Experience, critical periods, and perceptual development perceptual systems results from both biological and experiential factors. Development of sensory and: genes program development, environment influences development. Genetic proof: if put on a visual cliff formed by a glass covered table that visually drops off beneath the glass, babies will not go over the cliff (i. e. to the drop") Cross-cultural research on perception perceptual abilities kind of perceptual learning experiences people have similarities than differences but some exist. There are more perceptual: show us that perception is influenced by experience. Muller-lyer illusion: people in other cultures do not fall for this illusion for the most part, their environment is not as filled with sharp corners, western perceptual hypothesis works in environment but not in this illusion. Cultural learning also affects perceptions of taste, odour, and texture: food in one culture may be nauseating and a delicacy in another.