An Ecological Study of Mourning Doves in a Cold Desert Ecosystem on the Idaho National Engineering Laboratory

Mourning dove (Zenaida macroura) use of and movements around man-made ponds, as well as dove nesting ecology, were studied from 1983 through 1985 on the Idaho National Engineering Laboratory (INEL). Relative dove use was higher (P \u3c 0.01) on some ponds than others, and multiple regression revealed a positive association (R 2 = 0.49) between relative use and the geographic isolation of ponds. Two peaks in diurnal pond use were exhibited by doves on the INEL: the mourning peak began around 0800 and lasted until approximately 1300, and the evening peak began at about 2030 and ended by 2150. Seasonal pond use fluctuated slightly through the summer then dropped rapidly in early September. Average and average maximum movements indicated that the 41 mourning doves trapped and fitted with radio-transmitters at the Test Reactor Area (TRA) and the Naval Research Facility (NRF) did not move off of the INEL on a regular basis. The average distance from mourning dove locations to TRA and NRF was \u3c2.0 km, and the average maximum dove location was \u3c3.5 km from either facility. Average (\u3c2.0 km) and average maximum (\u3c3.5 km) distances were also measured from dove locations to watering sites. Doves captured at both TRA and NRF moved, on average, 1.5 km from their nests; the average maximum distance from a dove\u27s location to its nest was 2.8 and 5.4 km for doves caught at TRA and NRF. The average maximum distance between any 2 locations (for the same individual) at both TRA and NRF was \u3c4.0 km. Mourning doves on the INEL are primarily ground nesters. Nesting success averaged 68% per year, with 1.8 fledglings produced per successful nest. Nesting densities averaged 0.02 nests/ha during the study. Three peaks in hatching occurred on the INEL: 1 during the fourth week of June, another during the third week of July, and a third during the first and second weeks of August. Annual production estimates for the INEL ranged from 11,300 to 17,000 doves, based on a model using 2 and 3 nesting attempts per summer. No differences (P \u3e 0.05) were indicated in the percent coverage of shrubs, grasses, forbs, and bare ground, as measured with the line-intercept method, in the 5-m area surrounding dove nests and paired random sites. However, a difference in the percentage of grass cover and bare ground, as measured with a point-frame, was indicated in the 1-m2 (microhabitat) centered on the nest or random site; nest sites contained more grass (P = 0.02) and less bare ground (P = 0.02) than random sites. No difference was found between nest and random site microhabitats in the percentage of shrub or forb cover. Also, no difference was indicated by chi-square analysis in vertical vegetation obstruction, as measured from 15 m, between nest and random sites. Twenty-three of the 28 ground nests on the INEL were located under big sagebrush (Artemisia tridentata)

Rodent-Mediated Interactions Among Seed Species of Differing Quality in a Shrubsteppe Ecosystem

Interactions among seeds, mediated by granivorous rodents, are likely to play a strong role in shrubsteppe ecosystem restoration. Past studies typically consider only pairwise interactions between preferred and less preferred seed species, whereas rangeland seedings are likely to contain more than 2 seed species, potentially leading to complex interactions. We examined how the relative proportion of seeds in a 3-species polyculture changes rodent seed selectivity (i.e., removal) and indirect interactions among seeds. We presented 2 rodent species, Peromyscus maniculatus (deer mice) andPerognathus parvus (pocket mice), in arenas with 3-species seed mixtures that varied in the proportion of a highly preferred, moderately preferred, and least preferred seed species, based on preferences determined in this study. We then conducted a field experiment in a pocket mouse–dominated ecosystem with the same 3-species seed mixtures in both “treated” (reduced shrub and increased forb cover) and “untreated” shrubsteppe. In the arena experiment, we found that rodents removed more of the highly preferred seed when the proportions of all 3 seeds were equal. Moderately preferred seeds experienced increased removal when the least preferred seed was in highest proportion. Removal of the least preferred seed increased when the highly preferred seed was in highest proportion. In the field experiment, results were similar to those from the arena experiment and did not differ between treated and untreated shrubsteppe areas. Though our results suggest that 3-species mixtures induce complex interactions among seeds, managers applying these results to restoration efforts should carefully consider the rodent community present and the potential fate of removed seeds

Selection at a single locus leads to widespread expansion of toxoplasma gondii lineages that are virulent in mice

The determinants of virulence are rarely defined for eukaryotic parasites such as T. gondii, a widespread parasite of mammals that also infects humans, sometimes with serious consequences. Recent laboratory studies have established that variation in a single secreted protein, a serine/threonine kinase known as ROPO18, controls whether or not mice survive infection. Here, we establish the extent and nature of variation in ROP18among a collection of parasite strains from geographically diverse regions. Compared to other genes, ROP18 showed extremely high levels of diversification and changes in expression level, which correlated with severity of infection in mice. Comparison with an out-group demonstrated that changes in the upstream region that regulates expression of ROP18 led to an historical increase in the expression and exposed the protein to diversifying selective pressure. Surprisingly, only three atypically distinct protein variants exist despite marked genetic divergence elsewhere in the genome. These three forms of ROP18 are likely adaptations for different niches in nature, and they confer markedly different virulence to mice. The widespread distribution of a single mouse-virulent allele among geographically and genetically disparate parasites may have consequences for transmission and disease in other hosts, including humans

