bluuebunny/crossref_metadata_2025_split huggingface dataset:
The kangaroo conundrum remains
Authors: VIGGERS KAREN L , LINDENMAYER DAVID B 
Published: July 2007

Summary

The management of kangaroo populations is a major land management and conservation issue in many parts of Australia.
Viggers & Hearn (2005) reported the results of a substantial radio‐tracking study of the eastern grey kangaroo (Macropus giganteus Shaw) in south‐eastern Australia. Martin et al. (2007) critique the study design, home range analysis, biomass assessment and other aspects of the work by Viggers & Hearn (2005).
We reject the criticisms made by Martin et al. (2007) and believe that the study design employed by Viggers & Hearn (2005) was sound. The work also was preceded by extensive day and night‐time field assessments to enable contrasts between low and high density M. giganteus populations. We also contend that the home range analysis was not flawed: the methods employed by Viggers & Hearn (2005) were in fact the same ones recommended by Martin et al. (2007). We believe that other criticisms made by Martin et al. (2007) also cannot be sustained.
Synthesis and applications. Viggers & Hearn (2005) found that patches of remnant native vegetation were used as day and night‐time refuges by M. giganteus. This creates a disincentive for farmers to conserve remnant native vegetation. The criticisms by Martin et al. (2007) have no bearing on this conclusion; hence the kangaroo conundrum stands.
The relative effectiveness of practice change interventions in overcoming common barriers to change: a survey of 14 hospitals with experience implementing evidence‐based guidelines
Authors: Simpson Fiona , Doig Gordon S. 
Published: July 2007

AbstractAims and objectives  Changing practice to reflect current best evidence can be costly and time‐consuming. The purpose of this survey was to determine the optimal combination of practice change interventions needed to overcome barriers to practice change commonly encountered in the intensive care unit (ICU).Design  A survey instrument delivered by mail with email follow‐up reminders.Setting  Fourteen hospitals throughout Australia and New Zealand.Subjects  Individuals responsible for implementing an evidence‐based guideline for nutritional support in the ICU.Survey  Practice change interventions were ranked in order of effectiveness and barriers to change were ranked in order of how frequently they were encountered.Results  A response rate of 100% was achieved. Interventions traditionally regarded as strong (academic detailing, active reminders) were ranked higher than those traditionally regarded as moderate (audit and feedback), or weak (posters, mouse mats). The high ranks of the site initiation visit (educational outreach, modest) and in‐servicing (didactic lectures, weak) were unexpected, as was the relatively low rank of educationally influential, peer‐nominated opinion leaders. Four hospitals reported the same doctor‐related barrier as ‘most common’ and the remaining 10 hospitals reported three different doctor‐related barriers, two nursing‐related barriers and three organizational barriers as most common.Conclusions  When designing a multifaceted, multi‐centre change strategy, the selection of individual practice change interventions should be based on: (1) an assessment of available resources; (2) recognition of the importance of different types of barriers to different sites; (3) the potential for combinations of interventions to have a synergistic effect on practice change, and (4) the potential for combinations of interventions to actually reduce workload.
Human influences on rates of phenotypic change in wild animal populations
Authors: HENDRY ANDREW P. , FARRUGIA THOMAS J. , KINNISON MICHAEL T. 
Published: July 2007

AbstractHuman activities can expose populations to dramatic environmental perturbations, which may then precipitate adaptive phenotypic change. We ask whether or not phenotypic changes associated with human‐disturbed (anthropogenic) contexts are greater than those associated with more ‘natural’ contexts. Our meta‐analysis is based on more than 3000 rates of phenotypic change in 68 ‘systems’, each representing a given species in a particular geographical area. We find that rates of phenotypic change are greater in anthropogenic contexts than in natural contexts. This difference may be influenced by phenotypic plasticity — because it was evident for studies of wild‐caught individuals (which integrate both genetic and plastic effects) but not for common‐garden or quantitative genetic studies (which minimize plastic effects). We also find that phenotypic changes in response to disturbance can be remarkably abrupt, perhaps again because of plasticity. In short, humans are an important agent driving phenotypic change in contemporary populations. Although these changes sometimes have a genetic basis, our analyses suggest a particularly important contribution from phenotypic plasticity.
Analysis of the RpoS regulon in Borrelia burgdorferi in response to mammalian host signals provides insight into RpoS function during the enzootic cycle
Authors: Caimano Melissa J. , Iyer Radha , Eggers Christian H. , Gonzalez Cynthia , Morton Elizabeth A. , Gilbert Michael A. , Schwartz Ira , Radolf Justin D. 
Published: July 2007

