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What Killed the Great Beasts of North America?
sciencehabit writes "Until about 11,000 years ago, mammoths, giant beavers, and other massive mammals roamed North America. Many researchers have blamed their demise on incoming Paleoindians, the first Americans, who allegedly hunted them to extinction. But a new study points to climate and environmental changes instead. The findings could have implications for conservation strategies, including controversial proposals for 'rewilding' lions and elephants into North America."
My bad. Sabertooth tiger and Mammoth just tasted so good.
The cow says "Moo." The dog says "Woof." The Timothy says "Thanks, valued customer. We appreciate your input."
I see great hambeasts of North America roaming about everytime I go to Walmart. Largest in the world.
We have no shortage of large, XL, XXL, XXXL, or XXXXL wildlife.
Yeah, that's real shocker in the story. Someone wants to introduce elephants and lions to what is now cattle ranch territory? There has already been a crazy amount of push back when reintroducing wolfs into different areas.
Something tells me elephants won't pay attention to barbed wire fences.
Plus, aren't we already having a difficult time keeping mountain lions alive?
Well.. maybe. Or Maybe not. But Definitely not sort of.
Oh, the orbit matters... but the orbit is EXTREMELY predictable even its wobble and orientation. It might, perhaps tip the scale during the (likely ongoing) pleistocene (Where 90% of our time is spent in ice age with 10% warm snaps that should have already ended by now, contrary to spiking upwards instead) but ebbs on a timeline that should have had the pleistocene happening essentially since beginning of observable time (which it has not.) So, it's a factor, but not a decisive one. Continental arrangements and landmasses propensity for temperature extremity vs. oceanic propensity for temperature moderation and long-distance transport matter far more (even than tilt, given measuring the southern hemisphere vs. northern.) And yet, in spite of the fact that the continents and oceanic currents are still in the same messy tangle they have been for the entirety of the multi-million year pleistocene, these beasts didn't go extinct during an of the previous warm-snaps... just the one we arrived in... and now that we should be quickly descending into ice age, instead we're headed the other way. This article is of interest, but it is not argument against anthropogenic extinctions or climate change.
Large mammals managed to survive for a long, long time before people came to Americas and then, shortly after people came, they were killed off by "climate and environmental changes"? Sounds a bit fishy to me!
This is where the Samurai crab comes from...
A Pirate and a Puritan look the same on a balance sheet.
Seriously, nobody is actually proposing this, are they?
Artificially tampering with Mother Nature by bringing back extinct species into modern environs is probably even worse in the end than (maybe) helping to drive them into extinction to begin with. Sometimes, it's best to just let it go. Much as I would love to see the beautiful Carolina Parakeet back in the wild (and maybe even own one as a pet), I know it's best not to go tampering around where my good intentions could lead to very unexpected (and perhaps very unpleasant) results.
The cow says "Moo." The dog says "Woof." The Timothy says "Thanks, valued customer. We appreciate your input."
When will someone kill two birds with one stone. . .and make Soylent Bieber ???
Waiting for someone with a four digit UID to reply "you must be new here"
I'm on it!
You must be new here.
There are very few cases where introducing a non-native species into the wild has turned out to be a good thing. There are hundreds of examples of things going wrong. Just look up invasive species. Our track record is not good.
People killed them. Either by direct means or global warming.
Or, I blame God.
There were never enough Paleoindians, or even Pre-Columbian indians in north america to have killed all of these animals.
The indigenous populations of the Americas (north and south) was somewhere well under 112 million prior 1492.
(Yup the Columbus gets the blame for native population collapse, even though far earlier arrivals could certainly have been the vector for deadly diseases).
I never believed the hunted to extinction nonsense. (Not that Native Americans were very good stewards of the land, they had been known to stampede entire herds of buffalo over cliffs just for their tongues, and a few hides, leaving the vast majority to rot.) But their population density simply was never great enough to exhaust the resources.
I don't find the idea that a steadily improving (more benign) climate over the time of these species demise seems likely either. With the retreat of the ice age glaciation opening more and more land the pressure on these species would have been less and less as time went on. We are always quick to blame man kind, (but apparently only western European man-kind) for every tragedy befalling the environment, (or the indians), without considering that disease could have been just as likely.
Sig Battery depleted. Reverting to safe mode.
You'd have to be crazy.....
Seriously...the earth is hotter than it's ever been before...so I was told, by Mr. Al Gore.
Great, that's just what we need. Africanized Asian elephants. Have you not heard what happened when we Africanized honeybees? We'll have swarms of tempermental pachyderms stampeding through every village in the Great Plains before mid-century.
The Quirkz Handbook of Self-Improvement for People Who Are Already Pretty Okay
I very stupidly just Googled "giant beaver" at work.
Seems likely that this is the article. If so, I've only read the abstract so far, but TFS seems to misrepresent the authors' conclusion.
TFS claims:
whereas the abstract says:
In other words, the authors are not saying humans were not involved in the extinctions. They are saying human predation cannot be the *sole* cause.
