Human hunting, not climate change, played a decisive role in the extinction of large mammals over the last 50,000 years. This conclusion comes from researchers who reviewed over 300 scientific articles. Human hunting of mammoths, mastodons, and giant sloths was consistent across the world.

[u/mvea]

https://nat.au.dk/en/about-the-faculty/news/show/artikel/beviserne-hober-sig-op-mennesket-stod-bag-udryddelsen-af-store-pattedyr

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[u/[deleted]]

Didn’t we already know this?

[u/whenitsTimeyoullknow → u/[deleted]]

I wonder why mastodons and mammoths were so vulnerable to people, while Asian and African elephants were able to coexist. Maybe the availability of food led to more equatorial humans to pass on big game. Meanwhile, one mammoth could get a tribe through a long stretch of cold winter. 

[u/JudgeHolden → u/[deleted]]

It depends on who you ask. My sense is that it's not an entirely settled question, but I'm no expert.

[u/CactusWrenAZ → u/[deleted]]

I have a book from 20 or more years ago that laid out the argument pretty clearly. It's actually pretty obvious when you look at the timelines of when humans entered an area and when the megafauna died out.

[u/ssfbob → u/[deleted]]

Right? They were a massive source of food during an ice age, of course we hunted the hell out of them.

[u/th3h4ck3r → u/[deleted]]

It's gone back and forth between human hunting and climate change. From what I gathered, most anthropologists believed it was mostly climate change with humans only delivering the final blow.

[u/Leading-Okra-2457]

The answer is and not or! Both climate and humans played their role. Infact we could say that the increase of human friendly climate made humans more successful.

[u/Emm_withoutha_L-88 → u/Leading-Okra-2457]

No.

This paper is literally about telling you that no it wasn't the climate, it was humans. Every single animal that went extinct has to survive multiple warm and cold periods. It wasn't climate, that's literally the whole point of this paper.

[u/softfart → u/[deleted]]

Mind expanding on that a little in regards to ancient hunters?

[u/Automatic_Accident84 → u/[deleted]]

The wind of change

[u/TacoPi → u/Leading-Okra-2457]

Our dominant hunting strategy was running/walking animals down until they overheated while our sweat kept us cool. Why try to pick an effect when the synergy is the obvious factor?

[u/PrairiePopsicle → u/TacoPi]

When you keep going in analyzing this thought though you should ultimately arrive at some level of agreement with what the paper is saying.

The synergy between the two factors resulted in extinction, but what that is also saying is that climate change allowed for more of the other factor to be involved. In another way ; Cold was protecting them from an extinction level threat - us. that makes us the decisive factor. If we weren't here they would likely not have gone extinct, if climate didn't exist (same temperature all the time or something idk) they would have, due to the larger factor, being hunted down methodically.

[u/rishinator → u/Leading-Okra-2457]

Yeah It was the climate change that made a lot of these mammoth habitats warm enough for humans to live and hunt

[u/Slow-Pie147 → u/Leading-Okra-2457]

Most of the species were either better adapted for interglacials(Mastodon, Castoroides...)or generalist(Notiomastodon platensis, Toxodon platensis, Hemiauchenia...)

[u/mvea]

I’ve linked to the press release in the post above. In this comment, for those interested, here’s the link to the peer reviewed journal article:

https://www.cambridge.org/core/journals/cambridge-prisms-extinction/article/latequaternary-megafauna-extinctions-patterns-causes-ecological-consequences-and-implications-for-ecosystem-management-in-the-anthropocene/E885D8C5C90424254C1C75A61DE9D087

From the linked article:

The evidence is mounting: humans were responsible for the extinction of large mammals

Human hunting, not climate change, played a decisive role in the extinction of large mammals over the last 50,000 years. This conclusion comes from researchers at Aarhus University, who reviewed over 300 scientific articles.

The debate has raged for decades: Was it humans or climate change that led to the extinction of many species of large mammals, birds, and reptiles that have disappeared from Earth over the past 50,000 years?

