For many decades, the precise taxonomic classification of the giant panda was under debate. It shares characteristics of both bears and raccoons. However, genetic testing has revealed that giant pandas are true bears and part of the Ursidae family. Its closest bear relative is the spectacled bear of South America.
The giant panda has an unusual paw, with a "thumb" and five fingers; the "thumb" is actually a modified wrist-bone. Stephen Jay Gould wrote an essay about this, then used the title The Panda's Thumb for a book of collected essays.
Despite being taxonomically a carnivore, the giant panda's diet is overwhelmingly herbivorous. In fact, it lives almost entirely on bamboo. Yet like many animals, they are omnivores, as pandas have been known to eat eggs, and they consume some insects as necessary sources of protein. Their ears wiggle when they chew.