[Sir Garlon] is the marvellest knight that is now living, for he destroyeth many good knights, for he goeth invisible.
My personal theory is that the pleistocene has been so cold because of the historically (4 billion years) high oxygen levels and the significant amount of historical carbon that has been sequestered underground.
Humans are changing that, we're sucking all the sequestered carbon out and putting it into the atmosphere where it hasn't been since the dinosaurs. Before all the science deniers reply, this is scary because humanity was born in the ice ages of the Pleistocene we've never experienced a planet as warm as the dinosaurs where there weren't any ice caps and it was 100 degrees in the northern reaches of Canada (yes I know the continents were in different places so Canada was at a lower latitude).
Humans will survive a warmer earth I have no doubt, but the potential for massive disruption to the food supply is there and if that happens there's going to be some really ugly war that humanity might not survive. The reason to be scared of global warming is because of those changing fertile zones, humanity goes batshit crazy when starvation is eminent.
Well, Clovis, don't keep us hanging - what did happen 11,000 years ago?
Have you read my blog lately?
That bit about continents *is* a standard theory... but it has nothing on 11k years ago. Same thing goes for the orbit. So no, it isn't the orbit, and it isn't the landmasses.
Let's see... you have the North American Clovis Point people going extinct at the same time. So it isn't *who* killed them either. If the Clovis people had killed them off, you wouldn't have had them going extinct.
Also, at the same time, you have wildfires throughout North America. That soot contains microdiamonds.
You also have mammoths in Siberia at that time, flash frozen (Alaska Science Forum November 1, 1976. Mystery of the Mammoth and the Buttercups Article #122 by J. Holland).
You also have great areas in Alaska of jumbled up, blasted fauna caracases, many of them torn apart.
Now, all told, I'm going to posit -- and I doubt I'm the first to do so -- that an asteroid hit a glacier up against the south side of a mountain in Northern Alaska. The first thing it did, was melt/throw the ice of the glacier in a great parabolic trajectory. The water of the glacier went into near space, froze to extremely low temperatures, and came down. But meanwhile, the asteroid impacted the south side of the mountain, and vaporized, causing a fireball to project back into North America.
Thus the soot, thus the extinctions (animal and Clovis culture), thus the flash-frozen mammoth, thus the tectites, thus the great boneyards.
And no, for those creationists here, I extremely doubt that ANY of this had to do with Noah's flood. Noah's flood dates to about 5000 ya, and seems to match the Madagascar chevrons and 8' of river mud, pretty well. This is something different.
Correct Horse Battery Staple: 72 bits of entropy. Enter "Correct H" into google. When it generates the phrase, that's
"We did, we did."
How about you actually study some real Paleoclimatology instead of pulling neo-liberal statements out of your ass?
The truth is, the earth, as a whole, is currently at about the lowest average temperature that can be inferred from the all sources of ancient data. Normally, we should be about 2-3 C higher, globally, given the historical record.
"Global Warming" is just a return to trend and should be expected whether humans are walking around or not.
"Unheard of means only it's undreamed of yet,
Impossible means not yet done." ~~ Julia Ecklar
I know it's best not to go tampering around where my good intentions could lead to very unexpected (and perhaps very unpleasant) results.
I see your point with one caveat. You don't actually "know" what you claim to know. Good intentions can lead to very unpleasant results or they could lead to very wonderful results. One way to find out is by actually doing it and seeing what happens.
Good points, Plate tectonics provides a better explanation for Cenozoic Era paleoclimates than just the carbon cycle. The Eocene-Oligocene change has to do with Antarctica drifting over the south pole and icing up. This disrupted ocean circulation and was caused by the breakup of Gondwanaland and the beginning of the circumpolar currents in the Southern Hemisphere. The climate cooled even more in the Miocene and Pliocene because the northern continents surrounded the Arctic and restricted warming sea water from the North Pole. The orbital fluctuations were made critical by the ocean circulation, not the carbon cycle. The carbon cycle is a response to ocean productivity, most carbon fuels are marine in origin. That was very much affected by the land bridges connecting the Americas and Asia, even though the Atlantic opened up. Diverting the Gulf Stream into North Europe, rather than it going from Africa across the Gulf of Mexico and into the Eastern Pacific as it did in Eocene time, would cause greater snow in Northern Europe and Canada that would not melt from season to season and lead to continental glaciation.
As for the cause of the Mass Extinction, the numbers of human in the Americas, only a few thousands, a not enough to explain the collapse of the megafauna, even if people were successful preditors, It is more likely that climate instability and the collapse of food stocks for specialized animals was the real cause. The animals could not adapt, the changes were too fast, happening in decades rather than millenia, and the spieces went extinct.
For our continued existence as megafauna, defined as needing expensive food to survive, it is climate instability that poses the greater risk than ice ages or not. We could have clearly survived in an Eocene climate and we did fine in a Pleistocene one, but to have Eocene in the next 30 years and Pleistocene in the following 30 would be very bad for us.