Lori Walton, age 12, of Ottawa, Ontario, Canada, for her question:

How old do elephants get to be?

As a general rule, larger animals tend to have longer life expectancies than smaller ones. Also as a general rule, captive animals tend to live longer than those exposed to the hazards of the wild. Hence we would expect a domestic elephant to live to a great age. And barring accidents, so he does. An Indian elephant, trained to work with man, has an average life span of 70 to 75 years. An African elephant, who insists on his right to live freely in the wild, has an average life span of about 50 years.

If his teeth were better, an elephant would live longer. He needs huge sturdy molars to grind up his enormous helpings of tough plant food. He has 24 of these teeth, though only a few are in working order at one time. As those near the front wear down, replacements move forward from the back of his jaws. When all 12 pairs of molars are chewed down to the gum, the elephant can no longer chew the food he needs to stay alive.