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Understanding how bees use resources at a landscape scale is essential for developing meaningful management plans that sustain populations and the pollination services they provide. Bumblebees are important pollinators for many wild and cultivated plants, and have experienced steep population declines worldwide. Bee foraging behavior can be influenced by resource availability and bees' lifecycle stage. To better understand these relationships, we studied the habitat selection of Bombus pauloensis by tracking 17 queen bumblebees with radio telemetry in blueberry fields in Entre Ríos province, Argentina. To evaluate land use and floral resources used by bumblebees, we tracked bees before and after nest establishment and estimated home ranges using minimum convex polygons and kernel density methods. We also classified the pollen on their bodies to identify the floral resources they used from the floral species available at that time. We characterized land use for each bee as the relative proportion of GPS points inside of each land use. Bumblebees differed markedly in their movement behavior in relation to pre and post nest establishment. Bees moved over larger areas, and mostly within blueberry fields, before nest establishment. In contrast, after establishing the nest, the bees preferred the edges near forest plantations and they changed the nutritional resources to prefer wild floral species. Our study is the first to track queen bumblebee movements in an agricultural setting and relate movement changes across time and space with pollen resource availability. This study provides insight into the way bumblebee queens use different habitat elements at crucial periods in their lifecycle, showing the importance of mass flowering crops like blueberry in the first stages of queen's lifecycle, and how diversified landscapes help support bee populations as their needs changes during different phases of their lifecycle.

Understanding how bees use resources at a landscape scale is essential for developing meaningful management plans that sustain populations and the pollination services they provide. Bumblebees are important pollinators for many wild and cultivated plants, and have experienced steep population declines worldwide. Bee foraging behavior can be influenced by resource availability and bees' lifecycle stage. To better understand these relationships, we studied the habitat selection of Bombus pauloensis by tracking 17 queen bumblebees with radio telemetry in blueberry fields in Entre Ríos province, Argentina. To evaluate land use and floral resources used by bumblebees, we tracked bees before and after nest establishment and estimated home ranges using minimum convex polygons and kernel density methods. We also classified the pollen on their bodies to identify the floral resources they used from the floral species available at that time. We characterized land use for each bee as the relative proportion of GPS points inside of each land use. Bumblebees differed markedly in their movement behavior in relation to pre and post nest establishment. Bees moved over larger areas, and mostly within blueberry fields, before nest establishment. In contrast, after establishing the nest, the bees preferred the edges near forest plantations and they changed the nutritional resources to prefer wild floral species. Our study is the first to track queen bumblebee movements in an agricultural setting and relate movement changes across time and space with pollen resource availability. This study provides insight into the way bumblebee queens use different habitat elements at crucial periods in their lifecycle, showing the importance of mass flowering crops like blueberry in the first stages of queen's lifecycle, and how diversified landscapes help support bee populations as their needs changes during different phases of their lifecycle.

Competition among the sperm of rival males is an important evolutionary phenomenon in many organisms. Yet, despite extensive research on sperm competition in some vertebrate taxa, very little progress has been made on this topic in amphibians. Urodele amphibians (newts and salamanders) are of particular interest to theories of sperm competition because most urodele females-in contrast to other vertebrate females-control the transfer of sperm from the male. Here we present a molecular study of sperm precedence and storage patterns in the rough-skinned newt (Taricha granulosa). First, we used microsatellite markers to show that female newts typically use sperm from 1-3 males under natural and seminatural conditions. Second, we mated experimental females sequentially to two males and collected fertilized eggs in a temporal series. Patterns of paternity were consistent with first-male sperm precedence and complete mixing of sperm within the female. This simple pattern of sperm usage, best described as \"topping off,\" is consistent with the expectation from sexual conflict theory that free female choice before insemination eliminates selective pressures for the evolution of complex patterns of paternity manipulation involving cryptic female choice.

