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Population structure and sexual maturity of the calico box crab Hepatus epheliticus Linnaeus (Brachyura, Hepatidae) from Yucatan Peninsula, Mexico

Hernáez, Patricio; Rombenso, Artur; Pinheiro, Marcelo A. A.; Simoes, Nuno
Fonte: UNIV CATOLICA DE VALPARAISO; VALPARAISO Publicador: UNIV CATOLICA DE VALPARAISO; VALPARAISO
Tipo: Artigo de Revista Científica
ENG
Relevância na Pesquisa
65.83%
The calico box crab Hepatus epheliticus is an abundant species from shallow and continental shelf waters of the Atlantic coast of USA and Mexico. Information about population structure and sexual maturity is absent, even though this crab is caught to be used as bait for the octopus fishery in the Campeche Bank, Mexico. In order to achieve such information, a total of 768 individuals were collected from January to March 2010 through baited traps installed in the Yucatan Peninsula, Mexico. Our results showed that sex ratio is biased towards more males than females (1:0.55), contradicting to that reported in other brachyuran crabs. The absence of ovigerous females suggests that they did not enter into the traps during embryogenesis. Males reached a larger maximum size than females (64.0 +/- 6.15 and 58.4 +/- 5.60 mm carapace width, respectively). The general scheme of growth being positive allometric throughout ontogeny of both sexes. Males presented a transition phase from juveniles to adult corresponding to the puberty moult. The estimation of the onset of functional sexual maturity revealed a steady situation for the population, with 21.5 and 13.8% of males and females, respectively, morphologically immature at the time of catch. This study constitutes the first report on population structure and sexual maturity in a population of the calico box crab H. epheliticus.; Red de Macrouniversidades de America Latina y El Caribe (Red MACRO)

Initial description of the phylogeography, population structure and genetic diversity of Atlantic spotted dolphins from Brazil and the Caribbean, inferred from analyses of mitochondrial and nuclear DNA

Caballero, Susana; Santos, Marcos César de Oliveira; Sanches, Alexandra; Mignucci-Giannoni, Antonio A.
Fonte: Biblioteca Digital da Produção Intelectual da USP Publicador: Biblioteca Digital da Produção Intelectual da USP
Tipo: Artigo de Revista Científica
ENG
Relevância na Pesquisa
65.85%
We provide initial information regarding the population structure and genetic diversity of Stenella frontalis from the Caribbean and southeastern Brazil from analyses of mitochondrial control region sequences and sequences from the first intron of the α-lactalbumin gene. Comparisons with previously described S. frontalis sequences showed a high number of haplotypes shared between populations throughout their distribution range. High diversity was found for southeastern Brazil and Caribbean samples, and population structure analyses indicate significant differentiation among population units at the FST level, but not at the ΦST level. Significant differentiation at the FST level was found between the Caribbean population unit and all other populations units. These results suggest historical or present connectivity between the Azores and Madeira and the southeastern Brazil groups and population differentiation between the Caribbean and southeastern Brazil, supporting the notion of two separate stocks in the waters around the Atlantic coast of South America.; Instituto Earthwatch; W. Rossiter and Cetacean Society International; CNPq - 308331/2010-9; FAPESP - 05/59439-5; CNPq - 05/54149-9; Instituto Chico Mendes de Conservação da Biodiversidade - 15572-2

Estudo da estrutura populacional em cana-de-açúcar usando marcadores do tipo SNP; Evaluation of population structure in sugarcane using SNP markers

