The melting of the large continental ice shields was not a steady warming event. It was interrupted by sudden and severe cooling periods
What Killed the Mammoths—Heatstroke or Frostbite?
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A new study on the woolly mammoth has linked their demise, approximately 10,000 years ago, to – what else could it be but “climate change.“ The progressive news media are all over it.
Headline at www.news.com.au: “Extinction events linked to prehuman global warming.” The reportage says “Lead author University of Adelaide Prof. Alan Cooper found extinction events “staggered through time” across the northern hemisphere coincided with short, rapid warming events,” etc.
Headline in the National Geographic: “Abruptly Warming Climate Triggered Megabeast Revolutions.”
Headline in the Democratic Underground, LLC: “Mammoths killed by abrupt climate change.” In the text “Published today in Science, the researchers say by contrast, extreme cold periods, such as the last glacial maximum, do not appear to correspond with these extinctions.”
Headline by Micah Dacolo at the Dispatch Times: “Climate change brought the extinction of woolly mammoths, and more could follow the trend” and further down “The study gave an highlight of the fact that climate change has been a great threat to animals and global warming, which is the one of this era could have a major repercussion.”
The paper in Science that the report refers to has the title “Abrupt warming events drove Late Pleistocene Holarctic megafaunal turnover.” Its abstract is no less illuminating than its title and concludes with “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.”
Unmistakably, the mammoths must have succumbed to heatstroke and perhaps not only the mammoths. Imagine, as the scientists claim “Temperatures increased 4C to 16C over just a few decades and “lasted for hundreds to thousands of years”, causing “dramatic shifts in global rainfall and vegetation patterns.”
You don’t want to get that either. Of course, frostbite is just killing your extremities, toes, fingers, nose or ears. However it often precedes severe undercooling of the whole body with subsequent death. When the body gets too cool, it shuts off the blood circulation to the limbs and skin and tries to preserve the most important functions of the sensitive vital organs. That increases the blood pressure in the body interior so much that people may actually think that they are hot while their skin and extremities are freezing.
It is not uncommon for people with severe hypothermia (undercooling) to completely undress in order to relieve their perceived overheating. From a “technical perspective” you might say that their body temperature sensors have gone mad. On the inside these persons feel like overheating but in fact they are losing vital body heat on the outside. Unfortunately, without timely relief (prevention of heat loss and outside heat) it portends the imminent end of their lives.
Back to the Woollies though and the question as to what did them in:
It pays to read the brief article by Dacolo to the very end. The very last sentence of that exposé changes the whole message you may have taken from the front part of the story by 180 degrees. At the end it says:
“Though scientists were able to figure out cold weather was the reason for extinction, advancements in DNA sourcing from fossils and carbon dating helped them to strengthen the study.”
You’d better read that sentence twice. It states the woollies died out from COLD, not from heat!
Obviously, there are some substantial contradictions between the news stories as relayed by different sources. So, I contacted the corresponding authors with a simple question, namely “…was it warming or cooling that did the mammoths in?”
The reply I received from Dr. Cooper to my question said: “…it looks as though the Dispatch Times hasn’t read the paper or media release very closely!” Well, that media release by the University of Adelaide says “It became increasingly clear that rapid warming, not sudden cold snaps, was the cause of the extinctions during the last glacial maximum” but the mammoths died out much later than the last glacial maximum (approximately 20,000 years ago). Clearly neither Dr. Cooper’s email reply to me nor the university’s media release really answered my question.
Interestingly, other findings by Dr. Cooper appear to contradict his new work as well. For example, in 2012, he and coworkers wrote in PLOS ONE “Epigenetic modifications have the potential to create phenotypic diversity in response to environmental cues, and unlike genetic changes, can be induced in multiple individuals in a population simultaneously. This would allow rapid adaptation to a changed environment, and in the face of intense selective pressure (as may be experienced during climatic change), pervasion of a phenotype throughout a population without any genetic change.”
The Coup de Grace?
If it is that simple to adapt to climatic change, why did the entire population of perhaps hundreds of thousands of mammoths in the northern areas of North America, Europe and Asia all die in short order? The study’s co-author, Prof. Chris Turney from the University of New South Wales has the answer: “…the rise of humans applied the coup de grace to a population that was already under stress.” The few inhabitants of these vast areas, with the total population probably only a small fraction of the numbers of mammoths roaming the landscape are supposed to have hunted them to extinction. The mammoths must have just about lined up and stood idly by to get slaughtered with stone-age knives. Frankly I find that claim to be even more preposterous.
The melting of the large continental ice shields was not a steady warming event. It was interrupted by sudden and severe cooling periods. The animals that were following the retreat of the ice cover into new habitat were unable to escape the reversal of fortune. For example, the Younger Dryas period (lasting for approximately 1,500 years and ending some 11,000 years ago) saw a rapid return to glacial conditions in the higher latitudes of the Northern Hemisphere in sharp contrast to the warming of the preceding interstadial deglaciation. Such transitions occurred over a period of a decade or so but the onset may have even been faster (Wikipedia). That period is described in the university’s media report as “the sudden disappearance of mammoths.”
Whatever killed the mammoths, it wasn’t heatstroke and it wasn’t hunting. Of course, what really happened to the mammoths has long been known already. It has been described in vivid terms by Robert Felix in his book Not by Fire but by Ice. He also quotes from Adrian Lister and Paul Bahn’s 1994 book Mammoths: “Some estimates suggest that there are 10 million mammoths still lying in the Siberian deep freeze.” Then there are the countless bodies of reindeer, giant bison, giant elk, wolverines, cave lions, beavers, horses, and wolves that all have washed out along river banks from the permafrost areas of Siberia.
There are even claims that dogs and scavengers were feeding on such freshly exposed carcasses. Why are these carcasses decomposing now rather than 10,000 or 5,000 years ago when the animals died rapidly? Would such carcasses have been preserved the way they are if they had not been “frozen on the spot” but had died from “heatstroke?” So, what really did the mammoths in? I’m keen to hear your opinion about the cause of the Woollies’ demise.
“Climate change” is not unidirectional and can portend colder temperatures too—not only for the mammoths.