Summary Borrelia burgdorferi (Bb) adapts to its arthropod and mammalian hosts by altering its transcriptional and antigenic profiles in response to environmental signals associated with each of these milieus. In studies presented here, we provide evidence to suggest that mammalian host signals are important for modulating and maintaining both the positive and negative aspects of mammalian host adaptation mediated by the alternative sigma factor RpoS in Bb. Although considerable overlap was observed between genes induced by RpoS during growth within the mammalian host and following temperature‐shift, comparative microarray analyses demonstrated unequivocally that RpoS‐mediated repression requires mammalian host‐specific signals. A substantial portion of the in vivo RpoS regulon was uniquely upregulated within dialysis membrane chambers, further underscoring the importance of host‐derived environmental stimuli for differential gene expression in Bb. Expression profiling of genes within the RpoS regulon by quantitative reverse transcription polymerase chain reaction (qRT‐PCR) revealed a level of complexity to RpoS‐dependent gene regulation beyond that observed by microarray, including a broad range of expression levels and the presence of genes whose expression is only partially dependent on RpoS. Analysis of Bb‐infected ticks by qRT‐PCR established that expression of rpoS is induced during the nymphal blood meal but not within unfed nymphs or engorged larvae. Together, these data have led us to postulate that RpoS acts as a gatekeeper for the reciprocal regulation of genes involved in the establishment of infection within the mammalian host and the maintenance of spirochetes within the arthropod vector.
Naturally acquired antibodies to polymorphic and conserved epitopes of Plasmodium falciparum merozoite surface protein 3
Authors: OSIER F. H. A. , POLLEY S. D. , MWANGI T. , LOWE B. , CONWAY D. J. , MARSH K. 
Published: July 2007

Summary Many studies on the role of merozoite surface protein 3 (MSP3) in immunity against malaria have focused on a conserved section of MSP3. New evidence suggests that polymorphic sequences within MSP3 are under immune selection. We report a detailed analysis of naturally‐acquired antibodies to allele‐specific and conserved parts of MSP3 in a Kenyan cohort. Indirect and competition ELISA to heterologous recombinant MSP3 proteins were used for antibody assays, and parasites were genotyped for msp3 alleles. Antibody reactivity to allele‐specific and conserved epitopes of MSP3 was heterogenous between individuals. Overall, the prevalence of allele‐specific antibody reactivity was significantly higher (3D7‐specific 54%, K1‐specific 41%) than that to a recombinant protein representing a conserved portion of C‐terminal MSP3 (24%, P < 0·01). The most abundant IgG subclass was IgG3, followed by IgG1. Allele‐specific reactivity to the K1‐type of MSP3 was associated with a lower risk of clinical malaria episodes during a 6‐month follow‐up in individuals who were parasitized at the start of the malaria transmission season (Relative risk 0·41 with 95% confidence interval 0·20–0·81, P = 0·011). The potential importance of allele‐specific immunity to MSP3 should be considered in addition to immunity to conserved epitopes, in the development of an MSP3 malaria vaccine.
Selective detection of Pseudomonas syringae pv. tomato using dot blot hybridization and real‐time PCR
Authors: Fanelli V. , Cariddi C. , Finetti‐Sialer M. 
Published: July 2007

