bluuebunny/crossref_metadata_2025_split huggingface dataset:
The mystery of the missing toes: extreme levels of natural mutilation in island lizard populations
Authors: Vervust Bart , Van Dongen Stefan , Grbac Irena , Van Damme Raoul 
Published: June 2009

Summary 1. Ecological interactions that involve aggressive confrontations between animals are important in shaping the evolution of morphology, behaviour and life history. However, as such confrontations are rarely witnessed, direct quantification of the intensity of these processes in natural populations is notoriously difficult. While the utilization of the frequency of non‐lethal injuries is fraught with difficulties, it may provide information concerning different types of interaction, such as predation, intraspecific aggression and interspecific interference competition. 2. In this paper, we report on an exceptionally large difference in toe loss incidence between two populations of Podarcis sicula lizards living on small, neighbouring islands in the Adriatic Sea. We caught 900 lizards and recorded the number and location of missing toes. Subsequently, we investigated five non‐mutually exclusive hypotheses concerning differences in bite force capacity, bone strength, predation intensity, average age and intraspecific aggression that may provide proximate explanations for the observed differences in injury frequencies. 3. Bite force differences differed considerably between the populations, but bone strength was found to be stronger in the populations with a higher frequency of natural scars. Predation pressure clearly differed between the populations, but we found higher injury rates under predation relaxation. 4. Our results indicate that density and consequently an increased intraspecific competition is the most likely explanation for the observed high frequencies of injuries. We suggest that the intensity of toe amputation between lizard populations may be a useable indirect indication for the intensity of intraspecific competition. 5. This study shows how a combination of morphological, physiological, behavioural and ecological measurements can be used to test assumptions implicit to alternative explanations of an observed phenomenon. Such tests can reveal how likely each of these explanations is, even if the processes leading to the phenomenon are difficult to observe directly.
Diet predicts intestine length in Lake Tanganyika’s cichlid fishes
Authors: Wagner Catherine E. , McIntyre Peter B. , Buels Kalmia S. , Gilbert Danielle M. , Michel Ellinor 
Published: June 2009

Summary
1.
Among vertebrates, herbivores have longer digestive tracts than animals at higher trophic levels, a pattern thought to reflect a trade‐off between digestive efficiency and tissue maintenance costs. However, phylogenetic influences on this pattern have rarely been considered. Taxa that have undergone diversification accompanied by dietary shifts provide a powerful opportunity to examine the relationship between diet and intestine length while accounting for phylogeny.
2.
In this paper we assess the relationship between diet and intestine length in the cichlid fishes of Lake Tanganyika, which are renowned for their diversity of species and trophic strategies.
3.
First, we test the effect of trophic position on intestine length across 32 species, while controlling for phylogeny. Trophic position was inferred from nitrogen stable isotopes, which provide a temporally integrated, quantitative perspective on the complex diets of tropical fish. Second, we examine patterns of intraspecific variation in intestine length of an algivorous cichlid (Tropheus brichardi) along a natural spatial gradient in algal nitrogen content.
4.
Trophic position explains 51% of size‐standardized variation in intestine length after accounting for phylogeny. Accounting for phylogeny does not substantially alter the relationship between trophic position and intestine length, despite the existence of phylogenetic signal in both traits. Thus, diet is a strong predictor of variation at the interspecific level.
5.
There is a striking inverse relationship between intestine length and algal nutrient content among populations of T. brichardi, suggesting substantial plasticity in response to food quality, and thus a strong dietary influence on patterns of intraspecific variation.
6.
Diet is a strong predictor of intestine length at both intra‐ and interspecific scales, indicating that fish adjust their phenotype to balance nutritional needs against energetic costs. Furthermore, functional explanations for trophic diversification of cichlid fishes in the African Great Lakes have long focused on jaw structures, but our results indicate that intestinal plasticity in response to diet quality may also be an important mechanism for accommodating trophic shifts during evolutionary radiations.
Development of a multiplex PCR assay for Photobacterium damselae subsp. piscicida identification in fish samples
Authors: Amagliani G , Omiccioli E , Andreoni F , Boiani R , Bianconi I , Zaccone R , Mancuso M , Magnani M 
Published: June 2009