Silva, Renato Rodrigues
Fonte: Biblioteca Digitais de Teses e Dissertações da USP Publicador: Biblioteca Digitais de Teses e Dissertações da USP
Tipo: Tese de Doutorado Formato: application/pdf
Publicado em 22/03/2013 PT
Relevância na Pesquisa
65.9%
Embora já existam estudos anteriores a respeito da estrutura de população em cana-deaçúcar, até o momento nenhum estudo foi feito usando marcadores SNPs gerados a partir de plataformas de genotipagem de larga escala, como por exemplo, Sequenom iPLEX MassARRAY. No presente trabalho, foi investigada a estrutura populacional no painel brasileiro de variedades de cana-de-açúcar. Esse painel é formado por materiais elites, ancestrais importantes e cultivares utilizados em programa de melhoramento. Um total de 1033 marcadores SNPs foram utilizados para genotipar os acessos do painel. A classificação dos dados feita usando o software SuperMASSA. A estrutura de população foi analisada por meio de análise de componentes principais (ACP), análise de agrupamentos e usando o software STRUCTURE. Devido ao fato que no software STRUCTURE não é possível dados de marcadores moleculares provenientes de espécies poliploides com aneuplodia frequente, o conjunto de dados foi separado e analisado de acordo com nível de ploidias dos SNPs. Com a finalidade de comparar os resultados, foi feita uma análise de coordenadas principais na matriz de distância, com os elementos definidos por 1 - coeficiente de parentesco. A análise de componentes principais revelou presença de estrutura de população. O primeiro componente separou o acesso IN84-58 (S. spontaneum) dos outros acessos que por sua vez estão separados em três grupos: o primeiro grupo formado pelos acessos que são S. sinense...

Population structure and sexual maturity of the calico box crab Hepatus epheliticus Linnaeus (Brachyura, Hepatidae) from Yucatan Peninsula, Mexico

Hernaez, Patricio; Rombenso, Artur; Pinheiro, Marcelo A. A.; Simoes, Nuno
Fonte: Universidade Católica de Valparaíso Publicador: Universidade Católica de Valparaíso
Tipo: Artigo de Revista Científica Formato: 480-486
ENG
Relevância na Pesquisa
65.83%
The calico box crab Hepatus epheliticus is an abundant species from shallow and continental shelf waters of the Atlantic coast of USA and Mexico. Information about population structure and sexual maturity is absent, even though this crab is caught to be used as bait for the octopus fishery in the Campeche Bank, Mexico. In order to achieve such information, a total of 768 individuals were collected from January to March 2010 through baited traps installed in the Yucatan Peninsula, Mexico. Our results showed that sex ratio is biased towards more males than females (1:0.55), contradicting to that reported in other brachyuran crabs. The absence of ovigerous females suggests that they did not enter into the traps during embryogenesis. Males reached a larger maximum size than females (64.0 +/- 6.15 and 58.4 +/- 5.60 mm carapace width, respectively). The general scheme of growth being positive allometric throughout ontogeny of both sexes. Males presented a transition phase from juveniles to adult corresponding to the puberty moult. The estimation of the onset of functional sexual maturity revealed a steady situation for the population, with 21.5 and 13.8% of males and females, respectively, morphologically immature at the time of catch. This study constitutes the first report on population structure and sexual maturity in a population of the calico box crab H. epheliticus.

Phylogeography and genetic population structure of Caribbean sharpnose shark Rhizoprionodon porosus

Mendonca, Fernando F.; Oliveira, Claudio; Gadig, Otto Bismarck Fazzano; Foresti, Fausto
Fonte: Springer Publicador: Springer
Tipo: Artigo de Revista Científica Formato: 799-814
ENG
Relevância na Pesquisa
65.84%
Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP); Processo FAPESP: 06/588972; Sharks of the genus Rhizoprionodon are among the most important predators along the coastal marine ecosystems, and they represent an important economic resource for the small-scale fisheries. To properly manage and conserve exploited shark species, detailed analyses of their population structure are needed. To evaluate the gene flow and levels of the genetic diversity among populations of the Caribbean sharpnose shark R. porosus, we identified the nucleotide sequence based on collections (n = 321 specimens) from 10 different areas, including the Caribbean Sea and several locations along the entire Brazilian coast. The analysis of 802 nucleotides from the mitochondrial DNA control region revealed 53 distinct haplotypes. The majority of these haplotypes were restricted to their collection locales with a significant genetic structure detected among the overall populations (Phi(ST) = 0.237, P < 0.0001). The data suggest a population division with two distinct management units in the western Atlantic. These management units are likely separated by the Equatorial Current. The strong population structure in R. porosus indicates that regional populations...