Two rapid detection methods based on dot blot hybridization with a nonradioactive DNA probe and molecular beacon‐PCR were developed for the specific detection of Pseudomonas syringae pv. tomato, the causal agent of bacterial speck of tomato. A 1378 bp DNA fragment (Acc. No. AM039892), obtained from the extension of a 255 bp fragment generated by a RAPD protocol, was used to find a suitable combination of primers specific for the tomato pathovar. A 138 bp fragment from the genome of P. syringae pv. tomato DC 3000 was used as DNA probe. In dot blots of DNA extracted from either pure cultures or artificially contaminated seeds washes, the probe recognized specifically the tomato pathovar. A molecular beacon was designed from the same region for the specific detection and quantification of P. syringae pv. tomato by real‐time PCR. A highly significant correlation was observed between the amount of target DNA and the cycle threshold (Ct). Using a fast protocol for DNA extraction, from pure cultures and from washes of artificially contaminated seeds, the limit of detection was about 1 × 102 CFU. The diagnostic tools developed proved highly specific for P. syringae pv. tomato and simple to use. They can therefore be applied to large‐scale testing of tomato seeds and seedlings for the assessment of their phytosanitary condition in nurseries.
A green fluorescent protein‐based screening method for identification of resistance in anthurium to systemic infection by Xanthomonas axonopodis pv. dieffenbachiae
Authors: Elibox W. , Umaharan P. 
Published: July 2007

Resistance of cultivars of Anthurium andraeanum to systemic infection by Xanthomonas axonopodis pv. dieffenbachiae, the causal organism of bacterial blight disease of anthurium, was investigated using a bioengineered bacterial strain containing p519ngfp plasmid. Successful infection establishment in anthurium was found to be cultivar and inoculum density dependent, but independent of plant age. Injection of cut petioles (stage‐2 leaf) with 100 µL inoculum (109 CFU mL−1) resulted in 100% infection establishment in susceptible cultivars on a repeatable basis, and differentiated between various levels of observed field resistance. Time to death (weeks) and proportion of dead plants best differentiated between levels of resistance and cultivars were placed in four groups based on these criteria. The susceptible group (32 cultivars) rapidly declined within 6–12 weeks of inoculation (WAI) and resulted in 100% plant death; the moderately resistant group (10 cultivars) declined within 12 WAI, but resulted in less than 100% plant death; the resistant category had less than 100% plant death with a slow decline taking over 20 weeks; and the highly resistant category (15 cultivars) showed 0% infection. The correlation coefficient between green fluorescent protein (GFP)‐fluorescence and eventual death of plants was 0·90, indicating that the final death of individual plants can be reasonably well predicted based on GFP‐fluorescence data at 5 WAI. Hence GFP data at 5 WAI can be used for early detection of latently infected plants and may assist screening for resistance in segregating populations of anthurium.
Effect of temperature and duration of wetness during initial infection periods on disease development, fungal biomass and mycotoxin concentrations on wheat inoculated with single, or combinations of, Fusarium species
Authors: Xu X.‐M. , Monger W. , Ritieni A. , Nicholson P. 
Published: July 2007

Experiments were conducted under controlled environment conditions to study the relationship between environmental conditions, development of fusarium head blight (FHB) and mycotoxin production. A single isolate from each of four Fusarium species (F. avenaceum, F. culmorum, F. graminearum and F. poae) was used to inoculate wheat ears separately. Combinations of two or three isolates were also used to inoculate ears simultaneously. Inoculated ears were subjected to various combinations of duration of wetness (6–48 h) and temperature (10–30°C). For all inoculations, both incidence of spikelets with FHB symptoms and concentration of mycotoxins generally increased with increasing length of wetness period and temperature. There were significant positive correlations among disease incidence, fungal biomass (quantified as total amount of fungal DNA) and mycotoxins. Mycotoxin production was also greatly enhanced by high temperatures (≥ 20°C) during initial infection periods. In single‐isolate inoculations, F. poae was the least aggressive. There was no evidence to support synergetic interactions between fungal isolates in causing visual symptoms; rather the results suggest, in most cases, the presence of competitive interactions. Furthermore, the competition led to large reductions in fungal biomass compared to single‐isolate inoculations, often > 90% reduction for the weaker isolate(s). In contrast, mycotoxin productivity increased dramatically in the co‐inoculations, by as much as 1000 times, suggesting that competition resulted in greater production of trichothecene mycotoxins. The F. graminearum isolate was most competitive and isolates of the other three species were similar in their competitiveness.
Habitat‐dependent geographical variation in ontogenetic allometry of the shiner perch Cymatogaster aggregata Gibbons (Teleostei: Embiotocidae)
Authors: WOODS P. J. 
Published: July 2007

