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What Happened to Ancient Megafauna?

nautil.us

51–60 of 103 posts

Re: What Happened to Ancient Megafauna?

#51

> Defined as large-bodied terrestrial mammals with a mean adult body mass of 2,200 pounds or more, today’s remaining megaherbivores comprise the likes of elephants, rhinoceroses, giraffes, and hippopotamuses. Was there difference in hunter-gatherers in europe/asia/americas compared to africa? Why hadn't the ancient elephants, giraffes, etc been hunted to extinction? > I think work over the past few decades has rather…

> I have a hard time believing that hunter gathers in tiny tribes traveling on foot with primitive weapons could have hunted and wiped out entire species of large animals from continents. I wish they would give more specifics.

This made me recall having read something related to it in the book Sapiens [1]. Indeed, I went looking and quoting from chapter 4

> All the settlers of Australia had at their disposal was Stone Age technology. How could they cause an ecological disaster? There are three explanations that mesh quite nicely.

> Large animals – the primary victims of the Australian extinction – breed slowly. Pregnancy is long, offspring per pregnancy are few, and there are long breaks between pregnancies. Consequently, if humans cut down even one diprotodon every few months, it would be enough to cause diprotodon deaths to outnumber births. Within a few thousand years the last, lonesome diprotodon would pass away, and with her the entire species. [...]

> The second explanation is that by the time Sapiens reached Australia, they had already mastered fire agriculture. Faced with an alien and threatening environment, they deliberately burned vast areas of impassable thickets and dense forests to create open grasslands, which attracted more easily hunted game, and were better suited to their needs. They thereby completely changed the ecology of large parts of Australia within a few short millennia. [...]

> A third explanation agrees that hunting and fire agriculture played a significant role in the extinction, but emphasises that we can’t completely ignore the role of climate. The climate changes that beset Australia about 45,000 years ago destabilised the ecosystem and made it particularly vulnerable. [...]

So the extinction was on a very different timescale from your buffalo example, but an extintion nonetheless. In the ellipses the book briefly points to some evidence to support these theories.

[1]: https://en.wikipedia.org/wiki/Sapiens:_A_Brief_History_of_Hu...

Re: What Happened to Ancient Megafauna?

#52
post #33

Earlier quoted context omitted.

Right, we're a native species to Africa, so its whole ecosystem evolved with us. I think of this when I hear about "poachers" killing animals in African nature reserves. How often is that hunter gatherers who been there for thousands of years, and whose hunting is/was really part of the ecosystem?

Hunter gatherers who are killing Rhinos only to sell their grounded horns to some idiots in China/etc.?

That's not the only hunting banned in national parks!

Re: What Happened to Ancient Megafauna?

#53

> Defined as large-bodied terrestrial mammals with a mean adult body mass of 2,200 pounds or more, today’s remaining megaherbivores comprise the likes of elephants, rhinoceroses, giraffes, and hippopotamuses. Was there difference in hunter-gatherers in europe/asia/americas compared to africa? Why hadn't the ancient elephants, giraffes, etc been hunted to extinction? > I think work over the past few decades has rather…

> Was there difference in hunter-gatherers in europe/asia/americas compared to africa? Why hadn't the ancient elephants, giraffes, etc been hunted to extinction?

Elephants and rhinos do survive in Asia.

Re: What Happened to Ancient Megafauna?

#54
post #26

One idea I had a while back is this: with all our modern technology in stem cell research, gene modification and cloning, shouldn't it be possible to recreate actual living clones from prehistoric dinosaur DNA? I mean, sure, these giant wild animals could potentially become dangerous, but how about we confine them to a remote island or so?!

See https://en.wikipedia.org/wiki/De-extinction , https://en.wikipedia.org/wiki/Revival_of_the_woolly_mammoth and https://en.wikipedia.org/wiki/Pyrenean_ibex#Cloning_project

A huge issue with "Jurassic Park" style cloning is that old DNA degrades very quickly

Re: What Happened to Ancient Megafauna?

