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Thiebaut, A.

Publications and source records attributed to Thiebaut, A..

2 recordsLinked to original sources

DeMoDa: A global open access database for comparative research in human dental morphological variation

Human dental morphology is diverse and varies both within and between populations worldwide. Common variants include different numbers of cusps and roots, as well as different configurations in the fissures, ridges, and grooves on tooth crowns. Because teeth preserve well in taphonomic contexts and retain strong genetic signatures in their morphology, researchers across disciplines use dental form for research ranging from population affinity identification in forensic cases to the reconstruction of population history in archaeological and paleontological studies, and to explore the genetic underpinnings of dental development. However, these analyses are limited, as no publicly available comprehensive database of human dental morphological variation currently exists. Data are typically shared only within professional networks, excluding scientists outside those circles. Information is dispersed across repositories and the supplementary materials that accompany peer-reviewed publications, creating a fragmented and difficult-to-navigate data landscape. Although numberous dental anthropologists devoted their careers to collecting extensive datasets from thousands of individuals worldwide, their data have not yet been published in raw form nor made compatible. Here, we introduce the Dental Morphological Database (DeMoDa), an open access repository comprising 246 dental traits for 17,308 individuals across 32 major geographic regions worldwide spanning the past several thousand years. These data are from the legacy datasets of Turner, Hanihara, Scott, and Irish. Because these researchers used different scoring systems, we developed a scoring system with two steps that enables the three most-common scoring systems to be combined. We provide two versions of the data that correspond to these two steps: one with more nuanced trait scores at the cost of a smaller sample size, and another with less nuanced trait scores but broader sample coverage. We discuss the implications of publishing these legacy data and outline our decision-making process that guided their release in accordance with both the FAIR and CARE principles of open science.

evolutionary biology↗

Functional constraints on insect immune system components govern their evolutionary trajectories

The role of constraints in shaping evolutionary outcomes is often investigated in the contexts of developmental biology and population genetics, in terms of the capacity to generate new variants as well as how selection either limits or promotes consequent phenotypic change. Comparative genomics also recognises the role of constraints, in terms of shaping the evolution of gene and genome architectures, sequence evolutionary rates, and gene gains and losses, as well as on molecular phenotypes. Characterising patterns of genomic change where putative functions and interactions of system components are relatively well-described offers opportunities to explore whether genes with similar or analogous roles exhibit similar evolutionary trajectories, possibly governed by common constraints. Using insect innate immunity as our study system, we hypothesise that quantitative characterisation of gene evolutionary histories can define distinct dynamics associated with different functional roles. We develop metrics that quantify gene evolutionary histories, employ these to characterise evolutionary features of immune gene repertoires, and explore relationships between gene family evolutionary profiles and their roles in immunity to understand how different constraints may relate to distinct dynamics. We identified three main axes of evolutionary trajectories characterised by gene duplication and synteny, maintenance/stability and sequence conservation, and loss and sequence divergence, highlighting similar and contrasting patterns across these axes amongst subsets of immune genes. Our results indicate that where and how genes participate in immune responses limit the range of possible evolutionary scenarios they exhibit. Comparative genomics approaches therefore offer opportunities to characterise how functional constraints on different components of biological systems govern their evolutionary trajectories.

evolutionary biology↗