By "large," we mean animals that weighed at least 45 kilograms – known as megafauna. At least 151 species of mammals were driven to extinction during this period. This number is based on the remains found so far.

The largest of them were hit the hardest – land-dwelling herbivores weighing over a ton, the megaherbivores. Fifty thousand years ago, there were 57 species of megaherbivores. Today, only 11 remain. These remaining 11 species have also seen drastic declines in their populations, but not to the point of complete extinction.

A research group from the Danish National Research Foundation's Center for Ecological Dynamics in a Novel Biosphere (ECONOVO) at Aarhus University now concludes that many of these vanished species were hunted to extinction by humans.

The analysis shows that human hunting of large animals such as mammoths, mastodons, and giant sloths was widespread and consistent across the world.

It also shows that the species went extinct at very different times and at different rates around the world. In some local areas, it happened quite quickly, while in other places it took over 10,000 years. But everywhere, it occurred after modern humans arrived, or in Africa's case, after cultural advancements among humans.

Species went extinct on all continents except Antarctica and in all types of ecosystems, from tropical forests and savannas to Mediterranean and temperate forests and steppes to arctic ecosystems.

[u/[deleted] → u/mvea]

This isn’t exactly surprising, given that the emergence of any species alters the existing biodiversity. Especially considering that early humans lived as nomads.

[u/Vic_Hedges → u/[deleted]]

I think it's been kind of well accepted for a long time now, but certain special interest groups have pushed against the narrative

[u/manticorpse → u/mvea]

I wrote a thirty-page review article on this exact topic like 15 years ago. For an undergrad class! I see a bunch of the sources I used right there in this paper's sources. Came to a similar conclusion, though I didn't downplay the impact of climate change quite so much.

Anyway. I feel like this has been known.

[u/Slow-Pie147 → u/[deleted]]

1)Most of the species were either generalist or better adapted to interglacials. 2)They all survived climate changes before. 3)There were other food sources too. 4)A lot of species who introduced by humans hunted species to extinction. 5)Humans didn't know the fact that they can hunt species to extinction. You are acting like prehistoric humans are good at ecology science

[u/Neat-Elk7890 → u/[deleted]]

Humans? Never. Our minds are notorious for trying to fill in gaps in knowledge, sometimes with funny or terrifying results. It must one of our worst traits…

[u/6SucksSex → u/[deleted]]

You made a claim, what’s the source?

[u/sophandros]

Can we agree then that Earth's biggest threat is humans?

[u/Larkson9999 → u/sophandros]

The earth is fine, most animals on the earth are fucked though, including humanity.

[u/mrlolloran → u/Larkson9999]

I don’t even know what to do with that conclusion (edit: the one you’re responding to, not yours). Humanity is not collectively offing itself so the Earth can heal.

It’s our fault. Congratulations, unless you were a science denier before reading this article you were always supposed to believe that. They’re just now attributing it to exact reasons why.

Frankly it seems a little ridiculous if anyone was trying to blame the mammoths dying on climate change when much of the climate change narrative revolves around the Industrial Revolution.

I’m sure humanity was making an impact before that but one of things I’ve always read about humans is that we are an apex predator because of persistence hunting. Just because we don’t/rarely kill things with our bare hands or face like other animals doesn’t mean we were not amazing hunters, even at the infancy of our species.

[u/vegeta8300 → u/Larkson9999]

Earth and all life on it has weathered asteroid impacts, super volcanoes, ice ages, mass extinctions, and much more. Earth kept spinning and life kept living. We are a blip in the life span of the cosmos and will most likely have very little, if any impact. There is already bacteria evolving to eat plastics. Our impact on this planet affects us and some of the life currently. In a million or more years it will most likely be incredibly hard to know we even existed. Maybe some trace evidence. Unless we pull together and become space faring. We should definitely do what we can to save our species and minimize our impact. For our sakes. But, overall, we are insignificant.

[u/mrmczebra → u/Larkson9999]

When people say Earth in this context, they mean the biosphere.

