Gut microbiota can have important effects on host health, but explanatory factors and pathways that determine gut microbial composition can differ among host lineages. In mammals, host phylogeny is one of the main drivers of gut microbiota, a result of vertical transfer of microbiota during birth. In birds, it is less clear what the drivers might be, but both phylogeny and environmental factors may play a role.
View Article and Find Full Text PDFThe behavioural rhythms of organisms are thought to be under strong selection, influenced by the rhythmicity of the environment. Such behavioural rhythms are well studied in isolated individuals under laboratory conditions, but free-living individuals have to temporally synchronize their activities with those of others, including potential mates, competitors, prey and predators. Individuals can temporally segregate their daily activities (for example, prey avoiding predators, subordinates avoiding dominants) or synchronize their activities (for example, group foraging, communal defence, pairs reproducing or caring for offspring).
View Article and Find Full Text PDFTotal mercury concentrations ([THg]), δN and δC values were determined in muscle of 693 Pacific halibut caught in International Pacific Halibut Commission setline surveys in Alaska (2002-2011). Project goals were to evaluate whether 1) δN and δC varied with region, age, sex and length of halibut, and 2) muscle [THg] varied with δN and δC (feeding ecology) while accounting for sex, length, and region. Variation in [THg] was explained, in part, by halibut feeding ecology as [THg] increased with trophic position (increasing δN).
View Article and Find Full Text PDFBackground: Geolocators are useful for tracking movements of long-distance migrants, but potential negative effects on birds have not been well studied. We tested for effects of geolocators (0.8-2.
View Article and Find Full Text PDFConcentrations of total mercury ([THg]) and selenium ([TSe]) were measured in several tissue compartments in Steller sea lion (Eumetopias jubatus) pups; in addition we determined specific compartment and body burdens of THg. Compartmental and body burdens were calculated by multiplying specific compartment fresh weight by the [THg] (summing compartment burdens equals body burden). In all 6 pup tissue sets (1) highest [THg] was in hair, (2) lowest [THg] was in bone, and (3) pelt, muscle and liver burdens contributed the top three highest percentages of THg body burden.
View Article and Find Full Text PDFToxicol Rep
October 2014
Seafood is a valuable source of nutrients important for fetal development. However, seafood consumption is the main route of exposure to monomethyl mercury (MeHg) for humans. MeHg is highly bioavailable and potentially adversely affects fetal neurodevelopment.
View Article and Find Full Text PDFSeafood provides essential polyunsaturated fatty acids (PUFA) and other nutrients to pregnant women and their fetus(es) while a diet rich in finfish can be a major pathway of monomethyl mercury (MeHg) exposure. We measured total mercury concentration ([THg]) in hair samples provided by 75 women in Baja California Sur (BCS) to assess its relationship with age, parity, tobacco smoke exposure, and diet based on survey methodologies. Generalized linear models (GLM) were used to explain the possible association of the different variables with [THg] in hair.
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