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Sex- and age-based social structures have been well documented in animals with visible aggregations. However, very little is known about the social structures of snakes. This is most likely because snakes are often considered non-social animals and are particularly difficult to observe in the wild. Here, we show that wild Butler's Gartersnakes have an age and sex assorted social structure similar to more commonly studied social animals. To demonstrate this, we use data from a 12-year capture-mark-recapture study to identify social interactions using social network analyses. We find that the social structures of Butler's Gartersnakes comprise sex- and age-assorted intra-species communities with older females often central and age segregation partially due to patterns of study site use. In addition, we find that females tended to increase in sociability as they aged while the opposite occurred in males. We also present evidence that social interaction may provide fitness benefits, where snakes that were part of a social network were more likely to have improved body condition. We demonstrate that conventional capture data can reveal valuable information on social structures in cryptic species. This is particularly valuable as research has consistently demonstrated that understanding social structure is important for conservation efforts. Additionally, research on the social patterns of animals without obvious social groups provides valuable insight into the evolution of group living.

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The problem of residential age segregation has been relatively under-studied, since spatial separation of older and younger people tends to be normalized. Prior literature demonstrates that age segregated environments may be socially isolating, especially for older adults, which may have detrimental impacts on their physical and mental health. While there are some studies on residential age segregation in Western contexts, there is scarce literature on age segregation in Asian cities. This mixed methods study examines changing patterns of residential age segregation in Hong Kong, through analyzing a combination of secondary census data and qualitative, in-depth interview data. The findings reveal that the extent of age segregation has remained consistently low from 2006 to 2016, although age segregation appears to be more pronounced between young adults in their early 20s and older adults above 65. Furthermore, in-depth interviews with 26 older people reveal that older people perceive themselves as being socially separated from younger people, especially older people who remain in ageing housing estates in urban districts. The findings add to the growing international literature on generational divides in spatial inequalities, while highlighting the influence of local housing policies on age segregation. The paper concludes by considering the policy implications of the findings, and the practical interventions that might contribute to reducing social isolation experienced by older people.

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Age segregation adversely impacts health and wellbeing. Prior studies, although limited, report increasing age segregation of the US. However, these studies are dated, do not comprehensively examine the spatiotemporal patterns and the correlates of intergenerational segregation, or suffer from methodological limitations. To address these gaps, we assess the spatiotemporal patterns of age segregation between 1990 and 2010 using census-tract data to compute the dissimilarity index (D) at the national, state, and county levels. Results contradict previous findings, providing robust evidence of decreasing age segregation for most parts of the country and across geographical levels. We also examine factors explaining adult-older adult segregation across counties between 1990 and 2010. Higher levels of rurality indicated lower levels of adult-older adult segregation, but this association diminished over time. Percent of older adults and percent of population in group quarters were inversely related to adult-older adult segregation, contrary to results from previous decades.

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The degree of spatial autocorrelation in population fluctuations increases with dispersal and geographical covariation in the environment, and decreases with strength of density dependence. Because the effects of these processes can vary throughout an individual's lifespan, we studied how spatial autocorrelation in abundance changed with age in three marine fish species in the Barents Sea. We found large interspecific differences in age-dependent patterns of spatial autocorrelation in density. Spatial autocorrelation increased with age in cod, the reverse trend was found in beaked redfish, while it remained constant among age classes in haddock. We also accounted for the average effect of local cohort dynamics, i.e. the expected local density of an age class given last year's local density of the cohort, with the goal of disentangling spatial autocorrelation patterns acting on an age class from those formed during younger age classes and being carried over. We found that the spatial autocorrelation pattern of older age classes became increasingly determined by the distribution of the cohort during the previous year. Lastly, we found high degrees of autocorrelation over long distances for the three species, suggesting the presence of far-reaching autocorrelating processes on these populations. We discuss how differences in the species' life history strategies could cause the observed differences in age-specific variation in spatial autocorrelation. As spatial autocorrelation can differ among age classes, our study indicates that fluctuations in age structure can influence the spatio-temporal variation in abundance of marine fish populations.

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Hadrosaurid (duck-billed) dinosaur bonebeds are exceedingly prevalent in upper Cretaceous (Campanian-Maastrichtian) strata from the Midwest of North America (especially Alberta, Canada, and Montana, U.S.A) but are less frequently documented from more northern regions. The Wapiti Formation (Campanian-Maastrichtian) of northwestern Alberta is a largely untapped resource of terrestrial palaeontological information missing from southern Alberta due to the deposition of the marine Bearpaw Formation. In 2018, the Boreal Alberta Dinosaur Project rediscovered the Spring Creek Bonebed, which had been lost since 2002, along the northern bank of the Wapiti River, southwest of Grande Prairie. Earlier excavations and observations of the Spring Creek Bonebed suggested that the site yielded young hadrosaurines. Continued work in 2018 and 2019 recovered ~300 specimens that included a minimum of eight individuals, based on the number of right humeri. The morphology of several recovered cranial elements unequivocally supports lambeosaurine affinities, making the Spring Creek sample the first documented occurrence of lambeosaurines in the Wapiti Formation. The overall size range and histology of the bones found at the site indicate that these animals were uniformly late juveniles, suggesting that age segregation was a life history strategy among hadrosaurids. Given the considerable size attained by the Spring Creek lambeosaurines, they were probably segregated from the breeding population during nesting or caring for young, rather than due to different diet and locomotory requirements. Dynamic aspects of life history, such as age segregation, may well have contributed to the highly diverse and cosmopolitan nature of Late Cretaceous hadrosaurids.

