Whales are really big, and a hippopotamus is roughly the same size as a rhinoceros. But do you know the biggest mammals by category? Here's a list of the 20 biggest mammals, in 20 categories, starting with the biggest whale and ending with the biggest shrew:
Biggest Whale: Blue Whale (200 Tons)
At 100 feet long and 200 tons, not only is the blue whale the biggest mammal in the world, but it's also the largest vertebrate animalthat has ever lived. Not even the largest dinosaurs approached it in bulk. Some titanosaurs were over 100 feet long, but they didn't weigh 200 tons. Fittingly, the blue whale is also the loudest animal on earth. This cetacean can vocalize at 180 decibels, enough to render most other animals deaf.
Biggest Elephant: African Elephant (7 Tons)
The largest land-dwelling mammal on earth, at seven tons, the African elephant is smaller than the blue whale for good reason: The buoyancy of water helps to counteract the blue whale's weight, and elephants are terrestrial. One reason the African elephant has enormous ears is to help dissipate its internal body heat. A warm-blooded, seven-ton mammal generates a lot of calories.
Biggest Dolphin: Killer Whale (6 to 7 Tons)
How can the biggest dolphin be a whale?Killer whales, also known as orcas, are classified as dolphins rather than whales. At six or seven tons, male orcas are bigger than the largest sharks, which means that killer whales, rather than great white sharks, are the atop predators of the oceans. Sharks have a more fearsome reputation because very few humans have been killed by killer whales.
Biggest Even-Toed Ungulate: Hippopotamus (5 tons)
Even-toed ungulates, or artiodactyls, are a widespread family of plant-eating mammals that includes deer, pigs, cows, and the biggest cleft-hoofed mammal, the common hippopotamus. The pygmy hippopotamus doesn't approach its cousin's five-ton heft. You could make a case for another even-toed creature, the giraffe, which is much taller than a hippo, but they weigh only two tons.
Biggest Odd-Toed Ungulate: White Rhinoceros (5 tons)
Perissodactyls, or odd-toed ungulates, aren't as diverse as their even-toed cousins. This family consists of horses, zebras, and tapirs on the one hand and rhinoceroses on the other. The biggest perissodactyl is the white rhinoceros, which at five tons rivalsPleistocene rhinoceros ancestors such as theElasmotherium. There are two types of white rhinos, the southern white rhinoceros and the northern white Rhinoceros; it's easy to figure in what part of Africa they reside.
Biggest Pinniped: Southern Elephant Seal (3 to 4 Tons)
At up to four tons, not only is the southern elephant seal the biggest pinniped alive, but it's also the biggest terrestrial meat-eating mammal, outweighing the largest lions, tigers, and bears. Male southern elephant seals vastly outweigh females, which top out at two tons. Like blue whales, male elephant seals are extraordinarily loud; they bellow their sexual availability from miles away.
Biggest Bear: Polar Bear (1 Ton)
If you're under the illusion that polar bears, grizzly bears, and pandas are comparable in size, you're wrong.Polar bears are by far the biggest—and deadliest—ursines. The largest males can reach a height of 10 feet and weigh up to a ton. The only bear that comes closeis the kodiak bear; some males can reach 1,500 pounds.
Biggest Sirenian: West Indian Manatee (1,300 Pounds)
Thesirenians, the family of aquatic mammals that includes manatees and dugongs,are distantly related to pinnipeds and share many characteristics. At 13 feet long and 1,300 pounds, the West Indian manatee is the biggest sirenian by an accident of history: A bigger member of this breed, Steller's sea cow, went extinct in the 18th century. Some of them weighed 10 tons.
Biggest Equid: Grevy's Zebra (1,000 Pounds)
The genus Equus comprises not only horses but also donkeys, asses, andzebras. While some domesticated horses exceed 2,000 pounds, Grevy's zebra is the world's largest wild equid; adults reach half a ton. Like many other animals on this list, Grevy's Zebra is nearing extinction; there are probably fewer than 5,000 in scattered habitats in Kenya and Ethiopia.