Comparison of the population structure of the fiddler crab Uca vocator (Herbst, 1804) from three subtropical mangrove forests

Colpo, Karine Delevati; Negreiros-Fransozo, Maria Lucia
Fonte: Universidade Estadual Paulista Publicador: Universidade Estadual Paulista
Tipo: Artigo de Revista Científica Formato: 139-146
ENG
Relevância na Pesquisa
65.82%
The population structure of U. vocator was investigated during a one-year period in three mangrove forests in southeast Brazil. The study specifically addressed comparisons on individual size juvenile recruitment and sex-ratio. The structure of the mangrove forests, i.e. density, basal area, and diameter, and the physical properties of sediments. i.e. texture and organic matter contents, were also examined. A catch-per-unit-effort (CPUE) technique was used to sample the crab populations using 15-min sampling periods by two people. Males always outnumbered females, probably due to ecological and behavioural attributes of these crabs. The median size of fiddler crabs differed among the sampled populations. The mangroves at Indaiá and Itamambuca showed higher productivity than those at Itapanhaú, where oil spills impacting the shore were reported. Marked differences were found regarding individual size, either their size at the onset of sexual maturity or their asymptotic size, suggesting that food availability may be favouring growth in the studied populations.

Population structure of the seabob shrimp Xiphopenaeus kroyeri (Heller, 1862) (Crustacea: Penaeoidea) in the littoral of São Paulo, Brazil

Castro, Rodrigo H.; Costa, Rogério C.; Fransozo, Adilson; Mantelatto, Fernando L. M.
Fonte: Universidade Estadual Paulista Publicador: Universidade Estadual Paulista
Tipo: Artigo de Revista Científica Formato: 105-112
ENG
Relevância na Pesquisa
65.84%
The population structure of the penaeidean shrimp Xyphopenacus kroyeri was studied in Ubatuba Bay, Ubatuba, Sd̃ao Paulo, Brazil. The period and site of juvenile recruitment were monitored using a monthly sampling design with eight fixed areas (transects) from September 1995 to August 1996. The population structure was assessed using size frequency distributions (based on carapace length) for each month and sampling area. Females were significantly larger than males, suggesting a differential growth between sexes. The very low occurrence of large adults in the Bay can be related to offshore migration for reproduction. Recruitment occurred throughout the year, with a peak during the summer, when the highest recruitment rates were obtained along inshore transects. The present investigation revealed valuable information on the biology of the species mainly in the study region, which is considered a nursery ground for juveniles of X. kroyeri. The species showed an important variation from the typical life cycle that it is assumed to hold over its entire range and X. kroyeri should be classified as having a life cycle different from that proposed previously in the literature, i.e. the juveniles prefer inshore areas instead of estuaries. Some suggestions for the seabob fishery management are proposed as an alternative for minimising the impact during the harvest period and adjusting the protection schedule.

Initial description of the phylogeography, population structure and genetic diversity of Atlantic spotted dolphins from Brazil and the Caribbean, inferred from analyses of mitochondrial and nuclear DNA

Caballero, Susana; de O. Santos, Marcos C.; Sanches, Alexandra; Mignucci-Giannoni, Antonio A.
Fonte: Universidade Estadual Paulista Publicador: Universidade Estadual Paulista
Tipo: Artigo de Revista Científica Formato: 263-270
ENG
Relevância na Pesquisa
65.88%
We provide initial information regarding the population structure and genetic diversity of Stenella frontalis from the Caribbean and southeastern Brazil from analyses of mitochondrial control region sequences and sequences from the first intron of the α-lactalbumin gene. Comparisons with previously described S. frontalis sequences showed a high number of haplotypes shared between populations throughout their distribution range. High diversity was found for southeastern Brazil and Caribbean samples, and population structure analyses indicate significant differentiation among population units at the FST level, but not at the ΦST level. Significant differentiation at the FST level was found between the Caribbean population unit and all other populations units. These results suggest historical or present connectivity between the Azores and Madeira and the southeastern Brazil groups and population differentiation between the Caribbean and southeastern Brazil, supporting the notion of two separate stocks in the waters around the Atlantic coast of South America. © 2013 Elsevier Ltd.

