bluuebunny/crossref_metadata_2025_split huggingface dataset:
Does mobility explain variation in colonisation and population recovery among stream fishes?
Authors: ALBANESE BRETT , ANGERMEIER PAUL L. , PETERSON JAMES T. 
Published: March 2009

Summary1. Colonisation and population recovery are crucial to species persistence in environmentally variable ecosystems, but are poorly understood processes. After documenting movement rates for several species of stream fish, we predicted that this variable would influence colonisation rates more strongly than local abundance, per cent occupancy, body size and taxonomic family. We also predicted that populations of species with higher movement rates would recover more rapidly than species with lower movement rates and that assemblage structure would change accordingly.2. To test these predictions, we removed fishes from a headwater and a mainstem creek in southwest Virginia and monitored colonisation over a 2‐year period. Using an information–theoretic approach, we evaluated the relative plausibility of 15 alternative models containing different combinations of our predictor variables. Our best‐supported model contained movement rate and abundance and was 41 times more likely to account for observed patterns in colonisation rates than the next‐best model. Movement rate and abundance were both positively related to colonisation rates and explained 88% of the variation in colonisation rates among species.3. Population recovery, measured as the per cent of initial abundance restored, was also positively associated with movement rate. One species recovered within 3 months, most recovered within 2 years, but two species still had not recovered after 2 years. Despite high variation in recovery, the removal had only a slight impact on assemblage structure because species that were abundant in pre‐removal samples were also abundant in post‐removal samples.4. The significance of interspecific variation in colonisation and recovery rates has been underappreciated because of the widely documented recovery of stream fish assemblages following fish kills and small‐scale experimental defaunations. Our results indicate that recovery of the overall assemblage does not imply recovery of each component species. Populations of species that are rare and less mobile will recover more slowly and will be more vulnerable to extinction in systems where chemical spills, hydrological alteration, extreme droughts and other impacts are frequent.
Interpreting temporal variation in omnivore foraging ecology via stable isotope modelling
Authors: Kurle Carolyn M. 
Published: March 2009

Summary

The use of stable carbon (C) and nitrogen (N) isotopes (δ15N and δ13C, respectively) to delineate trophic patterns in wild animals is common in ecology. Their utility as a tool for interpreting temporal change in diet due to seasonality, migration, climate change or species invasion depends upon an understanding of the rates at which stable isotopes incorporate from diet into animal tissues. To best determine the foraging habits of invasive rats on island ecosystems and to illuminate the interpretation of wild omnivore diets in general, I investigated isotope incorporation rates of C and N in fur, liver, kidney, muscle, serum and red blood cells (RBC) from captive rats raised on a diet with low δ15N and δ13C values and switched to a diet with higher δ15N and δ13C values.
I used the reaction progress variable method (RPVM), a linear fitting procedure, to estimate whether a single or multiple compartment model best described isotope turnover in each tissue. Small sample Akaike Information criterion (AICc) model comparison analysis indicated that 1 compartment nonlinear models best described isotope incorporation rates for liver, RBC, muscle, and fur, whereas 2 compartment nonlinear models were best for serum and kidney.
I compared isotope incorporation rates using the RPVM versus nonlinear models. There were no differences in estimated isotope retention times between the model types for serum and kidney (except for N turnover in kidney from females). Isotope incorporation took longer when estimated using the nonlinear models for RBC, muscle, and fur, but was shorter for liver tissue.
There were no statistical differences between sexes in the isotope incorporation rates. I also found that N and C isotope incorporation rates were decoupled for liver, with C incorporating into liver tissue faster than N.
The data demonstrate the utility of analysing isotope ratios of multiple tissues from a single animal when estimating temporal variation in mammalian foraging ecology.
Evidence for the involvement of an alternate rodent host in the dynamics of introduced plague in prairie dogs
Authors: Stapp Paul , Salkeld Daniel J. , Franklin Heather A. , Kraft John P. , Tripp Daniel W. , Antolin Michael F. , Gage Kenneth L. 
Published: March 2009

