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Oxygen limitation has been proposed as one of the key factors that limits body size at high temperatures (the oxygen-temperature hypothesis). Geographic patterns in body size are thought to be driven in part by the effects of temperature on oxygen supply and demand, particularly when the increased oxygen demand of tissues at higher temperatures outpaces the ability of large organisms to supply internal tissues with oxygen. We tested the effects of temperature on the rate of oxygen consumption of two temperate sea spider (Pycnogonida) species, Achelia chelata and Achelia gracilipes, across a range of body sizes. We measured oxygen consumption at 5 temperatures: 12, 16, 20, 24, and 28 [degrees]C. Oxygen consumption of both species increased significantly with temperature, but the effect did not depend on body size; thus, we found no evidence to support the oxygen-temperature hypothesis. While previous interspecific studies on Antarctic pycnogonids have found that larger-bodied animals have more porous cuticles, thus potentially offsetting their higher aerobic metabolic demand by increasing oxygen diffusivity, the pore area of the cuticle of the two temperate species did not change with body size. This suggests that the generally small size of warm-water sea spiders may be due to selective factors other than oxygen limitation., Introduction Almost all aspects of an organism's physiology are influenced by body size (Kingsolver and Huey, 2008). As a result, the physiological and environmental factors that underlie evolutionary or acclimatory [...]

Models of range expansion have independently explored fitness consequences of life history trait evolution and increased rates of genetic drift—or "allele surfing"—during spatial spread, but no previous model has examined the interactions between these two processes. Here, using spatially explicit simulations, we explore an ecologically complex range expansion scenario that combines density-dependent selection with allele surfing to asses the genetic and fitness consequences of density-dependent selection on the evolution of life history traits. We demonstrate that density-dependent selection on the range edge acts differently depending on the life history trait and can either diminish or enhance allele surfing. Specifically, we show that selection at the range edge is always weaker at sites affecting competitive ability (K -selected traits) than at sites affecting birth rate (r -selected traits). We then link differences in the frequency of deleterious mutations to differences in the efficacy of selection and rate of mutation accumulation across distinct life history traits. Finally, we demonstrate that the observed fitness consequences of allele surfing depend on the population density in which expansion load is measured. Our work highlights the complex relationship between ecology and expressed genetic load, which will be important to consider when interpreting both experimental and field studies of range expansion. [ABSTRACT FROM AUTHOR]

Abstract. Essentially all surfaces of marine plants and animals host epibionts. These organisms may harm their hosts in a number of ways, including impeding gas exchange or increasing the costs [...]

Oxygen bioavailability is declining in aquatic systems worldwide as a result of climate change and other anthropogenic stressors. For aquatic organisms, the consequences are poorly known but are likely to reflect both direct effects of declining oxygen bioavailability and interactions between oxygen and other stressors, including two—warming and acidification—that have received substantial attention in recent decades and that typically accompany oxygen changes. Drawing on the collected papers in this symposium volume ("An Oxygen Perspective on Climate Change"), we outline the causes and consequences of declining oxygen bioavailability. First, we discuss the scope of natural and predicted anthropogenic changes in aquatic oxygen levels. Although modern organisms are the result of long evolutionary histories during which they were exposed to natural oxygen regimes, anthropogenic change is now exposing them to more extreme conditions and novel combinations of low oxygen with other stressors. Second, we identify behavioral and physiological mechanisms that underlie the interactive effects of oxygen with other stressors, and we assess the range of potential organismal responses to oxygen limitation that occur across levels of biological organization and over multiple timescales. We argue that metabolism and energetics provide a powerful and unifying framework for understanding organism-oxygen interactions. Third, we conclude by outlining a set of approaches for maximizing the effectiveness of future work, including focusing on long-term experiments using biologically realistic variation in experimental factors and taking truly cross-disciplinary and integrative approaches to understanding and predicting future effects. [ABSTRACT FROM AUTHOR]

Egg size is one of the most important aspects of the life history of free-spawning marine organisms, and it is correlated with larval developmental mode and many other lite-history characters. Egg size is simple to measure and data are available for a wide range of taxa, but we have a limited understanding of' how large and small eggs differ in composition; size is not always the best measure of the characters under selection. Large eggs are generally considered to reflect increased maternal investment, but egg size alone can be a poor predictor of energetic content within and among taxa. We review techniques that have been used to measure the energetic content and biochemical makeup of invertebrate eggs and point out the strengths and difficulties associated with each. We also suggest a number of comparative and descriptive approaches to biochemical constituent analysis that would strengthen our understanding of how natural selection shapes oogenic strategies. Finally, we highlight recent empirical research on the intrinsic factors that drive intraspeeiric variation in egg size. We also highlight the relative paucity of these data in the literature and provide some suggestions for future research directions., Introduction Egg size is one of the most important and often-studied aspects of the life history of marine organisms, and much attention has focused on the ecological factors that drive [...]

