We learn about Elephant Seals from Dr. Heather Liwanag, Associate Professor in the Biological Sciences at Cal Poly San Luis Obispo. She studies the physiological adaptations of animals to their environment, and Elephant Seals provide her with many remarkable features to study. 
The largest and deepest-diving pinnipeds in the world, Elephant Seals can be found on certain California beaches during their breeding season, when the males put on spectacular battle displays. At other times they are occasionally found hauled out when they molt. The rest of their lives are spent at sea, where they are only occasionally spotted as they come up for air between dives; they even sleep under water.