SummaryThe introduction of plague to North America is a significant threat to colonies of prairie dogs (Cynomys ludovicianus), a species of conservation concern in the Great Plains. Other small rodents are exposed to the causative agent,Yersinia pestis, during or after epizootics; yet, its effect on these rodents is not known, and their role in transmitting and maintaining plague in the absence of prairie dogs remains unclear.We live‐trapped small rodents and collected their fleas on 11 colonies before, during and after plague epizootics in Colorado, USA, from 2004 to 2006. Molecular genetic (polymerase chain reaction) assays were used to identifyY. pestisin fleas.Abundance of northern grasshopper mice (Onychomys leucogaster) was low on sites following epizootics in 2004, and declined markedly following plague onset on other colonies in 2005. These changes coincided with exposure of grasshopper mice to plague, and with periods when mice became infested with large numbers of prairie dog fleas (Oropsylla hirsuta), including some that were infected withY. pestis. Additionally, severalPleochaetis exilis, fleas restricted to grasshopper mice and never found on prairie dogs on our site, were polymerase chain reaction‐positive forY. pestis, indicating that grasshopper mice can infect their own fleas. No changes in abundance of other rodent species could be attributed to plague, and no other rodents hostedO. hirsutaduring epizootics, or harbouredY. pestis‐infected fleas.In spring 2004, grasshopper mice were most numerous in colonies that suffered plague the following year, and the pattern of colony extinctions over a 12‐year period mirrored patterns of grasshopper mouse abundance in our study area, suggesting that colonies with high densities of grasshopper mice may be more susceptible to outbreaks. We speculate that grasshopper mice help spreadY. pestisduring epizootics through their ability to survive infection, harbour prairie dog fleas and, during their wide‐ranging movements, transport infected fleas among burrows, which functionally connects prairie dog coteries that would otherwise be socially distinct.
Landscape barriers reduce gene flow in an invasive carnivore: geographical and local genetic structure of American mink in Scotland
Authors: ZALEWSKI ANDRZEJ , PIERTNEY STUART B. , ZALEWSKA HANNA , LAMBIN XAVIER 
Published: March 2009

AbstractTo be effective, management programmes geared towards halting or reversing the spread of invasive species must focus on defined and defensible areas. This requires knowledge of the dispersal of non‐native species targeted for control to better understand invasion and recolonisation scenarios. We investigated the genetic structure of invasive American mink (Neovison vison) in Scotland, and incorporated landscape genetic approaches to examine resultant patterns in relation to geographical features that may influence dispersal. Populations of mink sampled from 10 sites in two regions (Argyll and Northeast Scotland) show a distinct genetic structure. First, the majority of pairwise population comparisons yielded FST values that were significantly greater than zero. Second, amova revealed that most of the genetic variance was attributable to differences among regions. Assignment tests placed 89 or more of individuals into their sampled region. Bayesian clustering methods grouped samples into two clusters according to their region of origin. Wombling approach identified the Cairngorms Mountains as a major impediment to gene flow between the regions. Mantel pairwise correlations between genetic and geographical distances estimated as least‐cost distance assuming a linear increase in the cost of movement with increasing elevation were higher than Euclidean distances or distance along waterways. Spatial autocorrelation analyses revealed stronger spatial structuring for females than for males. These results suggest that gene flow by American mink is restricted by landscape features (mountain ranges) and that eradication attempt should in the first instance break down the connectivity between management units separated by mountains.
Influence of life‐history variation on the genetic structure of two sympatric salamander taxa
Authors: STEELE C. A. , BAUMSTEIGER J. , STORFER ANDREW 
Published: March 2009

