The Evolutionary Approach
15 Approaches to the Science of Psychology THE BIOLOGY OF EMOTION Robert Levenson, a psychologist at the University of California at Berkeley, takes a biological approach to the study of social interactions. He measures heart rate, muscle tension, and other physical reactions as couples discuss problems in their relationships. He then looks for patterns of physiological activity in each partner, such as overreactions to criticism, that might be related to success or failure in resolving their problems. researchers try to identify changes taking place in the brain as information is stored there. (Figure 6.13, in the chapter on memory, shows an example of these changes.) And when studying thinking, they might look for patterns of brain activity associated with, say, making quick decisions or reading a foreign language. Research discussed in nearly every chapter of this book reﬂects the enormous inﬂuence of the biological approach on psychology today. The Evolutionary Approach Mothers are solely responsible for the care and protection of their young in almost all species of mammals. These species survive without male parenting, so why are some human fathers so active in child rearing? Do evolutionary forces make fathering more adaptive for humans? Is it a matter of learning to care? Is it a combination of both? Psychologists who take an evolutionary approach study these questions and others relating to the origins of human social behavior. A FATHER’S LOVE evolutionary approach A view that emphasizes the inherited, adaptive aspects of behavior and mental processes. Biological processes are also highlighted in an approach to psychology that is based on Charles Darwin’s 1859 book, The Origin of Species. Darwin had argued that the forms of life we see today are the result of evolution—of changes in life forms that occur over many generations. He said that evolution occurs through natural selection, which promotes the survival of the ﬁttest individuals. Those whose behavior and appearance allow them to withstand the elements, to avoid predators, and to mate are able to survive and produce offspring with similar characteristics. Those less able to adjust, or adapt, to changing conditions are less likely to survive and reproduce. Most evolutionists today see natural selection operating at the level of genes, but the process is the same. Genes that result in characteristics and behaviors that are adaptive and useful in a certain environment will enable the creatures that inherited them to survive and reproduce, thereby passing those genes on to the next generation. According to evolutionary theory, many (but not all) of the genes that animals and humans possess today are the result of natural selection. The evolutionary approach to psychology assumes that the behavior and mental processes of animals and humans today is largely the result of evolution through natural selection. Evolutionary psychologists see aggression, for example, as a form of territory protection, and they see gender differences in mate selection preferences as reﬂecting different ways of helping genes to survive in future generations. The evolutionary approach has resulted in a growing body of research (Buller, 2005; Buss, 2004a); in later chapters, you will see how it is applied in relation to topics such as mental disorders, temperament, interpersonal attraction, and helping.