ABSTRACT
This chapter explains the history of personality measurement, the question of personality in animals and the relationship between evolution and intelligence. Personality theory is a big topic within psychology, and methods such as factor analysis have enabled researchers to measure the personality types of individuals using questionnaires. Frequency dependent selection in evolutionary theory that states that the effectiveness of a given phenotype, whether or not it is selected, is dependent upon the nature of other phenotypes within a population there is some evidence that genes are involved in the development of both personality and intelligence. Behavioural geneticists study the degree to which differences between people can be attributed to difference between them in their genes. Evolutionary psychology has only just begun to apply itself to the topic of individual differences in personality, and as a result good, hard evidence for the potential evolutionary benefits is rather thin on the ground at the moment.
