Your finger length, handedness & chirality! (part2)

Handedness & your finger length ratio While a few years ago early studies had identified a link between various hand characteristics and handness, last year the link was ‘officially’ confirmed in an Australian study that had used a new method for measuring finger length ratio. Now a new BBC internet study by the ‘finger professor’ John T. Manning has confirmed the earlier findings. TITLE OF THE STUDY: Digit ratio (2D:4D) and hand preference for writing in the BBC Internet Study. SUMMARY OF THE STUDY: “The ratio of the length of the second to the fourth digit (2D:4D) may be negatively correlated with prenatal testosterone. Hand preference has been linked with prenatal testosterone and 2D:4D. Here we show that 2D:4D is associated with hand preference for writing in a large internet sample (n>170,000) in which participants self-reported their finger lengths.” “We replicated a significant association between right 2D:4D and writing hand preference (low right 2D:4D associated with left hand preference) as well as a significant correlation between writing hand preference and the difference between left and right 2D:4D or Dr-l (low Dr-l associated with left hand preference).” “A new significant correlation between left 2D:4D and writing hand preference was also shown (high left 2D:4D associated with left hand preference). There was a clear interaction between writing hand preference and 2D:4D: The left 2D:4D was significantly larger than the right 2D:4D in male and female left-handed writers, and the right hand 2D:4D was significantly larger than the left hand 2D:4D in male and female right-handed writers.” READ FURTHER ABOUT FINGER LENGTH & HANDEDNESS: The origins of handedness Your fingers reveal so much about you The finger book – BOOK Your left handed child – BOOK

Your finger length, handedness & chirality!

Handedness is not only seen in human beings, it is also an important concept in biology: all amino acids that make up proteins in all living things are 100% left-handed!

Handedness & your finger length ratio: Earlier this year researchers from the University of Melbourne have tested a new method of measuring Mannings ‘finger ratio’. They e.g. found in the hands of 600 students that the hands of right-handed students are characterized by longer fingers in the right hand (compared to the left hand).

Interestingly, the researchers also observed an effect between hand preference and the index/ring finger ratio. Left-handed subjects appeared to have a more ‘masculine pattern’: they had a lower 2D:4D ratio compared to right-handed subjects. This implicates that relative finger length can predict a person’s gender or their hand preference! The method of measuring the ‘finger length ratio’ included a tube-test, which was compared with measurements on photocopied hands. The tubes test yielded a longer estimate of ring finger length compared to the photocopy method. Despite this, there was a strong correlation between the tests and both showed an association with gender. By the way, the link between handedness (laterality) and right-left finger length difference was already noticed a few years ago by a Dutch psychologist, who described that the combination leftward thumb length, finger length & handpalm asymmetry can provide a strong indication for left handedness. READ FURTHER ABOUT FINGER LENGTH & HANDEDNESS: Left handed men may think more like women The origins of handedness Your fingers reveal so much about you Your left handed child – BOOK The finger book – BOOK * Source: Laterality