Bears of the Pleistocene

[Spalea]

(04-01-2018, 11:43 AM)brotherbear Wrote: Concerning the grizzly and the Pleistocene predators: Epiphany... I am having second thoughts on the entire intraspecific relationship teachings about Pleistocene predators of N. America. Besides the grizzly, there were three large bear species living in N. America, the black bear, the vegetarian Florida cave bear, and the giant short-faced bear. Now, I believe that the giant could chase any other predator from a carcass. But, I do not consider the giant to be a predator. He simply wasn't built for chasing down large prey animals. Besides, there were a multitude of large predators doing the hunting and killing which provided meat for the giant. Therefore, it was a simple matter for the grizzly to simply stay out of the giant's space.
No, not the giant bear. It was the wolves, both grey wolf and dire wolf which made life drastically hard for the she-bear with cubs. And, it were the big cats that hunted and killed sub-adult grizzlies. Giant jaguar, scimitar cat, atrox lion, and prides of saber-toothed cats. It probably was not the giant bear that preyed upon the grizzly, but rather the large full-time predators. Just as with the Amur tiger and the Ussuri brown bear in the R.F.E., the big cats of Pleistocene N. America probably preyed upon juvenile grizzlies and perhaps on occasion an adult she-bear. Even the occasional mature grizzly boar might possibly have fallen victim to a pride of saber-tooths from time to time.

I take back your last sentence: "Even the occasional mature grizzly boar might possibly have fallen victim to a pride of saber-tooths from time to time."

Let us imagine a pride of hungry atrox lions patrolling the deserted snowy, beaten by the winds, landscape of the North American: 2 or 3 males, weighing between 300 and 350 kilos, 3 or 4 females between 180 and 250 kilos. Honestly, even a full mature male grizzly, weighing 400- 500 kilos (I imagine the Pleistocene grizzlys, being not yet harassed by the human predation, noticeably bigger than the extant ones), would flee swiftly such a coalition.

Perhaps, I am overrating the predation capacities of the atrox lions, but, apart their big size, they were endowed with a big cranium, showing so a bigger brain than the extant big pantera felids' one. A fact is: we have found a lot of sabertooth cats well preserved in the quicksand where they got stuck, but very few atrox lions in the same case. Perhaps these felids didn't fall into these traps.

This is the possibility that the pride of atrox lions took progressively the place of the sabertooth cats, becoming so the main pure predators within the Pleistocene of the North America. The giant short-faced bear being the ultimate scavenger, the only one able to rebel against them around a big corpse. Reply