Genetic diversity and population structure of the Guinea pig (Cavia porcellus, Rodentia, caviidae) in Colombia

Burgos-Paz,William; Cerón-Muñoz,Mario; Solarte-Portilla,Carlos
Fonte: Sociedade Brasileira de Genética Publicador: Sociedade Brasileira de Genética
Tipo: Artigo de Revista Científica Formato: text/html
Publicado em 01/01/2011 EN
Relevância na Pesquisa
65.77%
The aim was to establish the genetic diversity and population structure of three guinea pig lines, from seven production zones located in Nariño, southwest Colombia. A total of 384 individuals were genotyped with six microsatellite markers. The measurement of intrapopulation diversity revealed allelic richness ranging from 3.0 to 6.56, and observed heterozygosity (Ho) from 0.33 to 0.60, with a deficit in heterozygous individuals. Although statistically significant (p < 0.05), genetic differentiation between population pairs was found to be low. Genetic distance, as well as clustering of guinea-pig lines and populations, coincided with the historical and geographical distribution of the populations. Likewise, high genetic identity between improved and native lines was established. An analysis of group probabilistic assignment revealed that each line should not be considered as a genetically homogeneous group. The findings corroborate the absorption of native genetic material into the improved line introduced into Colombia from Peru. It is necessary to establish conservation programs for native-line individuals in Nariño, and control genealogical and production records in order to reduce the inbreeding values in the populations.

Plant population structure and insect herbivory on Solanum mauritianum Scopoli (Solanaceae) in southern Brazil: a support to biological control

Barboza,Deise Mari; Marques,Márcia Cristina Mendes; Pedrosa-Macedo,José Henrique; Olckers,Terence
Fonte: Instituto de Tecnologia do Paraná - Tecpar Publicador: Instituto de Tecnologia do Paraná - Tecpar
Tipo: Artigo de Revista Científica Formato: text/html
Publicado em 01/04/2009 EN
Relevância na Pesquisa
65.82%
Solanum mauritianum Scopoli (Solanaceae), a native Brazilian shrub, has become naturalized and invasive in several countries. In South Africa, where invasions are severe, herbivorous insects that attack S. mauritianum in its native area have been considered for introduction as biological control agents. To assess the action of such herbivores on the plant, studies were carried out on a population of S. mauritianum in an area undergoing regeneration in southern Brazil. An analysis of the structure of that population was performed, as well as of herbivory by insects, in particular of Anthonomus (Curculionidae). The population structure showed an "inverted J" pattern in diameter classes, but not in height classes. Individual plants showed an aggregate distribution. The damage caused by Anthonomus did not amount to the loss of a large leaf area, but since it was inflicted on young leaves and in a large proportion, could lead to the survival decrease.

Characterizing the genetic population structure of the razorbill (Alca torda) using next-generation sequencing

Shakory, Shima
Fonte: Quens University Publicador: Quens University
Tipo: Tese de Doutorado
EN
Relevância na Pesquisa
65.87%
Seabirds are useful tools in conservation management because of their status as environmental indicator species. As such, concern exists about the preservation of seabird species such as the razorbill (Alca torda). The razorbill is a colonial seabird distributed along the arctic and boreal regions of the North Atlantic. Given that razorbills have a relatively small population in North America, have previously suffered significant population losses and are vulnerable to many sources of mortality, management action is required for the conservation of the species. Because conservation requires the separate treatment of genetically differentiated populations, I characterized the species’ genetic population structure using next-generation sequencing. Double-digest Restriction-site Associated DNA sequencing (ddRADseq) provides a new and potentially powerful way to determine the genetic relationships among local colonies of the razorbill at higher resolution than was possible with traditional genetic analyses. I compared 410 loci among 44 razorbills from eight sampling sites throughout their range. In a separate analysis of only North American samples, I compared 2,663 loci among 36 razorbills from five sampling sites in Eastern Canada. I found no significant population structure...

Using stylet elemental signatures to determine the population structure of Octopus maorum

Doubleday, Z.; Pecl, G.; Semmens, J.; Danyushevsky, L.
Fonte: Inter-Research Publicador: Inter-Research
Tipo: Artigo de Revista Científica
Publicado em //2008 EN
Relevância na Pesquisa
65.83%
A novel method was used to investigate the population structure and dispersal patterns of Octopus maorum, an octopus species with a planktonic larval stage, which forms a distinct and large aggregation in southeast Tasmania. Single and multi-elemental signatures within the ‘early life history’ region of the stylet (an internal ‘shell’) were used to determine levels of connectivity and the common origins of individuals collected from 5 locations across Tasmania, South Australia and New Zealand. Using laser ablation inductively coupled plasma-mass spectrometry (LA ICPMS) the stylets were analysed for 12 elements, 8 of which were found to be excellent spatial discriminators. There was evidence of population structuring within the O. maorum population, with a distinct separation of the aggregation site in southeast Tasmania from other groups. Octopuses from the aggregation shared a common origin and appeared to be coming from a local neighbouring source. The 2 northern sample locations shared a similar elemental signature, which could be due to either similar water chemistries or long-distance dispersal. This study presents the first insights into the population structure of O. maorum, and provides vital information for the sustainable management of this species. Furthermore...

