Have you “herd”? They’re enormous and intelligent, strong and sociable. Humans have been impressed by elephants for centuries, simply because they are so big—a male African elephant can weigh up to 7.5 tons (6.8 metric tons)! They also amaze us with their long and flexible noses, large and flapping ears, and loose, wrinkly skin. There are many stories about elephants—you’ve probably heard of Horton, Babar, and Dumbo. Elephants are one of the best-known animals in the world.

If all elephants seem the same to you, take a closer look. There are two types of elephants that are usually recognized: the African elephant and the Asian elephant. There is some ongoing debate about how many subspecies may exist, or whether some of these might, in fact, be species in their own right. Here are a few ways to tell them apart:

- African elephants have large ears that are shaped like the continent of Africa, both males and females have visible tusks, their skin is very wrinkly, their back is swayed, and the end of their trunk works as if they have two fingers there to help them pick things up. African elephants are the largest mammals on land.

- Asian elephants have smaller ears, usually only the males have visible tusks, their skin is not as wrinkly as African elephants’, they only have one “finger” at the ends of their trunk, and their back is dome-shaped.

Cool ears! An elephant’s ears are a like an air conditioner. As elephants flap their ears on a hot day, the blood flowing through the many blood vessels in the ears is cooled. If they have just splashed around in a river, all the better! This ear flapping behavior cools their large bodies on warm days.

The skinny on skin. The term “pachyderm” is from the Greek word pachydermos, which means “thick skinned,” and this term often refers to elephants, rhinos, and hippopotamuses.

An elephant’s skin can be up to 1 inch (2.54 centimeters) thick on some parts of its body. It’s also loose, which makes the elephant look like it’s wearing baggy pants or sagging stockings. But there’s a good reason for this—it keeps the animal cool by trapping moisture that takes longer to evaporate. And even though it’s thick, an elephant’s skin is also very sensitive to touch and sunburn. Elephants often spray themselves with water or roll in the mud or dust for protection from the sun and biting insects.

Really long in the tooth. Tusks are an elephant’s incisor teeth and are the only incisors an elephant has. They are used for defense, digging for water and food, and lifting things. The tusks present at birth are milk teeth, which fall out after a year when they are about 2 inches (5 centimeters) long. Permanent tusks extend beyond the lips at about two to three years and grow throughout the animal’s life.

The tusks are composed of ivory (dentine) beneath the outer layer of enamel, but the peculiar diamond pattern of the elephant’s tusk gives it a distinctive luster that ivory tusks of other mammals such as hippos, warthogs, walruses, and sperm whales don’t have, and African elephants are sometimes killed by poachers just for their ivory tusks.

Elephants also have four molars, one on the top and one on the bottom on both sides of the mouth. One molar can weigh about 5 pounds (2.3 kilograms) and is the size of a brick! Each elephant can go through up to six sets of molars in its lifetime.

New teeth do not erupt vertically, as in most mammals, but grow in from behind, pushing the old worn-out teeth forward and out, like a production line of teeth moving along the jaw from back to front. When elephants get old, their remaining molars are sensitive and worn down, so they prefer to eat softer food. Marshes are the perfect place for soft plant food, so old elephants are often found there. Many times they stay there until they die. This practice led some people to think that elephants went to special burial grounds to die.

The nose knows. An elephant’s trunk is both an upper lip and a nose. There are 8 major muscles on each side of the trunk and 150,000 muscle fascicles (portions of muscles) for the entire trunk. There are no bones or cartilage in this unique appendage. An elephant’s trunk is so strong it can push down trees and so agile that it can pick up a single piece of straw. Elephants also use their trunk like we use our hands: to grab, hold, pick up, reach, touch, pull, push, and throw.

The trunk is still a nose, too, and has two nostrils at the end that suck air up the long nasal passages and into the lungs. Elephants also use their trunks to drink, but the water doesn’t go all the way up the nose like a straw; instead, the elephant sucks water only part way up the trunk, curls it toward its mouth, tilts its head up, and lets the water from the trunk pour in.

Sounds of music. Elephants make many different sounds; humans cannot hear some of these sounds, as their frequency is too low for our ears. Elephants use these sounds to communicate with each other over long distances. Have you ever had your stomach growl at an unfortunate moment? Well, stomach growls are a welcome sound in elephant society; a stomach that makes loud rumbling and growling noises seems to signal to others that everything is “okay.”

The largest elephant on record was an adult male African elephant. He weighed about 24,000 pounds (10,886 kilograms) and was 13 feet (3.96 meters) tall at the shoulder! Most elephants don’t get that large, but African bush elephants do grow larger than Asian elephants.