What is a key characteristic of experimental research methods?

One key characteristic of experimental research methods is the manipulation of one or more variables. This approach allows researchers to establish cause-and-effect relationships by controlling conditions and systematically changing specific factors. For instance, in a behavioral study, a researcher might manipulate environmental conditions (like light or temperature) to observe how these changes affect an animal's behavior. This type of design is critical because it helps to identify what influences behavior directly, separating it from mere correlation that might occur in observational studies. The ability to test hypotheses through controlled experimentation is fundamental to advancing our understanding of animal behavior.