AbstractA multiplex polymerase chain reaction protocol for the detection of Photobacterium damselae and subspecies piscicida and damselae discrimination, with internal amplification control, was developed. Assay specificity was assessed by testing 19 target and 25 non‐target pure cultures. The detection limit was 500 fg, corresponding to 100 genome equivalents. The optimized protocol was also prevalidated with spleen, kidney and blood samples from infected and uninfected sea bass, without any culture step, and it can be proposed as a valid alternative to culture standard methods for the rapid and specific diagnosis of photobacteriosis in fish.
Tissue tropism of nervous necrosis virus (NNV) in Atlantic cod, Gadus morhua L., after intraperitoneal challenge with a virus isolate from diseased Atlantic halibut, Hippoglossus hippoglossus (L.)
Authors: Korsnes K , Karlsbakk E , Devold M , Nerland A H , Nylund A 
Published: June 2009

AbstractAtlantic cod, Gadus morhua, averaging 100 g, were experimentally challenged by intraperitoneal injection of nervous necrosis virus (NNV) originating from Atlantic halibut. Cod tissues, including blood, gill, pectoral fin, barbel, ventricle, atrium, spleen, liver, lateral line (including muscle tissue), eye (retina) and brain, were sampled at day 25 and 130 and investigated by real‐time RT‐PCR for the presence of NNV. Relative quantifications at day 130 were calculated using the 2−ΔΔCt method. Immunosuppression by injection of prednisolone‐acetate was introduced for a 30‐day period, and tissue sampled at day 180 and relative quantification estimated. No mortality or clinical signs of disease were observed in the challenged group. The challenge resulted in detection of NNV in blood, spleen, kidney, liver, heart atrium and heart ventricle at day 25, and by the end of the experiment NNV showed a clear increase in brain and retina, suggesting these to be the primary tissues for viral replication. There was no increase in the relative amount of NNV in blood, atrium, ventricle, spleen, liver and kidney. Corticosteroid implants resulted in a weak increase in virus RNA in spleen, kidney, liver and brain. These findings suggest that Atlantic cod is susceptible to infection with NNV from halibut. The observed tissue tropism patterns suggest an initial viraemic phase, followed by neurotrophy. Head‐kidney is the best tissue identified for possible NNV detection by non‐lethal biopsy, but detection was not possible in all injected fish.
Outbreak of betanodavirus infection in tilapia, Oreochromis niloticus (L.), in fresh water
Authors: Bigarré L , Cabon J , Baud M , Heimann M , Body A , Lieffrig F , Castric J 
Published: June 2009

AbstractA betanodavirus associated with a massive mortality was isolated from larvae of tilapia, Oreochromis niloticus, maintained in fresh water at 30 °C. Histopathology revealed vacuolation of the nervous system, suggesting an infection by a betanodavirus. The virus was identified by indirect fluorescent antibody test in the SSN1 cell line and further characterized by sequencing of a PCR product. Sequencing of the T4 region of the coat protein gene indicated a phylogenetic clustering of this isolate within the red‐spotted grouper nervous necrosis virus type. However, the tilapia isolate formed a unique branch distinct from other betanodavirus isolates. The disease was experimentally reproduced by bath infection of young tilapia at 30 °C. The reservoir of virus at the origin of the outbreak remains unidentified. To our knowledge, this is the first report of natural nodavirus infection in tilapia reared in fresh water.
Geographical variation in genetic structure of an Atlantic Coastal Forest frog reveals regional differences in habitat stability
Authors: FITZPATRICK SARAH W. , BRASILEIRO CINTHIA A. , HADDAD CÉLIO F. B. , ZAMUDIO KELLY R. 
Published: June 2009