Biggest Pig: Giant Forest Hog (600 Pounds)
How big is the giant forest hog? This 600-pound pig has been known to chase African hyenas from their kill, though it's sometimes preyed on by the largest African leopards. Despite its size, the giant forest hog is relatively gentle. It is easily tamed, if not outright domesticated, and can live alongside humans. It'smostly a herbivore, scavenging meals only when it's especially hungry.
Biggest Cat: Siberian Tiger (500 to 600 Pounds)
Male Siberiantigersweigh a whopping 500 to 600 pounds; females reach 300 to 400 pounds. Only 500 or soSiberiantigersstill live in eastern Russia, andcontinuing ecological pressure may strip this big cat of its title. Some naturalists claim that Bengal tigers have surpassed their Siberian relatives, since they're not as endangered and are better fed. There may be as many as 2,000 Bengal tigers in India and Bangladesh.
Biggest Primate: Eastern Lowland Gorilla (400 Pounds)
There are two contestants for world's largest primate: theeastern lowland gorilla and the western lowland gorilla. Both live in the Congo, and by most accounts, the 400-pound eastern variety has the edge on its 350-pound western cousin, though western lowland gorillas outnumber the eastern variety by a 20-to-1 ratio.
Biggest Canid: Gray Wolf (200 Pounds)
Although some domesticated dog breeds grow larger, the consistently beefiest species of genus Canis is the gray wolf.Full-grown wolves often reach 200 pounds. Gray wolves mate for life.
Biggest Marsupial: Red Kangaroo (200 Pounds)
The red kangaroo of Australia reaches five and a half feet tall and 200 pounds, making it the largest marsupial. That's notsaying much considering the enormous sizes of its ancestors. The giant short-faced kangaroo weighed 500 pounds, and the giant wombat reachedtwo tons. Male red kangaroos are much bigger than females and can cover almost 30 feet in a single leap.
Biggest Rodent: Capybara (150 Pounds)
A full-grown capybara, a South American rodent closely related to guinea pigs, can reach 150 pounds. But the capybara isn't the largest rodent that ever lived. The hippopotamus-size Josephoartigasia weighed a whopping two tons.
Biggest Armadillo: Giant Armadillo (100 Pounds)
During the Pleistocene epoch, armadillos were the size of Volkswagen Beetles. Abandoned shells of the one-ton Glyptodonwere used by early humans as shelter. Today, this comical-looking breed is represented in the record books by the 100-pound giant armadillo of South America.
Biggest Lagomorph: European Hare (15 Pounds)
The 15-pound European hare is by far the world's biggest lagomorph,a family that includes rabbits, hares, and pikas. European hares put their heft to good use: In the spring, females can be seen rearing back on their hind legs and swatting males in the face, either to refuse an invitation to mate or to see what kind of stuff their prospective mates are made of.
Biggest Hedgehog: Greater Moonrat (5 Pounds)
The five-pound greater moonrat,native to Indonesia, emits a strong, ammonia-like odor, hisses menacingly to keep enemies at bay, and prefers to live alone, except during mating season.The greater moonrat isn't much smaller than theDeinogalerix, a giant hedgehog of the Pleistocene epoch.
Biggest Bat: Golden-Capped Fruit Bat (3 Pounds)
"Megabat" is the term naturalists use to describe any bat weighing more than a few ounces, and no megabat is larger than the golden-capped fruit bat of the Philippines, also known as the giant golden-capped flying fox. Fortunately for humans, fruit bats are strictly herbivorous, and they also lack the common bat's ability to echolocate, or to finddistantprey by emitting sound waves reflected back to them.
Biggest Shrew: Hispaniolan Solenodon (2 Pounds)
The Hispaniolan solenodon, whichlives on Hispaniola, the island shared by Haiti and the Dominican Republic, can reach two pounds, which may not sound like much until you realize that the vast majority of shrews weigh only a few ounces. Fortunately for the Solenodon, Hispaniola has few predators that could make it lunch.