Individual Dietary Specialization in a Generalist Bee Varies across Populations but Has No Effect on the Richness of Associated Microbial Communities.

AbstractDespite the increasingly documented occurrence of individual specialization, the relationship between individual consumer interactions and diet-related microbial communities in wild populations is still unclear. Using data from nests of Ceratina australensis from three different wild bee populations, we combine metabarcoding and network approaches to explore the existence of individual variation in resource use within and across populations and whether dietary specialization affects the richness of pollen-associated microbes. We reveal the existence of marked dietary specialization. In the most specialized population, we also show that individuals' diet breadth was positively related to the richness of fungi but not bacteria. Overall, individual specialization appeared to have a weak or negligible effect on the microbial richness of nests, suggesting that different mechanisms beyond environmental transmission may be at play regarding microbial acquisition in wild bees.

Pollinator interaction flexibility across scales affects patch colonization and occupancy.

Global change alters ecological communities and may disrupt ecological interactions and the provision of ecosystem functions. As ecological communities respond to global change, species may either go locally extinct or form novel interactions. To date, few studies have assessed how flexible species are in their interaction patterns, mainly due to the scarcity of data spanning long time series. Using a ten-year species-level dataset on the assembly of mutualistic networks from the Central Valley in California, we test whether interaction flexibility affects pollinators' colonization and persistence and their resulting habitat occupancy in a highly modified landscape. We propose three metrics of interaction flexibility associated with different scales of organization within ecological communities and explore which species' traits affect them. Our results provide empirical evidence linking species' ability to colonize habitat patches across a landscape to the role they play in networks. Phenological breadth and body size had contrasting effects on interaction flexibility. We demonstrate the relationship between mutualistic networks and species' ability to colonize and persist in the landscape, suggesting interaction flexibility as a potential mechanism for communities to maintain ecosystem function despite changes in community composition.

Structural vulnerability of hospitals, cemeteries, and crematoriums of the city of São Paulo to COVID-19 / Vulnerabilidade estrutural dos hospitais e cemitérios e crematórios da cidade de São Paulo à COVID-19

This is the first report by the COVID19 Observatory - Group: Contagion Networks analyzing mortality data from the city of São Paulo. In this report, we integrated mortality data for the city of São Paulo between 04/02/2020 and 04/28/2020, with information on the flow of victims between hospitals and cemeteries/crematoriums. We included in our analyzes both confirmed and suspected deaths from COVID-19. The main objectives of this report were: (1) to describe the structure of the flow of victims between locations and (2) to suggest changes in the current flow based on geographical distances in order to avoid a potential overload of the mortuary system. We suggest that the city of São Paulo should plan for a potential overload of the mortuary system (that is, the number of burials), based on the presented results. Thus, our results reinforce the need to adopt specific planning for the management of the extraordinary number of victims of this pandemic. Our predictions are based on the structural analysis of the COVID-19 victim flow network, which shows several hotspots with high vulnerability to system overload. These hotspots concentrate with either the greatest number of deaths (hospital) or of burials (cemetery or crematorium), and therefore have high potential to become overwhelmed by receiving many bodies due to the increase in victims of the pandemic. We recommend special attention to be given to localities on the east side of São Paulo, which has both the most vulnerable hospitals in the city, and also houses cemeteries and crematoriums that have a central role in the network and / or are vulnerable. Based on our optimization analysis, we suggest logistical changes in the current flow of bodies from hospitals to cemeteries/crematoriums so as not to overload the funeral system and minimize transportation costs. In this sense, our results are potentially useful for improving the operational planning of the Municipality of São Paulo, ratifying or rectifying actions underway at the municipal level.

Este é o primeiro relatório do Observatório COVID19 - Grupo: Redes de Contágio analisando os dados de óbitos da cidade de São Paulo. Neste relatório, integramos os dados de óbitos da cidade de São Paulo entre os dias 02/04/2020 e 28/04/2020 com informações sobre o fluxo de vítimas entre os hospitais e os cemitérios e crematórios da cidade de São Paulo. Incluímos em nossas análises óbitos confirmados e óbitos suspeitos de COVID-19. Os principais objetivos deste relatório são: (1) descrever a estrutura do fluxo de vítimas entre localidades e (2) sugerir mudanças no fluxo com base em distâncias geográficas de maneira a evitar uma potencial sobrecarga do sistema funerário. Sugere-se à prefeitura da cidade de São Paulo que seja realizado um planejamento para uma potencial sobrecarga do sistema funerário (isto é, número de sepultamentos) da cidade de São Paulo com base nos resultados apresentados. Desta forma, nossos resultados reforçam a necessidade de ser adotado planejamento específico para a gestão dos casos extraordinários visualizados no contexto da pandemia. Esta previsão está baseada na análise estrutural da rede de fluxos de vítimas da COVID-19, que indica a concentração de vários locais com alta vulnerabilidade à sobrecarga do sistema. Tais locais concentram a maior quantidade de óbitos (hospitais) ou a maior concentração de sepultamentos (cemitérios ou crematórios) e tem portanto alto potencial de tornarem-se sobrecarregados por receberem muitos corpos devido ao aumento de vítimas da pandemia. Recomenda-se especial atenção à localidades da zona leste de São Paulo, que apresenta os hospitais mais vulneráveis da cidade e abriga cemitérios e crematórios que possuem papel central na rede e/ou encontram-se vulneráveis. Com base em nossa análise de otimização, sugerimos mudanças logísticas no atual fluxo de corpos de hospitais para cemitérios/crematórios de modo a não sobrecarregar o sistema funerário e minimizar os custos de transporte. Neste sentido, nossos resultados são potencialmente úteis ao aperfeiçoamento do planejamento operacional da Prefeitura Municipal de São Paulo, ratificando ou retificando ações em curso no âmbito municipal.

Full-annual demography and seasonal cycles in a resident vertebrate.

Wildlife demography is typically studied at a single point in time within a year when species, often during the reproductive season, are more active and therefore easier to find. However, this provides only a low-resolution glimpse into demographic temporal patterns over time and may hamper a more complete understanding of the population dynamics of a species over the full annual cycle. The full annual cycle is often influenced by environmental seasonality, which induces a cyclic behavior in many species. However, cycles have rarely been explicitly included in models for demographic parameters, and most information on full annual cycle demography is restricted to migratory species. Here we used a high-resolution capture-recapture study of a resident tropical lizard to assess the full intra-annual demography and within-year periodicity in survival, temporary emigration and recapture probabilities. We found important variation over the annual cycle and up to 92% of the total monthly variation explained by cycles. Fine-scale demographic studies and assessments on the importance of cycles within parameters may be a powerful way to achieve a better understanding of population persistence over time.