Humans Played Key Role in Megafauna Extinctions, New Research Confirms

Pantheraman

Well-Known Member
"Across the last 50,000 years land vertebrate faunas have experienced severe losses of large species (megafauna), with most extinctions occurring in the Late Pleistocene and Early to Middle Holocene. Importantly, this extinction event is unique relative to other Cenozoic (the last 66 million years) extinctions in its strong size bias. For example, only 11 out of 57 species of megaherbivores (body mass over 1,000 kg) survived to the present. Debate on the causes has been ongoing for over two centuries."

Humans Played Key Role in Megafauna Extinctions, New Research Confirms | Sci.News

At first glance, this might look reliable. But looking at the list of authors of this paper, it turns out to be as reliable as Quora. One of the authors, Erick Lundgren, is an advocate for not culling invasive species and keeps claiming that invasive ungulates have replaced extinct megafauna. This study is simply nothing more than them trying to justify invasive ungulates.
 
I've always been skeptical of the claims that humans were the primary drivers of extinction of prehistoric megafauna. It just seems unlikely to me that humans could have wiped out widespread continental species with such a low level of technology, and the fact that it lines up so well with a period of major and relatively sudden climatic shift would certainly seem to suggest a different culprit.
 
A paper confirming what is by far the likeliest outcome that most people already accepted.
Then I suppose we should introduce elephants into North America to replace mammoths because humans supposedly wiped out mammoths, and we should introduce lions to North America to replace American lions because humans supposedly caused their extinction, and we shouldn't cull feral horses because they've supposedly replaced extinct horses from the Pleistocene.

This paper is simply nothing more than so-called "compassionate conservationists" trying to justify current invasive ungulates by saying "We humans killed off the ice age megafauna, so we must preserve introduced ungulates because they're replacing extinct megafauna." A big conflict of interest if you ask me.
 
Then I suppose we should introduce elephants into North America to replace mammoths because humans supposedly wiped out mammoths, and we should introduce lions to North America to replace American lions because humans supposedly caused their extinction, and we shouldn't cull feral horses because they've supposedly replaced extinct horses from the Pleistocene.

This paper is simply nothing more than so-called "compassionate conservationists" trying to justify current invasive ungulates by saying "We humans killed off the ice age megafauna, so we must preserve introduced ungulates because they're replacing extinct megafauna." A big conflict of interest if you ask me.
Literally where did I even remotely suggest this, don't put words in my mouth.

There has been numerous debates on this forum around this and every time, multiple members have given you evidence over why a climate based extinction theory is outdated or not as relevant as a human one and you won't budge. It seems like this is because you have a grudge with these "compassionate conservationists"? Their existence does not mean the human theory is wrong I hope you realise. The fact that I reply with something completely unrelated to this and you immediately jump on to this again says a lot.
 
Literally where did I even remotely suggest this, don't put words in my mouth.

There has been numerous debates on this forum around this and every time, multiple members have given you evidence over why a climate based extinction theory is outdated or not as relevant as a human one and you won't budge. It seems like this is because you have a grudge with these "compassionate conservationists"? Their existence does not mean the human theory is wrong I hope you realise. The fact that I reply with something completely unrelated to this and you immediately jump on to this again says a lot.
What evidence? All I remember is you guys simply told me why you think I was wrong rather than actually showing me evidence. Show don't tell as the saying goes. Due to that, of course, I didn't budge.


I'm not saying "compassionate conservationists" means the overkill hypothesis is wrong, I'm stating that their involvement in this study makes it a lot less reliable due to their conflict of interest.

The rest of the stuff was my way of asking how you felt about pleistocene rewilding since you believe in the overkill hypothesis.
 
The rest of the stuff was my way of asking how you felt about pleistocene rewilding since you believe in the overkill hypothesis.
That's something you clearly have to work on then considering rather than a simple question asking her on it (which isn't really related to the thread topic), you immediately accuse her of believing so and larking on your own emotion filled rhetoric, also I believe the overkill hypothesis is actually different to just humans playing a major factor in the extinction of megafauna, considering humans also display major ecological shifts, such as the creation of fire regimes and other changes to the surrounding ecosystem rather than just 'overkilling'.
 
I've always been skeptical of the claims that humans were the primary drivers of extinction of prehistoric megafauna. It just seems unlikely to me that humans could have wiped out widespread continental species with such a low level of technology, and the fact that it lines up so well with a period of major and relatively sudden climatic shift would certainly seem to suggest a different culprit.

They didn't do it alone, climate did help, but without humans there is no reason to suppose why they couldn't have survived yet another climatic shift (having survived dozens). Being skilled hunters that in places could change the landscape with fire isn't exactly "low technology" for a giant ground sloth. I am not going to reiterate all arguments, but I suggest you read some reliable literature....

It is far too coincidental that whenever people arrive at a new landmass (be it New Zealand <1000 years ago or North America >10.000 years ago), the megafauna quickly disappears.


What evidence? All I remember is you guys simply told me why you think I was wrong rather than actually showing me evidence. Show don't tell as the saying goes. Due to that, of course, I didn't budge.