Alternate foraging strategies and population structure of adult female Australian sea lions.

Lowther, Andrew Damon
Fonte: Universidade de Adelaide Publicador: Universidade de Adelaide
Tipo: Tese de Doutorado
Publicado em //2012
Relevância na Pesquisa
65.91%
Otariid seals pose several challenges in collecting behavioural data due because of the geographical decoupling of breeding habitat (terrestrial) and foraging grounds (aquatic). Additionally, life history traits such as breeding chronology and moult state constrain the temporal window over which data can be collected. Expensive telemetry devices coupled with logistical difficulties and the biology of animals often limits the ability to answer questions concerning the role of seasonal or life-history differences in foraging ecology. However, quantifying individual behavioural specialisations such as foraging behaviour that may impede gene flow is an essential prerequisite to understanding population structure. Several unusual life history traits of the IUCN Red Listed (threatened) Australian sea lion Neophoca cinerea are interesting from an ecological, evolutionary and conservation standpoint. Australian sea lions are endemic to the southern and western coastline of Australia, distributed over approximately 70 breeding colonies with 86% of all breeding occurring in South Australia. Most notably, a unique 17.5month breeding chronology and asynchronous breeding between spatially-close colonies has been proposed to be an adaptive response to a low-quality foraging environment that has little or no seasonality. Contrary to this...

Stylet elemental signatures indicate population structure in a holobenthic octopus species, Octopus pallidus

Doubleday, Z.; Pecl, G.; Semmens, J.; Danyushevsky, L.
Fonte: Inter-Research Publicador: Inter-Research
Tipo: Artigo de Revista Científica
Publicado em //2008 EN
Relevância na Pesquisa
65.82%
Targeted trace elemental analysis was used to investigate the population structure and dispersal patterns of the holobenthic octopus species Octopus pallidus (Hoyle, 1885). Multi-elemental signatures within the pre-hatch region of the stylet (an internal 'shell') were used to determine the common origins and levels of connectivity of individuals collected from 5 locations in Tasmania. To determine whether hatchling elemental signatures could be used as tags for natal origin, hatchling stylets from 3 of the 5 locations were also analysed. We analyzed 12 elements using laser ablation inductively-coupled plasma-mass spectrometry (LAICPMS). Of the 12 elements, 7 were excellent spatial discriminators. There was evidence of high-level structuring with distinct groupings between all sites (the 2 closest being 85 km apart) within the adult O. pallidus population, suggesting that all adults had hatched in or near their respective collection sites. The hatchling signatures showed significant spatial variation, and a high percentage of individuals could successfully be traced back to their collection locations. However, they could not be used to trace adults back to their natal site, due to significant differences in element concentrations in hatchling and adult stylets...

Population structure of the rice sheath blight pathogen Rhizoctonia solani AG-1 IA from India

Linde, Celeste; Zala, Marcello; Paulraj, R S; McDonald, Bruce A; Gnanamanickam, Sam
Fonte: Springer Publicador: Springer
Tipo: Artigo de Revista Científica
Relevância na Pesquisa
65.85%
The population structure of Rhizoctonia solani AG-1 IA causing rice sheath blight from India was evaluated for 96 isolates using seven RFLP loci. Nineteen of the isolates did not hybridise to R. solani AG-1 IA RFLP probes and rDNA analyses subsequently confirmed that they were either Ceratobasidium oryzae-sativae isolates or another Rhizoctonia sp. The population structure of the remaining 77 R. solani AG-1 IA Indian isolates was similar to that of a previously characterized Texas population. Clonal dispersal of R. solani AG-1 IA in India was moderate within fields and no clones were shared among field populations. Low levels of population subdivision and small genetic distances among populations were consistent with high levels of gene flow. Frequent sexual reproduction was indicated by the fact that most populations were in Hardy-Weinberg equilibrium (HWE). The two loci (R68 and R111) that deviated significantly from HWE showed an excess of heterozygosity. Although Texas and Indian populations were geographically very distant, they exhibited only moderate population subdivision, with an F ST value of 0.193.