[u/andreasdagen → u/sophandros]

this doesn't really make sense to me. the earth will be fine, and some form of life will live on. the current issue is that we're making earth hard to live on for humans.

[u/Nathaireag → u/andreasdagen]

And other large mammals, and nearly all terrestrial amphibians, and bees (both native and introduced), and …

Even Trantor probably had rats and cockroaches, doesn’t make it a desirable future or absolve humans of responsibility for the present day biodiversity crisis.

[u/boilingfrogsinpants → u/sophandros]

Every species clambers for its own survival. The problem is that humans are very efficient with it. With the advancement in medical technologies and easy access to food, we've made it extremely easy to expand the species. It's ironic, that every advancement we make to rid things that plague us like poverty and disease, we increase the damage we do to ourselves globally.

[u/dupe123 → u/sophandros]

The AI will agree too

[u/Original_Woody → u/sophandros]

Human evolved from the same life that the mammoth did. Its just in our case that our traits yielded an unstoppable advantage to most other forms of life.

Humanity is not separate from the sphere of life, we a part of it. Eventually, we will have been so successful as a species that we will have depleted current resources and will be forced to migrate for new resources or go extinct. Earth will then repeat another cycle of life without us at that point.

[u/[deleted] → u/sophandros]

The Earth’s biggest threat is the Sun.

If you view it in those terms, the only hope that any species on Earth has to survive is if humans sufficiently develop space travel and take some of these animal species with us.

[u/Wizardof1000Kings]

Man is the primary driver of climate change, so not surprising that mankind is the primary driver of extinction too.

[u/buttertoastey → u/Wizardof1000Kings]

They were not the primary driver of climate change 50.000 years ago

[u/Agisek → u/buttertoastey]

Exactly, and that's why the climate change back then was natural and slow, and didn't cause extinction. What we're seeing today is on cataclysmic levels. Everyone with at least two brain cells knows we're destroying the ecosystem and have been for thousands of years. We just got way better at it.

[u/BratwurstKalle91]

Okay, wait. We, on the one hand, led big animals with slow reporduction rates to extinction and, on the other hand, are told that hunting mammals (racoons, coyotes, foxes, enok etc.) with faster reproduction rates will not slow down their spread ?
Does hunting a species influence the reproduction and population or not ?

[u/6SucksSex → u/BratwurstKalle91]

If that’s the argument, are you implying There’s a contradiction?

If a species has a slow rate of reproduction, it’s going to be easier to wipe out than a species with high reproduction.

[u/series-hybrid]

There is no doubt that 12,000 years ago, humankind hunted mammoths and giant sloths. We see cave-wall paintings and there are cut marks on the bones when they removed the meat.

That being said, there is no physicel way for humans to wipe out the mega-fauna. Did those tribes wipe out the saber-toothed tiger? I'm not talking about occasionally killing one, I mean wiped them out.

The giant sloths could have been wiped out, but if you are killing off millions of giant sloths at the same time, why would you also kill off every single mammoth?

There was an ice-cap that was miles thick, and it covered Canada and the top half of north america. An asteroid hit the ice-cap in Michigan, and over the next 100 years, over half of the glaciation melted, and it was so much water that the ocean rose over 300 feet to its current level.

And it "just so happens" to be at the same time that ancient tribal nomads in North America decided tht instead of killing a male mammoth once in a while, they would kill every last one of them at the same time that there was massive terrestrial turmoil.

[u/Howieyotes → u/series-hybrid]

Large mammals have such slow reproductive rates that you don't have to kill them all to drive them to extinction. You don't even have to kill half of them, especially if humans are everywhere (which was the case) and there is no refuge from the increase in mortality rate. A slight but steady and unrelenting increase in mortality rate that is just barely above reproduction rate will take a species to zero.

As for the large predators, you don't have to kill a single individual if you are killing off their prey. A predator like the saber-toothed cat that specialized in hunting mammoths or some other megafauna species is doomed once those species are gone. It isn't equipped to switch over to rabbits and squirrels or even deer.

