essay

1740 Words7 Pages
Assignment two
Much research has been conducted looking into the area of the human anatomy of the lengths of digits on the hand, particularly research into the 2D:4D digit ratio. The 2D:4D is a sexually dimorphic trait found in humans Hömekopp and Watson (2010 from a meat-analysis) and refers to the lengths of the 2nd digit/ finger (pointer) and the 4th digit/ finger (ring) and it is believed that this length is predisposed from exposure to different hormones in the utero Manning (2002). It has been hypothesized that the 2D:4D is a biomarker that is caused from parental testosterone and parental estrogenic Manning (2002) and is believed that a child’s 2D:4D is fully formed within the first 13 to 14 weeks of pregnancy (Phelps. 1952). Knickmeryer and Manning (2004) found a negative association of the ratio between testosterone and estradiol in the amniotic fluid, on the other hand high testosterone to estradiol levels have been associated with smaller 2D:4D digit ratios. On the other hand higher 2D:4D digit ratio has been associated with higher levels of estradiol to testosterone Manning et al (1998). It has also been found that males have a slightly smaller digit ratio to women Baile (2004).
The 2D:4D digit ratio has been liked with a plethora of human behaviours such as aggression (Manning, 2013) and gender identity (Kangassalo, 2011). However there has been much research into the length of the 2D:4D digit ratio and individual differences to self-perceived attractiveness, self-esteem and body- esteem; particularly in women (wade, 2003). One of the most influential psychologist exploring this area was Wade who hypothesised that women with a high 2D:4D digit ratio would find themselves more attractive. To test this hypotheses Wa...

... middle of paper ...

... T., Stewart, A., Bundred, P. E., & Trivers, R. L. (2004). Sex and ethnic differences in 2nd to 4th digit ratio of children. Early Human Development, 80 (2), 161 – 168

Manning, J.T., Scutt, D., Wilson, J., and Lewis-Jones, D.I. (1998). The ratio of 2nd to 4th digit length: A predictor of sperm numbers and concentrations of testosterone, luteinizing hormone and oestrogen. Human Reproduction,13 , 3000–3004
Manning, J. (2013). Digit Ratio (2D:4D), Aggression, and Testosterone in M en Exposed to an Aggressive Video Stimulus. Evolutionary Psychology. 11 (5), pp 953 - 964.

Kangassalo, k. (2011). Prenatal Influences on Sexual Orientation: Digit Ratio (2D:4D) and Number of Older Siblings. Evolutionary Psychology. 9 (4), pp 496-508.

Baile, A. (2004). Finger length ratio (2D:4D) correlates with physical aggression in men but not in women. Biological Psychology. 5 (1), 2-3.

More about essay

Open Document