While the largest prehistoric mammals never came close to the size of the largest dinosaurs (tens of millions of years before them), they were pound by pound much more powerful than any elephant, pig, hedgehog, or tiger alive today.
The largest terrestrial herbivore - Indricotherium (20 tons)
Of all the prehistoric mammals on this list, Indricotherium (also known as Paraceratherium and Baluchitherium) is the only giant sauropod that dates close to tens of millions of years ago.
Despite its longer neck, its legs are also relatively slender and it has three-toed feet. But this 20-ton Pliocene beast is indeed the ancestor of the modern (weighing a ton) rhinoceros.
The largest sloth - Behemoth (3 tons)
Along with the glyptodon, the giant beast, aka the giant sloth, was one of the countless giant mammals of South America during the Pleistocene.
For most of the Cenozoic era, South America broke away from the evolutionary mainstream, with abundant vegetation that allowed its mammal population to grow to a truly massive size. Its long claws are a clue that the behemoth is tearing leaves from trees for most of the day, but the three-ton sloth may not be averse to occasionally preying on rodents or snakes.
The largest elephant - the steppe mammoth (10 tons)
Also known as Mammuthus trogontherii – thus making it another mammoth genus, M. A close relative of Primigenius, aka the woolly mammoth, the steppe mammoth may have weighed up to 10 tons, so prehistoric humans could not reach its Middle Pleistocene Eurasian habitat.
Sadly, if we cloned a mammoth, we would have to satisfy the nearest mammoth, as quick-frozen specimens of steppe mammoths are known to exist.
Largest rhino - (4 tons)
Could a 20-foot-long, 4-ton rhinoceros be the source of unicorn lore?
This giant rhinoceros, with an equally massive three-foot-long horn at the end of its nose, undoubtedly frightened (and captivated) the superstitious early humans of late Pleistocene Eurasia.
Like its contemporary slightly smaller long-haired rhinoceros, the plate-skinned rhino is covered in thick fur, making it a favorite of any Homo sapiens who needs a warm coat.
Largest armadillo - Glyptodont (2,000 lb)
Modern armadillos are tiny, harmless creatures that curl up into a softball-sized mass if you look directly at them.
This is not the case with the modern armadillo, which is an armadillo weighing up to a ton and roughly comparable in size and shape to the classic mass beetle.
Surprisingly, early human settlers in South America occasionally used the shells of glyptodonts to escape the bad weather—and also hunted the gentle creature for its meat until it became extinct, which could feed entire tribes for days.
Largest terrestrial carnivore - Andrews dragon (2,000 lb)
The famous fossil hunter Roy Chapman Andrews discovered a single giant skull reconstructed Andrewsarchus during an expedition to the Gobi Desert.
It is 13 feet long and weighs a ton, and is likely to feed on megafauna mammals such as thunder beasts ("thunder beasts").
Given its huge jaws, Andrews Dragon may also have bitten through the hard shell of an equally huge prehistoric turtle to supplement the diet!
The largest whale - the king whale (60 tons)
Unlike the other mammals on this list, the dragon king whale cannot claim to be the largest of its kind — a honor that goes to the living blue whale, which can grow up to 200 tons.
But in the mid-Miocene, weighing around 60 tons, the dragon king whale was undoubtedly the largest prehistoric whale ever built, even weighing 10 or 20 tons more than the much later Leviathan.
The largest marine mammal - Steller's manatee (10 tons)
During the Pleistocene period, boatloads of kelp were scattered along the North Pacific coast – which helps explain the evolution of the Steller manatee, a 10-tonne, kelp-feeding dugong ancestor that lasted until the 18th century when it became extinct.
This not-so-bright marine mammal (its head, almost ridiculously small relative to its huge body) was hunted to oblivion by European sailors.
The largest marsupial - Didendrodont (2 tons)
Diprotodon is also known by its more evocative name, the giant wombat, a two-ton marsupial that staggered through vast areas of Pleistocene Australia to nibble on its favorite snack, the salt bush.
(The giant marsupial chased its plant prey so single-mindedly that many drowned after breaking through the salt-shell lake.) Like other giant marsupials in Australia, the diplodont thrived before the arrival of early humans, who hunted it to extinction.
The largest bear - the bighorn (2 tons)
Three million years ago, at the end of the Pliocene, the Isthmus of Mesoamerica rose from the depths of darkness, creating a land bridge between North and South America. That's when a herd of bighorns (aka giant short-faced bears) travels south and eventually continues to lay eggs for truly impressive two-ton bighorns.