Siboglinid worms are a group of gutless marine annelids that are nutritionally dependent upon endosymbiotic bacteria. Four major groups of siboglinids are known--vestimentiferans, moniliferans, Osedax spp. and frenulates. Although endosymbionts of vestimentiferans and Osedax spp. have been previously characterized, little is currently known about endosymbiotic bacteria associated with frenulate and moniliferan siboglinids. This is particularly surprising given that frenulates are the most diverse and widely distributed group of siboglinids. Here, we molecularly characterize endosymbiotic bacteria associated with the frenulate siboglinid Siboglinum fiordicum by using 16S rDNA ribotyping in concert with laser-capture microdissection (LCM). Phylogenetic analysis indicates that at least three major clades of endosymbiotic γ-proteobacteria associate with siboglinid annelids, with each clade corresponding to a major siboglinid group. S. fiordicum endosymbionts are a group of γ-proteobacteria that are divergent from bacteria associated with vestimentiferan or Osedax hosts. Interestingly, symbionts of S. fiordicum, from Norway, are most closely related to symbionts of the frenulate Oligobrachia mashikoi from Japan, suggesting that symbionts of frenulates may share common evolutionary history or metabolic features., Introduction Siboglinids, previously known as the phyla Pogonophora and Vestimentifera, are now recognized as a monophyletic clade within annelid worms (McHugh, 1997; Black et al., 1997; Halanych et al., 2001; [...]

The consequences of changes in egg size for the development of marine invertebrates have been the subject of much theoretical and experimental work. Models that explore larval developmental modes in the context of maternal investment per offspring are often couched in an energetic framework, but the relationships between egg size and the energetics of larval development are poorly understood. We used blastomere separations to examine how experimental reductions in egg size affected (1) larval metabolic rate and (2) larval resistance to starvation. We found that separating blastomeres at the 2- and 4-cell stage resulted in average reductions of 50% and 75%, respectively, in larval metabolic rate. This suggests that, in an experimental context, mass-specific metabolic rate does not change with egg size. We also found that a 50% reduction in egg volume did not reduce the resistance of larvae to starvation when particulate food was withheld. This suggests that the material supplied to larvae in the egg is used primarily for construction of the larval body, rather than as a buffer against starvation or as a means of reducing reliance on exogenous fuel to sustain maintenance metabolism., Introduction Egg size has traditionally been viewed as a critical factor in the evolution of complex life histories of marine invertebrates. Egg size is linked to fundamental traits such as [...]

Implications of customer complaint websites on public perceptions are examined.

An understanding of the biochemical and physiological energetics of lecithotrophic development is useful for interpreting patterns of larval development, dispersal potential, and life-history evolution. This study investigated the metabolic rates and use of biochemical reserves in two species of abalone, Haliotis fulgens (the green abalone) and H. sorenseni (the white abalone). Larvae of H. fulgens utilized triacylglycerol as a primary source of endogenous energy reserves for development (~50% depletion from egg to metamorphic competence). Amounts of phospholipid remained constant, and protein dropped by about 30%. After embryogenesis, larvae of H. fulgens had oxygen consumption rates of 81.7 ± 5.9 (SE) pmol larva [h.sup.-1] [h.sup.-1] at 15 °C through subsequent development. The loss of biochemical reserves fully met the needs of metabolism, as measured by oxygen consumption. Larvae of H. sorenseni were examined during later larval development and were metabolically and biochemically similar to H. fulgens larvae at a comparable stage. Metabolic rates of both species were very similar to previous data for a congener, H. rufescens, suggesting that larval metabolism and energy utilization may be conserved among closely related species that also share similar developmental morphology and feeding modes., Introduction Most marine invertebrates have a distinct larval phase in their early life histories and can be divided into species whose larvae feed in the plankton (planktotrophic) and species whose [...]

