Ethology is the scientific and objective study of animal behavior, usually with a focus on behavior under natural conditions. Broadly speaking the manner in which an organism responds to various exogenous and endogenous stimuli is termed as behavior. The most complex behaviour patterns are the fixed action patterns. These are characterized by being unlearned, species specific and adaptive. They differ from reflexes and orientations in that they require an internal readiness before they can occur and the evoking stimulus. The releasing stimulus may be internal in the form of hormone secretion or an excitatory signal from a higher neural centre. The stimulus as external factors viz. light, temperature, substances produced by or activities other insects of the same species by releasers (stimulus). Light and temperature commonly determine whether an insect is active or inactive. Every insect species has a temperature below which or above which it becomes inactive and within the range of these temperatures.