Guest essay by Eric Worrall
Our old friend Chris Turney, whose ship of fools got stuck in the ice while he was attempting to study global warming in the Antarctic, and replicate Mawson’s expedition, has published a new study which claims that Mammoths were killed by climate change.
According to Turney’s abstract;
The mechanisms of Late Pleistocene megafauna extinctions remain fiercely contested, with human impact or climate change cited as principal drivers. Here, we compare ancient DNA and radiocarbon data from 31 detailed time series of regional megafaunal extinctions/replacements over the past 56,000 years with standard and new combined records of Northern Hemisphere climate in the Late Pleistocene. Unexpectedly, rapid climate changes associated with interstadial warming events are strongly associated with the regional replacement/extinction of major genetic clades or species of megafauna. The presence of many cryptic biotic transitions prior to the Pleistocene/Holocene boundary revealed by ancient DNA confirms the importance of climate change in megafaunal population extinctions and suggests that metapopulation structures necessary to survive such repeated and rapid climatic shifts were susceptible to human impacts.
The full study is unfortunately paywalled, but I think we get the idea.
Mammoths survived from the Pliocene epoch, around five million years ago, to around 4500 years ago – so they survived until the end of the Holocene Optimum, the peak warm period of our current interglacial, which preceded our cooler modern climate.
However, the Mammoths also survived the Eemian Interglacial, a much warmer period than today, which occurred between 130,000 and 115,000 years ago. The Mammoths survived the mid Pliocene, 3 million years ago, when temperatures were 2-3c higher than today, and sea levels were 25m higher.
So it seems likely Mammoths would have survived the comparatively feeble warmth of our Holocene, if it weren’t for humans.
History books I used to study, suggest humans built cunning traps for the megafauna they hunted. Who hasn’t seen dramatic pictures of primitive humans holding spears, surrounding some rearing colossus.
But this isn’t the full story. Primitive humans made extensive use of fire. Fire had multiple benefits; Grasslands are highly productive, in terms of food animals, more so than forests, where many of the interesting animals live up the tops of the trees, out of reach. Deliberately burning the forests on a regular basis created more grasslands. And frankly, why bother chasing big animals, risking injury and death, if you can simply set fire to the entire region, then wander over afterwards and brush the charcoal off the pre-cooked meat? Kind of a primitive version of fast food.
Turney’s abstract grudgingly acknowledges the impact of humans on megafauna. But I suspect the human influence was probably far more important than the climate influence. Otherwise, mammoths would have survived the comparatively feeble warmth of the Holocene, just as they survived much warmer past interglacials, over their long existence.
A few years ago I read a book (1492, Bones?) that claimed there were far more people in North and South America than we would care to admit (prior to the arrival of the Europeans). So why wouldn’t they have had a much greater negative impact on the environment?
There were, until comets wiped them out. See http://wattsupwiththat.com/2015/07/24/ship-of-fools-leader-humans-didnt-kill-the-mammoths/#comment-1992666
Burning forests and grasslands huh? So that’s where the CO2 came from (sarc)
AnOther ***SHIP OF FOOLS!
12 May: AnOther Mag: Art at the Ends of the Earth
Antarctica enters the whirlwind of Venice with Concordia, a thoughtful installation considering exploration and morality
(Concordia is at the Antarctic Pavilion, Venice (The Venice Biennale) until November 22.)
The celebrated artist-curator pairing of Alexander Ponomarev and Nadim Samman, jointly named in the top 100 global thinkers by Foreign Policy Magazine, is now showing at the duo’s Antarctic Pavilion in Venice. “We appointed ourselves the cultural ministry of Antarctica,” says Samman. “We are interested in the concept of transnational community. Antarctica is the closest thing to an existing political utopia that we have on this planet. Antarctica is liberation.”…
Ponomarev and Samman view the continental ice shelf of the Antarctic as a blank canvas, freed from national, economic, military interests under the 1959 Antarctic Treaty, and without a native population beyond a few penguins and a smattering of international scientists. Here, the pair propose a floating biennale.