The purpose of this narrative study was to describe how older women of rural Appalachia learned their cultural ways of care and caregiving. Using Situated Learning (Lave & Wenger, 1999; Lave, 2019), Care Focused Feminism (Noddings, 1984, 2002) and Bonding Social Capital (Putnam, 2000) theories, four women of rural Appalachia narrated stories from all stages of life. Findings supported the presence of Legitimate Peripheral Participation (LPP) (Lave & Wenger, 1991) as the primary method of learning as the women learned types of care and caregiving while in participation with family and friends. Types of care analyzed from the narratives were provision, protection, presence, and play. Conclusions drawn from the analysis demonstrated that participants felt more cared for when ‘presence’ was a dominant type of care. This was described as being seen and heard or validated for their authentic self. The research lends itself to Adult Education practitioners by increasing our knowledge in what learners see as valuable care.

The majority of female animals are polyandrous: offspring within a single reproductive event are sired by more than one male. However, we lack a clear understanding of the ultimate causes of polyandry, and of the male reproductive strategies which have evolved in response to selection occurring after insemination. I addressed these issues by conducting three studies of the Ocoee salamander, Desmognathus ocoee (Family Plethodontidae). In the first study, I examined the nature of polyandry. I collected D. ocoee clutches from the field and assessed the number of males siring offspring in each clutch. The data suggest that polyandry is common in D. ocoee, but females do not appear to mate multiply in order to increase clutch size (via female benefits) or from pressure by males (sexual conflict). In the second study, I staged a series of laboratory encounters between a female and two males to investigate the effects of male body size and sperm competition on male reproductive strategies. Paternity data, combined with data from sperm counts (Ch. 3), revealed that large males allocate more sperm per spermatophore, and experience greater insemination and fertilization success, as compared to smaller males. Thus, selection for greater insemination and fertilization success favors the evolution of large male body size in D. ocoee. In the third study, I examined one aspect of male reproductive strategy, sperm allocation. I counted the number of sperm per spermatophore provided to mated and unmated females by males of differing body sizes. I found that males can assess female mating status and vary sperm number to provide more sperm to unmated females. On average, larger males produced spermatophores with more sperm than did smaller males. Thus, variable sperm allocation is an important male strategy resulting from competition for the fertilization of ova (polyandry). Overall, factors other than increased or decreased clutch size have resulted in the evolution of polyandry in D. ocoee. In addition, polyandry clearly has shaped the evolution of both male traits and reproductive strategies in D. ocoee.

Understanding how bees use resources at a landscape scale is essential for developing meaningful management plans that sustain populations and the pollination services they provide. Bumblebees are important pollinators for many wild and cultivated plants, and have experienced steep population declines worldwide. Bee foraging behavior can be influenced by resource availability and the bee’s lifecycle stage. To better understand these relationships, we studied the habitat selection of Bombus atratus by tracking 17 queen bumblebees with radio telemetry in blueberry fields in Entre Ríos province, Argentina. To evaluate land use and floral resources used by bumblebees, we tracked bees before and after nest establishment and estimated home ranges using minimum convex polygons and kernel density methods. We also classify the pollen of their body to determine which botanical resources they use from the floral species available. We characterized land use for each bee as the relative proportion of GPS points inside of each land use. Bumblebees differed markedly in their movement behavior in relation to nest establishment. They moved over larger areas and mostly within blueberry fields before to nest establishment, in contrast to after establishing the nest that they preferred the edges near forest plantations and changed the nutritional resources by wild floral species. Our study is the first to track queen bumblebee movements in an agricultural setting and relate movement change across time and space with pollen resource availability. This study provides insight into the way bumblebee queens use different habitat elements at crucial periods in their lifecycle, showing the importance of mass flowering crops like blueberry in the first stages of queen’s lifecycle and how diversified landscapes help support bee populations as their needs changes during different phases of their lifecycle.

