Fluctuating asymmetry, relative digit length, and depression in men

Genetic and physiological stressors may compromise the development of the nervous system. Such factors may lead to an increased predisposition toward poor mental health. The purpose of this work was to investigate a possible link between (1) developmental instability (as measured by fluctuating asymmetry) and depression and (2) relative digit length (a possible marker for prenatal testosterone) and depression. Our sample consisted of 102 subjects (52 men and 50 women) and depression was measured by the Beck Depression Index (BDI), We found the BDI was positively related to fluctuating asymmetry in men but not women, i.e., asymmetric men reported more depression. Digit length (divided by height), particularly digit 4, was positively related to the BDI in men but not women. In men a tendency toward depression may be one cost associated with high prenatal testosterone concentrations, The evolutionary implications of these findings are discussed. (C) 1999 Elsevier Science Inc.