Search

Myotis septentrionalis (Northern Long-eared Bat) has recently suffered a >90% decline in population size in North America due to white-nose syndrome (WNS). We assessed genetic diversity, population structure, current effective population size, and demographic history of M. septentrionalis distributed across the United States to determine baseline levels pre-WNS. We analyzed RADseq data from 81 individuals from Kentucky, Louisiana, Michigan, Minnesota, North Carolina, Oklahoma, and Wisconsin. Additionally, we examined population genetic structure using discriminant analysis of principal components, fastStructure, and STRUCTURE. We then estimated effective population size and demographic history using fastsimcoal2. Similar levels of genetic diversity were found across all samples. We found no population genetic structure in the varied analyses from these contemporary samples. The best model for demographic history estimated a rapid population expansion followed by a slower expansion approximately 340,000 years ago. The vagility of M. septentrionalis , along with male dispersal and random mating, may provide a buffer against serious bottleneck effects stemming from rapid population declines due to WNS. This research provides a baseline for tracking and monitoring the influence of WNS on genetic diversity such as potential reduced diversity or increased population structuring in the future. [ABSTRACT FROM AUTHOR]

Owing to extensive overexploitation and continuous habitat loss in recent decades, Dalbergia stevensonii has become endangered in Central America and its place of origin. Genetic diversity is essential for ensuring the long-term survival of the species and is vital in breeding programs. However, knowledge of the genetic diversity ofD. stevensonii is limited, as no study has been conducted to estimate the population variability in Guatemala. This study is the first to determine the genetic diversity and structure of wild populations of D. stevensonii in Guatemala using molecular markers. The genetic diversity of 90 wild D. stevensonii trees from six populations located in their natural range is currently being evaluated. Genetic diversity was moderate, with an average of 5.83 alleles per locus, a mean Shannon index value of 1.42, and observed and expected heterozygosity of 0.32 and 0.37, respectively. AMOVA indicated that only 6 % of the genetic variation was between populations, and genetic distance values (pairwise FST) suggested moderate differentiation between populations. STRUCTURE and DAPC analyses revealed the existence of three clusters for the 90 samples, while the genetic differentiation among populations is attributed more to genetics than to geographic distance. Conservation of the genetic diversity of D. stevensonii is critical to ensure its long-term survival, and the success of breeding programs focused on improving the traits and characteristics of the species, such as growth rate, wood quality, and resistance to pests and diseases. These findings provide a crucial genetic basis for conservation, management, and restoration of this endemic species. [ABSTRACT FROM AUTHOR]

The savannah side-necked turtle Podocnemis vogli is a species restricted to the savannas of the Orinoco basin in Colombia and Venezuela. Because of its apparent abundance, it is currently categorized as Least Concern (LC) by the IUCN Red List. However, throughout its distribution range, several populations have been extirpated or individuals in remaining populations are consumed and trafficked, and the species' habitat has been highly degraded. To start assessing the conservation status of the species, 5 populations along their distribution range in Colombia were analyzed using 19 microsatellite loci to perform a population genetics study. Ten of those markers were useful in revealing (1) high levels of genetic diversity, (2) a marked genetic structure of 5 populations, and (3) low and asymmetric gene flow among them. However, the analyses also revealed the loss of genetic diversity (low allelic richness) and recent bottlenecks in some populations. Those identified detrimental indicators are evidencing a population decline most likely related to anthropic activities. These 5 populations correspond to 5 independent management units. The results of this research allow us to propose management and conservation guidelines for these populations in the Orinoco ecoregion. Resumen La tortuga sabanera Podocnemis vogli es una especie restringida a las sabanas de la cuenca del Orinoco en Colombia y Venezuela. Debido a su aparente abundancia, actualmente está categorizada como en Preocupación Menor (LC) por la Lista Roja de la UICN. Sin embargo, a lo largo de su rango de distribución, varias poblaciones han sido extirpadas o los individuos en poblaciones remanentes son consumidos y traficados, y el hábitat de la especie se ha degradado intensamente. Para comenzar a evaluar el estado de conservación de la especie, se analizaron cinco poblaciones a lo largo de su rango de distribución en Colombia utilizando 19 loci microsatélites para realizar un estudio de genética poblacional. Diez de esos marcadores fueron útiles para revelar: (1) altos niveles de diversidad genética, (2) una estructura genética marcada de cinco poblaciones y (3) flujo de genes bajo y asimétrico entre ellas. Sin embargo, los análisis también revelaron la pérdida de diversidad genética (baja riqueza alélica) y cuellos de botella recientes en algunas poblaciones. Esos indicadores perjudiciales identificados están evidenciando una disminución de las poblaciones, muy probablemente relacionada con las actividades antrópicas. Estas cinco poblaciones corresponden a cinco Unidades de Manejo Independientes. Los resultados de esta investigación nos permiten proponer lineamientos de manejo y conservación para estas poblaciones en la ecorregión del Orinoco. [ABSTRACT FROM AUTHOR]