Water temperatures on river networks fluctuate in time and over space. This variation creates complex thermal regimes through which fishes move over the course of their lives. Using water temperature data collected every 30 min for 6 y at 45 locations throughout the Snoqualmie River Basin, Washington, USA, we developed a set of metrics representing facets of the thermal regime important to native Chinook Salmon (Oncorhynchus tshawytscha) and Bull Trout (Salvelinus confluentus) and to non-native Largemouth Bass (Micropterus salmoides) during multiple life-history stages. We modeled these facets using spatial stream network models (SSNMs) built from covariates describing landform, land use, and climate to better understand the potential ecological drivers of thermal habitats for these fishes. The explanatory power (predictive r 2) of the final SSNMs ranged from 23 to 97%, with at least ½ the models >69%. The best models tended to include climate and landform covariates, with elevation and mean annual air temperature most often included. The relative contribution of each SSNM component differed by species: thermal metric models for Chinook Salmon tended to have a covariate- and site-based structure, those for Bull Trout tended to have a yearly structure, and those for Largemouth Bass tended to have a spatial structure. We applied our models to map the thermal landscape in ways that should be of particular interest to fish managers. Given the challenging lack of empirical data for rare fish species or fish species that are currently not present, we illustrate how the proliferation of fine-scale temperature data can be leveraged to provide ecological insight. For example, we identified several tributaries and small low-elevation reaches as areas potentially worthy of protection efforts for Chinook Salmon, and we identified the mainstem Snoqualmie River as an area of potential interaction between native salmon and non-native bass. [ABSTRACT FROM AUTHOR]

Adaptation to local conditions can increase species' geographic distributions and rates of diversification, but which components of the environment commonly drive local adaptation—particularly the importance of biotic interactions—is unclear. Biotic interactions should drive local adaptation when they impose consistent divergent selection; if this is common, we expect transplant experiments to detect more frequent and stronger local adaptation when biotic interactions are left intact. We tested this hypothesis using a meta-analysis of transplant experiments from >125 studies (mostly of plants). Overall, local adaptation was common, and biotic interactions affected fitness. Nevertheless, local adaptation was neither more common nor stronger when biotic interactions were left intact, either between experimental treatments within studies (control vs. biotic interactions experimentally manipulated) or between studies that used natural versus biotically altered transplant environments. However, the effect of ameliorating negative interactions varied with latitude, suggesting that interactions may promote local adaptation more often in tropical than in temperate ecosystems, although few tropical studies were available to test this. Our results suggest that biotic interactions often fail to drive local adaptation even though they strongly affect fitness, perhaps because temperate biotic environments are unpredictable at the spatiotemporal scales required for local adaptation. [ABSTRACT FROM AUTHOR]

The article focuses on interdisciplinary project that encompasses digital humanities such as Early Modern Recipes Online Collective (EMROC) which has discovered many challenges and rewards. It mentions future research endeavors in sustainable and exciting ways through cross-campus exchanges and Citizen Humanities initiatives. It also mentions families across generations and detailing how to make diverse medicines and foods and crowdsourcing.

Determining the causes of geographic range limits is a fundamental problem in ecology, evolution, and conservation biology. Range limits arise because of fitness and dispersal limitation, which yield contrasting predictions about habitat suitability and occupancy of suitable habitat across geographic ranges. If a range edge is limited primarily by fitness, occupancy of suitable habitat should be high, habitat suitability should decline toward the edge, and no suitable habitat should exist beyond it. In contrast, a range edge limited primarily by dispersal should have unoccupied but suitable habitat at and beyond the edge. We built ecological niche models relating occurrence records for the scarlet monkeyflower (Erythranthe cardinalis) to climatic variables and applied these models to independent data from systematic, range-wide surveys of presence and absence to estimate the availability and occupancy of climatically suitable habitat. We found that fitness limitation predominated over dispersal limitation, but dispersal limitation also played a role at the poleward edge. These results are consistent with the hypothesis that dispersal limitation is more important along shallow environmental gradients and also suggest that synergy between dispersal and fitness limitation can contribute to colonization failure. The framework used here is validated by independent data and could be readily applied to inferring causes of range limits in many other species. [ABSTRACT FROM AUTHOR]

The biotic and abiotic factors that facilitate or hinder species range expansions are many and complex. We examine the impact of two genetic processes and their interaction on fitness at expanding range edges: local maladaptation resulting from the presence of an environmental gradient and expansion load resulting from increased genetic drift at the range edge. Results from spatially explicit simulations indicate that the presence of an environmental gradient during range expansion reduces expansion load; conversely, increasing expansion load allows only locally adapted populations to persist at the range edge. Increased maladaptation reduces the speed of range expansion, resulting in less genetic drift at the expanding front and more immigration from the range center, therefore reducing expansion load at the range edge. These results may have ramifications for species being forced to shift their ranges because of climate change or other anthropogenic changes. If rapidly changing climate leads to faster expansion as populations track their shifting climatic optima, populations may suffer increased expansion load beyond previous expectations. [ABSTRACT FROM AUTHOR]

