Three methodological approaches to studying animal behavior: observation: Observe and record the behavior of an organism without manipulating the environment or the animal. Method to describe behavioral patterns (ethogram) or test hypotheses. Multiple confounding factors: identity of individuals, motivational levels, temperature, ambient light conditions, etc. This method can identify associations between factors rather than cause effect relationships. Can"t conclude that adults air-drop urchins more frequently than juveniles: experimental: We manipulate or change a variable/s (independent variable) and measure a response (dependent variable). We often use one (or more) control group(s) to establish whether or not the manipulation is influencing the dependent variable. A control group does not experience the manipulation but it is treated similarly in all other aspects. This method may include co variates: variables we are not interested in manipulating, but we need to control for because of their potentially confounding effects on the dependent variable.