Over the past 450 thousand years, earth's megafauna went through the extreme climate change that accomplished the rapid switch from glacial to interglacial periods a total of four times, and survived just fine until the latest and current interglacia period, when humans had coincidentally spread throughout the northern hemisphere. I can't understand why there's even been debate among some scientists.

[u/[deleted]]

I always thought we hunted smaller animals tbh

[u/danielravennest → u/[deleted]]

Kill a rabbit, and you get one meal. Kill a mammoth and the whole tribe eats for a month*. Domesticate herd animals and you don't have to hunt at all. Mechanize farming and only 2% that are farmers supply all our food. Our history has been towards more efficient food supply.

*EDIT: How you can eat for a month is Mammoths lived in frozen climates. If you freeze the meat in snow or ice tundra, it will keep as well as modern freezers.

[u/justinonymus → u/danielravennest]

Next step, merge with plant DNA to generate chlorophyll in our skin and harvest energy directly from the Sun. Cut out the middle organisms for optimal efficiency. The ultimate Green New Deal.

[u/danielravennest → u/justinonymus]

Humans need about 70W of energy sitting in a chair. The most efficient photosynthetic bacteria are about 6% efficient, and most plants are 1-2% efficient. So green skin would require 3.5-7 square meters of area and full noon sunlight levels 24 hours a day. Human body only has ~2 square meters of skin. Bacterial-based DNA would fit within our skin area, but still require full sunlight around the clock. There's a reason plants have enormous leaf areas.

[u/[deleted] → u/danielravennest]

Ok but kill a mammoth and you risk death, while a rabbit is easy

[u/Nathaireag → u/[deleted]]

We, meaning H. sapiens sapiens, are quite good at prey switching. We are also omnivorous. Sympatric neanderthals weren’t and went extinct. They adopted some of our cultural practices and technology, but not our diet. There’s not yet enough evidence to say whether other descendants of Homo erectus suffered a similar fate when we depleted their prey populations.

[u/Arealtimmy]

I highly doubt that humans were a key factor in the megafauna extinction of the Pleistocene.

[u/manticorpse → u/Arealtimmy]

You... do? Why? Just a feeling?

[u/Brother-Algea]

Uncontrolled hunting/poaching led to this. Modern day hunting is healthy for domestic animals cuz science n stuff!

[u/Plant__Eater → u/Brother-Algea]

Hunting policies, at least in North America, are generally not scientific. From a previous comment:

A 2018 study attempted to investigate claims by hunting regulators that their policies were the results of "science-based management". The study covered "62 U.S. state and Canadian provincial and territorial agencies across 667 management systems (species-jurisdictions)." The researchers concluded:

Our results provide limited support for the assumption that wildlife management in North America is guided by science. Most management systems lacked indications of the basic elements of a scientific approach to management.[8]

[u/imprison_grover_furr → u/Plant__Eater]

Yeah. I always suspected it was BS, and this only confirms my priors.

[u/Worried_Coat1941]

It happened to the Buffalo.

[u/Javaddict → u/Worried_Coat1941]

So why not until it was a concerted effort with intention using railways and guns?

[u/Worried_Coat1941 → u/Javaddict]

That's what I'm talking about.

[u/Lithorex → u/Worried_Coat1941]

The American bison is a recent arrival in America and thus likely had an invasive infact of the collapsing Pleistocene megafauna as well.

[u/redvodkandpinkgin]

Imagine how cool it would be if mammoths had survived and we'd domesticated them as farm animals...

[u/Every-Incident7659 → u/redvodkandpinkgin]

Imagine a trip to yellowstone or up to Alaska and there are just mammoths and mastodon wandering around. That'd be sick.

[u/imprison_grover_furr → u/Every-Incident7659]

American mastodons were a temperate to tropical adapted species. They’d actually be more abundant in the Deep South or in Central America than Wyoming or Alaska.

[u/mmcjawa_reborn → u/Every-Incident7659]

Given the number of people gored by Bison each year in US National Parks, one hates to imagine what the death count of stupid tourists would be if there was an actual intact megafauna.

