Maximum genetic proportion of metric traits from different regions of the skull in ancient human populations of Northwestern Argentina

VARELA H.H.; COCILOVO J.A.; VALDANO S.G

European journal of anatomy

Spanish Society of Anatomy

Año: 2020 vol. 24 p. 415 - 428

1136-4890

In order to explain the evolutionary process of ancient human populations that inhabited a specif-ic geographical region from quantitative skull traits, it is advisable to know the evolutionary potential of metric characters. For this reason, the proportion of the maximum genetic variance or maximum her-itability (h2m) of the variables studied was estimat-ed. In addition, it was evaluated whether h2m changes between regions of the skull (face, base and vault) and the degree of association between the phenotypic variance and the maximum genetic variance. Twenty-one symmetrical variables on the left and right sides of the skull were measured in 245 skulls from five prehistoric samples from northwestern Argentina. The upper limit of herita-bility was estimated using the repeated measure-ment method. To test whether there are differ-ences between the h2m of each group, the Kruskal-Wallis test was used. The maximum genetic val-ues of each variable were obtained through a re-gression analysis (right measure on left measure). The relationship between phenotypic and maximum genetic values was evaluated by correlation analysis. Significant bilateral difference is demon-strated in six of 21 characters. The average h2m is 0.77 and ranges between 0.58 and 0.93. The aver-age correlation between phenotypic values and maximum genotypic values was 0.8 (R2=0.65), suggesting that it is possible to make inferences of the genetic structure of the population from pheno-typic information. The high proportion of maximum observed genetic variance indicates an important evolutionary potential of the craniofacial complex in ancient populations of northwestern Argentina.