This video says about itself: ‘of all the battles that exist in the in the natural world none is more titanic than lions versus elephants’.
From LiveScience:
Carnivores Can’t Get Much Bigger
By Robin Lloyd
Senior Editorposted: 16 January 2007
Lions and tigers and bears are about as terrifying, size-wise, as it’s going to get in the wild world of mammals, new research shows.
Ecologists at the Zoological Society of London modeled the energy budgets of land-dwelling carnivores and arrived at a 1-ton limit as the maximum sustainable mass for these meat-eating mammals.
After that, there is a huge pay-off for each kill made by a large predator, but it takes too much lumbering energy for the behemoths to hunt the vast quantities of meat required to carry on across evolutionary time, said Chris Carbone, lead author of the new research published in the journal PLoS Biology.
At least four terrestrial, carnivorous mammals that Carbone puts near the 1-ton mark have gone extinct: the short-faced bear; North American lion; South American sabercat; and Megistotherium osteothlastes [see also here] (a wolf-like carnivore that lived 25 million years ago in Africa).
Today’s large carnivorous land mammals, including the record-setting polar bears [see Dutch poster here] —which usually weigh around half a ton but can grow to weigh nearly a ton, are threatened in part because of the energy intake-and-expenditure equation, Carbone told LiveScience.
“By being a carnivore that specializes on hunting big prey, it potentially can make you vulnerable to the process of extinction,” he said. …
The largest known land-dwelling carnivores of all time were lower-metabolism dinosaurs such as Spinosaurus (about 8 tons), Giganotosaurus (about 8 tons) and Tyrannosaurus (about 6 tons).
And then there was the 15-ton Indricothere—but that extinct mammal was an herbivore.
“Carnivores, because of the cost of hunting, can never achieve the sizes and intake rate of prey of the largest herbivores,” Carbone said.
See also here.
And here.
Size and aging in animals: here.
What keeps insects small? See here.
Evolution of skull and mandible shape in cats: here.
Carnivorous mammal evolution: here.
African lion populations declining steadily: here.
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