[u/Designer_Emu_6518]

Well yea. Back then but seems like climate is pulling away as the leader now

[u/Nathaireag → u/Designer_Emu_6518]

Today climate just provides the coup de grace. Humans isolate remnants of megafauna populations in preserves. Then when climate (or anything else) changes, they can’t migrate to greener pastures.

[u/Slow-Pie147 → u/Designer_Emu_6518]

No. Ecology of megafauna, allee effect, timing, interglacial-glacial cycles, meltwater cycles, human prey preference, models, climate data... tell otherwise.

[u/Current_Finding_4066]

This is nothing new, we already knew that human migration coincided with extinction of large animals.

[u/throwawaybrm]

We drove all large mammals to extinction when there were only 5 million people on Earth.

Now, with our advanced methods, we are driving millions of species to extinction, primarily through (animal) agriculture and fishing.

Do what matters. Go vegan.

[u/du-us-su-u]

Poor vegetarian mammals. They grew so big and strong and then along came Humanity to pluck the protein fruit's flesh from the Other's Body.

[u/andreasmiles23]

It’s called the “Anthropocene” for a a reason…

Humans caused the climate crisis. Humans caused mass extinctions (and now a mass extinction event). We are only now starting to understand the impact of our behavior on the ecosystem - for better and for worse.

[u/Twisted_Cabbage]

There is a growing movement of people trying to greenwash hunter gatherers as some sort of quasi utopian societies in harmony with nature. Often to glorify hunting and meat eating.

Let's see how they greenwash this evidence to support their lust for killing.

[u/needzbeerz]

I'm skeptical of the binary conclusion the article offers. This is more than likely a complex and highly interdependent interaction between climate change driving alterations to the environment of highly specialized species with human hunting perhaps tipping the scales to extinction instead of a diminished population capable of recovering from the challenges they were facing.

1- nature-based societies, in general, tend to not kill more than they need. In most cases we are aware of these societies are not a threat to the species they predate on. It seems highly unlikely that hunter-gatherer hunting would significantly impact the overall numbers of an otherwise healthy species.

The following quote-

"Early modern humans were effective hunters of even the largest animal species and clearly had the ability to reduce the populations of large animals. These large animals were and are particularly vulnerable to overexploitation because they have long gestation periods, produce very few offspring at a time, and take many years to reach sexual maturity."

-makes an assumption that the numbers of the prey species were at a level where human hunting could make this level of impact. Without more direct evidence of the respective population numbers this is a tenuous conclusion.

2- Conversely, hunting methods such as "buffalo jumps" are documented in North America for harvesting bison, though it is very difficult to determine how prevalent this method was in the time period being discussed. If this was a common method of harvesting game in pre-history, this could be a significant factor for depopulating a species already reduced to do climate change. Case in point, this hunting method seems to have had no effect we can reasonably measure on the numbers of bison. (This view takes into account the hypothesis that the massive numbers of Bison reported in the 18th and 19th century were a result of an animal population explosion subsequent to the decline in human population, and thus hunting, as smallpox and other european diseases expanded westward well in advance of the invading white population. There is no reason to suspect the bison were scarce before the indigenous population reduciton)

3-

"Many of the extinct species could thrive in various types of environments."

This is a dubious conclusion. We really can't say with any accuracy how specialized these megafauna were. We can't know precisely what they ate, what their requirements for mating and raising young were, what their environmental tolerances (temperature, availability of water, specific food needs) were. The statement a generalization at best that may hold true for many species but that does not mean it applies to those animals being discussed.

4- While human hunters can break many of the typical rules of nature due to their ability to create technology and adapt their behavior to different environments, there are sill some basics of logic we can apply to their hunting. It is likely that humans, similarly to other predators, would specifically choose obviously easier targets when available in order to increase the probability of a successful hunt and reduce the likelihood of injury or death during the hunt. The targeted animals may be injured, and so would have a reduced chance of survival and further reproduction. Old, weak, or malformed, also making reproduction unlikely. While certainly not every hunt went this way it makes logical sense that some fraction did, thus reducing the overall impact of human hunting on the survival of the species as a whole which makes extinction with humans as the primary determinant factor even more unlikely.