In high-latitude species with high dispersal ability, such as long-distance migratory birds, populations are often assumed to exhibit little genetic structure due to high gene flow or recent postglacial expansion. We sequenced over 120 low-coverage whole genomes from across the breeding range of a long-distance migratory bird, the Veery (Catharus fuscescens), revealing strong evidence for isolation by distance. Additionally, we found distinct genetic structure between boreal, western montane U.S. and southern Appalachian sampling regions. We suggest that population genetic structure in this highly migratory species is detectable with the high resolution afforded by whole-genomic data because, similar to many migratory birds, the Veery exhibits high breeding-site fidelity, which likely limits gene flow. Resolution of isolation by distance across the breeding range was sufficient to assign likely breeding origins of individuals sampled in this species' poorly understood South American nonbreeding range, demonstrating the potential to assess migratory connectivity in this species using genomic data. As the Veery's breeding range extends across both historically glaciated and unglaciated regions in North America, we also evaluated whether contemporary patterns of structure and genetic diversity are consistent with historical population isolation in glacial refugia. We found that patterns of genetic diversity did not support southern montane regions (southern Appalachians or western U.S. mountains) as glacial refugia. Overall, our findings suggest that isolation by distance yields subtle associations between genetic structure and geography across the breeding range of this highly vagile species even in the absence of obvious historical vicariance or contemporary barriers to dispersal. [ABSTRACT FROM AUTHOR]

Copyright of Biological Invasions is the property of Springer Nature and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Wetlands is the property of Springer Nature and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Contextualization: The analysis of genetic diversity is essential to preserve and adequately harness genetic resources, both plant and animal, and it is transcendental for developing selection and improvement strategies to obtain promising materials. Knowledge gap: There are few studies of characterization and analysis reported of genetic variability for mulberry Morus spp. in Colombia and need to be developed in order to provide information that enables refining and optimizing the management, use, and conservation of the available germplasm, contributing to the recovery and harnessing of these genetic resources' potential. Purpose: The research aimed to genetically characterize the mulberry, Morus spp., collection of the Cauca region sericulture project using microsatellite markers. Methodology: 36 accessions belonging to the mulberry collection conserved at the Centro de Estudios Vegetales La Rejoya (Center for Plant Studies La Rejoya in English) of Universidad del Cauca were evaluated using ten microsatellites fluorescently labeled. The diversity and genetic structure parameters were evaluated. Additionally, the genetic relationships were determined through a cluster analysis. Results and conclusions: 49 alleles were detected, with a mean PIC of 0.57, indicating the use of polymorphic and informative markers. The population structure analysis with the Bayesian (STRUCTURE v 2.3.4) and grouping methods (Neighbor- joining and PCoA) indicated three discrete population groups with significant genetic differentiation of 22% (AMOVA - Fst; p<0.001). It highlighted the finding of nineteen different genotypes, suggesting the presence of a high number of duplicate materials that will have to be evaluated for the possible elimination of redundant resources in the germplasm bank. [ABSTRACT FROM AUTHOR]

Los parámetros poblacionales son fundamentales cuando un nuevo recurso se incorpora a la canasta pesquera. En el noroeste del Golfo San Matías, Ameghinomya antiqua comenzó a ser recolectada con fines comerciales. El objetivo de este trabajo fue analizar la estructura poblacional y describir el crecimiento individual de ejemplares de A. antiqua de dos poblaciones locales (El Sótano y Playa Villarino) previo al inicio de su explotación. Los organismos de estas poblaciones difirieron en tallas y pesos de valvas, tanto en la estructura general como en las medidas de tendencia central. Las estructuras de edades también resultaron disímiles: El Sótano presenta individuos longevos (mayores a 18 años) mientras que Playa Villarino está caracterizada por individuos jóvenes, menores a 15 años. La especie presenta un crecimiento acelerado durante los primeros años, alcanzando 90% de la talla máxima a los 5 años. La edad máxima estimada fue de 26 años. El alto asintótico fue mayor en Playa Villarino (56,56 mm) que en El Sótano (53,03 mm). Estas poblaciones poseen características biológicas y poblacionales que sugieren que podría realizarse un manejo sustentable de esta especie al incorporarse a la canasta de recursos bentónicos de la flota artesanal del Golfo San Matías.

The queen conch, Aliger gigas is a large marine gastropod mollusc that inhabits shallow seagrass meadows and sandplain habitats throughout the Caribbean. Owing to overfishing and degradation of the environment, it has become an endangered species in most of its habitat. Research on Cuban populations of A. gigas is scarce and mostly focused on conch exploitation. The present study assesses, for the first time, the genetic diversity and population structure of A. gigas from six locations on the Cuban platform, using five microsatellite loci. At most of the sampled locations, the observed heterozygosity was lower than expected and the F IS value was significantly positive, both of which suggest inbreeding. Also, we found evidence of bottlenecks for two of the locations with a deficit of heterozygotes. Although statistically significant, only 1.66% of the total variance was explained by genetic differentiation among populations, and discriminant analysis of principal components showed different degrees of overlapping between all locations. Accordingly, the results showed that there is an extensive and symmetrical exchange of genetic information. Sparse non-negative matrix factorization analysis determined the existence of three ancestral populations admixed across the sampled locations. Thus, our results suggest that A. gigas from the Cuban island platform could be a unique population, which is relevant for management and conservation strategies. [ABSTRACT FROM AUTHOR]

One of the objectives of maize breeding programs is to develop inbred lines of high genetic value, which, when crossed, can produce hybrids with superior agronomic characteristics. In Colombia, obtaining hybrids is of great interest since they can help increase maize yield and production, bridging the gap between national production and the current 74% maize import. Semillas Valle S.A. is a colombian company with a hybrid maize breeding program focused on the tropical and subtropical zones. Currently, Semillas Valle S.A.'s maize breeding program lacks a characterization of the germplasm that would allow the establishment of efficient strategies to obtain high- yielding hybrids. In this study, the classification of inbred lines into heterotic groups was carried out based on genomic data using SNP molecular markers and phenotypic variables from 66 inbred lines, and field data from a diallel trial involving 30 parental inbred lines. From a cluster analysis of SNP data, three subpopulation groups were identified. On the other hand, the results of the diallel allowed the classification of lines into three groups based on general combining ability for multiple traits (HGCAMT). However, the integration of these methodologies could provide more information regarding the heterotic groups present in the evaluated population. [ABSTRACT FROM AUTHOR]

