I have posted extensively on the Pleistocene Nonconformity and the targeted polar blast that appears to have triggered it. I will also soon be posting a short update on the conjecture itself.
One other important result is also obvious. African lions are hunters of men and the Africans have barely kept the modern lions at bay. These suckers were impossible to keep at bay. That explains the limited human involvement with Pleistocene fauna. Strong defensive strategies were mandatory and this surely meant maximum use of thorn thickets and travelling in well armed groups. The Clovis point becomes very necessary, not for bringing down game but to confront these carnivores.
The existence of these lions is in fact additional indirect confirmation of unusual nature of the Pleistocene Nonconformity itself. These predators were adapted for the climatic conditions and stayed within their northern niche. Had they had time to readapt to more southerly climes, they would certainly have shifted south and hunted elephants. Instead they hunted musk oxen, black bears, grizzlies and smaller mammoths at least.
For the record, we have determined the nature of the Pleistocene Nonconformity in a number of earlier posts as a crustal shift triggered by a targeted blast - impact close by the pole whose blast - shock wave shattered the Pleistocene world. Ample evidence of time, direction and location has emerged and been posted on. And yes, we deal with the obvious objections.
Lions were the most widespread carnivores in the late Pleistocene, ranging from southern Africa to the southern USA, but little is known about the evolutionary relationships among these Pleistocene populations or the dynamics that led to their extinction. Using ancient DNA techniques, we obtained mitochondrial sequences from 52 individuals sampled across the present and former range of lions. Phylogenetic analysis revealed three distinct clusters: (i) modern lions, Panthera leo; (ii) extinct Pleistocene cave lions, which formed a homogeneous population extending from Europe across Beringia (Siberia, Alaska and western Canada); and (iii) extinct American lions, which formed a separate population south of the Pleistocene ice sheets. The American lion appears to have become genetically isolated around 340 000 years ago, despite the apparent lack of significant barriers to gene flow with Beringian populations through much of the late Pleistocene. We found potential evidence of a severe population bottleneck in the cave lion during the previous interstadial, sometime after 48 000 years, adding to evidence from bison, mammoths, horses and brown bears that megafaunal populations underwent major genetic alterations throughout the last interstadial, potentially presaging the processes involved in the subsequent end-Pleistocene mass extinctions.
From Scientific American:
Mar 30, 2009 05:25 PM in Archaeology & Paleontology
Massive lions prowled North America not so long ago
By Katherine Harmon
Large lions roamed North America and Europe as recently as 13,000 years ago, according to a new study published in Molecular Ecology. "These ancient lions were like a super-sized version of today's lions, up to 25 percent bigger," study co-author Ross Barnett, a researcher at the Ancient Biomolecules Centre at the University of Oxford's department of zoology, said in a statement. The extinct big, big cats turned out to be much more closely related to today's lions than jaguars or other living contemporaries in North America, according to the study.
To trace the genetic tree of these fearsome felines, researchers analyzed DNA from fossils from across the Northern Hemisphere – from Germany to Wyoming. They found that the Pleistocene-period (1.8 million - 10,000 years ago) lions living in Europe and Alaska were closer cousins than those living farther south in North America. The Oxford research team explains this by pointing to the Bearing land bridge, which connected Siberia and Alaska during the last ice age, allowing the cats to travel to North America from Eurasia. Ice sheets later cut off a path southward from Canada's Yukon, isolating the population to the south and eventually rendering it genetically distinct.
But after tens of thousands of years of hunting prey on the tundra, the lions, along with the mammoth and other massive mammals, died out about 13,000 years ago. "We still don't know what caused this mass extinction," study co-author Nobby Yamaguchi, a researcher at Oxford's Wildlife Research Conservation Unit, said in a statement, "although it is likely that early humans were involved one way or another."
They are surely joking. Humans are going to hunt out a one ton lion that routinely takes down Mammoths? Before the advent of the gun, the Grizzly hunted past the Mississippi and routinely hunted men. The mega lion is bigger and faster and strong. I do not figure how they got the 25% larger calculation. The skull size difference suggests something far larger and certainly able to possibly crush the vertebrate of a large animal.