Herbivores and Carnivores
. In general, animals eat plants, other animals, or the remains of living things. Plant-eaters, or herbivores , often do not have to search far to find things to eat, and in some cases—for example wood-boring insects—they are entirely surrounded by their food. The disadvantage of a plant-based diet is that it can be difficult to digest and is often low in nutrients. To overcome the first of these problems, most herbivores have tough mouthparts for chewing and grinding their food. Many plant-eating animals, from termites to cattle , have complex digestive systems containing microorganisms that break down cellulose and other indigestible plant substances, turning them into nutrients that the animals can absorb. The second problem—lack of nutrients–is harder to sidestep, particularly in a diet made up largely of leaves. As a result, leaf-eaters often have to feed for many hours each day to obtain the nutrients that they need. Carnivores live on flesh from other animals that is often nu...