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Los capibaras son los roedores más grandes del mundo, sin embargo, no se han realizado estudios genético poblacionales exhaustivos con ellos. En el presente trabajo se analizó la estructura genética de una manada de 31 capibaras (Hydrochoerus hydrochaeris) muestreada en Hato Corozal, Departamento de Casanare en los Llanos Orientales de Colombia, mediante cinco marcadores microsatelitales. La diversidad genética se determinó en 0.61 y un número promedio de alelos de 5.2, lo cual se puede considerar medio-bajo para este tipo de marcadores. De los cinco marcadores empleados, tres mostraron proporciones genotípicas en concordancia con lo esperado en equilibrio Hardy-Weinberg, mientras que un marcador mostró un exceso significativo de homocigotos y otro un exceso significativo de heterocigotos. No se encontraron diferencias significativas para esos cinco marcadores entre machos y hembras de la manada muestreada. La aplicación de diferentes procedimientos para detectar posibles cambios demográficos históricos (expansiones poblacionales o cuellos de botella) mostró claramente que la población analizada ha pasado por un cuello de botella extremadamente fuerte en épocas recientes. La limitada variabilidad genética encontrada y la fuerte evidencia de que la manada estudiada ha pasado por un cuello de botella reciente es probablemente el resultado de la cacería ilegal.Genetic structure of a group of capybaras, Hydrochoerus hydrochaeris (Rodentia: Hydrocheridae) in the Colombian Eastern Llanos. The capybaras are the biggest rodents in the world but, however, there are not extensive population genetics studies on them. In the current work, we studied the genetic structure of a troop of 31 capybaras (Hydrochoerus hydrochaeris) sampled in Hato Corozal, Casanare Department at the Colombian Eastern Llanos, by means of five microsatellite markers. The gene diversity was 0.61 and the average allele number was 5.2, which is a medium-low level for markers of this nature. Out five markers employed, three were in Hardy-Weinberg equilibrium meanwhile one showed a significant homozygote excess and other presented a significant heterozygote excess. There were not significant genetic differences between males and females inside this troop. The application of different procedures to determine possible historical demographic changes (population expansions or bottlenecks) clearly showed that the population analyzed crossed over a very narrow recent bottleneck. The illegal hunt is the possibly cause of this strong genetic bottleneck. Rev. Biol. Trop. 59 (4): 1777-1793. Epub 2011 December 01.

Los actinomicetos son importantes en la sostenibilidad de sistemas naturales. Su diversidad fue evaluada en suelos de bosque, pastizal y rastrojo, y dos profundidades en el Sur del Trapecio Amazónico Colombiano. Se analizaron suelos de cinco repeticiones por cobertura para un total de 15 unidades. Se tomaron seis muestras en cada unidad y dos profundidades, para un total de 30. Los actinomicetos cultivables se determinaron por recuento en placa, se extrajo ADN, se amplificó el gen ADNr 16s y su diversidad genética se estimó por ARDRA. Hubo diferencias de abundancia entre coberturas y profundidades, relacionadas con la vegetación, presencia de lombrices, macrofauna, altos niveles de materia orgánica, y bases totales. Se obtuvieron valores de diversidad fenotípica similares para las tres coberturas, pero los bosques son más diversos. Se identificaron 16 morfotipos, agrupados en séis géneros, siendo Streptomyces el más abundante. La heterogeneidad de los patrones ARDRA no permitió la asignación de especies, reflejándose variaciones en las secuencias de diferentes operones ADNr 16s en un mismo organismo. Las perturbaciones en la cobertura influyen sobre los actinomicetos, generando cambios en su abundancia y diversidad. Su importancia ecológica permite proponerlos como indicadores biológicos de alteración del paisaje.Communities of Actynomicetes fungy in three vegetation types of the Colombian Amazon: abundance, morphotypes and the 16s rDNA gene. Among soil microorganisms, Actinomycetes play an important role in the sustainability of natural and agricultural systems: decomposition of organic matter; degradation of recalcitrant compounds like lignin; nitrogen fixation; degradation of agricultural chemicals and biological control in plants and animals. We evaluated their diversity in soils under three different vegetation covers (pasture, tropical primary forest and stubble) at two depths in the Southern Colombian Amazon border. We collected five replicates per vegetation type (in each, three samples at 0-20cm and three at 20-30cm; for a total of 30 samples). Abundance and phenotypic diversity were determined by plate counting. Genomic DNA was extracted from the isolates: the 16s rDNA gene was amplified with specific primers, and its genetic diversity was estimated by means of an amplified restriction analysis (ARDRA). Actynomicetes abundance varied with vegetation and depth, possibly reflecting presence of earthworms, macro-fauna and physico-chemical characteristics associated to fertility, as well as organic matter, total bases, and optimal capacity to cationic interchange. Primary forests had the highest diversity. Sixteen morpho-types (six genera) were identified; Streptomyces was the most abundant everywhere. The heterogeneity of ARDRA patterns prevented species identification because of the intra-species variability in sequences of 16s rDNA operons. This community is a biological indicator of landscape alteration and could include new bio-active compounds of pharmaceutical interest. Rev. Biol. Trop. 57 (4): 1119-1139. Epub 2009 December 01.