This study deals with the genetic characterisation of the dog Ca Rater Mallorquí, whose former function was hunting small mammals. The aim of this study is to analyse the within and between breed genetic diversity and genetic differentiation by comparing this population with other breeds with the same geographical distribution and functional characteristics. Thirty-three microsatellites recommended by the International Society of Animal Genetics (ISAG) were analysed in 79 samples. The betweenbreeds genetic diversity study was carried out with data obtained from 275 samples of 5 Balearic dog breeds: Ca Mè Mallorquí, Ca de Bou, Ca de Bestiar, Ca de Conills de Menorca and Ca Eivissenc (Podenco Ibicenco). The population has not a significant deviation from Hardy-Weinberg equilibrium, with an HO of 0.656 and an HE of 0.685. The FST statistic showed that 13,10% of the genetic differentiation is due to between-breed differences. The analysis of the genetic structure clearly showed the differentiation of the Ca Rater Mallorquí from the rest of breeds, without any evident signs of substructure. In conclusion, the Ca Rater Malloquí presents a high genetic diversity, it is a defined and genetically homogeneous breed that shows no signs of crossbreeding with the rest of the breeds included in the study. These results provide essential knowledge of the genetic situation of the Ca Rater Mallorquí and constitute a starting point for the design and implementation of a conservation plan for the breed. [ABSTRACT FROM AUTHOR]

Copyright of Runa: Archivo para las Ciencias del Hombre is the property of Runa: Archivo para las Ciencias del Hombre and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

La presente investigación consiste en un estudio de caso con el objetivo de describir el comportamiento histórico de la estructura poblacional en las provincias de El Oro, Loja y Zamora Chinchipe, que conforman la Región Sur de Ecuador, durante el periodo 1962-2010 y comprender el proceso de envejecimiento. La investigación se basó en la información oficial de los censos de población y vivienda, y se emplearon las variables población general, sexo, área geográfica, ciclos de vida, índices de infancia, juventud, generacional de ancianos, de vejez y de sobreenvejecimiento poblacional. Para determinar el ritmo de crecimiento se calculó la tasa de crecimiento anual geométrica, y para el envejecimiento, las medias, medianas y cuartiles poblacionales. La población de la Región Sur del Ecuador envejeció en 7,6 años, con variaciones significativas a nivel de las provincias: en El Oro envejeció 8,1 años, en Loja, 7,6 años, y en Zamora Chinchipe, 4,5 años. El análisis por ciclos de vida muestra escenarios disímiles que sirven como contexto de los procesos de salud, enfermedad y mortalidad, a pesar que no aborda toda la dinámica poblacional. En general, se evidencia una transición demográfica compleja, asimétrica, en espacios político-geográficos heterogéneos, en donde se han generado históricamente procesos de reproducción biológica-social interrelacionados, pero al mismo tiempo, disímiles.

This study deals with the genetic characterisation of the dog Ca Rater Mallorquí, whose former function was hunting small mammals. The aim of this study is to analyse the within and between breed genetic diversity and genetic differentiation by comparing this population with other breeds with the same geographical distribution and functional characteristics. Thirty-three microsatellites recommended by the International Society of Animal Genetics (ISAG) were analysed in 79 samples. The between-breeds genetic diversity study was carried out with data obtained from 275 samples of 5 Balearic dog breeds: Ca Mè Mallorquí, Ca de Bou, Ca de Bestiar, Ca de Conills de Menorca and Ca Eivissenc (Podenco Ibicenco). The population has not a significant deviation from Hardy-Weinberg equilibrium, with an HO of 0.656 and an HE of 0.685. The FST statistic showed that 13,10% of the genetic differentiation is due to betweenbreed differences. The analysis of the genetic structure clearly showed the differentiation of the Ca Rater Mallorquí from the rest of breeds, without any evident signs of substructure. In conclusion, the Ca Rater Malloquí presents a high genetic diversity, it is a defined and genetically homogeneous breed that shows no signs of crossbreeding with the rest of the breeds included in the study. These results provide essential knowledge of the genetic situation of the Ca Rater Mallorquí and constitute a starting point for the design and implementation of a conservation plan for the breed. [ABSTRACT FROM AUTHOR]

In 2004, Xiphopenaeus kroyeri, one of major species in commercial fisheries in Brazil was included in the list of brazilian overfished species and, in 2006, two cryptic species were identified in the Atlantic Ocean by molecular approaches: Xiphopenaeus sp. I and II. In 2019, Carvalho-Batista et al. described both Xiphopenaeus sp. I and Xiphopenaeus sp. II and these species were named X. kroyeri and X. dincao, respectively. This study aimed at performing morphometric analysis in order to identify potential fishing stocks of X. kroyeri sensu strictum along Brazilian coast. The results obtained separate Caravelas, Atafona and Balneário Camboriú from all the other populations studied and showed three groups: Ubatuba, Nova Almeida; Ubatuba, Cananéia; Ubatuba, Santos. These results indicate that the maritime limits practiced in closed seasons along Brazil are embracing the detected morphometric stock boundaries observed for Xiphopenaeus kroyeris.s. [ABSTRACT FROM AUTHOR]