#55
post #7

The linked nautil.us article is a one sided poor summary of what is still an ongoing debate with strong beliefs on either side. Two people are quoted: * Jens-Christian Svenning, director of the Danish National Research Foundation’s Center for Ecological Dynamics in a Novel Biosphere at Aarhus University. He’s also the lead author on a recent paper published in Cambridge Prisms: Extinction that argues it was not clima…

Here's my question: if humans caused megafauna extinction, why did this not happen in Africa? That's where many of the megafauna continue to live. But humans came from Africa.

Re: What Happened to Ancient Megafauna?

#56
post #7

The linked nautil.us article is a one sided poor summary of what is still an ongoing debate with strong beliefs on either side. Two people are quoted: * Jens-Christian Svenning, director of the Danish National Research Foundation’s Center for Ecological Dynamics in a Novel Biosphere at Aarhus University. He’s also the lead author on a recent paper published in Cambridge Prisms: Extinction that argues it was not clima…

Here's my question: if humans caused megafauna extinction, why did this not happen in Africa? That's where many of the megafauna continue to live. But humans came from Africa.

The theory is that African megafauna evolved alongside humans, learned to fear them, and developed strategies to avoid them. Whereas other megafauna didn't, so when humans left Africa, they were defenseless.

Re: What Happened to Ancient Megafauna?

#57
post #7

The linked nautil.us article is a one sided poor summary of what is still an ongoing debate with strong beliefs on either side. Two people are quoted: * Jens-Christian Svenning, director of the Danish National Research Foundation’s Center for Ecological Dynamics in a Novel Biosphere at Aarhus University. He’s also the lead author on a recent paper published in Cambridge Prisms: Extinction that argues it was not clima…

Here's my question: if humans caused megafauna extinction, why did this not happen in Africa? That's where many of the megafauna continue to live. But humans came from Africa.

Somewhat speculative of course—the extant megafauna you’re referring to are somewhat endangered and but also don’t represent great sources of usable materials such as meat or skins. Additionally, many are quite dangerous — rhinos, hippos, and elephants to be specific.

Re: What Happened to Ancient Megafauna?

#58
post #7

The linked nautil.us article is a one sided poor summary of what is still an ongoing debate with strong beliefs on either side. Two people are quoted: * Jens-Christian Svenning, director of the Danish National Research Foundation’s Center for Ecological Dynamics in a Novel Biosphere at Aarhus University. He’s also the lead author on a recent paper published in Cambridge Prisms: Extinction that argues it was not clima…

Here's my question: if humans caused megafauna extinction, why did this not happen in Africa? That's where many of the megafauna continue to live. But humans came from Africa.

[deleted]

Re: What Happened to Ancient Megafauna?

#59
It's always seemed patently obvious to me that humans were the primary cause of megafauna extinctions. First and foremost because the timing of extinctions aligns so closely with the arrival of humans in a given region, but also because the climate has changed dramatically over the past few million years or so, with cooler or warmer periods happening frequently over geological timespans, yet we don't see similar extinction events happening around climatic cycles / events other than those that happen to align with the arrival of humans in a given region. The Mammoths of North America for example survived numerous cycles of warming and cooling, some far more drastic than the most recent ice age and subsequent warming period, so why was it only the most recent one that caused their extinction? We already have control data for the effect climate had on megafauna populations, the only variable left is us humans.

Re: What Happened to Ancient Megafauna?

#60
post #7

The linked nautil.us article is a one sided poor summary of what is still an ongoing debate with strong beliefs on either side. Two people are quoted: * Jens-Christian Svenning, director of the Danish National Research Foundation’s Center for Ecological Dynamics in a Novel Biosphere at Aarhus University. He’s also the lead author on a recent paper published in Cambridge Prisms: Extinction that argues it was not clima…

Here's my question: if humans caused megafauna extinction, why did this not happen in Africa? That's where many of the megafauna continue to live. But humans came from Africa.

[deleted]
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