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The concept of bilateral symmetry in organisms involves the division of the body plan along a plane that splits the animal's body into right and left sides that are mirror images of each other. However can this be true for toe lengths and ratios? The present study evaluates the symmetric differences in toe length and toe-length ratios among the three major ethnic groups in Nigeria. A total of 1574 adult Nigerian Hausas (664), Igbos (420) and Yorubas (490) of equal sex were included in the study. Aged between 18-65 years, were randomly selected from various states. Written informed consent was taken from each participant, sample size was determined by proportion, using Cochran formulae for infinite population. A digital Vernier caliper was used to obtain direct linear measurements of the toe length of both feet; hallux (1T), second toe (2T), third toe (3T), fourth toe (4T), and the fifth toe (5T). Ten (10) possible toe-length ratios were also determined and named as follows; 1T/2T, 1T/3T, 1T/4T, 1T/5T, 2T/3T, 2T/4T, 2T/5T, 3T/4T, 3T/5T, and 4T/5T. Data were analyzed using SPSS (IBM®Armonk, New York, USA) and Minitab V17 (Minitab® Inc. State College, Pennsylvania) statistical software. Paired-sample t-test was used to evaluate symmetry; Pearson’s Correlation was used for inter-prediction of the toes and ratios. Confidence level was set at 95%; as P-values ≤0.05 were considered significant. The result showed that some of the toe length of both feet were significantly assymetrical among the studied ethnic groups; Hausa males (1T df=1.35 and 5T df=0.55; P<0.05) and females (1T and 3T; (1T df=0.27, 3T df=0.47) P<0.001), Igbo males (1T, 3T and 4T(1T df=0.47, 3T, df=-0.53, 4T df=-0.58) ; P<0.05 and females 1T and 3T(1T df=0.40, T3 df=-0.64) ; P<0.01) and Yoruba males(1T, 2T, 3T and 5T(1T df=1.29, 2T df=0.47, 3T df=0.15, and 5T df=0.55,); P<0.001) and females (1T and 5T(1T df=0.77; 5T df=0.23) ;P<0.001). The toe-length ratios also displayed symmetrical differences for Nigerian male population; 1T:2T [t=3.78, P<0.001], 1T:3T [t=6.27, P<0.001], 1T:4T [t=6.04, P<0.001], 1T:5T [t=2.43, P=0.015], 2T:3T [t=2.23, P=0.026], 3T:5T [t=-3.78, P<0.001] and 4T:5T [t=-3.77, P<0.001].For the female population, all ratios were not significantly different except for1T:4T [t=2.56, P=0.011]. However, both feet displayed significant positive association for co-estimation of the corresponding toe length and toe-length ratios (r-values ranging from 0.20-0.70 at P<0.05).Ethnic and sex specific asymmetry were observed in the toe length and toe-length ratios; thus suggesting that anthropometrically, organisms are not completely bilaterally symmetrical.Keywords: Asymmetry, Bilateral symmetry, Toe length, Toe-length ratio, Ethnic groups

Background: Effective surgical approaches and conclusive forensic investigations will require a well-documented comparative data for specific regions. This study was carried out to generate Nigerian specific morphometric data for the occipital condyle and basilar process and evaluate its application in forensic and clinical anatomy using macerated skull bones. Methods: A total of 141 adult Nigerian skull bones comprising of 126 males and 15 females were used for this study. . OC morphology was determined by shape and analysis was carried out using the Statistical package for Social Sciences (SPSS IBM® version 23) t-test was used in assessing sex differences in the measured parameters with confidence level set at 95% and P<0.05 was considered significant. . The paired sample t-test showed that only the MnOC width was bilateral, while OClength and MxOC width were significantly asymmetrical (P<0.001).The t-test showed that all variables except for OC length and MnOC width were significantly larger in males (P<0.05). When the dimensions of the Nigerian skull were compared with foreign values, high racial variability was observed and we had average OC length; not very short neither long, which was relatively safe for OC resection during surgical intervention at that region. Conclusion: It could be concluded that sex, side and racial differences are observable features of the occipital condyle and its morphometric relationship to other structures are useful to forensic experts and surgeons.

Background: Stature is a significant anthropometric determinant of the physical identity of an individual. Aim: This study was carried out to estimate stature of Nigerian Annang indigenes of Akwa Ibom State from hand and foot dimensions. Methods: Two hundred (200) adults Annang indigenes (100 male and female each) were randomly selected for this study. Hand and foot dimensions were obtained by direct linear measurements using a 150mm digital vernier caliper (with accuracy of 0.01mm); while stature was determined by stadiometric measurement of the height (to the nearest 0.1m). Measurements obtained include; second (2D), fourth digit (4D) and right foot length (RFL). All measurement were converted to centimeters (cm). SPSS (IBM® version 20, Armonk, New York, USA) t-test was to evaluate gender difference in the measured dimensions; while Pearson's correlation and Generalized Linear Modeling were used to derive Regression equation for estimation of stature from the measured dimensions. The significance level was set at 95% as P≤0.05 was considered significant. Results: The t-test showed that males displayed significantly higher mean values than the females for all measured parameters (P<0.001). Single regression sex specific regression formulae were derived and the result showed that better prediction (r) values were obtained for females F (2D=0.428, 4D=0.430, RFL=0.587; P<0.01) population when compared to males M (2D=0.319, 4D=0.231, RFL=0.456; P<0.05). Conclusion: This study suggests the existence of sexual difference in hand and foot dimension and also the possibility of accurately estimating stature from the right foot length, right second and fourth digit.