17 research outputs found
Neighborhood environment, social cohesion, and epigenetic aging
Living in adverse neighborhood environments has been linked to risk of aging-related diseases and mortality; however, the biological mechanisms explaining this observation remain poorly understood. DNA methylation (DNAm), a proposed mechanism and biomarker of biological aging responsive to environmental stressors, offers promising insight into potential molecular pathways. We examined associations between three neighborhood social environment measures (poverty, quality, and social cohesion) and three epigenetic clocks (Horvath, Hannum, and PhenoAge) using data from the Detroit Neighborhood Health Study (n=158). Using linear regression models, we evaluated associations in the total sample and stratified by sex and social cohesion. Neighborhood quality was associated with accelerated DNAm aging for Horvath age acceleration (β = 1.8; 95% CI: 0.4, 3.1), Hannum age acceleration (β = 1.7; 95% CI: 0.4, 3.0), and PhenoAge acceleration (0 = 2.1; 95% CI: 0.4, 3.8). In models stratified on social cohesion, associations of neighborhood poverty and quality with accelerated DNAm aging remained elevated for residents living in neighborhoods with lower social cohesion, but were null for those living in neighborhoods with higher social cohesion. Our study suggests that living in adverse neighborhood environments can speed up epigenetic aging, while positive neighborhood attributes may buffer effects
Phylogenetic diversity and the conservation biogeography of African primates
Aim Phylogenetics has an important role in conservation biogeography.
However, there are few data on the phylogenetic diversity of African primates.
The phylogenetic diversity (PD) of a species is a measure of its taxonomic
distinctness and can be estimated by looking at the phylogenetic relationships
among taxa. Species-specific metrics on PD can then be used to determine
conservation priorities at various biogeographical scales. We used PD metrics to
rank 55 African primate species according to their conservation priorities at the
country level and within six African biogeographical regions. We also addressed
the following question: are there differences in conservation rankings between the
IUCN Red List and our PD metrics?
Location Africa.
Methods We created a consensus phylogeny for all African primate clades based
on genetic studies. Analyses of species distributions were determined using
presence/absence scores at two levels: country and biogeographical region.
A node-based method that standardizes for widespread taxa and endemicity was
used to calculate PD indices. Hierarchical cluster analysis was used to convert one
of the standardized, phylogenetic indices into three clusters that could be ranked
and compared with the main IUCN conservation rankings of endangered,
vulnerable, and lower risk.
Results At the country and region levels, the top-priority species in terms of PD are
Pan paniscus, Macaca sylvanus, Arctocebus calabarensis, Gorilla beringei, Arctocebus
aureus, Allenopithecus nigroviridis, Gorilla gorilla, Procolobus verus, Cercopithecus
solatus, Cercocebus galeritus, Colobus angolensis, Theropithecus gelada, Galagoides
zanzibaricus, Galagoides granti, and Procolobus (Piliocolobus) badius. Geographic
rankings were highest for the Democratic Republic of the Congo (country level) and
Central Africa (region level). Although there were no overall differences between
IUCN conservation ranks and the PD rankings, there were significant differences
between the two systems for vulnerable and endangered primate taxa.
Main conclusions There are few ecological and behavioural data on populations
of some of the African primates that represent the highest levels of phylogenetic
diversity. Studies of primate taxa with high PD rankings should focus on
identifying sites suitable for intensive studies of population densities, feeding
ecology, and reproductive behaviour. We suggest that PD metrics can serve as an
important, complementary data set in the IUCN ranking system for primates