At birth, elephants have only two or three small cheek teeth. By the age of ten, big tectonic molars began to erupt in the back of their jaws, becoming part of a conveyer belt of teeth. As molars wear down near the front of an elephant’s mouth fragments of them break off in pieces and either fall out or are swallowed. Throughout its lifetime, an elephant will grow twenty-four molars in six sets – but only two tusks.
Each molar looks like a set of dishes drying edgewise on a rack, bonded together by enamel. The vertical ridges function like giant vegetable graters as an elephant’s lower jaw moves forward and back, rather than side-to-side like a cow. Each molar grows up to a foot long, has a maximum of ten ridges, and weighs eleven pounds apiece – perfect for grinding up tree branches.
Like human teeth, elephant teeth consist of cementum, dentine and enamel. Cementum holds the roots of a tooth in place, dentine surrounds the pulp and enamel crowns each tooth with a hard protective layer. Packed with nerves and blood vessels, the pulp cavities of elephant tusks extend two-thirds of the length of each tusk. Their teeth are as sensitive as mine are.
Doug asks Jabu to “Open up.” He curls his trunk back over his head and Doug stretches to his tiptoes, pulls his lower gums wide with his hands.
In his lifetime Jabu will have six sets of molars. His sixth set will wear down by the time he is sixty. Only ten percent of aging elephants grow a seventh set of molars.
“Very good, my boy. . . . veerrry good.”
Peering over Doug’s shoulder, I count four molars in his mouth, two on top and two on the bottom.
Doug lets go of Jabu’s lower jaw. “Allllright, Jabu, allllright.”
He drops his trunk but leaves his mouth open. Doug grabs a fistful of treats and slides his arm into Jabu’s mouth, all the way to his elbow. As he lets go of the treats he rubs Jabu’s tongue. He flaps his ears.
“Elephants use their trunks to rub each other’s tongues. It’s kind of like a handshake,” Doug says.