An adult elephant consumes between 300 and 400 pounds (136–181 kg) of vegetation every single day — and spends up to 18 hours doing it. That extraordinary commitment to eating isn’t gluttony; it’s a biological necessity. Elephants have surprisingly inefficient digestive systems that absorb only around 40 percent of the nutrients in everything they eat, which means they must process enormous volumes of food just to meet their energy needs. Understanding what elephants eat reveals a great deal about how these animals shape the ecosystems they live in.