What makes up the bulk of the food (energy) source for the lion and the elephant?

Explanation:

Lions are large predatory carnivores that need to consume between 11-16 pounds of meat per day. The bulk of their food source consists of larger animals such as zebras, gazelles, buffalo, and even giraffes. On the other hand, Elephants are herbivores and consume most plant life surrounding them, eating roughly 300 pounds of food per day. The vast majority of Elephants eat mainly tall grasses, leaves, fruits, and even tree bark, but will eat any plant life they can find.