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Phenetic and genetic structure of tsetse fly populations (Glossina palpalis palpalis) in southern Ivory Coast  [cached]
Kaba Dramane,Ravel Sophie,Acapovi-Yao Geneviève,Solano Philippe
Parasites & Vectors , 2012, DOI: 10.1186/1756-3305-5-153
Abstract: Background Sleeping sickness, transmitted by G. p. palpalis, is known to be present in the Ivory Coast. G. p. palpalis has recently been reported to occur in several places within the town of Abidjan, including: (i) the Banco forest, (ii) the Abobo Adjamé University campus and (iii) the zoological park. Could these three places be treated sequentially, as separate tsetse populations, or should they be taken as one area comprising a single, panmictic population? Methods The amount of gene flow between these places provides strategic information for vector control. It was estimated by the use of both microsatellite DNA and morphometric markers. The idea was to assess the interest of the faster and much less expensive morphometric approach in providing relevant information about population structure. Thus, to detect possible lack of insect exchange between these neighbouring areas of Abidjan, we used both genetic (microsatellite DNA) and phenetic (geometric morphometrics) markers on the same specimens. Using these same markers, we also compared these samples with specimens from a more distant area of south Ivory Coast, the region of Aniassué (186 km north from Abidjan). Results Neither genetic nor phenetic markers detected significant differentiation between the three Abidjan G. p. palpalis samples. Thus, the null hypothesis of a single panmictic population within the city of Abidjan could not be rejected, suggesting the control strategy should not consider them separately. The markers were also in agreement when comparing G. p. palpalis from Abidjan with those of Aniassué, showing significant divergence between the two sites. Conclusions Both markers suggested that a successful control of tsetse in Abidjan would require the three Abidjan sites to be considered together, either by deploying control measures simultaneously in all three sites, or by a continuous progression of interventions following for instance the "rolling carpet" principle. To compare the geometry of wing venation of tsetse flies is a cheap and fast technique. Agreement with the microsatellite approach highlights its potential for rapid assessment of population structure.
Genetic divergence among geographical populations of the migratory locust in China
Minzhao Zhang,Le Kang
Science China Life Sciences , 2005, DOI: 10.1360/062004-103
Abstract: The random amplified polymorphic DNA (RAPD) technique was used to examine genetic divergence and interrelations of 11 geographical populations of the migratory locust in China, and the role of spatial separation in the population differentiations. AMOVA analysis of genetic variations in all the populations indicated greater within- (79.55%) than among-population variability (20.45%), and that there were significant differentiations among the populations; 11 populations were divided into four regional groups, with significantly greater variability within (82.99%) than among the groups (17.01%), and there existed apparent regional differentiations. Paired comparisons showed significantly greater variability within-than between-groups, indicating significant differentiations between populations of different regional groups. Of all the pairwise comparisons, Hainan and Tibetan groups displayed the greatest differentiation, with the difference between the two groups being seven folds of that between populations within the groups; the least differentiations were exhibited between the groups of Hainan, Xinjiang, and Inner Mongolia, with the differences between groups being only half of the differences between populations within the groups. Mantel tests of the genetic and spatial distances showed that the two matrices were significantly correlated (p<0.01), indicating that the geographical isolation played an important role in the differentiations of the geographical populations of the migratory locusts. Cluster analysis divided all populations into four major groups: Xinjiang and Inner Mongolia group, the Great Plains of North China (the Yellow River and Huai River Plains) group, Hainan group, and Tibet group. Principal component analysis (PCA) supported the division of populations based on the cluster analysis. However, analysis of individuals clustered the locusts into five populations: Xinjiang and Inner Mongolia, Hami in Xinjiang, the Great Plains of North China, Hainan, and Tibet. The locust populations in eastern China displayed apparently continous and gradient variations; as such authors consider that there were no necessity and valid reasons for further division of subspecies. The subspecific status for the main geographical populations of the migratory locusts in China was discussed.