Introduction: Tree ferns are significant components of temperate, tropical and subtropical forests, contributing to shape complex forest stand structures. Objectives: 1) to describe the population structure of Cyathea costaricensis in a remnant cloud forest of Westcentral Mexico; 2) to characterize and relate the floristic composition and the structure of the most important tree species associated to the C. costaricensis population and; 3) to describe the environment where C. costaricensis occurs. Methods: We estimated the Importance Value Index (IVI) to select the most important canopy-dominant species associated to C. costaricensis; we constructed height and Diameter at Breast Height (DBH) frequency distributions for those selected species according to IVI as well as for C. costaricensis population; we computed the asymmetry of the frequency distributions through the coefficient of skewness and the probability density function via the Kernel density estimation. We tested for differences between canopy-dominant tree species and C. costaricensis population structure by the non-parametric Wilcoxon rank sum test. Results: C. costaricensis individuals presented the smallest heights and intermediate DBH sizes as compared with the canopy-dominant species, with statistically significant differences for height but not for DBH according to the Wilcoxon test. Most of the tree fern individuals were located in uneven terrains and over the base slope of the terrain; canopy openness and Total Radiation Under the Canopy values were similar to those reported for Cyathea species elsewhere. Conclusions: We confirm the hypothesis of comparable structure between the canopy-dominant species and the C. costaricensis population only for DBH; on the contrary, for trunk height, there were statistically significant differences; the small heights of C. costaricensis suggest their coexistence in the understory through sheltering from the taller canopy-dominants. Mostly all individuals of C. costaricensis were confined to local environmental conditions, particularly to physiography. [ABSTRACT FROM AUTHOR]

Habitat fragmentation and the associated landscape connectivity loss can reduce gene flow among populations, which could lead to a decrease in genetic variability, and an increase in the extinction risk of a species. The main goal of this study was to provide genetic diversity and population structure data for Pampas foxes from the southern Argentine Espinal ecoregion. Through the analyses of 30 tissue samples collected during 2013-2018, we were able to genotype 23 individuals at 18 microsatellite loci. Results indicate high diversity values, and exhibiting an average of 10 alleles per locus (min= 6, max= 13), 0.71 (range= 0.35-0.91) of mean observed heterozygosity and 0.83 (min= 0.61, max= 0.91) of mean expected heterozygosity. Bayesian analyses suggest no population structure. Finally, we did not detect a pattern of isolation by distance. The high habitat adaptability and the generalist feeding behavior of Pampas fox may explain our findings, which are in agreement with the general patterns described for other fox species. The panel of microsatellites employed in this study proved to be suitable for Pampas fox genotyping and it can be used in further genetic assessments needed to validate and expand our understanding of its population genetics. [ABSTRACT FROM AUTHOR]

Examining differences among recently diverged populations can provide insight into the traits and evolutionary mechanisms that drive or maintain divergence. The genus Sturnella includes 2 recently diverged species, Sturnella magna (Eastern Meadowlark) and S. neglecta (Western Meadowlark), the former of which has a complex of subspecies distributed across the Americas. Of the S. magna subspecies that occur in the United States, S. m. lilianae is the only one with a disjunct range, occurring in the southwestern United States and central Mexico. It also has markedly different song patterns than all other S. magna subspecies. In order to assess population differentiation, we performed whole-genome sequencing of 35 birds and analyzed song characteristics from 85 birds. Songs from each species and S. m. lilianae were diagnosable using linear discriminant function analysis and support divergence in song between all taxa. Phylogenetic analysis and admixture proportions support 3 distinct clades within North American meadowlarks, and tests of introgression failed to detect a significant signal. Overall, our results indicate that S. m. lilianae exhibits high levels of genetic and vocal differentiation from both S. magna and S. neglecta, with no evidence of introgression between any group, and forms a distinct evolutionary lineage. We thus recommend the elevation of S. m. lilianae to species status. [ABSTRACT FROM AUTHOR]

En la Argentina, la Ecorregión Pampeana presenta bajo nivel de protección debido a su alto valor económico y al dominio privado. El reemplazo de sus ambientes naturales por usos productivos causó la retracción numérica de especies como el carpincho (Hydrochoerus hydrochaeris), que habita sus humedales. Los aspectos biológicos y ecológicos de esta especie permanecen poco estudiados en la provincia de Buenos Aires. En consecuencia, los objetivos de este estudio fueron estimar las abundancias real y relativa, la densidad y el tamaño poblacional, y determinar la estructura de la población, el patrón de actividad de los individuos en las dos lagunas presentes en el área natural protegida “El Morejón”, partido de Campana, Buenos Aires. Para ello, a lo largo del año 2014 se realizaron relevamientos de transectas de rastros y trampas cámara en las cuatro estaciones. A pesar de estar inmersa en un área urbanizada e industrializada, se obtuvo un tamaño poblacional mayor al esperado. Se estimó la presencia de un promedio de 15 individuos en la Laguna 1 y 154 en la 2, en áreas de uso estimadas de 3 y 10 ha, respectivamente. Durante el invierno se registró el mayor número de individuos, y en otoño, primavera y verano, los menores. Es posible que esto se asocie a la movilidad de los individuos en busca de alimento. Estos resultados son relevantes para una planificación correcta de medidas de manejo, y confirman la importancia de que existan reservas privadas que conserven el ecosistema natural de la región.