AbstractLife‐history characteristics are an important determinant of a species’ dispersal abilities. We predict that variation in life history can influence population‐level genetic patterns. To test this prediction, we estimate population‐level genetic structure for two sympatric species of stream‐breeding salamander. The Cope's giant salamander (Dicamptodon copei) rarely metamorphoses into a terrestrial adult, thereby limiting overland dispersal and potentially gene flow. In contrast, the Pacific giant salamander (D. tenebrosus) commonly metamorphoses, which is expected to facilitate overland dispersal and gene flow. Three sets of analyses based on microsatellite data support these hypotheses, showing that D. tenebrosus displays minimal population‐level genetic structuring and no pattern of isolation by distance, whereas D. copei displays a high degree of population‐level genetic structure and significant isolation by distance. Specifically, nearly all pairwise FST values were significantly different from 0 between populations of D. copei, with fewer than half the pairwise FST values significant from 0 in D. tenebrosus. Additionally, Structure analyses indicated eight genetic clusters for D. copei but only one genetic cluster for D. tenebrosus. Finally, Mantel tests showed significant correlations between stream and overland distance with genetic distance for D. copei but no significant correlations of either landscape feature for D. tenebrosus at the scale of the study. These results provide a case study of the link between life‐history variation and population genetic patterns while controlling for phylogeny and environmental variation.
Polygyny can increase rather than decrease genetic diversity contributed by males relative to females: evidence from red deer
Authors: PÉREZ‐GONZÁLEZ J. , MATEOS C. , CARRANZA J. 
Published: March 2009

AbstractPolygyny is expected to erode genetic variability by reducing the diversity of genetic contribution of males to the next generation, although empirical evidence shows that genetic variability in polygynous populations is not lost as rapidly as expected. We used microsatellite markers to study the genetic variability transmitted by mothers and fathers to offspring during a reproductive season in wild populations of a polygynous mammal, the red deer. Contrary to expectations, we found that males contributed more genetic diversity than females. Also, we compared study populations with different degrees of polygyny to find that polygyny was not related to a decrease in genetic diversity contributed by males. On the contrary, when population genetic diversity was relatively low, polygyny associated with higher genetic diversity of paternal lineage. Our results show that sexual selection, by favouring heterozygote individuals, may compensate the potential reduction of effective population size caused by polygyny, thus contributing to explain why genetic diversity is not depleted in polygynous systems.
End‐signature of deep‐marine basin‐fill, as a structurally confined low‐gradient clastic system: the Middle Eocene Guaso system, South‐central Spanish Pyrenees
Authors: SUTCLIFFE CLARE , PICKERING KEVIN T. 
Published: March 2009

AbstractThe ca 300 m thick Guaso system is the youngest part of the ca 4 km thick deep‐marine fill of the Middle Eocene Ainsa basin, Spanish Pyrenees. It is overlain by 150 to 200 m of fine‐grained slope, prodelta and deltaic sediments. The ca 25 discrete deep‐marine sandbodies within the Ainsa basin accumulated over ca 10 Myr, making eustasy the most likely control for coarse sand deposition (probably the ca 400 kyr Milankovitch mode). The first‐order control on basin‐scale accommodation, however, was tectonically‐driven subsidence. Previously, the Guaso sandbodies were interpreted as linked to deep erosional, canyon‐like features, but here it is argued that they are laterally extensive sandbodies, built by lateral‐switching of 3 to 10 m deep erosional channels, and confined only by basin structure during deposition. The Guaso system represents the end of deep‐marine deposition in a structurally‐confined, delta‐fed, low‐gradient clastic system. The critical end‐signature of deep‐marine deposition was a phase of differential tectonic uplift above the underlying (Boltaña) thrust creating a narrower and shallower basin morphology, thus allowing sedimentation to create a low‐gradient clastic system. Then, the next eustatic sea‐level fall was insufficient to permit the cutting of canyons or deeply‐incised slope channels, as had been the case earlier when the topographic relief between shelf and basin was at least several hundred metres greater. Such low‐gradient clastic systems may characterize the end‐signature for the infill of other shallowing‐up deep‐marine basins where a tectonic driver on subsidence is removed and/or differential uplift/subsidence leads to reduced sea floor gradients, leaving eustasy and sediment flux as the principal control on sediment supply.
Fine‐scale relief related to Late Holocene channel shifting within the floor of the upper Redondo Fan, offshore Southern California
Authors: NORMARK WILLIAM R. , PAULL CHARLES K. , CARESS DAVID W. , USSLER III WILLIAM , SLITER RAY 
Published: March 2009