AbstractClimatic oscillations throughout the Pleistocene combined with geological and topographic complexity resulted in extreme habitat heterogeneity along the Atlantic coast of Brazil. Inferring how these historic landscape patterns have structured the current diversity of the region's biota is important both for our understanding of the factors promoting diversification, as well as the conservation of this biodiversity hotspot. Here we evaluate potential historical scenarios of diversification in the Atlantic Coastal Forest of Brazil by investigating the population genetic structure of a frog endemic to the region. Using mitochondrial and nuclear sequences, we generated a Bayesian population‐level phylogeny of theThoropa miliarisspecies complex. We found deep genetic divergences among five geographically distinct clades. Southern clades were monophyletic and nested within paraphyletic northern clades. Analyses of historical demographic patterns suggest an overall north to south population expansion, likely associated with regional differences in habitat stability during the Pliocene and early Pleistocene. However, genetic structure among southern populations is less pronounced and likely represents more recent vicariant events resulting from Holocenic sea‐level oscillations. Our analyses corroborate that the Atlantic Coastal Forest has been a biogeographically dynamic landscape and suggest that the high diversity of its fauna and flora resulted from a combination of climatic and geologic events from the Pliocene to the present.
Contrasting patterns of genetic diversity at three different genetic markers in a marine mammal metapopulation
Authors: HOFFMAN J. I. , DASMAHAPATRA K. K. , AMOS W. , PHILLIPS C. D. , GELATT T. S. , BICKHAM J. W. 
Published: June 2009

AbstractMany studies use genetic markers to explore population structure and variability within species. However, only a minority use more than one type of marker and, despite increasing evidence of a link between heterozygosity and individual fitness, few ask whether diversity correlates with population trajectory. To address these issues, we analysed data from the Steller's sea lion, Eumetiopias jubatus, where three stocks are distributed over a vast geographical range and where both genetic samples and detailed demographic data have been collected from many diverse breeding colonies. To previously published mitochondrial DNA (mtDNA) and microsatellite data sets, we have added new data for amplified fragment length polymorphism (AFLP) markers, comprising 238 loci scored in 285 sea lions sampled from 23 natal rookeries. Genotypic diversity was low relative to most vertebrates, with only 37 loci (15.5%) being polymorphic. Moreover, contrasting geographical patterns of genetic diversity were found at the three markers, with Nei's gene diversity tending to be higher for AFLPs and microsatellites in rookeries of the western and Asian stocks, while the highest mtDNA values were found in the eastern stock. Overall, and despite strongly contrasting demographic histories, after applying phylogenetic correction we found little correlation between genetic diversity and either colony size or demography. In contrast, we were able to show a highly significant positive relationship between AFLP diversity and current population size across a range of pinniped species, even though equivalent analyses did not reveal significant trends for either microsatellites or mtDNA.
A quantitative review of heterozygosity–fitness correlations in animal populations
Authors: CHAPMAN J. R. , NAKAGAWA S. , COLTMAN D. W. , SLATE J. , SHELDON B. C. 
Published: June 2009

AbstractThe ease of obtaining genotypic data from wild populations has renewed interest in the relationship between individual genetic diversity and fitness‐related traits (heterozygosity–fitness correlations, or HFC). Here we present a comprehensive meta‐analysis of HFC studies using powerful multivariate techniques which account for nonindependence of data. We compare these findings with those from univariate techniques, and test the influence of a range of factors hypothesized to influence the strength of HFCs. We found small but significantly positive effect sizes for life‐history, morphological, and physiological traits; while theory predicts higher mean effect sizes for life‐history traits, effect size did not differ consistently with trait type. Newly proposed measures of variation were no more powerful at detecting relationships than multilocus heterozygosity, and populations predicted to have elevated inbreeding variance did not exhibit higher mean effect sizes. Finally, we found evidence for publication bias, with studies reporting weak, nonsignificant effects being under‐represented in the literature. In general, our review shows that HFC studies do not generally reveal patterns predicted by population genetic theory, and are of small effect (less than 1% of the variance in phenotypic characters explained). Future studies should use more genetic marker data and utilize sampling designs that shed more light on the biological mechanisms that may modulate the strength of association, for example by contrasting the strength of HFCs in mainland and island populations of the same species, investigating the role of environmental stress, or by considering how selection has shaped the traits under investigation.
Genetic structure and population dynamics of a heteroecious plant pathogenMelampsora larici‐epiteain short‐rotation coppice willow plantations
Authors: BAYON CARLOS , PEI MING H. , RUIZ CARMEN , HUNTER TOM , KARP ANGELA , TUBBY IAN 
Published: June 2009