Heterotheca subaxillaris (Lam.) Britt. & Rusby, falso alcanfor, es una maleza anual perteneciente a la familia Compositae, originaria de los Estados Unidos. El objetivo de este trabajo fue establecer su distribución y evaluar la estructura de una población a partir de la densidad por estados fenológicos. El estudio se realizó a dos distintas escalas: distribución a escala regional, dentro de la provincia de La Pampa (Argentina) y el seguimiento a campo de la especie a escala de parcela, para el registro fenológico y densidad. H. subaxillaris se halla principalmente distribuida en la zona noreste de la provincia (zona de mayor aptitud agrícola), disminuyendo hacia el suroeste, encontrándosela predominantemente sobre suelos franco-arenosos a arenosos. La germinación de los aquenios fue principalmente otoñal y el crecimiento y desarrollo, primavero-estival. Dentro de los estados fenológicos la fase más sensible fue la de transición de plántula a roseta, debido a la elevada mortalidad de las plántulas. Este estado fue el más prolongado y coincidente con las condiciones ambientales más adversas. El éxito de pasaje del estado vegetativo al reproductivo fue del 25% para la densidad de rosetas y del 2% para el de plántulas.

Copyright of Revista Mundo de Antes is the property of Revista Mundo de Antes and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Ecologia Austral is the property of Asociacion Argentina de Ecologia and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Carnivores are decreasing globally due in part to anthropogenic ecological disturbances. In Argentina, human activities have fragmented wildlife habitat, thereby intensifying puma–livestock conflict and leading to population control of the predator species by hunting. We investigated genetic variability and population structure of pumas (Puma concolor) from three south-central Argentine provinces with two different management policies for the species: full protection versus legal hunting. All genetic estimates were based on 83 individuals genotyped at 25 species-specific microsatellite loci. The overall genetic diversity was high (observed heterozygosity = 0.63), but lower than in other South American populations. Spatial analyses revealed the presence of two bottlenecked genetic clusters with very similar diversity and low gene flow (3% per generation) between them. However, analyses based on a priori separated groups showed that gene flow follows increasing values of hunting pressure, converging to the area with the greatest number of individuals harvested. Our results suggest that hunting pressure likely is contributing to the gene flow pattern, limiting pumas' movements and creating a metapopulation dynamic among geographic subpopulations. Integrated demographic and genetic approaches are needed to better understand pumas' movements across the landscape and adopt successful management plans to achieve long-term population viability. [ABSTRACT FROM AUTHOR]

El borrego cimarrón del desierto (Ovis canadensis) es una especie con una distribución espacial restringida, debido a que requiere de características específicas de hábitat que le provean agua, alimento, cobertura y espacio; factores determinantes en la selección de sitios de distribución. O. c. weemsi tiene el estatus de especie Sujeta a Protección Especial y, actualmente, solo se ha registrado en algunas zonas de Sonora, Baja California y Baja California Sur. La Isla El Carmen, Baja California Sur, pertenece al Parque Marino Nacional Bahía de Loreto, por su ubicación geográfica, condiciones climáticas, escasez de agua, tipos de vegetación y topoformas es un sitio de enorme interés para realizar investigaciones en ecosistemas de zonas áridas. Se determinó la distribución del borrego cimarrón (O c. weemsi) introducido en la Isla, mediante el método de conteo por franjas, modificado por Hayne; y el registro a través de avistamiento de ejemplares en los aguajes, para reforzar las observaciones de la estructura poblacional de la especie. Asimismo, se registraron la inclinación del terreno, época del año, distribución de aguajes y presencia de comederos para determinar su efecto en la estructura de la población. Se estimó una densidad de 4.96 borregos km-2, con un total de 1 151 observaciones. Se calcularon 616 individuos en una superficie de 12 428 ha con matorral desértico sarcocaule.

Background: Romosinuano cattle breed in Mexico has endured isolation and it is necessary to characterize it in order to facilitate sustainable genetic management. Objective: To assess the evolution of the structure and genetic diversity of the Romosinuano breed in Mexico, through pedigree analysis. Methods: Pedigree data was obtained from Asociación Mexicana de Criadores de Ganado Romosinuano y Lechero Tropical (AMCROLET). The ENDOG program (4.8 version) was used to analyze two datasets, one that includes upgrading from F1 animals (UP) and the other with only straight-bred cattle (SP). For both datasets, three reference populations were defined: 1998-2003 (RP1), 2004-2009 (RP2), and 2010-2017 (RP3). The pedigree included 3,432 animals in UP and 1,518 in SP. Demographic parameters were: Generation interval (GI), equivalent number of generations (EG), pedigree completeness index (PCI), and gene flow among herds. Genetic parameters were: Inbreeding (F) and average relatedness (AR) coefficients, effective population size (Nec), effective number of founders and ancestors, and number of founder genome equivalents. Results: The GI varied from 6.10 to 6.54 for UP, and from 6.47 to 7.16 yr for SP. The EG of the UP and SP improved >63% from RP1 to RP3. The PCI increased over time. No nucleus or isolated herds were found. For RP3, F and AR reached 2.08 and 5.12% in the UP, and 2.55 and 5.94% in the SP. For RP3, Nec was 57 in the UP and 45 in the SP. Genetic diversity losses were attributed mainly (>66%) to genetic drift, except for RP3 in the SP (44%). Conclusions: A reduction of the genetic diversity has been occurring after the Romosinuano breed association was established in Mexico, and this is mainly due to random loss of genes. [ABSTRACT FROM AUTHOR]

Copyright of Revista de la Academia Colombiana de Ciencias Exactas, Físicas y Naturales is the property of Academia Colombiana de Ciencias Exactas, Fisicas y Naturales and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Journal de Ciencia e Ingeniería is the property of Corporacion Universitaria Autonoma del Cauca and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