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OBJECTIVES: This article compares responses to coronavirus control in Australia, the United Kingdom, and the United States, 3 countries in which public ageism erupted over the social and economic costs of protecting older adults from Covid-19. METHODS: Thirty-five (35) newspapers, media websites, and current affairs magazines were sourced for the study: 8 for Australia, 12 for the United Kingdom, and 15 for the United States. Searches were conducted daily from April to June 2020, using key words to identify age-related themes on pandemic control. RESULTS: Despite divergent policies in the 3 countries, ageism took similar forms. Public responses to lockdowns and other measures cast older adults as a problem to be ignored or solved through segregation. Name-calling, blame, and "so-be-it" reactions toward age vulnerability were commonplace. Policies banning visits to aged care homes angered many relatives and older adults. Indefinite isolation for older adults was widely accepted, especially as a vehicle to end public lockdowns and economic crises. DISCUSSION: Older adults have and will continue to bear the brunt of Covid-19 in terms of social burdens and body counts as the pandemic continues to affect people around the globe. The rhetoric of disposability underscores age discrimination on a broader scale, with blame toward an age cohort considered to have lived past its usefulness for society and to have enriched itself at the expense of future generations.

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BACKGROUND: Piglet diarrhoea is considered a worldwide problem resulting in animal welfare problems and financial losses for pig farmers. Porcine rotavirus and the coccidian parasite Cystoisospora suis (C. suis) are considered two important pathogens associated with diarrhoea in piglets during the suckling and early post weaning periods. To obtain an overview on the prevalence of porcine rotavirus and C. suis in piglet producing herds with solid floors and age segregated rearing, faecal sampling of 791 litters in 81 farms was performed. RESULTS: For porcine rotavirus, faecal samples were analysed using a sandwich ELISA. The overall prevalence of rotavirus in the examined herds was 11.4 ± 17.7% at 2 weeks, 56.8 ± 30.7% at 4 weeks and 71.1 ± 29.1% at 6 weeks of age and the accumulated prevalence was 49, 97 and 100%. To detect C. suis, faecal samples were analysed using sedimentation. The overall prevalence of C. suis in the examined herds was 11.9 ± 15.1% at 2 weeks of age, 10.7 ± 16.7% at 4 weeks and 8.7 ± 15.3% at 6 weeks of age and the accumulated prevalence was 56, 76 and 85%. The number of empty days between farrowing batches did influence the shedding of rotavirus at 2 weeks of age but not later. Regarding C. suis, no difference in prevalence was correlated to the number of days between consecutive farrowing batches. CONCLUSIONS: Our study confirmed that rotavirus should be regarded as an ubiquitous virus that can be expected to be present in almost every pig herd in Sweden. The study also demonstrated that the number of infected litters increased from birth to 6 weeks of age. Secondly, it showed that C. suis frequently occurred in pig herds and that the number of infected litters was rather stable from two to 6 weeks of age. Consequently, both rotavirus and C. suis may play a role in intestinal disturbances in piglets during the suckling and post weaning periods despite age segregated rearing, at least in systems with solid floors. However, as this study was carried out in herds without reported problems with diarrhoea or poor weight gain, the role of these pathogens should not be overestimated.

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This article reviews cultural differences in the extent of segregation of children from community life and their integration with people of differing ages, focusing especially on children's engagement with older children or similar-age children. We highlight cultural differences in children's everyday companionship with older children and with peers by discussing a study using naturalistic observations of young children's days in four cultural communities. Young children were more often involved with older children (who were often related to them) among the Efe of the Ituri Forest of the Democratic Republic of Congo and in the Guatemalan Mayan town of San Pedro, whereas middle-class European American children from two regions in the United States were more frequently involved with children of similar ages (who were often unrelated to them). The mainstream research focus on similar-age (unrelated) peer involvements, often regarded as the "norm," needs to be broadened to consider the various patterns of children's social engagements worldwide, which often involve integration of children in broader communities, engaging with adults and children of all ages.

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The growing number of older prisoners in state and federal prisons has fostered an important discussion in literature regarding the potential benefits of age-segregated living arrangements for older inmates. This article begins with a brief review of the reasons for America's aging prison population. Thereafter, it uses a multidisciplinary literature review to clarify a 4-point rationale for age-segregated prisons: (a) cost savings via centralized health care for older prisoners; (b) the reduction of civil liabilities for correctional systems that centralize disability services as per requirements of the Americans with Disabilities Act of 1990; (c) the advancement of prisoner safety for older inmates; and (d) the promotion of rehabilitation by advancing treatment opportunities with a group that is most likely to desist from future criminal activity (in part) due to age-related desistance from crime. Conclusions focus on age segregation within the historical context of segregation in prison based on sociodemographic characteristics.