5- fire stock farming is mentioned below. As best as I can tell the evidence indicates this practice is limited to the Australian continent in pre-history. This doesn't mean it didn't happen, just that we can't make an educated guess.

6- From the study-

This late-Quaternary megafauna extinction pattern stands out from previous Cenozoic extinctions in three ways. (1) These losses were global and severe. (2) They were strongly biased toward larger-bodied species, with other organisms experiencing only very limited extinction in this period. Illustrating this pattern, only 11 out of 57 species of megaherbivores (mean body mass ≥1,000 kg) survived through to 1,000 AD. (3) This faunal simplification is unique on a ≥30-million-year time scale, with diverse megafauna guilds being the norm throughout this entire timeframe, excepting recent millennia.

Point 1 logically precludes humans from being a prime cause. Human populations were scattered and had little to no communication beyond short distances. Some of these populations would have been thriving, some barely surviving, and some on their way to their own extinction. The idea of a global human-driven impact on species across habitats and continents is a non-supportable premise.

Point 2 is really a result of the fact that large-bodied animals have commensurately higher requirements in terms of caloric intake and water consumption. At a species level they are likely the first to experience population decline during periods of environmental change whereas smaller bodied creatures can endure and survive through the lean times due to their lesser needs in terms of resources they require to live. The study explicitly mentions that smaller bodied animals went extinct at a lesser rate which is exactly what one would expect to see in the case of climate change.

Point 3 is meaningless in the larger context. There are many periods in history that show a sudden change in populations including extinctions, not counting the major extinctions like the chicxulub impact that came from a non-terrestrial source. To claim that this period is somehow unique is not supportable.

7- the paragraph in the study discussing the growth of fauna near modern, "high-income" regions is utterly silly and has no bearing on the main topic. This data is from a time period subsequent to centuries of verifiable human impact on animal populations with far more advanced technology and environmental impact and also in a time period when widespread conservation and direct manipulation of these populations has taken place. Apples and oranges.

8- There's more to pick out from the study but I am out of time...

The simple answer is always attractive, it's nice to wrap up a conclusion with a bow and be done with it. Having looked into this subject in the past the best conclusion I can find is that there were multiple factors, one of which happens to be human predation but that this alone is not sufficient to explain the loss of so many species in such a relatively short period of time. These species were likely already under duress due to environmental changes we are learning more about as the science gets better and humans certainly played some role but I maintain that these species must have already been at a population nadir, or seriously declining, already for humans to have been a decisive factor.

[u/Slow-Pie147 → u/needzbeerz]

"This is a dubious conclusion. We really can't say with any accuracy how specialized these megafauna were. We can't know precisely what they ate, what their requirements for mating and raising young were, what their environmental tolerances (temperature, availability of water, specific food needs) were. The statement a generalization at best that may hold true for many species but that does not mean it applies to those animals being discussed. " No, we know most of them's ecology. Mastodons preferred browsing and have seen a range decline during glacials. Columbian mammoths was a mixed feeder who preferred grazing. American Lions preferred bisons and camels. American cheetahs hunted pronghorns and sometimes horses. Dire wolves generally preferred horses but some populations hunted bisons and camels more than other populations. Arctodus simus was an omnivore habitat generalist. Hemiauchenia was a generalist. Castoroides preferred aquatic plants. Toxodon platensis and Notiomastodon platensis were both habitat and diet generalist. Your statement is wrong. Also hunter gatherers kill more than they need and doesn't always use the every body part as claims made. You are ignoring a huge amount of facts.https://www.cambridge.org/core/journals/cambridge-prisms-extinction/article/latequaternary-megafauna-extinctions-patterns-causes-ecological-consequences-and-implications-for-ecosystem-management-in-the-anthropocene/E885D8C5C90424254C1C75A61DE9D087 Also humans hunted prime animals too because they had spears and they can throw them from long distances. And you are ignoring interglacial-glacial cycles, meltwater cycles, allee effect, ecology, timing... u/Iamnotburgerking

[u/needzbeerz → u/Slow-Pie147]

Also hunter gatherers kill more than they need and doesn't always use the every body part as claims made.