The genetic variability of 96 accessions of oil palm (E. guineensis Jacq.) from Cameroon and Zaire with 20 microsatellite markers was determined. 59 alleles were detected with an average of 2.95, three loci were polymorphic with a PIC (Polymorphic Information Index) average 0.58. High genetic diversity, with a total heterozygosity of 0.46, and a high percentage of polymorphic loci of 90% was found. FST value was of 0.14, suggesting that in the populations of Cameroon and Zaire there is a moderate population structure. The observed heterozygosity (Ho = 0.67) was higher than expected heterozygosity (He = 0.42), demonstrating a low presence of homozygous. The parameters of population differentiation as the FIS and FIT confirmed a high number of heterozygotes with respect to expected under the conditions of Hardy-Weinberg equilibrium. Microsatellite allowed discriminating genotypes according to the origin place. The results obtained show that the collections of Cameroon and Zaire may be considered as a single population, with moderate population structure despite of the constant existent gene flow. These results could be used in future conservation programs, selection and genetic improvement of the species.

Introducción: la ardilla Sciurus variegatoides es una de las especies más abundantes de ardilla en América Central, sin embargo, poco se sabe sobre su reproducción. Objetivo: determinar el ciclo reproductivo de S. variegatoides en un área agrícola de Costa Rica. Métodos: mensualmente (diciembre de 1986 a enero de 1988) recolecté 10 animales en Hacienda Curú, Paquera, Costa Rica. Usé la presencia de escroto, el tamaño de los testículos y la longitud de los cuernos uterinos para evaluar la madurez. El ciclo reproductivo se basó en la preñez, la lactancia, el cortejo, la construcción de nidos y la proporción de subadultos. Resultados: recogí un total de 135 ardillas, la proporción de sexos fue de 1,7 machos por cada hembra y el 22% fueron subadultos (ambos sexos). Capturé las hembras embarazadas de diciembre a junio y representaron el 42% de las hembras adultas. Febrero y abril estuvieron marcados por cortejo y un aumento en la construcción de nidos. Recolecté las hembras lactantes de junio a setiembre, cuando capturé más subadultos. Conclusión: no hubo evidencia de actividad reproductiva en octubre y noviembre.

RESUMEN La mortalidad por pesca ha sido pocas veces estudiada aislando el efecto causado por las capturas. En este estudio se analizó este aspecto usando como modelo biológico al camarón fantasma Callichirus major (Say, 1818), el cual es colectado intensamente en varias regiones de la costa de Brasil. Para ello, la densidad de las galerías y la demografía poblacional de C. major fue analizada en las playas de Gonzaga e Itararé, dos playas contiguas del Estado de São Paulo, Brasil. La playa de Gonzaga fue considerada como control debido a que desde 1992 una ley municipal impide las capturas de C. major, mientras que Itararé fue considerada como tratamiento ya que en este lugar este camarón es recolectado durante todo el año. Los resultados mostraron que la densidad de las galerías y el tamaño de las hembras fueron significativamente mayores en la playa de Gonzaga que en Itararé. En Itararé, la proporción sexual no mostró diferencias significativas de la relación 1:1, lo cual no se ajustó a lo observado en el área sin mortalidad por pesca y al patrón general reportado en otras especies de camarones fantasma del mundo en donde las hembras predominan sobre los machos. El potencial reproductivo fue significativamente menor en Itararé, como efecto del menor número de hembras presentes en esta área sometida a la pesca intensiva de camarones. De acuerdo con una estimativa inicial, un 71% de los individuos murieron por efecto de la pesca en Itararé. Esto hace inviable el sostenimiento ambiental de C. major en esta área dada la actual presión de extracción. La presencia de C. major en la playa de Itararé y probablemente en otras áreas próximas donde es capturada, estaría favorecida por el permanente suministro de larvas procedentes de la playa de Gonzaga, en Santos, que está protegida por ley y fiscalización municipal.

Los flujos migratorios que se vienen produciendo desde fi nales del siglo pasado e inicios del presente, provenientes de la Subregión Andina a España, han marcado un hito de trascendental importancia entre ambos contextos, uno en vías de desarrollo y otro desarrollado. La transición demográfi ca al confi gurar estructuras etarias específi cas en cada uno de estos contextos según los niveles de descenso en la fecundidad y la mortalidad alcanzados, ha dado lugar a dos fenómenos demográfi cos importantes; por un lado, al surgimiento del bono demográfico en los países de la Subregión Andina; por el otro, al envejecimiento poblacional en España. Se ha planteado como hipótesis que los flujos migratorios que se originan en los países de la Subregión Andina donde el bono demográfico (al no ser aprovechado ocupándolo como mano de obra) tiende a migrar hacia los lugares donde puede insertarse en el mercado ocupacional, con lo que dinamizará la estructura etaria envejecida del país de destino, en este caso España.