Then maybe you should read those discussions again, as plenty of examples were given in the debates with you as to why you are wrong. That it doesn't conform with your beliefs is something else entirely.
 
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@lintworm @Fallax @WalkingAgnatha

Alright, since you're proponents of the overkill hypothesis who insist anyone who disagrees with the hypothesis is completely wrong then I must wonder. What do you guys think of using Pleistocene rewilding to justify invasive species? Because the truth of the matter is, the overkill hypothesis does nothing but add fuel to the fire of "compassionate conservation". Any layman who hears their rhetoric will probably be more incentivized to preserve invasive species such as feral horses and introduce new ones.
 
@lintworm @Fallax @WalkingAgnatha

Alright, since you're proponents of the overkill hypothesis who insist anyone who disagrees with the hypothesis is completely wrong then I must wonder. What do you guys think of using Pleistocene rewilding to justify invasive species? Because the truth of the matter is, the overkill hypothesis does nothing but add fuel to the fire of "compassionate conservation". Any layman who hears their rhetoric will probably be more incentivized to preserve invasive species such as feral horses and introduce new ones.
Once again putting words in people's mouthes for no reason, first off overkill hypothesis is still very different to simply megafaunal extinctions with major human influences (ie. rapid shifts in ecology/habitat through fire and other changes as well as increased competition and of course hunting pressure). You haven't stated anything against the theory except your view of it in a political vein, rather than viewing it scientifically and rationally you for some reason seems to think it only ''adds fire"?
Yet they're entirely different, as the ecological difference between living '''congeners''' and extinct species is simply too far!! Compassionate conservationists are using the role of humans in megafauna extinctions to justify their fringe beliefs and then people who deny any role of humans in megafauna extinction using the fact that this was written by compassionate conservationists as a gotcha.
eg."Other introduced megafauna are phylogenetically distinct from any prehistoric megafauna but still share trait resemblance, for example for Australia there is no species more ecologically similar to the extinct marsupial Palorchestes azael than the introduced dromedary Camelus dromedarius, based on available functional traits (Lundgren et al. 2020)."
The problems with this are clearly obvious even ignoring all the ways in which their ecology probably doesn't line up (eg the MAJOR difference between hooved & non-hooved mammal, soil compaction...), and the fact that Australian ecology has developed and changed since then, they have NO overlap in distribution or habitat whatsoever [Palorchestes being from wet temperate forests of coastal SE Aus].
So no, I do not 'believe' in compassionate conservation because it doesn't take into account the existing ecology and mostly draws upon random living existing species which do not 'fulfill' the role of megafauna and ignores the current state of the ecology and the importance of human management in them (eg maintaining of fire regimes in Aus & NA) because of the idea of returning to some past 'ideal' 'devoid of humans' which isn't really attainable our preferrable at our current state.
 
I believe that 'proxy megafauna' is a flawed concept in many concepts I have seen. Asiatic Elephants and mammoths/mastodons are species adapted for rather different habitat and climate; the latter which doesn't really exist anymore. And also that year-round Asiatic elephants live in environment of plentiful food supply; and my thoughts on them surviving food-scarce winter is doubtful. But what I have better hope for is a similar idea, but not quite so far-flung so to put.
I recall about a year ago now I visited the Knepp estate in Sussex [a story I think I have told round here before]; and there they have older breeds which work as proxy species for wild grazers; many which are now extinct. The reserve has several living species of deer as wild animals; and also has longhorn cattle, as proxy for aurochs - Exmoor pony, as proxy for tarpan - and Tamworth pig - as proxy for wild boar; which is still alive today but considered a 'dangerous animal' under UK law, which hinders reintroduction*. These animals have now been reintroducees there for the better part of 20 years; [the area was once a swathe of unsuccessful farmland] and there they have seen promising result - high-quality areas of scrubland, and the proliferation of many species struggling in most other areas of the country.
In a sense it offers a glimpse as to what the landscapes of the UK may have looked like long ago; and regardless of authenticity the proliferation of native wildlife is surely a good thing. But I think therein lies the crux - these aren't totally obscure or died out lineages that have been reintroduced; merely close relatives of what was. This helps keep their ecological impact in less doubt than say a camel for a similarly-sized herbivore with different feeding techniques.
I think if anything this is what is most promising - and I think the same of water-buffalo reintroduction in Ukraine.

*that is to say, some have, illegally, reintroduced wild boar into areas of the UK. At which point they become of no problem to the law whatsoever. So there.
 
So no, I do not 'believe' in compassionate conservation because it doesn't take into account the existing ecology and mostly draws upon random living existing species which do not 'fulfill' the role of megafauna and ignores the current state of the ecology and the importance of human management in them
I just want to point out that "compassionate conservation" and "Pleistocene rewilding" are two completely different things. Pantheraman just consistently conflates them. All compassionate conservation is, is the belief that every individual animal has the same value and that one animal shouldn't be killed for the benefit of either another species or an ecosystem. A person can be a proponent of both ideas, but they are not the same thing at all.
 
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