***”A SHIP OF FOOLS or a floating embassy,” says Samman, “[that] will explore the potential of Antarctica for world culture.” Research ships carrying artists out voyaging over the southern oceans, making art away from the intervening scrum of collectors, gallerists and media, in search perhaps of a promised land, of purity, of a salvation from ourselves out over the ends of the world. Behold, the white whale, that great cold icy mass, that snowy hill. There she blows…
http://www.anothermag.com/art-photography/7406/art-at-the-ends-of-the-earth
It is so obvious that human hunting was responsible for the large-animal extinctions of the past 20,000 years that scientists denying this deserve a “denier” label all of their own.
What was the cause of these rapid fluctuations in climate?
Just how big and how rapid were they?
What were the CO2 levels during this climate change?
What was the impact on the human population during this sudden climate change?
What was the impact on whole of the biosphere?
The Bison certainly saw a “tipping point” but it would appear things just got better for the rest of us.
The other issue here is why elephants still survive in Africa, which is often cited against the human influence for mammoth extinction. The answer is quite surprising.
You have to go to Africa for a while to realise what the answer is. Elephants there are protected from overhunting by humans, until very recently when guns arrived on the scene, by 2 major factors, the presence of many other dangerous carnivores which render hunting them impractical (you can be taken out by a lion or a leopard whilst hunting), and the presence of many other easier hunting alternatives (many kinds of plant eaters which are far easier to kill without a gun). Both these factors are absent when one leaves Africa and goes into colder regions.
In fact the presence of so many dangerous predators in Africa is so acute, that this is probably why humans evolved further north-in either Ethiopia which is much drier and has less predators- and possibly further north still around north Africa region-early homo sapiens was distinctly thin and tall suggesting most evolution occurred within warm dry climates where there are less predators to contend with.
C’mon, guys. It’s simple. Cave men start fires. Fires produce CO2. CO2 causes Climate Change. Climate Change wipes out mammoths. Clear?
Always amazes me when i read that ” scientist ” knew what happened a few thousand years ago and and the same ” scientist ” are in the ” dark ” about current events .
Mammoths. So easy to kill, even a caveman can do it.
They were probably killed when the earth was struck by a giant icy comet 4,500 years ago. That is why they are found frozen with tropical vegetation still in their mouths and why we have so may specimens that are in great shape. They were frozen instantly and buried in ice. They weren’t killed by hunters and then eaten they are all still intact.
They find a lot of frozen stuff in Siberia. The woolly rhinoceros.http://archaeologynewsnetwork.blogspot.com/2012/12/prehistoric-rhino-reveals-secrets.html#.VbOjZLeFlNY A baby wooly rhinoceros. http://siberiantimes.com/home/born-in-siberia/b0009-meet-sasha-the-worlds-only-baby-woolly-rhino/ and wooly mammoths all over the place. http://www.timeout.jp/en/tokyo/event/9429/Yuka-Wooly-Mammoth-Show
What tropical vegetation?
Frozen Pleistocene megafauna stomachs contain steppe tundra vegetation.
http://www.cbc.ca/news/technology/woolly-mammoth-diet-mystery-solved-by-dna-analysis-1.2524015
This is exactly the type of drivel that falls out of digestive tracts of large, male bovines because there are no consequences in “the academy” for pure hogwash.
Having said that, I intend no disrespect to large male bovines.
We had mini-mammoths on our beaches. They enjoyed swimming.
http://phenomena.nationalgeographic.com/2015/06/01/the-making-of-californias-mini-mammoths/
How can the climate change hypothesis explain the disappearance of less hairy Columbian mammoths along with the cold-adapted woollys?
A warmer world would have been to their liking, extending their range.
Megafauna died off in Australia shortly after the arrival of people. A coincidence ? Perhaps climate change did it ? But as with elsewhere outside Africa the megafauna survived long periods of climate fluctuations but most didn’t survive people.
And it doesn’t have to be as dramatic as imagined pictures of humans killing adult mammoths….herding them into traps or over cliffs.
Just chase down the young ones. Large animals are generally slow breeders. If you kill the smaller, more vulnerable juveniles you will drive animals to extinction more effectively and much more easily than trying to kill the adults.
http://www.iceagenow.com/Of_Magnetic_Reversals_and_Ice.htm
I think it has to do with magnetic reversals.
LaBrea Tarpits. I have often wondered when someone would find the remains of at least a solitary stupid or clumsy humanoid that fell into one of those pits perhaps with clothes and weapons / gear sort of like the other beasts of those earlier times. It might prove interesting. Perhaps was pushed by friends ?