Includes bibliographical references (pages 285-316) and index.

The mystery of human personality -- Affective neuroscience personality scales and the big five -- Darwin's comparative "personality" model -- William McDougal's comparative psychology: toward a naturalistic personality approach -- A brief review of personality since McDougall: the need for a bottom-up model of personality -- Bottom-up and top-down personality approaches -- Our ancestral roots: personality research on great apes -- The special case of our canine companions -- Do rats have personalities? Of course they do! -- Animal personality summary -- Preludes to othe big five personality model: different paths toward understanding brainmind states that constitute human temperaments -- The big five: the essential core of Cattell's factor analysis -- The clarities and confusions of the big five -- The earlier history of biological theories of personality: Hans Eysenck, Jeffrey Gray, and Robert Cloninger -- Genetics and the origins of personality -- Human brain imaging -- Personality and the self -- Affective neuro-personality and psychopathology -- Fleshing out the complexities.