Yellow-backed duiker
These forest dwelling antelope feed selectively on plants or plant parts such as shoots, roots, leaves, and buds, but their diet is mainly made up of fruits. The yellow-backed duiker is more efficient at digesting poor quality food than most other duiker species. This allows them to eat large, low quality fruits. Their diet makes them very hard to keep in captivity as most domesticated fruits are not well suited to their low fiber requirements. They are considered concentrate selectors, meaning they eat "diets relatively low in fiber, have a well developed ability to forage selectively, a rumen bypass, a rapid passage and high fermentation rate for starch, and they frequently encounter toxins."
Foothill yellow-legged frog
Food supplies, such as algae the tadpoles eat, also affect the sexual maturity of the species. Reportedly, the "amount of protein in different algae, can affect size at and time to metamorphosis" and "these food effects may be mediated through diet-induced changes in thyroid function", which means the food the tadpoles ingest dictates the changes in the thyroid gland's production of certain proteins. Tadpoles most commonly feed on algae, diatoms, and detritus. As the species grows older, it changes its diet to animal tissue which must be swallowed whole because the frog's jaw is structured on a hinge joint that does not allow for sideways movement as in humans. Adult frogs eat a range of foods such as moths, ants, grasshoppers, hornets, beetles, flies, water striders, and snails.