Garden and landscape-scale correlates of moths of differing conservation status: significant effects of urbanization and habitat diversity

Moths are abundant and ubiquitous in vegetated terrestrial environments and are pollinators, important herbivores of wild plants, and food for birds, bats and rodents. In recent years, many once abundant and widespread species have shown sharp declines that have been cited by some as indicative of a widespread insect biodiversity crisis. Likely causes of these declines include agricultural intensification, light pollution, climate change, and urbanization; however, the real underlying cause(s) is still open to conjecture. We used data collected from the citizen science Garden Moth Scheme (GMS) to explore the spatial association between the abundance of 195 widespread British species of moth, and garden habitat and landscape features, to see if spatial habitat and landscape associations varied for species of differing conservation status. We found that associations with habitat and landscape composition were species-specific, but that there were consistent trends in species richness and total moth abundance. Gardens with more diverse and extensive microhabitats were associated with higher species richness and moth abundance; gardens near to the coast were associated with higher richness and moth abundance; and gardens in more urbanized locations were associated with lower species richness and moth abundance. The same trends were also found for species classified as increasing, declining and vulnerable under IUCN (World Conservation Union) criteria

Measurement of the rate of nu_e + d --> p + p + e^- interactions produced by 8B solar neutrinos at the Sudbury Neutrino Observatory

Solar neutrinos from the decay of $^8$B have been detected at the Sudbury Neutrino Observatory (SNO) via the charged current (CC) reaction on deuterium and by the elastic scattering (ES) of electrons. The CC reaction is sensitive exclusively to nu_e's, while the ES reaction also has a small sensitivity to nu_mu's and nu_tau's. The flux of nu_e's from ^8B decay measured by the CC reaction rate is \phi^CC(nu_e) = 1.75 +/- 0.07 (stat)+0.12/-0.11 (sys.) +/- 0.05(theor) x 10^6 /cm^2 s. Assuming no flavor transformation, the flux inferred from the ES reaction rate is \phi^ES(nu_x) = 2.39+/-0.34 (stat.)+0.16}/-0.14 (sys) x 10^6 /cm^2 s. Comparison of \phi^CC(nu_e) to the Super-Kamiokande Collaboration's precision value of \phi^ES(\nu_x) yields a 3.3 sigma difference, providing evidence that there is a non-electron flavor active neutrino component in the solar flux. The total flux of active ^8B neutrinos is thus determined to be 5.44 +/-0.99 x 10^6/cm^2 s, in close agreement with the predictions of solar models.Comment: 6 pages (LaTex), 3 figures, submitted to Phys. Rev. Letter

Britain and globalization

Many perspectives on globalization see it as differentiated in its effects and reception, culturally driven, either pre-modern or post-modern, best captured by globalist or sceptical perspectives, and an equalising phenomenon. This article discusses the British experience of globalization in the light of such approaches and argues that looking at this case gives an alternative view. Six themes on globalization are explored across four areas of the British experience of globalization. It is argued that in Britain globalization is, in contrast to the approaches outlined above, differentiated but also generalising, economically driven, modern, best understood with a mix of globalist and sceptical perspectives and structured by power, inequality and conflict. It is also argued that the British experience of globalization is a specific one and that Britain is a very globalized and globalizing country, economically, culturally and politically

Induction of autophagy by spermidine promotes longevity.

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The selective Cox-2 inhibitor Celecoxib suppresses angiogenesis and growth of secondary bone tumors: An intravital microscopy study in mice

BACKGROUND: The inhibition of angiogenesis is a promising strategy for the treatment of malignant primary and secondary tumors in addition to established therapies such as surgery, chemotherapy, and radiation. There is strong experimental evidence in primary tumors that Cyclooxygenase-2 (Cox-2) inhibition is a potent mechanism to reduce angiogenesis. For bone metastases which occur in up to 85% of the most frequent malignant primary tumors, the effects of Cox-2 inhibition on angiogenesis and tumor growth remain still unclear. Therefore, the aim of this study was to investigate the effects of Celecoxib, a selective Cox-2 inhibitor, on angiogenesis, microcirculation and growth of secondary bone tumors. METHODS: In 10 male severe combined immunodeficient (SCID) mice, pieces of A549 lung carcinomas were implanted into a newly developed cranial window preparation where the calvaria serves as the site for orthotopic implantation of the tumors. From day 8 after tumor implantation, five animals (Celecoxib) were treated daily with Celecoxib (30 mg/kg body weight, s.c.), and five animals (Control) with the equivalent amount of the CMC-based vehicle. Angiogenesis, microcirculation, and growth of A549 tumors were analyzed by means of intravital microscopy. Apoptosis was quantified using the TUNEL assay. RESULTS: Treatment with Celecoxib reduced both microvessel density and tumor growth. TUNEL reaction showed an increase in apoptotic cell death of tumor cells after treatment with Celecoxib as compared to Controls. CONCLUSION: Celecoxib is a potent inhibitor of tumor growth of secondary bone tumors in vivo which can be explained by its anti-angiogenic and pro-apoptotic effects. The results indicate that a combination of established therapy regimes with Cox-2 inhibition represents a possible application for the treatment of bone metastases