Non-Metric Traits. An Assessment of Cranial and Post-Cranial Non-Metric Traits in the Skeletal Assemblage from the 17th-19th Century Churchyard of Middenbeemster, the Netherlands.

Skeletal non-metric traits (NMTs) are minor morphological variants that are often used by osteoarchaeologists to determine genetic affiliation between past populations (biodistance). Some NMTs are heavily affected by environmental factors, especially habitual physical activities, whereas others have a genetic cause. This study introduces the novel application of subdividing NMTs into a mechanical, genetic, and ambiguous category, to elucidate traits of different heritability. This method is applied to a sample of 93 well-preserved adult skeletons from the 17th-19th century AD cemetery of Middenbeemster, the Netherlands. Twenty-six cranial and post-cranial skeletal NMTs were examined to determine: 1) whether significant differences in NMTs between males and females, and different age groups were present, 2) whether significant differences in mechanical NMTs versus genetic NMTs were present in the Middenbeemster sample, and 3) whether there was more variation in mechanical versus...Show moreSkeletal non-metric traits (NMTs) are minor morphological variants that are often used by osteoarchaeologists to determine genetic affiliation between past populations (biodistance). Some NMTs are heavily affected by environmental factors, especially habitual physical activities, whereas others have a genetic cause. This study introduces the novel application of subdividing NMTs into a mechanical, genetic, and ambiguous category, to elucidate traits of different heritability. This method is applied to a sample of 93 well-preserved adult skeletons from the 17th-19th century AD cemetery of Middenbeemster, the Netherlands. Twenty-six cranial and post-cranial skeletal NMTs were examined to determine: 1) whether significant differences in NMTs between males and females, and different age groups were present, 2) whether significant differences in mechanical NMTs versus genetic NMTs were present in the Middenbeemster sample, and 3) whether there was more variation in mechanical versus genetic NMT frequency between Middenbeemster and comparative groups of the same ethnicity. It is expected that mechanical NMTs would exhibit more variation than genetic NMTs, since it is thought that activities vary more between groups than their genes. No statistically significant differences in NMT frequency were present between males and females, or among age categories. No statistically significant differences were observed between the genetic and mechanical NMT categories in the Middenbeemster sample. Finally, no significant differences were encountered when comparing Middenbeemster to comparative assemblages. The results are affected by a small sample size, and the lack of comparative samples with frequency data for many NMTs. Future research using this categorisation can provide insight in highly heritable NMTs, which will improve the accuracy selection of biodistance studies, and traits that are more mechanically affected, for use in past activity reconstruction.Show less

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Non-Metric Traits. An Assessment of Cranial and Post-Cranial Non-Metric Traits in the Skeletal Assemblage from the 17th-19th Century Churchyard of Middenbeemster, the Netherlands.