AbstractStudies of intraspecific morphological variation in fishes have traditionally focused on freshwater rather than marine species. In addition, such studies typically focus on adults, although causes and intensities of selective pressures most likely vary through an individual's lifetime. In this study, body and head shape of a marine species, shiner perch Cymatogaster aggregata Gibbons were compared among localities along the Pacific Northwest coast of North America. Evidence was found for intraspecific variation in ontogenetic allometry, and for a closer correlation of body shape with environment rather than geographical proximity. This correlation with environment was more evident in younger fish, thereby demonstrating the importance of analysing multiple life stages. A common garden experiment suggests both environmental and genetic bases for the observed differences. Recognizing intraspecific ecomorphological complexity and its specificity to habitat and/or life stage can have important consequences for understanding the role of local adaptation and population dynamics in macroecology.
Evolutionary diversification of clades of squamate reptiles
Authors: RICKLEFS R. E. , LOSOS J. B. , TOWNSEND T. M. 
Published: July 2007

AbstractWe analysed the diversification of squamate reptiles (7488 species) based on a new molecular phylogeny, and compared the results to similar estimates for passerine birds (5712 species). The number of species in each of 36 squamate lineages showed no evidence of phylogenetic conservatism. Compared with a random speciation–extinction process with parameters estimated from the size distribution of clades, the alethinophidian snakes (2600 species) were larger than expected and 13 clades, each having fewer than 20 species, were smaller than expected, indicating rate heterogeneity. From a lineage‐through‐time plot, we estimated that a provisional rate of lineage extinction (0.66 per Myr) was 94% of the rate of lineage splitting (0.70 per Myr). Diversification in squamate lineages was independent of their stem age, but strongly related to the area of the region within which they occur. Tropical vs. temperate latitude exerted a marginally significant influence on species richness. In comparison with passerine birds, squamates share several clade features, including: (1) independence of species richness and age; (2) lack of phylogenetic signal with respect to clade size; (3) general absence of exceptionally large clades; (4) over‐representation of small clades; (5) influence of region size on clade size; and (6) similar rates of speciation and extinction. The evidence for both groups suggests that clade size has achieved long‐term equilibrium, suggesting negative feedback of species richness on the rate of diversification.
Male choice generates stabilizing sexual selection on a female fecundity correlate
Authors: CHENOWETH S. F. , PETFIELD D. , DOUGHTY P. , BLOWS M. W. 
Published: July 2007

AbstractWe know very little about male mating preferences and how they influence the evolution of female traits. Theory predicts that males may benefit from choosing females on the basis of traits that indicate their fecundity. Here, we explore sexual selection generated by male choice on two components of female body size (wing length and body mass) in Drosophila serrata. Using a dietary manipulation to alter female size and 828 male mate choice trials, we analysed linear and nonlinear sexual selection gradients on female mass and wing length. In contrast to theoretical expectations and prevailing empirical data, males exerted stabilizing rather than directional sexual selection on female body mass, a correlate of fecundity. Sexual selection was detected only among females with access to standard resource levels as an adult, with no evidence for sexual selection among resource‐depleted females. Thus the mating success of females with the same body mass differed depending upon their access to resources as an adult. This suggests that males in this species may rely on signal traits to assess body mass rather than assessing it directly. Stabilizing rather than directional sexual selection on body mass together with recent evidence for stabilizing sexual selection on candidate signal traits in this species suggests that females may trade‐off resources allocated to reproduction and sexual signalling.
Phylogenetic analysis of floral integration inSchizanthus(Solanaceae): does pollination truly integrate corolla traits?
Authors: PÉREZ F. , ARROYO M. T. K. , MEDEL R. 
Published: July 2007

