Two ways that a deer depends on plants to survive

Deer eat several kinds of plants, but their main food item is browse. Browse is the growing tips of trees and shrubs.
Deer are ruminants. They initially chew their food only enough to swallow it. This food is stored in a stomach known as the “rumen.” From the rumen, food is regurgitated, then re-chewed before being swallowed again, entering a second stomach where digestion begins. From there it is passed into a third and then a fourth stomach, finally entering the intestine.

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