AbstractComplex life strategies are common among plant pathogens belonging to rust fungi (Uredinales). The heteroecious willow rustMelampsora larici‐epiteaproduces five spore stages and alternates on larch (Larix). To shed light on the epidemiology of this pathogen, amplified fragment length polymorphisms (AFLPs) were used to determine the genetic diversity and genetic structure of rust samples collected from coppice willow (Salix) plantations at three UK sites (LA, CA and MC) over three sampling dates (September 2000, July 2001 and September 2001). Of the total of 819 isolates, 465 were unique AFLP phenotypes and there was a shift in genotype diversity between the two seasons (0.67 in 2000 and 0.87–0.89 in 2001). No phenotypes were common between the two seasons within a site, suggesting that the rust did not overwinter as an asexual stage within plantations. A temporal analysis detected large amounts of genetic drift (FS = 0.15–0.26) between the two seasons and very small effective population sizes (Ne = 2–3) within sites. These results all point to a new colonization of the plantations by the rust in the second season (2001). TheFST‐analogue values were ΦCT = 0.121, Weir and Cockerham’s θ = 0.086 and the Bayesian estimate θB = 0.087–0.096. The results suggest that the sources of inoculum were somewhat localized and the same sources were mainly responsible for disease epidemics in LA and CA over the two seasons. The relatively lowFST‐values among sites (0.055–0.13) suggest the existence of significant gene flow among the three sampled sites.
Fractal characterisation of plant canopies and application in spray retention modelling for arable crops and weeds
Authors: PATHAN A K , KIMBERLEY M O , FORSTER W A , HASLETT M R , STEELE K D 
Published: June 2009

SummaryFractal analysis can provide a unique mathematical tool to quantify the geometry of irregular and complex plant canopies. This study demonstrated that a single numerical fractal dimension (FD) value derived from an image taken from above the plant canopy could differentiate between and rank the canopies of a range of plant species. We also investigated the influence of canopy architecture and surface characteristics on spray retention. Multiple regressions were used to derive mathematical relationships and develop a spray retention model. It was discovered that the FD value can successfully be used to replace the statistically generated plant morphological factor (Mp4) used in a previous retention model, with the major advantage being that the retention model now only involves variables that can be readily measured. There is an excellent relationship (R2 = 0.99) between actual spray retention per plant (μL) and that predicted by the model incorporating the FD. The spray retentiveness of the plant species studied was ranked using a numerical index based on plant canopy architecture and surface characteristics.
HLA haplotypes and birth weight variation: is your future going to be light or heavy?
Authors: Capittini C. , Pasi A. , Bergamaschi P. , Tinelli C. , De Silvestri A. , Mercati M. P. , Badulli C. , Garlaschelli F. , Sbarsi I. , Guarene M. , Martinetti M. , Salvaneschi L. , Cuccia M. 
Published: June 2009

AbstractBirth weight is known to be a direct indicator of perinatal mortality and a clear predictor of adult pathologies too. It has been correlated with several causes of mortality in adulthood: low birth weight with diabetes, nephropathy and cardiovascular diseases and high birth weight with autoimmune diseases and cancer. In genome‐wide studies, an extended human leucocyte antigen (HLA) region has been linked to birth weight variation. We focused our attention on the HLA haplotypes marked by HLA‐A, HLA‐B and HLA‐DRB1 polymorphisms in 1206 healthy Caucasian newborns belonging to the Cord Blood Bank of Pavia (Italy) and their mothers, aiming to investigate the association between this restricted HLA region and birth weight variation. In our study, the HLA‐B*38;DRB1*13 haplotype showed an ascending trend among centiles addressing to the high foetal weight. The HLA‐A*02;B*15 haplotype showed a descending trend among centiles addressing to the low foetal weight. Besides the acknowledged correlation between the HLA‐A*02 and HLA‐B*15 alleles (as well as low birth weight) and type I diabetes and between the HLA‐B*38 and HLA‐DRB1*13 alleles (as well as high birth weight) and several autoimmune diseases, we cannot predict if our babies, healthy at birth, will suffer from these pathologies during life. Nevertheless, our data point to the HLA telomeric end for markers linked to the low birth weight and to the HLA centromeric end for markers linked to the high birth weight, thus limiting the region involved in birth weight variation, which still represents a useful predictor of disease risk in adulthood.
Divergence in host use ability of a marine herbivore from two habitat types
Authors: VESAKOSKI O. , RAUTANEN J. , JORMALAINEN V. , RAMSAY T. 
Published: June 2009

