In geology, the "missing link" popularly names a transitional fossil that fills an evolutionary gap between life forms, especially between apes and humans. In social psychology, Heider and Simmel (1944) demonstrated that humans are not the only targets perceived to be agents; people are ready to impute human characteristics even to geometric figures in nonrandom motion. Until recently, however, social cognition research has been focusing almost exclusively on perceptions of humans. This special issue demonstrates beyond a doubt the myriad ways that perceiving nonhuman agents and dehumanizing human agents can inform the boundaries of social cognition concerning people, providing missing links at both ends of social perception. One important way is by further illuminating "social" perception processes. Human perceivers often attribute human personality characteristics, autonomous will, and intentionality to nonhuman agents (anthropomorphism). And equally, human perceivers attribute nonhuman characteristics to other human agents (dehumanization). Interpersonal perception cannot be studied completely in isolation from the perception of nonhuman and dehumanized targets. The way we see other humans is inextricably intertwined with the way we see nonhumans. These complementary processes-anthropomorphism and dehumanization-provide conceptual bookends for social cognition research and theory.
