No Two Alike: Human Nature and Human Individuality

Science News, March 11, 2006

NO TWO ALIKE: Human Nature and Human Individuality JUDITH RICH HARRIS

Most people believe that they're the product of both their genes and their environments, or nature and nurture. Why, then, do conjoined identical twins, who have the same genes and the same environment, develop different personalities, hopes, and ambitions? What is really at the root of human individuality? Harris, an independent investigator, seeks answers beyond the nature-nurture debate, which she views as insufficient for explaining the development of personality. She first dispels many of the myths that surround human development, including, for instance, the idea that birth order has an effect on personality. She asserts that many of the current theories of development give too little weight to the influence of genes and heredity on behavior and that they don't correctly incorporate the effect of the environment. She cites classic psychology experiments with monkeys as well as cutting-edge research with DNA as evidence that there is more to the puzzle of human individuality than an interaction between genes and environment. Harris' view is that three systems--relationship, socialization, and status--interact to develop personality. These systems have evolved in people to prepare us for life outside our homes, as members of a society. Readers interested in evolutionary psychology and human development will find a lot to ponder here. Norton, 2006, 352 p., hardcover, $26.95.