Inter‐oceanic variation in patterns of host‐associated divergence in a seabird ectoparasite

Aim Parasites with global distributions and wide host spectra provide excellent models for exploring the factors that drive parasite diversification. Here, we tested the relative force of host and geography in shaping population structure of a widely distributed and common ectoparasite of colonial seabirds, the tick Ixodes uriae. Location Two natural geographic replicates of the system: numerous seabird colonies of the North Pacific and North Atlantic Ocean basins. Methods Using eight microsatellite markers and tick samples from a suite of multi‐specific seabird colonies, we examined tick population structure in the North Pacific and compare patterns of diversity and structure to those in the Atlantic basin. Analyses included population genetic estimations of diversity and population differentiation, exploratory multivariate analyses, and Bayesian clustering approaches. These different analyses explicitly took into account both the geographic distance among colonies and host use by the tick. Results Overall, little geographic structure was observed among Pacific tick populations. However, host‐related genetic differentiation was evident, but was variable among host types and lower than in the North Atlantic. Main conclusions Tick population structure is concordant with the genetic structure observed in seabird host species within each ocean basin, where seabird populations tend to be less structured in the North Pacific than in the North Atlantic. Reduced tick genetic structure in the North Pacific suggests that host movement among colonies, and thus tick dispersal, is higher in this region. In addition to information on parasite diversity and gene flow, our findings raise interesting questions about the subtle ways that host behaviour, distribution and phylogeographic history shape the genetics of associated parasites across geographic landscapes.     

Race and ethnicity are not primary determinants in utilizing veterinary services in underserved communities in the United States

A retrospective database analysis (2011–2015) evaluated associations between race and ethnicity and veterinary service utilization by sampling 83,260 companion animals whose guardians (owners) self-identified as White, Black, or Latino/a from 39 Humane Society of the United States Pets for Life (PFL) sites across the United States. Controlling for socioeconomic status, the percentage of nonhuman animals sterilized through PFL whose owners were Latino/a or Black was substantially higher than in previously reported findings. While Latinos/as had the highest mean number of days from first contact with the program to consent, they also had the highest percentage of owners accepting the voucher during initial contact. Logistic regression models suggested that although meaningful, race and ethnicity were not primary determinants of veterinary service utilization. When veterinary and animal welfare organizations deliberately remove structural barriers embedded with racial inequalities, individuals, regardless of race and ethnicity, proceed with companion-animal sterilization. Therefore, service providers must use unbiased, informed, and culturally competent practices to improve companion-animal welfare through the optimization of veterinary services, including spay and neuter.     

Chemical races in the red alga Laurencia nipponica (Rhodomelaceae, Ceramiales)

Genetic variation in the synthesis of halogenated secondary metabolites in the Japanese marine red alga Laurencia nipponica Yamada (Rhodomelaceae, Ceramiales) has been investigated in laboratory crossing experiments and chemical analyses, F₁ tetrasporophytes and F₁ gametophytes resulting from crosses within chemical races produced major metabolites characteristic of these races. F₁ tetrasporophytes derived from reciprocal interracial crosses produced: (i) both parental types of secondary metabolites; (ii) either of the parental types; or (iii) a further major compound in addition to both parental types or in addition to either of the parental types. The latter cases suggest that hybrid-specific products were formed by the combined enzymatic complements of the parents, as F₁ gametophytes derived from these interracial F₁ tetrasporophytes yielded one or other of their parental products in an approximate 1:1 ratio. The population structure was analyzed at localities in Hokkaido, where two of the chemical races occur sympatrically. At Usujiri (Minami-kayabe), where the prepacifenol race and the laureatin race were sym-patric, hybrid gametophytes (recombination type) were found in high frequency in addition to hybrid tetra sporophytes, which strongly suggests that a new, pre-pacifenol/laureatm race is beginning to be produced by natural hybridization and recombination. By contrast, at Oshoro Bay, where the laurencin race and the epi-lauraliene race grew together, the interracial hybrids were rare: only a few tetrasporophytes (probably F₁ generation) were found, suggesting that racial integrity may be retained by habitat segregation and/or the absence of recombination-type gametophytes.     

Coevolutionary interactions in a host–parasite system

Interactions between parasitic cuckoos and their hosts represent a classic example of coevolution, where adaptations in the parasite to exploit the host select for defences, which in turn select for new parasite adaptations. Current interactions between the two parties may be at an evolutionary equilibrium or, alternatively, a coevolutionary arms race may be taking place. By taking into account the effect of gene flow in 15 European magpie ( Pica pica ) populations, we studied the coevolutionary interactions with its brood parasite, the great spotted cuckoo ( Clamator glandarius ). Our results suggest that, in Europe, magpies and cuckoos are engaged in an ongoing coevolutionary process because, despite controlling for the large amounts of gene flow among different magpie populations, we still found a positive relationship between host defence (i.e. foreign egg recognition and rejection) and parasite selection pressure.     