AbstractWe studied ecological divergence of host use ability in a generalist marine herbivore living in two distinct host plant assemblages. We collectedIdotea balthicaisopods from three populations dominated by the brown algaFucus vesiculosusand three dominated by the seagrassZostera marina. In two reciprocal common garden feeding experiments for adult and laboratory‐born juvenile isopods, we found that isopods from both assemblages performed better with their sympatric dominant host species than did isopods allopatric to this host. This indicates parallel divergence of populations according to the sympatric host plant assemblage. Furthermore, initial body size and body size‐dependent mortality differed between populations from the two assemblages. In nature, this may result in lower fitness of immigrants compared with that of residents and consequently reinforce divergence of the populations. Finally, we discuss how phenotypic plasticity and maternal and random effects may associate with the results.
Compatibility of codling moths Cydia pomonella (Linnaeus) (Lepidoptera: Tortricidae) from South Africa with codling moths shipped from Canada
Authors: Bloem S. , Carpenter J. E. , Blomefield T. L. , Harrison C. 
Published: June 2009

AbstractThe sterile insect technique (SIT) has been successfully applied against codling moth Cydia pomonella (Linnaeus) (Lepidoptera; Tortricidae) in British Columbia since 1992 where the mass‐rearing facility produces between 15 and 16 million moths per week. Due to the seasonality of this pest, the facility is only fully utilized for part of the year. The time and expense of implementing SIT against codling moth in South Africa may be substantially reduced if moths from Canada were sexually compatible with those from South Africa. In addition, because the pome fruit‐growing season in both countries is opposite, the programme in Canada might benefit by maintaining moth production year‐round and selling moths to South Africa. Semi‐field studies in small cages and release‐recapture studies were conducted in an unsprayed apple orchard in South Africa to assess mating compatibility of laboratory‐reared codling moth from Canada and wild codling moths from South Africa. The results suggest that Canadian codling moth males were equally attracted to calling Canadian and South African females despite the fact that Canadian moths had been transported (from Canada to South Africa) for 48 h as both pupae and adults. The data also suggest that at lower field temperatures Canadian moths were more active than South African moths. Results from the release‐recapture field trials indicated that Canadian and South African males were equally attracted to Canadian and South African females. These results suggest that codling moths from Canada and South Africa are fully compatible and indicate that Canadian moths can be used for SIT studies in South Africa. As these studies were conducted with moths from two very different climatic and time zones, it is proposed that populations of codling moth in other pome fruit production areas may also be compatible with the Canadian moths.
Cytological and molecular characterization of a new cytoplasmic male sterility in rapeseed
Authors: Wei W. L. , Wang H. Z. , Liu G. H. 
Published: June 2009

AbstractIt is very important for rapeseed hybrid production to develop and utilize a novel cytoplasmic male sterility (CMS) system concerning the possible risk because of a narrow cytoplasm background. Here the anatomy of anther development in the CMS system, named NCa, was observed using light microscope and transmission electron microscope, and the restriction fragment length polymorphism (RFLP) analyses of mitochondrial DNA of NCa sterile line were also performed in comparison with the other rapeseed sterile lines, such as pol, nap, ogura, and tour. The anther abortion of this CMS line occurred at the later uninucleate microspore stage, and the anatomic aborting characteristics were obviously different from all the other rapeseed CMS lines reported before. The RFLP analyses revealed that five probe/enzyme combinations could distinguish the five CMS lines. The results of anatomic observations and mitochondrial DNA polymorphism indicated that the NCa CMS system is a novel one which differs from the pol, nap, ogura, and tour systems.