AbstractErosional and depositional bedforms have been imaged at outcrop scale in the upper Redondo Fan, in the San Pedro Basin of offshore Southern California in ≥600 m water depths, using an Autonomous Underwater Vehicle developed by the Monterey Bay Aquarium Research Institute. The Autonomous Underwater Vehicle is equipped with multibeam and chirp sub‐bottom sonars. Sampling and photographic images using the Monterey Bay Aquarium Research Institute Remotely Operated Vehicle Tiburon provide groundtruth for the Autonomous Underwater Vehicle survey. The 0·3 m vertical and 1·5 m lateral bathymetric resolution and 0·1 m sub‐bottom profile resolution provide unprecedented detail of bedform morphology and structure. Multiple channels within the Redondo Fan have been active at different times during the Late Holocene (0 to 3000 yr bp). The currently active channel extending from Redondo Canyon makes an abrupt 90° turn at the canyon mouth before resuming a south‐easterly course along the east side of the Redondo Fan. This channel is floored by sand and characterized by small steps generally <1 m in relief, spaced 10 to 80 m in the down‐channel direction. A broader channel complex lies along the western side of the fan valley that was last active more than 850 years ago. Two distinct trains of large scours, with widths ranging from tens to a few hundred metres and depths of 20 m, occur on the floor of the western channel complex, which has a thin mud drape. If observed in cross‐section only, these large scours would probably be misidentified as the thalweg of an active channel.
Budding dispersal and the sex ratio
Authors: Gardner A. , Arce A. , Alpedrinha J. 
Published: March 2009

AbstractThere is much interest in understanding how population demography impacts upon social evolution. Here, we consider the impact of rate and pattern of dispersal upon a classic social evolutionary trait – the sex ratio. We recover existing analytical results for individual dispersal, and we extend these to allow for budding dispersal. In particular, while a cancelling of relatedness and kin competition effects means that the sex ratio is unaffected by the rate of individual dispersal, we find that a decoupling of relatedness and kin competition means that budding dispersal favours increasingly female‐biased sex ratios. More generally, our analysis illustrates the relative ease with which biological problems involving class structure can be solved using a kin selection approach to social evolution theory.
Risk Assessment and Withdrawal Behavior by Two Species of Aposematic Poison Frogs, Dendrobates auratus and Oophaga pumilio, on Forest Trails
Authors: Cooper Jr William E. , Caldwell Janalee P. , Vitt Laurie J. 
Published: March 2009

AbstractMany chemically defended prey advertize toxicity to predators by aposematic coloration. When aposematic prey are approached, they often move slowly or not at all, allowing predators to evaluate their unprofitability. Poison frogs (Dendrobatidae) are toxic, aposematically colored, forage openly and diurnally, and are much easier to capture than many palatable frogs. Although protected against diverse predators, they are sometimes attacked and are subjected to injury by large animals without predatory intent. We predicted that they have limited escape behavior, but retain ability to assess and respond to risk. When we approached Dendrobates auratus and Oophaga pumilio on forest trails, both species hopped by the shortest route to the nearer forest edge and stopped there. When approached, D. auratus moved after shorter latency at an angle closer to perpendicular to the forest edge, were more likely to leave the trail, and left the trail sooner with fewer changes in direction after moving a shorter distance than when not approached. In agreement with predictions of optimal escape theory based on risk, flight initiation distance by D. auratus was greater when approached directly than indirectly and rapidly than slowly, and was greater when frogs were in the open than partially concealed. Frogs neither attempted rapid escape nor entered refuges. Both species hopped leisurely and remained visible after stopping. They exhibit the diminished escape behavior of aposematic prey, yet retain the capacity to assess risk and adjust behavior accordingly. Their behavior demonstrates continued need for escape behavior by highly toxic aposematic prey.
Mate Attraction in a Burrowing Wolf‐Spider (Araneae, Lycosidae) is not Olfactory Mediated
Authors: Fernández‐Montraveta Carmen , Cuadrado Mariano 
Published: March 2009

