These family units are led by a matriarch, usually the eldest female. Males leave the family upon reaching adulthood, but visit occasionally. The males, or bulls, live together in loosely knit groups. They live as long as 70 years. The elephant's pregnancy is the longest of any mammal.
Many organizations work to save the elephant from extinction.
For a broader search of the topic, please see the NGS Publications Index . This information was prepared by the National Geographic Research Correspondence Division.