La palma Sabal mauritiiformis es un recurso importante en el Caribe colombiano debido al uso de sus hojas para techar. Para evaluar el estado de sus poblaciones en Piojó (Atlántico), uno de los municipios más productores de hojas, se estudió la densidad y la estructura poblacional de la palma. Se establecieron 16 parcelas de 0,1 ha, en los tres sistemas de uso de suelo más comunes en la zona: ganadería (6), cultivos (5) y rastrojo (5). Se encontró que la palma amarga constituye un recurso silvestre, muy resistente y capaz de adaptarse a ambientes perturbados pues está incorporada en sistemas productivos de cultivos, rastrojos y ganadería, donde las prácticas de manejo influyen en la densidad y estructura de sus poblaciones. La palma es muy resistente y capaz de adaptarse a ambientes perturbados. El área estudiada incluyó 5349 individuos distribuidos en cuatro categorías de tamaño. Los rastrojos (3620 ± 2808 individuos/hectárea) y los cultivos (5612 ± 3361 ind/ha) presentaron más individuos y mejores estructuras poblacionales que las áreas de ganadería (1488 ± 827 ind/ha), en las cuales se encontraron poblaciones más deterioradas por efecto del pisoteo y el forrajeo. La prevalencia de individuos en algunas clases de tamaño refleja las condiciones de manejo actual e histórico; actividades como el pastoreo o las quemas, sin una apropiada planificación, pueden comprometer el desarrollo de las poblaciones de la palma y la futura disponibilidad del recurso.

Neohelice granulata inhabits estuarine and protected coastal areas in temperate regions and is the most dominant decapod crustacean in the Bahía Blanca Estuary, Argentina. The population structure was studied during a year in a SW Atlantic salt marsh located in the Bahía Blanca Estuary. Crabs were sampled monthly from August 2010 to July 2011. The maximum observed density was 30 crabs m-2 in February and 70 burrows m-2 in May. The maximum carapace width (CW) was 32 and 27.5 mm in males and females respectively. Medium size crabs were between 16 and 20 mm CW. Significantly smaller sized crabs were observed at the lower intertidal regions (P < 0.05). The sex ratio was favorable for males and was significantly different from the expected 1:1 (P < 0.05). The recruitment of unsexed juveniles crabs (CW

Copernicia tectorum is a palm that grows in large populations on seasonally flooded savannas in the Caribbean region of Colombia, where its stems and expanded leaves are used in construction, and its unexpanded leaves are used to make handicrafts. We studied abundance and population structure in 34 plots of 20×10m (0.68 ha) of three localities (Plato, Córdoba and Magangué) at the Mompox Depression, an inner delta formed by the confluence of four large rivers. We recorded growth and mortality of 164 palms of different size classes over 13 months, and additionally we estimated seedling and juvenile mortality in two 10x10m plots within the same sites. Data analysis using Kolgomorov-Smirnov (KS), Kruskal-Wallis and Mann-Whitney tests were made on Statgraphics Plus and SPSS. We related the structure and dynamics of the palm stands to flood intensity. Copernicia tectorum has the fastest leaf production rate recorded for any palm (19-23 leaves/year in subadults and adults), and a short life span of ca. 46 years. The abundance, density and high leaf production rate of this palm offer a great potential for the sustainable use of its unexpanded leaves (especially at Plato, where there are ca. 480ha of palm stands with 300-1 000 individuals/ha), as leaf harvest from subadult and adult individuals does not appear to affect population structure. The palm is a pioneer of the flood plain, and the palm stands at particular sites appear to wax and wane following sedimentation dynamics, in which the species plays in important role. Current population structure and the scarce recruitment of juveniles at the study site suggest that the population is waning in that site. Management actions should be taken to reestablish natural river dynamics at the lagoon complex where the palm grows. Appropriate management of palm stands may contribute to minimize any negative effects of river dynamics.

Copyright of Iheringia. Série Zoologia is the property of Fundacao Zoobotanica do Rio Grande do Sul and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Abstract: Landscape‐scale alterations that accompany urbanization may negatively affect the population structure of wildlife species such as freshwater turtles. Changes to nesting sites and higher mortality rates due to vehicular collisions and increased predator populations may particularly affect immature turtles and mature female turtles. We hypothesized that the proportions of adult female and immature turtles in a population will negatively correlate with landscape urbanization. As a collaborative effort of the Ecological Research as Education Network (EREN), we sampled freshwater turtle populations in 11 states across the central and eastern United States. Contrary to expectations, we found a significant positive relationship between proportions of mature female painted turtles ( Chrysemys picta) and urbanization. We did not detect a relationship between urbanization and proportions of immature turtles. Urbanization may alter the thermal environment of nesting sites such that more females are produced as urbanization increases. Our approach of creating a collaborative network of scientists and students at undergraduate institutions proved valuable in terms of testing our hypothesis over a large spatial scale while also allowing students to gain hands‐on experience in conservation science. [ABSTRACT FROM AUTHOR]

The crevalle jack Caranx hippos, has a wide distribution in the Western Atlantic, becoming one of the most economically important species in the artisanal fishing industry in Colombia. However, little is known about its biology. The present study aimed to evaluate the variation and genetic structure of C. hippos in the Colombian Caribbean by analyzing the mitochondrial DNA region control and cytochrome oxidase subunit (COI). We sequenced the DNA of 153 muscle samples collected from specimens obtained from six fishing ports. The results showed 21 haplotypes for COI and 116 haplotypes for the control region, divided into two lineages that do not exhibit a pattern of geographical distribution. For mitochondrial control region, the estimated haplotype diversity (Hd) presented relatively high values (Hd= 0.99 and = 0.1), while for COI results were Hd = 0.68 and = 0.01; the relationship between haplotype and nucleotide diversity and the neutrality test revealed that C. hippos experienced bottlenecking and a subsequent rapid population expansion. Estimates of genetic structure were low and insignificant, indicating no differentiation between samples collected from geographical isolation. This suggests that for the Colombian Caribbean there is a panmictic population of C. hippos. However, variations were found at population levels, especially in La Guajira, Turbo and San Antero, which, when compared to those included for Brazil and México, demonstrated that unique haplotypes in La Guajira are more aligned to the Brazilian populations, by means of the influence of the Caribbean Current, whilst those from Turbo and San Antero are more frequent in haplotypes originating from Mexico. Future studies should focus the understanding of these processes. Rev. Biol. Trop. 66(1): 122-135. Epub 2018 March 01. [ABSTRACT FROM AUTHOR]

