Evolutionary psychology The study of the evolution of behavior using principles of natural selection. Related Articles: Fashion? Who cares?Fashion conveys the way we feel, think about ourselves and our behavior and in-turn the way that people convey us and how they behave around us! Sasha Co- Founder of Psych n Sex, previous writer and campus educator for the Kinsey Institute & published psychology researcher. Manhattan girl obsessed with post ww2 abstract expressionism, beet juice, vintage clothing & Scandinavia.