Genetic divergence among geographical populations of the migratory locust in China
ZHANG Minzhao,KANG Le,
ZHANG Minzhao & KANG Le State Key Laboratory of Integrated Management of Pest Insects and Rodents
,Institute of Zoology,Chinese Academy of Sci-ences,Beijing,China

中国科学C辑(英文版) , 2005,
Abstract: The random amplified polymorphic DNA (RAPD) technique was used to examine genetic divergence and interrelations of 11 geographical populations of the migratory locust in China, and the role of spatial separation in the population differentiations. AMOVA analysis of genetic variations in all the populations indicated greater within- (79.55%) than among-population variability (20.45%), and that there were significant differentiations among the populations; 11 populations were divided into four regional groups, with significantly greater variability within (82.99%) than among the groups (17.01%), and there existed apparent regional differentiations. Paired comparisons showed significantly greater variability within- than between-groups, indi-cating significant differentiations between populations of different regional groups. Of all the pairwise comparisons, Hainan and Tibetan groups displayed the greatest differentiation, with the difference between the two groups being seven folds of that between populations within the groups; the least differentiations were exhibited between the groups of Hainan, Xinjiang, and Inner Mongolia, with the differences between groups being only half of the differences between populations within the groups. Mantel tests of the genetic and spatial distances showed that the two matrices were significantly correlated (p<0.01), indicating that the geographical isolation played an important role in the differentiations of the geographical populations of the migratory locusts. Cluster analysis divided all populations into four major groups: Xinjiang and Inner Mon-golia group, the Great Plains of North China (the Yellow River and Huai River Plains) group, Hainan group, and Tibet group. Principal component analysis (PCA) supported the division of populations based on the cluster analysis. However, analysis of individuals clustered the locusts into five populations: Xinjiang and Inner Mongolia, Hami in Xinjiang, the Great Plains of North China, Hainan, and Tibet. The locust populations in eastern China displayed apparently conti-nous and gradient variations; as such authors consider that there were no necessity and valid reasons for further division of subspecies. The subspecific status for the main geographical populations of the migratory locusts in China was discussed.
Helminth Community Dynamics in Populations of Blue-Winged Teal (Anas discors) Using Two Distinct Migratory Corridors  [PDF]
Jason M. Garvon,Alan M. Fedynich,Markus J. Peterson,Danny B. Pence
Journal of Parasitology Research , 2011, DOI: 10.1155/2011/306257
Abstract: The influence of spatially distinct host subpopulations on helminth community structure and pattern was examined in a migratory avian host species. Forty helminth species represented by 24,082 individuals were collected from 184 blue-winged teal (Anas discors; BWT) from 2 primary migratory corridors in Florida (eastern migratory corridor; EMC) and Louisiana and Texas (western migratory corridor; WMC). Mean species richness was greater in BWT from the WMC ( species) than the EMC (8.6 ± 0.2). The helminth community from the WMC had higher abundances of 6 common/intermediate species. Corridor helminth communities were similar in species composition but less similar when incorporating abundances of those species. Overlapping distributions of phylogenetically related host species that share generalist helminth species across ecologically similar habitats seem to mitigate the isolating mechanisms that are necessary for the distinct coevolutionary pathways to develop between adjacent corridors. 1. Introduction Helminth community dynamics among host populations are influenced by several factors such as variations in host feeding ecology [1], habitat use [2], distance between host populations [3–5], the phylogenetic relatedness of host species within an area coupled with host specificity of helminths [6, 7], and the resulting degree of host-parasite coevolution [8]. While many of the above relationships explain differences in helminth community structure (i.e., feeding ecology, habitat use, and distance between populations), others such as phylogenetic relatedness of hosts and host specificity of helminths (generalist rather than specialist) explain observed similarities among helminth communities. In addition to the factors mentioned above, helminth communities of waterfowl are subjected to the effects of migration that may accentuate the influence of other community-shaping factors. Several studies concerning helminth communities of waterfowl have addressed loss of helminths between migratory periods [9], effects of temporal variability on helminth communities within a single region [10], and differences in species richness between breeding and wintering grounds [11–13]. These authors tested ecological hypotheses using helminth communities from hosts within a single geographic region or migratory corridor. Wallace and Pence [9] proposed that if a migratory host species showed high fidelity to respective migratory corridors, after a substantial period of time, helminth communities unique to hosts within migratory corridors might be formed. Brooks’ [8]
Phenotypic Divergence among West European Populations of Reed Bunting Emberiza schoeniclus: The Effects of Migratory and Foraging Behaviours  [PDF]
Júlio M. Neto, Luís Gordinho, Eduardo J. Belda, Marcial Marín, Juan S. Monrós, Peter Fearon, Ross Crates
PLOS ONE , 2013, DOI: 10.1371/journal.pone.0063248
Abstract: Divergent selection and local adaptation are responsible for many phenotypic differences between populations, potentially leading to speciation through the evolution of reproductive barriers. Here we evaluated the morphometric divergence among west European populations of Reed Bunting in order to determine the extent of local adaptation relative to two important selection pressures often associated with speciation in birds: migration and diet. We show that, as expected by theory, migratory E. s. schoeniclus had longer and more pointed wings and a slightly smaller body mass than the resident subspecies, with the exception of E. s. lusitanica, which despite having rounder wings was the smallest of all subspecies. Tail length, however, did not vary according to the expectation (shorter tails in migrants) probably because it is strongly correlated with wing length and might take longer to evolve. E. s. witherbyi, which feed on insects hiding inside reed stems during the winter, had a very thick, stubby bill. In contrast, northern populations, which feed on seeds, had thinner bills. Despite being much smaller, the southern E. s. lusitanica had a significantly thicker, longer bill than migratory E. s. schoeniclus, whereas birds from the UK population had significantly shorter, thinner bills. Geometric morphometric analyses revealed that the southern subspecies have a more convex culmen than E. s. schoeniclus, and E. s. lusitanica differs from the nominate subspecies in bill shape to a greater extent than in linear bill measurements, especially in males. Birds with a more convex culmen are thought to exert a greater strength at the bill tip, which is in agreement with their feeding technique. Overall, the three subspecies occurring in Western Europe differ in a variety of traits following the patterns predicted from their migratory and foraging behaviours, strongly suggesting that these birds have became locally adapted through natural selection.