Asthma prevalence has increased in epidemic proportions with urbanization, but growing up on traditional farms offers protection even today1. The asthma-protective effect of farms appears to be associated with rich home dust microbiota2,3, which could be used to model a health-promoting indoor microbiome. Here we show by modeling differences in house dust microbiota composition between farm and non-farm homes of Finnish birth cohorts4 that in children who grow up in non-farm homes, asthma risk decreases as the similarity of their home bacterial microbiota composition to that of farm homes increases. The protective microbiota had a low abundance of Streptococcaceae relative to outdoor-associated bacterial taxa. The protective effect was independent of richness and total bacterial load and was associated with reduced proinflammatory cytokine responses against bacterial cell wall components ex vivo. We were able to reproduce these findings in a study among rural German children2 and showed that children living in German non-farm homes with an indoor microbiota more similar to Finnish farm homes have decreased asthma risk. The indoor dust microbiota composition appears to be a definable, reproducible predictor of asthma risk and a potential modifiable target for asthma prevention.

Hypomyelination, a neurological condition characterized by decreased production of myelin sheets by glial cells, often has no known etiology. Elucidating the genetic causes of hypomyelination provides a better understanding of myelination, as well as means to diagnose, council, and treat patients. Here, we present evidence that YIPPEE LIKE 3 (YPEL3), a gene whose developmental role was previously unknown, is required for central and peripheral glial cell development. We identified a child with a constellation of clinical features including cerebral hypomyelination, abnormal peripheral nerve conduction, hypotonia, areflexia, and hypertrophic peripheral nerves. Exome and genome sequencing revealed a de novo mutation that creates a frameshift in the open reading frame of YPEL3, leading to an early stop codon. We used zebrafish as a model system to validate that YPEL3 mutations are causative of neuropathy. We found that ypel3 is expressed in the zebrafish central and peripheral nervous system. Using CRISPR/Cas9 technology, we created zebrafish mutants carrying a genomic lesion similar to that of the patient. Our analysis revealed that Ypel3 is required for development of oligodendrocyte precursor cells, timely exit of the perineurial glial precursors from the central nervous system (CNS), formation of the perineurium, and Schwann cell maturation. Consistent with these observations, zebrafish ypel3 mutants have metabolomic signatures characteristic of oligodendrocyte and Schwann cell differentiation defects, show decreased levels of Myelin basic protein in the central and peripheral nervous system, and develop defasciculated peripheral nerves. Locomotion defects were observed in adult zebrafish ypel3 mutants. These studies demonstrate that Ypel3 is a novel gene required for perineurial cell development and glial myelination.

NK cell migration and activation are crucial elements of tumor immune surveillance. In mammary carcinomas, the number and function of NK cells is diminished, despite being positively associated with clinical outcome. MicroRNA-155 (miR-155) has been shown to be an important regulator of NK cell activation through its interaction with SHIP-1 downstream of inhibitory NK receptor signaling, but has not been explored in regard to NK cell migration. Here, we explored the migratory potential and function of NK cells in subcutaneous AT3 in mice lacking miR-155. Without tumor, these bic/miR-155-/- mice possess similar numbers of NK cells that exhibit comparable surface levels of cytotoxic receptors as NK cells from wild-type (WT) mice. Isolated miR-155-/- NK cells also exhibit equivalent cytotoxicity towards tumor targets in vitro compared to isolated WT control NK cells, despite overexpression of known miR-155 gene targets. NK cells isolated from miR-155-/- mice exhibit impaired F-actin polymerization and migratory capacity in Boyden-chamber assays in response chemokine (C-C motif) ligand 2 (CCL2). This migratory capacity could be normalized in the presence of SHIP-1 inhibitors. Of note, miR-155-/- mice challenged with mammary carcinomas exhibited heightened tumor burden which correlated with a lower number of tumor-infiltrating NK1.1+ cells. Our results support a novel, physiological role for SHIP-1 in the control of NK cell tumor trafficking, and implicate miR-155 in the regulation of NK cell chemotaxis, in the context of mammary carcinoma. This may implicate dysfunctional NK cells in the lack of tumor clearance in mice.

[This corrects the article DOI: 10.1371/journal.pgen.1008841.].