Population structure, sex ratio and abundance of Podocnemis sextuberculata (Testudines, Podocnemididae) in the Reserva de Desenvolvimento Sustentável Mamirauá, Amazonas, Brazil; Estrutura populacional, razão sexual e abundância de Podocnemis sextuberculata (Testudines, Podocnemididae) na Reserva de Desenvolvimento Sustentável Mamirauá, Amazonas, Brasil

Fachín-Terán, Augusto; Vogt, Richard C.; Thorbjarnarson, John B.
Fonte: Universidade de São Paulo. Escola Superior de Agricultura Luiz de Queiróz Publicador: Universidade de São Paulo. Escola Superior de Agricultura Luiz de Queiróz
Tipo: info:eu-repo/semantics/article; info:eu-repo/semantics/publishedVersion; ; Formato: application/pdf
Publicado em 01/06/2003 POR
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65.84%
Population structure, sex ratio and abundance of Podocnemis sextuberculata (Testudines, Podocnemididae) in the Reserva de Desenvolvimento Sustentável Mamirauá, Amazonas, Brazil. We studied turtles in the focal area of the Reserva de Desenvolvimento Sustentável Mamirauá from September 1996 through August 1998. The reserve is located in the western part of the Brazilian Amazon, between the Japurá, Solimões, and Auti-Paraná rivers, near the city of Tefé, in the state of Amazonas. In this study the populacion structure, sex ratio and abundance of Podocnemis sextuberculata were investigated. We intensively studied the population of turtles in the Jarauá river basin in order to determine population structure. We sampled turtles in different sectors of the focal area of the reserve for one month each year during July and August 1997 and 1998. We captured the turtles using flag gill nets and trammel nets. The type of net and size of the nets used influenced the size of the turtles captured. The nets used by the local fishermen were sexually selective in the capture of turtles. Seventy two per cent of the P. sextuberculata captured were adults; 13 % juveniles and 14.7 % subadults. During the second year of the study we found a lower density of turtles in the five areas which we sampled both years. The sex ratio of captured P. sextuberculata was 1.87 males per female.

Impact of forest fragment size on the population structure of three palm species (Arecaceae) in the Brazilian Atlantic Rainforest

Quitete Portela,Rita de Cássia; Maes dos Santos,Flavio Antonio
Fonte: Revista de Biología Tropical Publicador: Revista de Biología Tropical
Tipo: Artigo de Revista Científica Formato: text/html
Publicado em 01/06/2014 EN
Relevância na Pesquisa
65.87%
The main threats to natural populations in terrestrial ecosystems have been widly recognized to be the habitat fragmentation and the exploitation of forest products. In this study, we compared the density of the populations and the structure of three tropical palm species, Astrocaryum aculeatissimum, Euterpe edulis and Geonoma schottiana. For this, we selected five forest fragments of different sizes (3 500ha, 2 400ha, 57ha, 21ha and 19ha) where palms were censused in nine 30x30m plots. We tracked the palms survival from 2005 to 2007, and recorded all new individuals encountered. Each individual was assigned in one of the five ontogenetic stages: seedling, infant, juvenile, immature and reproductive. The demographic structure of each palm species was analyzed and compared by a generalized linear model (GLM). The analysis was performed per palm spe-cies. The forest fragment area and the year of observation were explanatory variables, and the proportion of individuals in each ontogenetic class and palm density were response variables. The total number of individuals (from seedlings to reproductives, of all species) monitored was 6 450 in 2005, 7 268 in 2006, and 8 664 in 2007. The densities of two palm species were not influenced by the size of the fragment...