Constructing Phenetic and Phylogenetic Relationship Using Clad'97  [cached]
Brian Rahardi,Estri Laras Arumningtyas,Wayan Firdaus Mahmudi
Journal of Tropical Life Science , 2012,
Abstract: Relationship construction has a very important position in classification process for arranging taxonomy of organism. In the world of taxonomy, there are two the most familiar relationship diagram, cladogram and phenogram. In every construction activity, a researcher is always facing character state data from taxa that becomes components of the diagram. Calculation that is used for construction is often incorporate iterative or repetitive process that needs time and precision. The existence of calculating tools that produces both text and graphical output are hopefully decrease time and error during construction. Basic algorithm that is used in calculation is for phylogenetic construction by Kluge and Farris in 1969,for phenetic construction using cluster analysis with slight modification. Basic common algorithm used in the software is by calculating two dimensional arrays of taxa x characters matrix and creating distance or similarity matrix. In more detail the program creates one dimensional array of taxonomical object and each object has some other one dimensional array containing data commonly exist in a taxonomic unit. The relationship between one object and theother are regulated by an object that created by class representing taxonomic tree. Cladogram is constructed by calculating nearest distance between each taxon (OTU) and creating one HTU in every bifurcation. Phenogram is constructed agglomeratively by searching highest similarity between taxon then grouped into new taxon. Program calculates numerical data after we do character scoring. Final result for each user may be different; this may be due to decision by user during construction process. This paper hopefully attracts people from systematic computation to develop further into open source software and multi-platform feature.
Phenetic and geographic pattern of Aconitum sect. Napellus (Ranunculaceae) in the Eastern Carpathians - a numerical approach
Józef Mitka
Acta Societatis Botanicorum Poloniae , 2002, DOI: 10.5586/asbp.2002.005
Abstract: Aconitum sect. Napellus in the Eastern Carpathians was explored with the use of methods of numerical taxonomy*. The taxon consists of A. bucovinense Zapa . pro hybr., A.firmum Rchb. subsp. firmum, A. firmum subsp. fissurae Nyarady, A. fimum nsubsp.fussianum Starmuhl (A.firmum subsp. firmum x subsp. f'issurae), A. x nanum (Baumg.) Simonk. (A. bucovinense x A. firmum) and a hybrid A. firmum x A. x nanum. The taxi form phenetic continuum in a character hyperspace and their delimitation bases on a few traits, hitherto neglected, e.g. type of hairiness and flower morphology. A key is provided to identify taxa at all ranks within the supplemented of sect. Napellus. There is a regional pattern of particular OTUs distribution, which show local morphological uniqueness within a taxon. The phenomenon was inquired using the concept of "centers of phenetic coherence" (CPC) based on overall morphological similarity. The CPC may be interpreteted as regions of neoendemism and/or may reflect a post-glacial migratory route. High-mountain flora of the Western Bieszczady Mts. (sect. Napelus as its example) has features of neoendemism (schizoendemism), being most probably a result of geographical vicarism.