The only predator that prevents the bighorn from replacing it as the largest land mammal is its supposed fruit and nut diet.
Largest cat – Ngandong tiger (1,000 lb)
In the village of Ngandon, Indonesia, the Nkandon tiger found is the predecessor of the extant Bengal tiger.
The difference is that the male Ngandong tiger may have grown to as much as 1,000 pounds, as paleontologists have also found the remains of oversized cattle, pigs, deer, elephants, and rhinos in this part of Indonesia — all of which are likely to be on the dinner menu of this fearsome feline.
Largest Dog - Dire Wolf (200 lb)
In a way, it is unfair to classify the dire wolf as the largest prehistoric canine after all, and some "bear dogs" further down the canine evolutionary tree. There is no doubt that the Pleistocene dire wolf was the largest prehistoric dog and actually looked like a dog, but was at least 25% heavier than the largest dog breed in existence today.
Largest Rodent - Joseph Artegasia (2,000 lbs)
Do you think you have a mouse problem? Good luck you didn't live in early Pleistocene South America, where the 10-foot-long, one-ton Joseph Artegasia spread rodent-hating hominids onto the top branches of tall trees.
Joseph Artigasia, despite her huge size, does not feed on brie cheese, but on soft plants and fruits – its oversized incisors may be a sexually selective trait (that is, males with larger teeth are more likely to pass on their genes to offspring).
Largest Rabbit - Nura Ragus (25 lbs)
If you're a certain age, you probably remember the Carbanno rabbit from the classic movie Monty Python and the Holy Grail, a seemingly harmless rabbit that decapitated a group of overconfident knights.
Despite its size, Nularagus has a hard time jumping effectively, and its ears (ironically) are much smaller than those of the average Easter Bunny.
The largest camel - Titanosaurus (2,000 lbs)
Formerly (more intuitively) known as Titanosaurus, the one-ton Titanosaurus ("giant knotted feet") was by far the largest camel in Pleistocene Eurasia and North America.
Like many of its contemporaries in megafaun mammals, Titanosaurus had an unusually small brain and its wide, flat feet were ideal for navigating rough terrain. (Surprisingly, camels originated in North America and appeared in Central Asia and the Middle East after millions of years of migration.) ）
Largest lemur - lemur (500 lbs)
Considering the prehistoric rabbits, mice, and armadillos you've already encountered on this list, you probably won't be overly worried about lemurs.
This is a Pleistocene Malagasy lemur that grew to the size of a gorilla. The slow, gentle, and not so intelligent lemur pursued a sloth-like lifestyle to the point that it looked a bit like a modern sloth (a process known as convergent evolution).
Like many megafaunal mammals, Archaeoindris was hunted to extinction by the first human settlers of Madagascar shortly after the last ice age.
The largest ape - Great Ape (1,000 pounds)
Perhaps because its name is too similar to Australopithecus, many people mistake the great ape for a primitive man, a branch of Pleistocene primates of the direct ancestor of humans.
But in fact, this is the largest ape ever made, about twice the size of a modern gorilla, and potentially more aggressive. (Some occult zoologists believe that the creatures we call Bigfoot, Bigfoot, and Yeti are still living adult great apes, and they have not produced a shred of credible evidence for this theory.) ）
Largest Hedgehog - Hedgehog (10 lbs)
Hedgehogs share the same Greek roots as "dinosaurs," and for good reason – this Miocene mammal was 2 feet long and weighed 10 pounds, making it the largest hedgehog in the world (modern hedgehogs weigh several pounds maximum).
A classic example of what evolutionary biologists call "island gigantism" is that hedgehogs grow larger after their ancestors were stranded on a group of islands off the coast of Europe, with few natural predators.
Largest Beaver - Giant Beaver (200 lbs)
Did the 200-pound beaver, also known as the giant beaver, build an equally massive dam?
That's a question many have asked when they first learned about this Pleistocene mammal, but it's frustrating that the truth is elusive.
In fact, even modern, reasonably sized beavers can build huge structures out of twigs and weeds, so there's no reason to believe that beavers will build huge dams – but you have to admit it's a striking image!
Largest Pig - Big Orton (2,000 lb)
Surprisingly, no environmentalist keen on barbecue considered "going extinct" with Big Orton, because a single spitting specimen of this 2,000-pound pig was enough to supply a small Southern city with enough pulled pork.
Also known as the "terrible pig," Big Orton looked more like a modern warthog than a traditional farm pig, which had a broad, flat, mottled face and protruding front teeth; This giant animal mammal must be very adapted to its North American habitat, as various species have persisted for over 10 million years!