Biology subjects

Gallois, S.

Publications and source records attributed to Gallois, S..

3 recordsLinked to original sources

bioRxiv2022

High conservation of the dental plaque microbiome community across populations with differing subsistence strategies and levels of market integration

Industrialization - including urbanization, participation in the global food chain, and consumption of heavily processed foods - is thought to drive substantial shifts in the human microbiome. While diet strongly influences stool microbiome composition, the influence of diet on the oral microbiome, and particularly dental plaque, is largely speculative. Here we investigated whether dental plaque microbial communities are distinctly different across populations with dissimilar subsistence strategies and degree of industrialized market integration. Using a metagenomic approach, we compared the dental plaque microbiomes of Baka foragers and Nzime subsistence agriculturalists in Cameroon (n = 46) with the dental plaque and calculus microbiomes of highly industrialized populations in North America and Europe. We found that differences in microbial taxonomic composition between populations were minimal, with high conservation of abundant microbial taxa and no significant differences in microbial diversity related to dietary practices. Instead, we find that the major source of variation in dental plaque microbial species composition is related to tooth location and oxygen availability, and may be influenced by toothbrushing or other dental hygiene measures. Our results support that dental plaque, in contrast to the stool microbiome, maintains an inherent stability against ecological perturbations in the oral environment.

microbiology↗

bioRxiv2020

Methodological priorities in assessing wild edible plant knowledge and use: a case study among the Baka in Cameroon.

Freelisting and dietary recalls are frequently used methods in ethnobotany to assess wild edible plant (WEP) knowledge and use. Though these ex-situ interviewing methods are practical to perform and may yield large datasets in a short time, they are known to be limited by the informants memory and cognitive bias. Alternatively, the much more laborious walk-in-the-woods method may be used, in which informants point out edible plants in-situ. Few studies, however, examine quantitatively how these different methods influence results. In this study, we assessed how these methods capture the diversity of wild edible plant knowledge and use among the Baka, a group of forager-horticulturalists from southeastern Cameroon. We show that within a single population, and when data on consumption frequency are collected simultaneously, the walk-in-the-woods method results in more detailed information of WEP knowledge and use than do freelisting or dietary recalls. Our in-situ method yielded 91 species of WEP, much more than the ex-situ methods of freelisting (34 spp.) and dietary recalls (12 spp.). Our results imply that previous studies based only on ex situ surveys may have underestimated the importance of WEP for local communities. We propose that future studies on WEP knowledge and use frequency should rely on mixed methods, taking an in-situ method as the starting point of their approach.

plant biology↗

bioRxiv2019

The Life History of Human Foraging: Cross-Cultural and Individual Variation

Human adaptation depends upon the integration of slow life history, complex production skills, and extensive sociality. Refining and testing models of the evolution of human life history and cultural learning will benefit from increasingly accurate measurement of knowledge, skills, and rates of production with age. We pursue this goal by inferring individual hunters of hunting skill gain and loss from approximately 23,000 hunting records generated by more than 1,800 individuals at 40 locations. The model provides an improved picture of ages of peak productivity as well as variation within and among ages. The data reveal an average age of peak productivity between 30 and 35 years of age, though high skill is maintained throughout much of adulthood. In addition, there is substantial variation both among individuals and sites. Within study sites, variation among individuals depends more upon heterogeneity in rates of decline than in rates of increase. This analysis sharpens questions about the co-evolution of human life history and cultural adaptation. It also demonstrates new statistical algorithms and models that expand the potential inferences drawn from detailed quantitative data collected in the field.

animal behavior and cognition↗