Enhanced Migratory Waterfowl Distribution Modeling by Inclusion of Depth to Water Table Data  [PDF]
Betty J. Kreakie, Ying Fan, Timothy H. Keitt
PLOS ONE , 2012, DOI: 10.1371/journal.pone.0030142
Abstract: In addition to being used as a tool for ecological understanding, management and conservation of migratory waterfowl rely heavily on distribution models; yet these models have poor accuracy when compared to models of other bird groups. The goal of this study is to offer methods to enhance our ability to accurately model the spatial distributions of six migratory waterfowl species. This goal is accomplished by creating models based on species-specific annual cycles and introducing a depth to water table (DWT) data set. The DWT data set, a wetland proxy, is a simulated long-term measure of the point either at or below the surface where climate and geological/topographic water fluxes balance. For species occurrences, the USGS' banding bird data for six relatively common species was used. Distribution models are constructed using Random Forest and MaxEnt. Random Forest classification of habitat and non-habitat provided a measure of DWT variable importance, which indicated that DWT is as important, and often more important, to model accuracy as temperature, precipitation, elevation, and an alternative wetland measure. MaxEnt models that included DWT in addition to traditional predictor variables had a considerable increase in classification accuracy. Also, MaxEnt models created with DWT often had higher accuracy when compared with models created with an alternative measure of wetland habitat. By comparing maps of predicted probability of occurrence and response curves, it is possible to explore how different species respond to water table depth and how a species responds in different seasons. The results of this analysis also illustrate that, as expected, all waterfowl species are tightly affiliated with shallow water table habitat. However, this study illustrates that the intensity of affiliation is not constant between seasons for a species, nor is it consistent between species.
Phenetic Analysis of Morphological and Molecular Traits in Acanthaceae Juss  [PDF]
Usama K. Abdel-Hameed, Mohamed E. Tantawy, Mohamed A. Salim, Magdy M. Mourad, Ishak F. Ishak
Journal of Biosciences and Medicines (JBM) , 2015, DOI: 10.4236/jbm.2015.33004
Abstract:

Acanthaceae has received considerable taxonomic attention at the familial, subfamilial, tribal and subtribal levels. Several different infra-familial classifications have been proposed for the Acanthaceae, but no taxonomic consensus has yet been reached. The main objective of the present study is to throw light on the phenetic relationships and to explore the contribution of morphological and molecular characters in systematics of Acanthaceae. The morphological data viz. macromorphology, stomatography, lamina architecture and ISSR profiles of 30 Egyptian acanthaceous taxa were investigated. The phenetic analysis using NTSYS-PC version 2.02 software based on 55 potentially informative morphological and molecular characters indicated that the used morphological and ISSR criteria is likely to be useful and valuable taxonomic traits. The morphological characters and ISSR aspects of all the studied species produced a phenogram that showed two series; one of them had two subseries, the first one comprised only three taxa while the second divided into two clusters, each contained two groups. The delimitation and the membership of the studied taxa clearly merit additional study using more criteria. The phenetic analysis of both morphological and molecular attributes clarified the segregation of genus Avicennia as a distinct identity away from Acanthaceae. Acanthus mollis & A. montanus are isolated in its own series that comparable to tribe Acantheae of the current taxonomic systems. The studied species of Thunbergia are gathered its own subseries that comparable to tribe Thunbergiae and Ruellia in its own group that comparable to tribe Ruellieae.

Modeling the Geography of Migratory Pathways and Stopover Habitats for Neotropical Migratory Birds  [cached]
Roger Tankersley, Jr.,Kenneth Orvis
Ecology and Society , 2003,
Abstract: Intact migratory routes are critical for the stability of forest-dwelling, neotropical, migratory bird populations, and mortality along migratory pathways may be significant. Yet we know almost nothing about the geography of available stopovers or the possible migratory pathways that connect optimal stopovers. We undertake a spatial analysis of stopover habitat availability and then model potential migratory pathways between optimal stopovers in the eastern United States. Using models of fixed orientation and fixed nightly flight distance between stopovers during spring migration, we explore whether a simple endogenous migratory program is sufficient to ensure successful migration across the modern landscape. Our model runs suggest that the modern distribution of optimum stopovers in the eastern United States can be adequately exploited by birds following migratory pathways defined by fixed-orientation and fixed-distance nightly flights. Longer flight distances may increase the chances of success by enabling migrants to bypass locales offering little habitat. Our results also suggest that most southwest–northeast migratory pathways through the Appalachian mountains are intact. Lack of optimal habitat at key locations in the Southeast causes many modeled pathways to fail. We present a speculative view of regional migration patterns implied by predominant ideas found in stopover ecology literature, and demonstrate the need for broad-scale migration research, in the hope that our approach will foster other continental- and regional-scale projects.
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