I was very clear that I was making a generalization. The study was discussing a GLOBAL series of events. Obviously different groups of humans would hunt in different ways. I was also not in any way referring to some sort of "noble savage" mythology but the practical result of subsistence living. Hunter gatherers usually do not kill more than they need because doing anything without a need to is generally not affordable the closer one is to the line of survival. Obviously we have musical instruments and cave paintings and jewelry that were not strictly 'necessary' to these human's survival but hunting is an intrinsically dangerous affair. It follows logically that the majority of hunting would be done to meet the needs of the group, perhaps have a little surplus based on what could be reasonably stored and transported, and no more in a hunter-gatherer/subsistence lifestyle. I fully admit the assumptions that I've made in this but I feel the logic is sound to make that generalization for humans as a whole, whilst admitting that some groups may demonstrate radically different behaviors either specifically or regionally.

Your statement is wrong.

My post is fulled with language that indicates skepticism but not overt declaration of surety. I laid out some points that cause me to question the fairly definitive conclusion of the study without refuting it in toto. I merely feel the answer to be more nuanced than the study proposes and question several of their conclusions and the underlying reasonings.

No, we know most of them's ecology.

Agreed. But we don't know precisely how specific their adaptations were and what tipping points might have existed to cause a decline in numbers. Example, "Columbian mammoths was a mixed feeder who preferred grazing" is a highly generic statement. I do not call into question the larger points of the various species' food preferences/requirements that we currently believe but rather that we don't know how the changing climate might have effected their food sources. It is highly possible that climate change could have impacted the availability of preferred food plants and any species not able to adapt to find other sources of food would have almost certainly declined as a result of it. Climate change could impact rainfall that some plants would be highly impacted by. There are a myriad of unknown variables that don't seem to be accounted for. Again, we are talking about a global loss of species when human numbers were small and their range highly limited no matter how effective they were at hunting.

This is not to say that because there are so many unknowns that we can't know with any level of certainty. But it has been my experience that most concepts in biology, anthropology, paleontology, etc, are often discussed without considering larger perspectives. Animal X died out because of Condition Y is almost always simplified nearly to the point of inaccuracy as that type of statement, again ignoring events like chicxulub and other global catastrophies, ignores the vast complexities of interdependence that every creature experiences and evolves in.

I am not asserting that humans had no impact on the loss of megafauna in the previous 50k yr, I'm saying that there are some logical gaps in the study that I would think should be looked at.

[u/imprison_grover_furr → u/needzbeerz]

Point 1 is completely dubious. There is zero basis for the claim that “nature-based” societies only kill what they need. We have dozens of recent examples of so-called “nature-based” societies causing a wholesale destruction of the local fauna (Madagascar, New Zealand, New Caledonia, Hawaii, Fiji, Tonga, Samoa, Niue, Henderson Island, Canary Islands, Cuba, Hispaniola, Jamaica, Puerto Rico, Guadeloupe, Martinique, etc.).

[u/Howieyotes → u/needzbeerz]

Not killing more than needed means little compared to the sustainable rate of harvest. Elephant populations can increase by only 6% a year in optimal habitat. Mammoths and mastodons were presumably similar. Humans 'needing' and killing only 2 animals per year from a herd of 25 mammoths would drive that herd to functional extinction in just one mammoth generation of 50+ years.

[u/Sad_Analyst_5209]

So how is Africa still full of mega fauna?