A competitive marathon race decreases neutrophil functions in athletes

A full marathon is the longest running race in official track events and is a form of acute exercise. However, no studies have examined the acute neutrophil function response to a competitive marathon race. Thirty‐six male athletes who had just completed the 42.195 km course of the 50th Beppu‐Oita Mainichi Marathon were enrolled in this study. Neutrophil oxidative burst activity, phagocytic activity and expression of CD11b and CD16 per cell were measured by flow cytometry immediately before and after the marathon. Total leukocyte/neutrophil counts increased significantly (p < 0.001), whereas total oxidative burst activity per neutrophil cell decreased significantly after the race (p < 0.001). Furthermore, total phagocytic activity per neutrophil cell also decreased after the race, although it was not significant (p = 0.08). Although CD11b expression per cell did not change, the expression of CD16 per cell significantly decreased (p < 0.001) after the race. In conclusion, a competitive marathon race decreased neutrophil functions (oxidative burst activity and phagocytic activity), which may be partly due to a decrease in CD16 expression. The increase in total neutrophil counts might reflect a compensatory response to counteract the decrease in neutrophil functions. Copyright © 2003 John Wiley & Sons, Ltd.     

The impact of redefined species limits in Palame (Coleoptera: Cerambycidae: Lamiinae: Acanthocinini) on assessments of host, seasonal, and stratum specificity

Assumptions about the host and stratum specificity of tropical insects are routinely incorporated into estimates of global species richness, but few empirical studies reliably assess tropical insect specificity. In French Guiana, cerambycid beetles in the genus Palame reproduce exclusively in trees belonging to the Brazil nut family (Lecythidaceae). During a year-long rearing project, Palame anceps (Bates) emerged exclusively from a single host species, but P. crassimana Bates and P. mimetica Monné appeared to make seasonal changes in host affiliation. In the case of P. crassimana , dry season specimens could be distinguished from rainy season specimens by subtle differences in pubescence, but it was difficult to find diagnostic morphological characters supporting their delimitation as separate species. In order to detect genetic differentiation in Palame , 1049 bp of mitochondrial DNA (COI gene) were sequenced. The three nominal species of Palame yielded six haplotype groups, with sequence divergences among groups ranging from 8.27 to 17.56%. Species with apparent seasonal changes in host use included multiple distinct haplotype groups that I interpret to represent multiple species-level taxa. Insects considered generalized owing to temporal or geographical changes in host association may, with improved resolution in species limits, prove to be assemblages including relatively specialized cryptic species. © 2002 The Linnean Society of London, Biological Journal of the Linnean Society , 2002, 76 , 195–209.     

Impact of Firm-Based Environmental Standards on Subsidiaries and Their Suppliers: Evidence from Motorola-Penang

How successful are multinational corporations in extending their firm-based environmental standards to their subsidiaries and those subsidiaries' local suppliers in their global production networks in developing countries? We address this question through an in-depth case study of how Motorola, a prominent multinational electronics firm with an extensive global production network, is using a set of firm-based standards to meet several new stringent European Union environmental directives. The case study demonstrates that these firm-based standards appear to be enabling a major subsidiary and its suppliers in one developing economy to reduce the environmental intensities of their production activities. This finding suggests that the firm-based environmental standards of multinationals with extensive global production networks might contribute to a leveling up of environmental standards in subsidiaries and their local suppliers, rather than a "race to the bottom", thus reinforcing the technique or intensity effects associated with open trade, investment, and technology policies.     

White Ethnogenesis and Gradual Capitalism: Perspectives from Colonial Archaeological Sites in the Chesapeake

The piecemeal development of capitalist socioeconomic systems in the colonial Chesapeake was deeply intertwined with projects of white ethnogenesis. Crafting a sense of "groupness" along lines perceived as racial required free "whites" to remain economically and socially interdependent. A variety of strategies and material forms—including reciprocal exchanges, hall-parlor house plans, and earthfast construction—facilitated this cohesion. Such integrative tactics coexisted in colonists' behavioral repertoires with more "capitalistic" strategies that prioritized private profit over social obligation. Colonists' deployment of diverse social strategies reflects a complex calculus assessing the benefits of economic autonomy against the benefits of ethnic ("white") solidarity. These dynamics can be illustrated through an 18th-century archaeological site at Flowerdew Hundred in the Chesapeake.