Xenophagy

Xenophagy (Greek "strange" + "eating") and allotrophy (Greek "other" + "nutrient") are changes in established patterns of biological consumption, by individuals or groups.
• In entomology, xenophagy is a categorical change in diet, such as an herbivore becoming carnivorous, a predator becoming necrophagous, a coprophage becoming necrophagous or carnivorous, or a reversal of such changes. Allotrophy is a less extreme change in diet, such as in the case of the seven-spot ladybird, which can diversify a diet of aphids to sometimes include pollen. There are several apparent cases of allotrophy in Israeli Longitarsus beetles.