Physiological Adaptation:
Physiological adaptations are systemic internal responses to external stimulus that assist the body to maintain homeostasis. Sometimes it is difficult to recognise the physiological adaptations of the body. It actually affects the function of the body, not its shape.
For example, mutated organisms to protect against disease. Behavioural Adaptations refer as an action that the body takes to survive in its natural environment. Structural Adaptations denote the physical characteristics of the body that support it survive in natural environment.