AbstractTo assess whether floral integration patterns result from the action of pollinator selection on functionally related traits, we compared corolla integration patterns in eightSchizanthusspecies differing in pollination systems and in their degree of pollinator dependence across a molecular phylogeny. Integration patterns differed among species and these differences were not related to their phylogenetic relatedness. When the putative original function of some corolla traits was lost in pollinator‐dependent species, the integration among nonfunctional characters and the rest of the corolla traits was disrupted. This pattern was not presented in species adapted for late autonomous selfing, which exhibited higher corolla integration than their pollinator‐dependent relatives. These results suggest that corolla integration in pollinator‐dependent species was shaped by pollinator‐mediated selection. Decoupling of nonfunctional traits in these species may result from a relaxation of correlational selection or from selection acting against a default covariation provided by genetic and developmental connections.
Social semantics: toward a genuine pluralism in the study of social behaviour
Authors: WILSON D. S. 
Published: July 2007

AbstractPluralism is the coexistence of equivalent theoretical frameworks, either because they are historically entrenched or because they achieve separate insights by viewing the same process in different ways. A recent article by West et al. [Journal of Evolutionary Biology (2007) vol. 20, 415–432] attempts to classify the many equivalent frameworks that have been developed to study the evolution of social behaviour. This article addresses shortcomings in the West et al.’s article, especially with respect to multilevel selection, in a common effort to maximize the benefits of pluralism while minimizing the semantic costs.
Mate Change Reduces the Reproductive Rate of Males in a Monogamous Pipefish Corythoichthys haematopterus: The Benefit of Long‐Term Pair Bonding
Authors: Sogabe Atsushi , Matsumoto Koji , Yanagisawa Yasunobu 
Published: July 2007

AbstractMonogamy has evolved independently in many taxa, and often involves biparental care of the young and/or low defendability of multiple mates. In many teleost fishes, however, strict monogamy is practised without such limitations. In this study, we examined why males of the pipefish Corythoichthys haematopterus (family: Syngnathidae) reproduce monogamously without changing to another mate. For this we examined the time cost associated with mate change by experimentally removing females from mating pairs and compelling the males to change mates. Mate‐changing males needed longer interspawning intervals, an average of 8.5 d, than their monogamous counterparts, which was primarily because of the time needed for the new female to prepare mature eggs. As a result, we assume that mate change entails considerable reproductive costs associated with a decrease in reproductive rate. Monogamy and long‐term pair bonding in C. haematopterus are likely maintained because of high reproductive rates by repeatedly reproducing with the same mate over a lifetime.
Sexual Differences in the Behavioral Response of Túngara Frogs, Physalaemus pustulosus, to Cues Associated with Increased Predation Risk
Authors: Bernal Ximena E. , Stanley Rand A. , Ryan Michael J. 
Published: July 2007

AbstractEngaging in mating behaviors usually increases exposure to predators for both males and females. Anti‐predator strategies during reproduction may have important fitness consequences for prey. Previous studies have shown that individuals of several species adjust their reproductive behavior according to their assessment of predation risk, but few studies have explored potential sexual differences in these strategies. In this study, we investigate whether the acoustic cues associated with predatory attacks or those associated with predators themselves affect the mating behavior of female and male túngara frogs, Physalaemus pustulosus. We compared the responses of females approaching a mate and those of calling males when exposed to mating calls associated with sounds representing increased hazard. When presented with mating calls that differed only in whether or not they were followed by a predation‐related sound, females preferentially approached the call without predation‐related sounds. In contrast to females, calling males showed greater vocal response to calls associated with increased risk than to a call by itself. We found significant differences in the responses of females and males to several sounds associated with increased hazard. Females behaved more cautiously than males, suggesting that the sexes balance the risk of predation and the cost of cautious mating strategies differently.