Long‐term persistence of wildlife populations in a pastoral area

Facilitating coexistence between people and wildlife is a major conservation challenge in East Africa. Some conservation models aim to balance the needs of people and wildlife, but the effectiveness of these models is rarely assessed. Using a case‐study approach, we assessed the ecological performance of a pastoral area in northern Tanzania (Manyara Ranch) and established a long‐term wildlife population monitoring program (carried out intermittently from 2003 to 2008 and regularly from 2011 to 2019) embedded in a distance sampling framework. By comparing density estimates of the road transect‐based long‐term monitoring to estimates derived from systematically distributed transects, we found that the bias associated with nonrandom placement of transects was nonsignificant. Overall, cattle and sheep and goat reached the greatest densities and several wildlife species occurred at densities similar (zebra, wildebeest, waterbuck, Kirk's dik‐dik) or possibly even greater (giraffe, eland, lesser kudu, Grant's gazelle, Thomson's gazelle) than in adjacent national parks in the same ecosystem. Generalized linear mixed models suggested that most wildlife species (8 out of 14) reached greatest densities during the dry season, that wildlife population densities either remained constant or increased over the 17‐year period, and that herbivorous livestock species remained constant, while domestic dog population decreased over time. Cross‐species correlations did not provide evidence for interference competition between grazing or mixed livestock species and wildlife species but indicate possible negative relationships between domestic dog and warthog populations. Overall, wildlife and livestock populations in Manyara Ranch appear to coexist over the 17‐year span. Most likely, this is facilitated by existing connectivity to adjacent protected areas, effective anti‐poaching efforts, spatio‐temporal grazing restrictions, favorable environmental conditions of the ranch, and spatial heterogeneity of surface water and habitats. This long‐term case study illustrates the potential of rangelands to simultaneously support wildlife conservation and human livelihood goals if livestock grazing is restricted in space, time, and numbers.     

High School Gay–Straight Alliances (GSAs) and Young Adult Well-Being: An Examination of GSA Presence,Participation, and Perceived Effectiveness

Gay–Straight Alliances (GSAs) are student-led, school-based clubs that aim to provide a safe environment in the school context for lesbian, gay, bisexual, and transgender (LGBT) students, as well as their straight allies. The present study examines the potential for GSAs to support positive youth development and to reduce associations among LGBT-specific school victimization and negative young adult well-being. The sample includes 245 LGBT young adults, ages 21–25, who retrospectively reported on the presence of a GSA in their high school, their participation in their school's GSA, and their perceptions of whether or not their GSA was effective in improving school safety. Findings revealed that the presence of a GSA, participation in a GSA, and perceived GSA effectiveness in promoting school safety were differentially associated with young adult well-being and, in some cases, buffered the negative association between LGBT-specific school victimization and well-being. Implications for future research and schools are discussed.     

Potential Sequential Exposures to 2-Butoxyethanol After Use of a Hard-Surface Cleaner

Professional workers and consumers frequently use hard-surface cleaning products and these products may contain glycol ethers (GEs), such as 2-Butoxyethanol (2-BE). Governmental agencies have set exposure limits for some chemicals used in cleaning products and these exposure limits have been used as guides to protect human health. The study objectives were to determine realistic inhalation exposures for professional workers performing multiple, sequential cleaning tasks and compare the exposures to the acute reference exposure level (REL), which California established for 2-BE. The ConsExpo model was acceptable for evaluating exposure based on a comparison of its predictions to experimentally measured 2-BE vapor concentrations from hard-surface cleaning. The typical worker exposure was predicted for a cleaning scenario consisting of three bathrooms and three kitchens (or three bedrooms) in a 1-h period. This exposure scenario would not be expected to result in significant health consequences because the predicted exposure was much lower than the REL. The predicted chronic and aggregate exposures were also acceptable. This analysis identified two important variables that affect inhalation exposure: cleaners should be used with adequate ventilation and wet wiping towels should be properly disposed so that they are not a source of continuing exposure.     

PGC-1 Coactivators Regulate MITF and the Tanning Response

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Highlights? PGC-1 induces pigment formation in melanocytes ? PGC-1s activate expression of MITF ? α-MSH induces PGC-1s, which are required for induction of melanogenic genes ? eQTLs in human PGC-1β are associated with tanning ability and melanoma protection     

Visual Cues Given by Humans Are Not Sufficient for Asian Elephants (Elephas maximus) to Find Hidden Food

Recent research suggests that domesticated species – due to artificial selection by humans for specific, preferred behavioral traits – are better than wild animals at responding to visual cues given by humans about the location of hidden food. \Although this seems to be supported by studies on a range of domesticated (including dogs, goats and horses) and wild (including wolves and chimpanzees) animals, there is also evidence that exposure to humans positively influences the ability of both wild and domesticated animals to follow these same cues. Here, we test the performance of Asian elephants (Elephas maximus) on an object choice task that provides them with visual-only cues given by humans about the location of hidden food. Captive elephants are interesting candidates for investigating how both domestication and human exposure may impact cue-following as they represent a non-domesticated species with almost constant human interaction. As a group, the elephants (n = 7) in our study were unable to follow pointing, body orientation or a combination of both as honest signals of food location. They were, however, able to follow vocal commands with which they were already familiar in a novel context, suggesting the elephants are able to follow cues if they are sufficiently salient. Although the elephants’ inability to follow the visual cues provides partial support for the domestication hypothesis, an alternative explanation is that elephants may rely more heavily on other sensory modalities, specifically olfaction and audition. Further research will be needed to rule out this alternative explanation.