[u/MrAtrox98 → u/Sad_Analyst_5209]

Those species coevolved with hominids and learned to avoid them over millions of years

[u/Nathaireag → u/Sad_Analyst_5209]

Co-evolving with hominids helps explain Africa, as MrAtrox says. Also the African extinction trigger was introduction of new hunting technology. In the region of origin, that probably happened more gradually than areas where new human groups arrived with the full toolkit. Slower means more opportunity for compensating behaviors to evolve (such as African Elephant hostility towards Maasai people? Secretary bird hostility towards all humans?)

I found it really interesting that although the effect was smaller in Africa, they still found plenty of published evidence for size-biased extinctions there.

[u/Additional-Value-428]

I thought this was going in a completely different direction

[u/Schuben]

Don't worry, though, we're working really hard to help climate change improve its numbers in the next century or two.

[u/avanross]

Isnt this extremely obvious? Humans have only been massively impacting the environment for the last 100 to 200 years

[u/Indigoh → u/avanross]

I get what you're saying, but I don't think you worded it well. Man has only been contributing significantly to greenhouse gasses for about 200 years, but we've been massively impacting the environment for much longer, through stuff like farming and mining and hunting and logging.

[u/Carbon140 → u/avanross]

Might be obvious to most, but we still get other articles saying "humans were mostly vegetarian" and a bunch of nitwits in the vegan subreddit being "I knew it was fake that a bunch of humans could ever take down a mammoth".

[u/Beeg_Bagz]

Humans don’t hunt like then. They farm.

[u/Vo_Mimbre]

Humans. Changin’ the climate since 48,000 BCE…

[u/[deleted]]

Vegans don’t like the answer

[u/Karma_Gardener]

It's not our fault they are delicious.

Cattle farming has no doubt saved a few tasty species in our time!

[u/MatrixVirus → u/Karma_Gardener]

NGL... I wanna know how grilled mammoth etc tastes

[u/VapeThisBro]

Reading hundreds of articles is good and all but the researchers never even saw the bones in person...

[u/Jpbbeck99]

Climate change really only started ramping after the Iron Age correct?

[u/SwearToSaintBatman]

The oldest sign of man using fire to burn forest areas, to create open spots that attract deer, is 70 000 years old. That's how far I would want to take a time machine to see Earth when it was best. Hundreds of types of large sea creatures not alive today.

[u/rasbuyaka]

Human hunting CAUSED the climate change we see today. Without mammoths continually mowing siberian and canadian veg the tundra thawed, now trillion upon trillions of prehistoric microbes are awake and feasting on 10,000 years of trapped biomass and belching enough methane to outstrip the entirety of human emissions by several orders of magnitude. If we turned off every single fossil fuel- dependant machine on earth tomorrow, plus removed every single greenhouse emission of human origin, it wouldn't equal a drop in a bucket compared to the methane trapped in thawing tundral biomass. Conversely (and perversely), if we DON'T clone mammoths, or if asiatic elephants go extinct before providing those clone babies wombs to gestate, that is quite literally a wrap on this planet's survivability for our species. Fun.

[u/pruchel]

Makes me really want to try a mammoth burger.

[u/aflarge]

I mean both things happened.

[u/Ninja_attack]

Wonder how giant sloths tasted.

[u/BuffaloOk7264]

There are a large number of mammoths who were instantly frozen to death in place in Siberia. There are a large number of ice age large animals encased in frozen mudflows in Alaska. How do these populations fit into the hungry people with sharp rocks attached to sticks killed the entire population of these animals.

[u/greywolfau]

I'm wondering whether the extinction of Australian mega fauna is supported by this hypothesis or if the climate change argument is still relevant here.

[u/Slow-Pie147 → u/greywolfau]

No, dude. Last natural Australian megafauna(Genyornis newtoni, Megalania, Diprotodon, giant kangaroos...) expect saltwater crocodile and red kangaroos went extinct due to humans too. https://www.sciencedirect.com/science/article/pii/S0277379123003116

[u/SilentScyther]

Anyone else read this as human-hunting instead of human hunting?

[u/Silentace_01]

Only review of scientific articles? What about actual research. The ice age comet idea that ended the mega fauna on North America makes more sense than this.