Studying the ratio of second finger (forefinger) to fourth one (ring finger) among ordinary people in south Khorasan province and comparing it with 2D:4D ratio of professional thieves in Birjand

Education Among humans, the length ratio of the second finger (2D) to the fourth finger (4D) is a sexual – dimorphism. The ratio of forefinger to ring finger among women is greater than men 9this ratio is lower for male humans, rats, baboons and finches while this ratio (2D:4D) is greater among Zebra fish males than females). 2D:4D ratio has a reverse relationship with concentration of testosterone prenatal. Therefore, 2D:4D ratio is seen as a proper indicator to examine the prenatal concentration of testosterone. Lower 2D:4D ratio indicates higher muscularity and it is accompanied with higher level of prenatal testosterone or sensitivity to androgen. In 2D:4D ratio, sexual – dimorphism is observed more in right hand than left one. In present paper, 2D:4D ratio in both right and left hands among 105 ordinary individuals and 105 professional thieves sentenced in Birjand Central Jail are studied by using digital calipers (0.01mm) and data collection through questionnaire and by using SPSS16 software package and t-test. Findings indicate that 2D:4D ratio among professional thieves sentenced in Birjan Central Jail is less than ordinary people (P<0.05). Based on this finding, it is too likely that the amount testosterone among thieves is higher than ordinary population and thieved are likely commit offence due to further manly hormones.