AbstractSpiders are mostly solitary living animals, and males actively search for females by using chemical cues. Compared with the overwhelming evidence demonstrating the role of spider contact sex‐pheromones, support for the role of olfactory sex‐pheromones in spider communication is scarce. In Lycosa tarantula (L., 1758), a Mediterranean burrowing wolf spider inhabiting dry and open habitats and dependent on chemical cues for mate searching, we investigated the role of olfactory sex‐pheromones in mate attraction. We conducted both laboratory and field experiments, using multiple experimental approaches (two‐choice olfactometer in the laboratory and pit‐fall traps and two‐choice open arenas in the field) and controlling for male sexual arousal. Our results support the hypothesis that mate attraction in this species is not olfactory‐mediated. In the two‐choice olfactometer, males did not orient preferentially to the side where the stimulus was concealed. Stimuli did not influence response latency or the relative time spent in the experimental side of the olfactometer. In the field, the effectiveness of experimental pit‐fall traps baited with potential olfactory sex‐pheromones did not differ from that of control traps. In the two‐choice open arenas, males did not show any clear preference for the experimental half containing the potential olfactory sex‐pheromone, nor did they show any sexual response. These results demonstrate that olfactory‐mediated cues are not important during mate attraction in this species, and enforce the idea that habitat preferences and life style might explain the relative role of contact and olfactory‐mediated chemical cues during spider mate searching.
Social Networks and the Formation and Maintenance of River Otter Groups
Authors: Hansen Heidi , McDonald David B. , Groves Pamela , Maier Julie A. K. , Ben‐David Merav 
Published: March 2009

AbstractMany studies have evaluated why male mammals form social groups; few however have investigated how these groups are formed and maintained. We observed behavioral interactions of 15 male river otters (Lontra canadensis) captured in Prince William Sound (PWS), Alaska, and held in captivity for 10 mo. Because the otters were captured in various areas and differed in age and relatedness, we were able to test how kinship and age influenced social interactions. We also explored how kinship, age and social interactions in captivity related to geographic spacing after the otters were released back in PWS. In 284 h of observations, the otters exhibited more positive than negative interactions. Social network models indicated that in the early stage of captivity, there were more links among individuals than in the late stage. In the late‐stage period, older animals that had higher testosterone levels exhibited increased social distance and lower information centrality (a network connectivity metric). Social distance was not related to genetic distance, nor did it relate directly to age, although both social distance and age were correlated with post‐release geographic distance. Thus, the formation of male groups in coastal river otters is largely influenced by familiarity and past experience, rather than kinship. The maintenance of groups, especially during the mating season, is a function of reproductive status and age, with older animals withdrawing from the social network during that time. What other phenotypic characters may contribute to the formation and maintenance of river otter groups merit future exploration.
Immunohistochemical detection of advanced glycation end products in human bladder with specific monoclonal antibody
Authors: Matsumoto Kenshi , Fujiwara Yukio , Nagai Ryoji , Yoshida Masaki 
Published: March 2009

Objective:  To investigate the accumulation of advanced glycation end products (AGE) in human bladder.Methods:  Human bladder specimens were obtained from nine patients during radical cystectomy. Frozen sections were immunohistochemically analyzed by three different monoclonal anti‐AGE antibodies such as anti‐Nε‐(carboxymethyl)lysine (CML), anti‐imidazolone and anti‐pentosidine antibodies. Bladder sections were stained with these antibodies by indirect immunoperoxidase methods. Double immunohistochemical staining with one of the anti‐AGE antibodies or an anti‐human macrophage antibody was also carried out.Results:  We demonstrated that CML and pentosidine were accumulated in human bladder extracellularly as well as intracellularly, whereas any accumulation of imidazolone was not observed. Double immunohistochemical staining indicated that AGE‐accumulated cells in human bladder were derived from macrophages.Conclusions:  The present study demonstrated that AGE‐structures such as CML and pentosidine are accumulated extracellularly in human bladder, and were endocytosed by tissue macrophages.