Giant panda to digest cellulose is ascribed to the microbes in its gut. Pandas are born with sterile intestines and require bacteria obtained from their mother's feces to digest vegetation. The giant panda is a "highly specialized" animal with "unique adaptations", and has lived in bamboo forests for millions of years. The average giant panda eats as much as 9 to 14 kg (20 to 30 lb) of bamboo shoots a day to compensate for the limited energy content of its diet. Ingestion of such a large quantity of material is possible because of the rapid passage of large amounts of indigestible
Giant panda of durophagous carnivorans. It has evolved from previous ancestors to exhibit larger molars with increased complexity and expanded temporal fossa. A 110.45 kg (243.5 lb) giant panda has a 3D canine teeth bite force of 2603.47 newtons and bite force quotient of 292. Another study had a 117.5 kg (259 lb) giant panda bite of 1298.9 newtons (BFQ 151.4) at canine teeth and 1815.9 newtons (BFQ 141.8) at carnassial teeth. The giant panda's paw has a "thumb" and five fingers; the "thumb" – actually a modified sesamoid bone – helps it to hold bamboo while eating. Stephen Jay Gould discusses