Shifting balance theory Shifting balance theory The shifting balance theory is a theory of evolution proposed in 1932 by Sewall Wright, suggesting that adaptive evolution may proceed most quickly when a population divides into subpopulations with restricted gene flow. The name of the theory is borrowed from Wright's metaphor of fitness landscapes (evolutionary landscapes), attempting to explain how a population may move across an adaptive valley to a higher adaptive peak. According to the theory, this movement occurs in three steps: Although shifting balance theory has been influential in evolutionary biology, inspiring the theories of quantum evolution and punctuated equilibrium, little empirical evidence
Prejudice from an evolutionary perspective Prejudice from an evolutionary perspective Prejudice can be considered from an evolutionary perspective. Evolutionary psychologists posit that our psychology, e.g. emotion and cognition, has not been uniquely isolated from the forces of evolution. Although there is psychological variation among individuals, the majority of our psychological mechanisms should be adaptations designed specifically to solve recurrent problems, many of which were social in nature, in our evolutionary history. To balance the costs and benefits of sociality we must be able to recognize and functionally respond to threats and opportunities (see James J. Gibson), and our errors in judgment should be biased toward