In behavior analysis it is crucial to distinguish between factors that influence an organisms characteristics and behaviors Phylogenic traits refer to characteristics that are a product of an organisms evolutionary history and genetic endowment These are innate inherited traits passed down through biological mechanisms such as the physical features described dark hair dark eyes small noses They are part of an individuals biological nature and are not acquired through learning during their lifetime In contrast ontogenic traits or behaviors are those that are developed or modified through an individuals learning history resulting from their interactions with the environment ie antecedents and consequences shaping behavior Respondent behaviors are elicited by specific antecedent stimuli and are typically involuntary eg salivating to food blinking to a puff of air and elicited behaviors is another term for respondent behaviors Since the question specifically refers to inherited physical characteristics phylogenic traits is the most accurate classification