This emoji was part of the proprietary / non-standardized emoji set first introduced by Japanese carriers like Softbank. These emojis became part of the Apple iPhone starting in iOS 2.2 as an unlockable feature on handsets sold in English speaking countries.
Maslow's (1943, 1954) hierarchy of needs is a motivational theory in psychology comprising a five tier model of human needs, often depicted as hierarchical levels within a pyramid. Maslow stated that people are motivated to achieve certain needs and that some needs take precedence over others.
Maslow became the leader of the humanistic school of psychology that emerged in the 1950s and 1960s, which he referred to as the third force -- beyond Freudian theory and behaviorism. Maslow saw human beings' needs arranged like a ladder. The most basic needs, at the bottom, were physical -- air, water, food, sex.