Roan antelope
Roan antelope are found in woodland and grassland savanna, mainly in the tropical and subtropical grasslands, savannas, and shrublands biome, which range in tree density from forest with a grassy understorey (such as central Zambezian Miombo woodlands) to grasslands dotted with few trees, where they eat midlength grasses. They form harem groups of five to 15 animals with a dominant male. Roan antelope commonly fight among themselves for dominance of their herd, brandishing their horns while both animals are on their knees.
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.