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The Effect of Possible Allometric Interactions in Human Hand Digit Lengths on Sexual Dimorphism of Digit Ratios
1Department of Anthropology, Istanbul University, Istanbul, Turkey.
Objectives:
This study was conducted to determine whether possible allometries in hand digit lengths have an effect on the observed sexual dimorphism in digit ratios.
Methods:
The lengths of four digits from the second to the fifth digits on the right and left hands of 500 adult participants (250 males, 250 females) were measured and six different ratios were calculated. ANCOVA and regression analyses were used to examine the allometry effect.
Results:
The findings revealed that the sexual dimorphism that emerged in the right and left 2D:4D ratios was independent of the allometry effect. On the other hand, it was observed that the allometry effect emerged in the three digit ratios (right and left 2D:5D, left 3D:5D).
Conclusions:
These results reveal that the allometry effect is not observed on the ratios calculated from the digits (2D and 4D) that are claimed to have formed under the influence of prenatal steroids, but it can be observed on the other digits.
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