What was the Biggest Mammalian land predator of all time?

If we include omnivores, was it Andrewsarchus, Sarkastodon, Arctocus simus (short faced bear) Megistotherium or Daeodon (Dinohyus)?

Forget Megatherium,(and other incidental meat eaters) though it seems to have scavenged dead Glyptodonts now and then. Modern hippopotami eat meat sometimes too.

The extant Polar Bear is a good candidate for largest mammalian land predator of all time... At least if we're talking pure predator, not omnivore. Top weight is about 700 kilo (almost 50% more than a grizzly!), or 100 kilos more than e.g. Andrewsarchus...

Arctodus simus is speculated to have been of about the same size as a polar bear.

Megistotherium was heavier, weighing perhaps as much as 900 kilos, but may have been more of an opportunist omnivore than a predator.

Some (rather dubious) estimates give weights of up to 900 - 1000 kilos for eurasic Cave Bear, but, again, this was an opportunistic omnivore a la Brown Bear.

In a fight my money would probably be on the cave bear or Megistotherium. Jokers in such a hypothetical fight might be the eurasic Cave Lion or the extant Sibirian Tiger, since although at 450 kilos they are much lighter than the above heavyweights, they are faster and better armed.

The most _efficient_ predator, bar none, in the history of Earth remains Homo sapiens, who tellingly enough likely drove three of the above species extinct, and the two remaining extant ones either threatened or critically endangered.

Humans aren't predators, they're infesting opportunistic omnivores. And I emphasize *infesting*.

Well... Yes, but there have been/are populations which are purely predatory, e.g. eskimos, and also historically the male role has been to kill big things (animals, especially other humans) whereas the females in addition to killing smaller things also collect plant material.

Nothing wrong with humans. I quite like them. Hell, some of my best friends are human. The problem is just that there's too darn many of

Did anything more ever come out related to the speculation a few years back that the giant ground sloth being a predator? Something about the location of sutures on the bone suggesting the possibility or rapid movement?

Exactly the point. I don't view individual humans as pests, but the species as a whole is one hell of an infestation...and a pretty unique one, as most other infesting species (cockroaches, rats, etc.) don't destroy everything they touch...unless it was rats who killed the

I've heard that it may have occasionally scavanged to suppliment its otherwise vegetarian diet. I always thought of the giant ground sloth as the therizinosaur of the cenozoic, personally. This kinda fits too since basal therians (probabl just like basal theropods) were primarily carnivorous omnivores. I wonder if therizinosaurs occasionally supplimented their diet with carrion?

Can you think of any land predator, aside from perhaps some of the snakes that do NOT go for the occasional 'aged and tender' food instead of the still-kicking prey? I'd almost consider suggesting that those snakes that 'see' in the IR as well as the visible might just not be able to recognize a dead mouse as food! You know, sort of like if it does not have the right IR signature it looks like a plastic 'play toy'.

Regards

I agree with you about the predators who prefer to eat that which doesn't put up much of a struggle. Even great white sharks, who are attracted to areas of high activity, will go for the prey that is most relatively inactive.

However my question was whether therizinosaurs, who were thought to be predators (like giant ground sloths) may have occasionally supplimented their otherwise vegetarian diet with carrion or even the occasional small animal (think gorillas)...kind of the reverse of carnivorous animals like dogs, lions, etc. who are primarily predatory but suppliment their otherwise carnivorous diet with grass, and other plant foods.

If you include omnivores, A. Simus is by far the largest mammalian land predator of all time. It stood 12 feet at the shoulder and weighed 2,500 lbs.

that is exactly what lajaboy wrote.