What metabolic characteristic defines membership in Kingdom Animalia for organisms like the Whinchat?

Answer

Obtaining energy by consuming other organisms

The Kingdom Animalia is the broadest classification level mentioned, and its fundamental definition revolves around nutrition and cellular structure. Animals are defined as multicellular, eukaryotic organisms that must obtain necessary energy and nutrients by consuming other living or dead organisms; this metabolic strategy is known as heterotrophy. Unlike plants or photosynthetic protists, animals do not generate their own food internally, and they lack the rigid cell walls composed of substances like cellulose that are characteristic of plant cells, further distinguishing them within the hierarchy of life.

What metabolic characteristic defines membership in Kingdom Animalia for organisms like the Whinchat?
taxonomybirdclassificationscienceWhinchat