Final answer:
Animals that cannot create their own food and must eat other organisms for energy are called heterotrophs, which include consumers such as herbivores, carnivores, and omnivores, as well as decomposers.
Step-by-step explanation:
Understanding Heterotrophs in Biology
Animals that must find other organisms to eat in order to gain energy are known as heterotrophs. Unlike autotrophs, such as plants that can produce their own food through photosynthesis, heterotrophs depend on consuming other organisms. This group includes all animals, fungi, and many protists and bacteria.
Consumers are a specific type of heterotroph that actively eat other organisms. They can be further categorized based on their diet: herbivores eat plants, carnivores eat other animals, and omnivores eat both plants and animals. In contrast, decomposers like fungi and bacteria obtain energy by breaking down dead material and waste.
In essence, all heterotrophs rely on the energy initially captured by autotrophs through photosynthesis, creating an interconnected web of energy transfer within ecosystems.