Copyright of Revista Mexicana de Biodiversidad is the property of Universidad Nacional Autonoma de Mexico, Instituto de Biologia and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

En este estudio se analizaron los niveles de diversidad y estructura genética de 161 cerdos domésticos pertenecientes a tres poblaciones del departamento de Córdoba, mediante 20 marcadores microsatélites. Todos los microsatélites utilizados resultaron polimórficos. Para todos los loci , el valor promedio de la heterocigosidad esperada fue mayor al valor promedio de la heterocigosidad observada, lo cual puede sugerir una posible endogamia en el sistema de apareamiento. e l índice F s T (0,12 ± 0,08) mostró un 88% de la varianza en las frecuencias alélicas reportadas dentro de cada población y solo el 12% de la varianza atribuible a diferencias entre poblaciones. Los valores de F is (0,079) y F i T (0,13), indican deficiencia de heterocigotos dentro de cada población y a nivel global. d esviaciones significativas del equilibrio Hardy-Weinberg ( p < 0,05) fueron observadas en ocho de los marcadores utilizados. e l árbol n eighbor-Joining obtenido reveló que Momil estuvo más estrechamente relacionada con Cereté, mientras Tierralta se mostró más alejada. e l análisis de componentes principales ( a CoP) genera la individualización geográfica de cada población, siendo distante la población de Tierralta de las poblaciones Momil y Cereté, resultados similares a los obtenidos con la metodología n eighbor-Joining. e l programa s tructure con un K = 3, confirma la existencia de tres grupos o poblaciones distintas, generándose un patrón filogeográfico observado en la relación entre Momil, Cereté y Tierralta. e s importante señalar que son 3 grupos raciales diferentes, valiosos y deben conservarse.

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.

La abundancia y estructura poblacional son pará-metros importantes para evaluar y comparar el estatus de conservación de una población a través del tiempo en un área determinada. Este estudio describe la abundancia y estructura poblacional de Crocodylus acutus en la laguna Palmasola, Oaxaca. El trabajo consistió en recorridos nocturnos, entre las 21 y 24h, durante la fase de luna nueva para contabilizar el número de individuos y obtener estimaciones poblacionales. El tamaño poblacional estimado fluctuó de 32.7 a 93 individuos según el modelo utilizado. Las tasas de encuentro registradas fluctuaron de 32 a 109.3 ind/km lineal durante los 40 recorridos efectuados con un tiempo promedio de navegación de 18 minutos. Existió una marcada dominancia de la clase III (subadultos), seguido por la clase II y en menor proporción las clases IV y V, así como aquellos individuos en los que no se pudo determinar el tamaño corporal, en ambas épocas del año. Mientras tanto, los individuos juveniles (Clase II) se observaron en mayor proporción asociados al manglar que cubre las orillas del cuerpo de agua (26.1%), los individuos subadultos (Clase III) a menudo se observaron sobre el espejo de agua sin vegetación flotante (22.7%) y entre el manglar que cubre las orillas del cuerpo de agua (15.7%), mientras que los ejemplares adultos se observaron con mayor frecuencia sobre el espejo de agua sin vegetación flotante (9.7%). Con la presente información se contribuye al conocimiento de la ecología poblacional de C. acutus en la laguna Palmasola donde el tamaño poblacional estimado parece mostrar valores altos con respecto a lo reportado en otros estados de la República Mexicana.

Cittarium pica is a conspicuous gastropod of the rocky coastlines of the Caribbean. Given its importance in the diet of Caribbean communities, it has been over-exploited, even reaching extinction in some places and the species has been included in the red lists of marine invertebrates in some countries. Its fishery in San Andres Island-Colombia is artisanal without any regulation, leading to a decrease in its population. Taking into account the socio-economic, cultural and ecological importance of C. pica and its vulnerability to extinction, it is urgent to develop management actions directed to increase the resilience of the species and its sustainability as a fishery resource. To assess the current population state of C. pica from San Andrés Island, we estimated size structure, sex structure, maturation size and growth parameters, based on length-frequency data analysis. From September to December 2013, and January to March 2014, we randomly collected 458 individuals at eight representative sites of the rocky shores of the island. We measured the longest diameter of the shell base, determined the sex by the color of the gonad and thus determined the minimum maturation size. We found, that 80 % of the population consisted of small individuals < 25.5 mm sizes. The sex ratio was 1:1 except in November, where males were more abundant. The minimum size at the beginning of maturity for both sexes was 14.07 mm. The growth parameters of von Bertalanffy: K (0.730 yr-1), L∞ (110.78 mm) and Φ (3.95) were higher when compared to other populations of the Caribbean. The total mortality was 3.39 yr-1, while natural and fishing mortalities were 1.02 yr-1 and 2.36 yr-1, respectively. The maximum annual recruitment pulse was estimated for June and the maximum exploitation rate for a sustainable yield was between 0.563 and 0.640, when the catch size was greater than 40 mm or 50 mm, respectively. The exploitation rate was estimated in 0.70, suggesting a strong extractive resource pressure. With these results we recommend the closure of the fishery and constant monitoring to promote and the population recovery is verified. Until a monitoring shows that the population recovers on the island. [ABSTRACT FROM AUTHOR]