Microsatellites loci reveal heterozygosis and population structure in vampire bats (Desmodus rotundus) (Chiroptera: Phyllostomidae) of Mexico

Romero-Nava,Claudia; León-Paniagua,Livia; Ortega,Jorge
Fonte: Revista de Biología Tropical Publicador: Revista de Biología Tropical
Tipo: Artigo de Revista Científica Formato: text/html
Publicado em 01/06/2014 EN
Relevância na Pesquisa
65.84%
A limited number of studies have focused on the population genetic structure of vampire bats (Desmodus rotundus) in America. This medium-sized bat is distributed in tropical areas of the continent with high prevalence in forested livestock areas. The aim of this work was to characterize the vampire population structure and their genetic differentiation. For this, we followed standard methods by which live vampires (caught by mist-netting) and preserved material from scientific collections, were obtained for a total of 15 different locations, ranging from Chihuahua (North) to Quintana Roo (Southeast). Tissue samples were obtained from both live and collected animals, and the genetic differentiation, within and among localities, was assessed by the use of seven microsatellite loci. Our results showed that all loci were polymorphic and no private alleles were detected. High levels of heterozygosis were detected when the proportion of alleles in each locus were compared. Pairwise F ST and R ST detected significant genetic differentiation among individuals from different localities. Our population structure results indicate the presence of eleven clusters, with a high percentage of assigned individuals to some specific collecting site. Rev. Biol. Trop. 62 (2): 659-669. Epub 2014 June 01.

Genetic diversity and population structure of locally adapted South African chicken lines: implications for conservation

van Marle-Köster,E.; Hefer,C.A.; Nel,L.H.; Groenen,M.A.M.
Fonte: South African Journal of Animal Science Publicador: South African Journal of Animal Science
Tipo: Artigo de Revista Científica Formato: text/html
Publicado em 01/04/2008 EN
Relevância na Pesquisa
65.82%
In this study microsatellite markers were applied to investigate the genetic diversity and population structure of the six local chicken lines kept in the "Fowls for Africa" program, for better clarification of parameters for breed differentiation and genetic conservation of this valuable resource. The lines included the Black Australorp, Potchefstroom Koekoek, New Hampshire, Ovambo, Lebova- Venda and a Naked Neck line. Unbiased estimates for heterozygosity ranged from 50% in the Potchefstroom Koekoek to as high as 65% in the Naked Neck chickens. F IS values varied from as low as 0.16 for the Black Australorp line to as high as 0.35 for the Ovambo chickens. The FST values indicated moderate to high genetic differentiation between the Naked Neck and New Hampshire (0.11); Ovambo and Naked Neck lines (0.12), and Naked Neck and Lebowa- Venda (0.14). A total of 13% of the total genetic variation observed was between the chicken lines and 87% within the lines, supporting moderate genetic differentiation. Population structure was assessed using STRUCTURE where the Black Australorp was genetically best defined. Although six clusters for the different populations could be distinguished, the other lines were not as clearly defined, with individual birds tending to share more than one cluster. Results support a broad classification of these lines and further investigation of unique alleles is recommended for conservation of the lines within the program.

Density and population structure of the red land crab gecarcinus lateralis in a tropical semi-deciduous forest in veracruz, mexico

Capistrán-Barradas,Ascención; Defeo,Omar; Moreno-Casasola,Patricia
Fonte: ASOCIACIÓN INTERCIENCIA Publicador: ASOCIACIÓN INTERCIENCIA
Tipo: Artigo de Revista Científica Formato: text/html
Publicado em 01/06/2003 EN
Relevância na Pesquisa
65.84%
The variation in density and population structure of the land crab Gecarcinus lateralis (Gecarcinidae) was studied in a tropical semi-deciduous forest on the coast of Veracruz, Mexico. Crab density changed as a function of forest type (old or young), forest cover (understorey or gap), and year (1997 and 1998). In 1997, crab density was similar between old forest (OF) and young forest (YF), gaps and understorey, and between floor topographies. However, in 1998, crab density was higher in OF as compared to YF, and understorey in relation to gaps. For both years, crab density in the understorey of valleys and peaks was higher than in gaps. The population age structure of G. lateralis (as determined by burrow size) also varied as a function of forest age, floor topography, and forest cover. For both years, bigger crabs were found in YF than in OF, in valleys and slopes relative to peaks, and in the understorey as opposed to gaps. Forest variations in soil characteristics (humidity, amount of leaf litter and compaction) are invoked as explanatory variables for the observed differences in density and population structure of G. lateralis