Heart Rate Patterns of Captive Asian Elephant in Their Natural Habitat

This study documented elephant cardiac function, confirming the low metabolic rate predicted by Kleiber's Law for large mammals. With heart rates averaging 30 bpm when standing (range 22-39 bpm), elephants demonstrate the efficiency gains that come with large body size.

The elephant serves as a key reference point in the book's comparison across the metabolic spectrum - from shrews at 1,500 bpm to elephants at 30 bpm, illustrating how size constrains metabolic rate through physics, not choice.