Trade-offs among traits are important for maintaining biodiversity, but the role of natural selection in their construction is not often known. It is possible that trade-offs reflect fundamental constraints, negative correlational selection, or directional selection operating on costly, redundant traits. In a Sonoran Desert community of winter annual plants, we have identified a trade-off between relative growth rate and water-use efficiency among species, such that species with high relative growth rate have low water-use efficiency and vice versa. We measured selection on water-use efficiency, relative growth rate, and underlying traits within populations of four species at two study sites with different average climates. Phenotypic trait correlations within species did not match the among-species trade-off. In fact, for two species with high water-use efficiency, individuals with high relative growth rate also had high water-use efficiency. All populations experienced positive directional selection for water-use efficiency and relative growth rate. Selection tended to be stronger on water-use efficiency at the warmer and drier site, and selection on relative growth rate tended to be stronger at the cooler and wetter site. Our results indicate that directional natural selection favors a phenotype not observed among species in the community, suggesting that the amongspecies trade-off could be due to pervasive genetic constraints, perhaps acting in concert with processes of community assembly. [ABSTRACT FROM AUTHOR]

Geographic range margins offer testing grounds for limits to adaptation. If range limits are concordant with niche limits, range expansions require the evolution of new phenotypes that can maintain populations beyond current range margins. However, many species' range margins appear static over time, suggesting limits on the ability of marginal populations to evolve appropriate phenotypes. A potential explanation is the swamping gene flow hypothesis, which posits that asymmetrical gene flow from large, well-adapted central populations prevents marginal populations from locally adapting.We present an empirical framework for combining gene flow, environment, and fitness-related phenotypes to infer the potential for maladaptation, and we demonstrate its application using the scarlet monkeyflower Mimulus cardinalis. We grew individuals sampled from populations on a latitudinal transect under varied temperatures and determined the phenotypic deviation (PD), the mismatch between phenotype and local environment. We inferred gene flow among populations and predicted that populations receiving the most temperature- or latitude-weighted immigration would show the greatest PD and that these populations were likely marginal.We found asymmetrical gene flow from central to marginal populations. Populations with more latitude-weighted immigration had significantly greater PD but were not necessarily marginal. Gene flow may limit local adaptation in this species, but swamping gene flow is unlikely to explain its northern range limit. [ABSTRACT FROM AUTHOR]

Information about several papers discussed at a conference on early modern women is presented. Topics include on the Spanish tales on the vision journeys to the U.S., overt negotiations strategies used by nuns and female opera singers, and epistolary writings. The conference featured several guests including Barbara Watson Andaya, Penny Howell Jolly, and Megan Matchinske.

In "The Winter's Tale" the image of the garden represents the corporeal body—the intersection between the human body and the body of/as the nation state. "The Winter's Tale" associates female bodies with the garden; as royal women and thereby producers of monarchal heirs, Hermione's and Perdita's bodies intimately affect the health and well-being of the state itself. Early in the play, Hermione's reference to the garden incites Leontes' jealous rage. Leontes literally and figuratively situates Hermione as a descendent of Eve who causes the ruin of the Edenic kingdom through her perceived desires. Hermione's alleged crime is against the nation, for royal infidelity is legally treason. As the garden comes to represent Hermione's disputed body, it also emblematizes Perdita's virginal body. The image of the garden returns in the fifth act when Paulina presents the royal body of the assumed dead queen Hermione as statuary in her "gallery." In the garden, where the corporeal body appears as mechanical automata, the Queen regains her lost husband, her place as wife, and her status as co-ruler of the state. [ABSTRACT FROM AUTHOR]

The article discusses the design and provenance of Romanesque marble portals from defunct Randolph Hearst collection. The portals, decorated with low-relief ornament, are under the custody of the Detroit Institute of Arts, The Cloisters, The Metropolitan Museum of Art and the Los Angeles County Museum. Portals at the Los Angeles museum dates back to 11th century; the one in Detroit dates from 12th century. The portals are compared with other antique portals to determine whether they originated from Southern France.

A recent empirical literature has shaken economists' confidence in the value of aggregate (industry-level) data to illuminate production relationships. But the statistical finding "you cannot aggregate," however well documented, is not an economic explanation. Plant level relationships do aggregate in Depression-era blast furnace operations despite the presence of very substantial interplant heterogeneity, the most common economic cause of nonaggregability. The economic explanation of this lies in poor short-run substitutability of one plant's output for another's. Substitutability determines the importance of composition effects in understanding aggregate time series, constrains the potential cleansing effects of recessions, and therefore influences industry evolution quite broadly. [ABSTRACT FROM AUTHOR]