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Comment by tkel | Hacker News Reader

With regards to the Late Pleistocene extinction overkill hypothesis that you are referring to, your information is out of date, more recent evidence suggests that humans played only a minor or incidental role, with climate change (the end of an ice age), and habitat restructuring being the primary drivers.

I don't think you understand what the noble savage trope is. I'm commenting on the development of indigenous human societies in the Americas. The vast majority of them were ecologically compatible. This is not a commentary on the morality of individuals. To take the Mexica empire as an example, they were not a moral civilization by our standards (neither were the Spanish colonizers), and they had an over-reliance on corn and obsidian, but other than that they survived in a way that did not stress or extinguish or destabilize the surrounding ecology.

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I do not quite buy your arguments, and I am skeptical of several claims that you make. Without specific sources, it is more difficult for me to contest them, though I will not request sources.

From your perspective, what caused the extinction of several megafauna/large species of animals after the arrival of Aboriginals in Australia?

That's mistaking correlation for causation. I don't have proof, but let's consider an alternative: that the climate change that made those areas newly-hospitable to humans made them inhospitable to megafauna. Can you falsify "all of the species were subject to the same environmental shift" before you jump to "arriving humans hunted them all to extinction"?

(And I recognize the parallels to some unsavory arguments, and would like to point out that the evidence regarding contemporary man-made climate change is strong and sound. But that's with industrialization and a couple orders of magnitude more people on the planet.)

> That's mistaking correlation for causation. I made no such mistake. Though, I was not aware of there being competing theories regarding the significant number of extinct megafauna species around the gross time interval of the arrival of Aboriginals to Australia and Tasmania, my apologies. There are two competing set of theories, namely human-caused ones and natural-climate-caused ones, as far as I can tell. I was only aware of or could only remember the first type of theory.

For a clearer and possibly more settled and agreed upon example: From your or the other commenter's perspective, what caused the extinction of Moa after the arrival of Maori in New Zealand? Some claims that the Moa went extinct within 100 years of human settlement, and that it had a large population before that

https://www.ebsco.com/research-starters/zoology/maoris-hunt-...

>The extinction of all moa species occurred relatively swiftly, between 1380 and 1440, making it one of the most rapid extinctions in history. Contributing factors included habitat destruction through woodland burning, the introduction of non-native predators such as dogs and rats, and the birds' natural life cycle, which featured low egg production.

It's not a good example to use to prove your contention, because it's an outlier, and because it involved the use of technology that wasn't necessarily available to other incidences of megafauna extinction.

I think if you consider that single instance it is mistaking correlation for causation.

However, it happens every time, with a lag. In different climates and environments. When humans expanded out of Africa, spread out over Eurasia, reached North America, South America, Australia, new Zealand extinction of megafauna always followed.

We know that there was large scale hunting and humans are highly effective hunters. Hunting megafauna is the easiest available food source for a pre-industrial society until they get to the point where there is too little megafauna left (and changes, eventually including farming follow). Unlike large carnivores we are not dependent on hunting megafauna so our human numbers do not drop when they are in short supply.

It's still mistaking correlation for causation, even when considering multiple instances, if you can't describe an unfalsifiable mechanic as the cause.

There are two problems here:

1) It hasn't actually happened every time. Elephants, hippopotamuses, large whales, polar bears, grizzly brown bears, certain large bovines, and moose still exist.

2) Extinctions of megafauna are distributed across a time delta from human arrival. I don't know for sure, but I would wager that that delta doesn't necessarily correlate with date (as a proxy for technological development).

That is to say, "humans arrive -> everything big dies" is not so cut-and-dry a rule. It should be clear that other factors are involved.

I'll suggest a third option: humans hunt megafauna to extinction in the presence of conditions that favor such behavior - perhaps climatic, geographic, and/or cultural. So, it happens. But it doesn't always happen.

For the purposes of this conversation, I don't think you've proven the original contention wrong, which was that indigenous people in the Americas found a niche which made their presence and behavior sustainable over long periods of time. If your evidence is the total extinction of American megafauna, then you would be forced to admit that you were incorrect. In fact, you potentially argue for the opposite: in clearing some megafauna but sparing others, humans did indeed carve out a potentially sustainable ecological niche, which their continued presence helps to prove was sustainable. At least, until culturally disparate humans arrived.

A significant number of mega fauna species is hunted to extinction whenever humans arrive.

> If your evidence is the total extinction of American megafauna

The evidence is the extinction of most American megafauna species.

> In fact, you potentially argue for the opposite: in clearing some megafauna but sparing others, humans did indeed carve out a potentially sustainable ecological niche, which their continued presence helps to prove was sustainable.

Humans have continued to survive everywhere, so that is evidence the the presence of humans everywhere has been sustainable.

The comment making the claim about indigenous societies in the Americas is that they are "ecologically compatible". They are compatible with an ecology they altered. This is, again, true everywhere. You might argue that industrialisation has changed this as a (relatively) stable state is not reached because of continuing rapid change, but it was true before industrialisation.

> I'll suggest a third option: humans hunt megafauna to extinction in the presence of conditions that favor such behavior - perhaps climatic, geographic, and/or cultural. So, it happens. But it doesn't always happen.

I have two objections to that:

1. Its not all megafauna, it is most. Some species can survive humans. 2. The extinctions have happened across many different climates and cultures and on every continent and many islands.

It is not proved beyond doubt that humans have always caused extinctions, but the pattern is very consistent, which makes it by far the most likely explanation. Even where hunting is not the direct cause, many things humans do (such as agriculture) will destroy their habitats.

Where humans did not arrive until much later than most places (e.g. in places such as New Zealand or Madagascar) megafauna survived until after they did, and were then gone with a few hundred or a few thousand years.

What does ecologically compatible mean to you? Because it is expressed as some kind of choice.

Were the japanese naturally compatible in the distant past? And if in the end this ecological compatibility just so strongly correlated with development and ability than what boundary does it actually refer to?

Relax. I don’t think the OP means there’s some genetic flaw in Europeans that makes them ecologically imbalanced by nature.

They’re saying that a lot of indigenous culture and practice was more sustainable. This may be for various reasons, and isn’t true only of American indigenous people but almost certainly people in Japan, India, Australia, etc., where urban civilization that depended on large scale agriculture didn’t take hold.

This is, if you see it, only evidence that there’s no inevitable path for progress and development for our species. We have the ability to look back, see how different parts of the world handled their engagement with their environment, when and where that degraded, and make changes, proving that none of this is inherent to any part of our species, but rather cultural and social structures that emerged for a bundle of reasons.

> They’re saying that a lot of indigenous culture and practice was more sustainable

Europe seems very sustainable to me, people have been living there for thousands of years and are still thriving. Why do you say Europeans doesn't have sustainable agriculture? They wouldn't have been able to become so dominant otherwise.

Because “Europe” hasn’t been one thing for any length of time.

And what even does “become so dominant” mean? You do know evolution isn’t some straight accumulative equation, right? Dominance means all things done are good?

Dominance over what time scale? Sustainable over what timescale?

The sad fact is, for any society, short term dominance causes long term instability. That multiplies a lot when you spend hundreds of years accumulating land and control and wealth. It’s sure sweet while the going lasts. Then what happens when there’s pushback?

We can’t fully answer that question yet. We’re living through that post colonial era of Europe.

My hope is Europe thrives. I doubt it will if it goes back to its old extractive practices. Thankfully, most governments in Europe seem to have moved past that mentality.

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