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The "humans wiped out the megafauna" tale is crumbling.

macdoc

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As is the arrival of humans in North America was not earlier than Clovis nonsense.

Giant sloths and mastodons coexisted with humans for millennia in Americas, new discoveries suggest​

prehistoric-hum-and-sloth-illustration-1-7153334-1734702919134.jpg

10,000 years co-existence....sort puts a hole in the rapacious humans idea,:rolleyes:
 
10,000 years co-existence....sort puts a hole in the rapacious humans idea,:rolleyes:
Does it, though? Human population in the Americas doubled every [insert unit of time] from the original settlement up until the arrival of the Columbian expedition and the conquistadors. At some point this population pressure would cause people to tax the native fauna much more than they did at first.
 
10,000 years tho ......:unsure: and why did some like the bison thrive while others died out. ( Giant beaver etc )
Certainly not denying humans as a factor but not the primary cause. We were were still hunter gatherers not railroad mobs with Sharps rifles.

In Australia megafauna were going extinct long before humans arrived even tho that arrival was 60k years ago.
I suspect climate/habitat changes and even predator prey relationship changes.
The speedy longhorns stayed around long after their top predator disappeared in North America. Don't think humans preferred some stringy ubercheetah meal so selectively weeded out the predator. :sneaky:
And the proghorn outlived two of their predators...lions and cheetahs...and maybe dire wolves too,.
The Pronghorn ‘antelope’ (Antilocapra) of western North America have long been enigmatic because they are the second-fastest modern land mammal with no natural predators that come close to matching their speed. With the discovery of the now-extinct North American cheetah, Miracinonyx, the hypothesis was put forward that the incredible speed of pronghorns was related to being the primary prey of the fleet-footed Miracinonyx. However, there has been no direct means to test that relationship. Here, utilizing organic-molecule-rich bones from Natural Trap Cave, it is possible to test the predator-prey relationship between Antilocapra and Miracinonyx through isotopic analysis of bone collagen. Offsets in carbon and nitrogen isotopes between predator and prey are used to establish or discount predator-prey relationships between common predators found in Natural Trap Cave including wolves (Canis), cheetah-like cats (Miracinonyx), and North American lions (Panthera) with prey species like horses (Equus and Haringtonhippus), pronghorns (Antilocapra), sheep (Ovis), and bison (Bison). Results provide support the hypothesis that Miracinonyx preyed upon Antilocapra, but not exclusively. Antilocapra was also important prey for lions and wolves. Wolves appear to have fed more often on horses than lions or cheetahs.
 
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The insanely aggressive, or distrusting, or hyper-nimble survived, while everything else was eaten.

(Not to mention reproductive strategy.)

Apparently it took about 10,000 years for humans to wipe out the mega fauna in Australia too.

It's surprising how long it takes to wipe out animals when you don't have guns...
 
It's not as if the humans suddenly arrived in huge numbers- the QE2 didn't pull up and thousands streamed ashore, immediately killing everything in sight... more likely only a single handful arrived at first...

Initial numbers of humans would have been tiny in numbers, and it would have taken time before their numbers grew to numbers large enough to make a large impact on megafauna numbers...

It actually makes sense to hunt megafauna like the beavers in the US or kangaroos and wombats here- a single kill gives you a LOT of meat where hunting their smaller cousins means you have to make a lot more kills to get the same amount of meat- its why going after something rat sized would be a poor choice (unless you are desperate lol)- lots of time and energy expended for not much gain...

Although hunting megafauna 'predators' doesn't make much sense (too risky lol) as their source of large prey animals drops in numbers, they also start having trouble maintaining their numbers as well- no easy large food source means their numbers have to decrease...

The fact that humans and megafauna coexisted for relatively short periods of time before their extinction doesn't invalidate the 'humans helped make megafauna extinct' hypothesis, at least for me...
 
The Moa was definitely wiped out by humans.

Before the arrival of humans, the moa's only predator was the massive Haast's eagle. New Zealand had been isolated for 80 million years and had few predators before human arrival, meaning that not only were its ecosystems extremely vulnerable to perturbation by outside species, but also the native species were ill-equipped to cope with human predators. Polynesians arrived sometime before 1300, and all moa genera were soon driven to extinction by hunting and, to a lesser extent, by habitat reduction due to forest clearance. By 1445, all moa had become extinct, along with Haast's eagle, which had relied on them for food. Recent research using carbon-14 dating of middens strongly suggests that the events leading to extinction took less than a hundred years, rather than a period of exploitation lasting several hundred years as previously hypothesised.
 
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