Original scientific paper
Dental fluctuating asymmetry in Portugal: developmental instability in Valença and the Coimbra reference sample
Luís Miguel Marado
orcid.org/0000-0003-0116-9433
; Unit of Archaeology, University of Minho, Braga, Portugal
Abstract
Fluctuating asymmetry (FA) is commonly used to estimate developmental instability (DI), the organism’s response to ontogenic disturbance. This work aims to (1) select nonmetric dental traits for FA testing, according to representativeness and comparability; (2) test DI differences between Valença and Coimbra, two Portuguese samples. Valença (VLN) is a 17th-19th century sample of 31 individuals from a Fortress in the northern border of Portugal. Coimbra (COI) is a 19th/20th century sample of 600 individuals from the Coimbra identified collections, compiled as a Portuguese reference sample. Twenty-nine dental nonmetric traits were scored for Valença and Coimbra. Correlations of FA results between traits were computed. After removal of problematic traits, percentages of FA, Comparable FA (CFA) (removing cases with bilateral trait absence) and Variation FA (VFA) (removing cases with bilateral lack of trait expression) were calculated. FA percentages were compared using Mann-Whitney U rank-sum test and z-ratio (difference of independent proportions test). Samples do not present significant difference in mean individual percentage for FA, CFA, or VFA. Differences in asymmetry proportion were also not statistically distinct for CFA. Yet, proportions differed significantly for FA (VLN: 16.9%, COI: 10.7%; z=-2.34, p=0.0193) and VFA (VLN: 58.6%, COI: 39.3%; z=-2.133, p=0.0346). FA levels suggest Valença suffered from greater levels of DI than Coimbra. Despite of the low socioeconomic status of both samples, Valença individuals possibly had lesser access to adequate nutrition and healthcare due to Valença’s rural context and peripheral location.
Keywords
bioarchaeology; nutrition and healthcare during development; nonmetric dental traits; modern and contemporary Portugal; peripheral town
Hrčak ID:
191604
URI
Publication date:
28.12.2017.
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