscular, lithe bodies. So when a diprotodon, the largest marsupial ever to walk the earth, set eyes for the first time on this frail-looking ape, he gave it one glance and then went back to chewing leaves. These animals had to evolve a fear of humankind, but before they could do so they were gone."
Interesting, but it raises the question of why the global extinction didn't happen before. Was there a sudden improvement in human hunting techniques? Or did they stay the same, but the added factor of climate change made it possible for the two of them together to do it, or what?
the last ice age peaked about 21k years ago and ended about 11.5k years ago. Humans have been around for about 200k years, so it probably took some time 'getting on its feet' and reaching critical mass with the ending of the ice age to cause a global impact.
i myself do think we played a larger role. Woolly mammoths actually survived till about 4000 years ago by being in the most remote islands possible. To me, its like something you would see if there was some sort of zombie apocalypse and the last humans only survived in some remote island, far far away from land. Eventually, humans did reach that island, to which the mammoth immediately died off. Though climate change probably played a role, and could have been the primary one, I don't feel it was.
"Mammals went extinct as humans expanded, and they went extinct in areas where the climate was stable but humans were new."
That squares with something I think I read in Guns, Germs, and, Steel, which was that the reason African megafauna like elephants, lions, etc. survived to this day is that they co-evolved alongside humans to the point that they knew to be afraid of the puny little buggers. Meanwhile a 2-ton giant marsupial in Australia had no reason to fear and evade the new bipedal neighbors, or so it thought...
When we go to a museum and see skeletons or life-size models of Pleistocene megafauna, we tend to assume these animals behaved just like the wild animals of today: wary, elusive, and ferocious if cornered. Then we consider the size-difference and shudder.
However, extinct megafauna may have behaved differently. The wild animals of today are the product of tens of thousands of years of intense selection pressure from humans. It's possible that a Mammoth behaved less like an African elephant and more like a Dodo. i.e. Humans migrating into areas where humans were previously unknown may have encountered animals that didn't view them as threats and which did not evade pursuit or defend themselves as modern wild game does.
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[ 3.1 ms ] story [ 85.5 ms ] threadThese are scientists who probably have some idea of how to measure variance. You're some rando on the internet shooting from the hip. ¯\_(ツ)_/¯
Here's the paper, go wild: https://www.jstor.org/stable/43601643
This repurposed quote from the raiders of the lost ark might also work:
"I assure you ... We have top men working on it!"
"Who?"
"Top. Men."
I just get triggered at low-effort skepticism. Tomsaga read the word "stable" and assumed it meant "absolutely stable", and didn't ask himself "huh, I wonder if the pop-sci article is masking a more complicated concept with an easy-to-digest concept".
To get more into the climate stability: What they're doing is measuring the difference in temperature and precipitation between the Last Glacial Max and the Last Interglacial. And the maps don't even have `0` in their range, they have a small number but not zero. So yes, climate wasn't stable, but they were able to measure "how stable" it was. (Pages 1-3 in the paper.)
In contrast, when it comes down to John Q. Internet vs a scientist with relevant expertise, I think it's a reasonable heuristic to think the scientist is more likely to be correct.
IMO the downvotes were more related to the delivery than the content.
[1]http://www.pnas.org/content/112/12/3835
If the discussion was "who is more likely to be right", well, that's a different matter and I'd agree with credentials. But that's not an interesting discussion really.
Somehow, I doubt eating their meat is a healthy thing to do, even when cooked.
EDIT: turns out that the BBC documentary I got that from has outdated information:
> Although previous studies proposed that Komodo dragon saliva contains a variety of highly septic bacteria that would help to bring down prey, research in 2013 suggested that the bacteria in the mouths of Komodo dragons are ordinary and similar to those found in other carnivores.
https://en.wikipedia.org/wiki/Komodo_dragon#Saliva
Collectively, it's a level of intellectual effort that humanity has likely never brought to bear on any other problem besides, perhaps, farming. As such, it's perhaps no surprise that early humans were spectacularly successful at hunting so many of even the largest and most fearsome animals to extinction.
I mean, if you are measuring in terms of brain cycles, perhaps. But huge amounts of these brain cycles were wasted because people lived in small tribes and information decayed quickly in space and time, requiring everyone to continually re-invent things. And the detailed knowledge for hunting one type of animal in one region was not particularly applicable to other animals in other regions, so these are to a large extent just different problems.
I would say it's more precarious than "modern knowledge" but we haven't really tested the longevity of tech civilization. There are still tribes in Siberia who tell legends of the hunter of the sky tracking the great deer. The "problem" is that they're talking about a set of constellations that were last visible 20000+ years ago. If disaster strikes, how many mediums will be rendered useless (floppies, CDs, lithograph, tapes, etc.)?
Humans can throw a bunch of spears at the biggest thing they can find and follow it until its injuries to do it in. That's great from the perspective of being able to get a lot of food, but not so great in that you're killing off the healthy breeding population.
They can just jog after a wildebeest for 8 hours until it overheats, and then they can throw rocks at its head.
That being said, I don’t think your final comment is true (minus the part about farming) due to scale. Sure early humans spent just about all of their effort on hunting, but there weren’t many humans back then. Nowadays we spend much less effort on a given task, but because that effort is distributed amongst billions and billions of people we end up collectively putting in even greater amounts of effort than was likely possible in ‘early human history’.
You leave out the human pursuit which has occupied most of our intellectual and physical resources since we first fashioned tools: war.
Excerpt from the chapter - Guilty as Charged: "Various human species had been prowling and evolving in Afro-Asia for 2 million years. They slowly honed their hunting skills, and began going after large animals around 400,000 years ago. The big beasts of Africa and Asia learned to avoid humans, so when the new mega-predator – Homo sapiens – appeared on the Afro-Asian scene, the large animals already knew to keep their distance from creatures that looked like it. In contrast, the Australian giants had no time to learn to run away. Humans don’t come across as particularly dangerous. They don’t have long, sharp teeth or muscular, lithe bodies. So when a diprotodon, the largest marsupial ever to walk the earth, set eyes for the first time on this frail-looking ape, he gave it one glance and then went back to chewing leaves. These animals had to evolve a fear of humankind, but before they could do so they were gone."
i myself do think we played a larger role. Woolly mammoths actually survived till about 4000 years ago by being in the most remote islands possible. To me, its like something you would see if there was some sort of zombie apocalypse and the last humans only survived in some remote island, far far away from land. Eventually, humans did reach that island, to which the mammoth immediately died off. Though climate change probably played a role, and could have been the primary one, I don't feel it was.
That squares with something I think I read in Guns, Germs, and, Steel, which was that the reason African megafauna like elephants, lions, etc. survived to this day is that they co-evolved alongside humans to the point that they knew to be afraid of the puny little buggers. Meanwhile a 2-ton giant marsupial in Australia had no reason to fear and evade the new bipedal neighbors, or so it thought...
However, extinct megafauna may have behaved differently. The wild animals of today are the product of tens of thousands of years of intense selection pressure from humans. It's possible that a Mammoth behaved less like an African elephant and more like a Dodo. i.e. Humans migrating into areas where humans were previously unknown may have encountered animals that didn't view them as threats and which did not evade pursuit or defend themselves as modern wild game does.