Los programas de conservación de especies se apoyan fuertemente en estudios de genética poblacional. En el presente estudio, reportamos diversos análisis genéticopoblacionales en ocho especies de cérvidos neotropicales (Mazama americana, M. gouzaoubira, M. rufina, Odocoileus virginianus, Hippocamelus antisensis, Pudu mephistopholes, Ozotoceros bezoarticus y Blastoceros dichotomus) y, adicionalmente, en varias especies de cérvidos europeos y asiáticos (Cervus elaphus, C. nippon, Capreolus capreolus, C. pygargus and Dama dama). Una de esas especies europeas, la población de Cervus elaphus en Escocia, fue tomada como una población con un grado muy elevado de diversidad genética ya que proviene del cruce de diferentes grupos de ciervos rojos procedentes de diversas subespecies de la Europa continental. Desde una perspectiva de una diversidad genética depauperada, se tomó el nivel encontrado en una población de ciervos sika (Cervus nippon) en Escocia, que prácticamente no mostró variabilidad a nivel molecular. Respecto a esos dos casos que consideramos como de elevada y escasa variabilidad genética, encontramos que las poblaciones analizadas de Mazama americana, M. gouzaoubira y Odocoileus virginianus estuvieron cerca del límite máximo encontrado para el ciervo rojo escocés (H=0.64, 0.70 y 0.61, respectivamente), mientras que M. rufina mostró el más bajo grado de variabilidad genética de las especies neotropicales, cercano al extremo mínimo presentado por C. nippon. Algunas de las muestras de Mazama y de Odocoileus, tomadas a nivel macrogeográfico, mostraron un exceso de homocigotos debido, probablemente, a la existencia de efecto Wahlund (efecto de subdivisión). Ninguna de las especies analizadas parece haber atravesado un cuello de botella reciente.Genetic variability in Neotropical deer genera (Mammalia: Cervidae) according to DNA microsatellite loci. Species conservation programs are highly based on analyses of population genetics. We compared eight Neotropical Cervidae (Mazama americana, M. gouzaoubira, M. rufina, Odocoileus virginianus, Hippocamelus antisensis, Pudu mephistopholes, Ozotoceros bezoarticus and Blastoceros dichotomus) and some European and Asian Cervidae (Cervus elaphus, C. nippon, Capreolus capreolus, C. pygargus and Dama dama). The European species C. elaphus was our standard for a high degree of genetic variability: we used a Scottish population originated in the mix of diverse Western European subspecies. On the contrary, Cervus nippon (a population from Scotland with a founder effect) was our standard for a depauperated population. The M. americana, M. gouzaoubira and O. virginianus samples had high diversity values close to our C. elaphus population (H= 0.64, 0.70 and 0.61, respectively), while M. rufina was very low, close to C. nippon. Several sample sets of Mazama and Odocoileus yielded a homozygote excess, probably due to the Wahlund (subdivison) effect. There was no evidence of recent bottleneck events. Rev. Biol. Trop. 57 (3): 879-904. Epub 2009 September 30.

El presente trabajo muestra dos análisis moleculares sobre la filogenia de los cérvidos neotropicales. En uno se secuenció la región control del mtDNA (D-loop) de seis especies de Odocoileinae, utilizándose las secuencias de dos Muntiacinae como elementos externos. Se evidenciaron los siguientes resultados: La secuencia de una Mazama americana, de origen mexicano, presentó una fuerte relación filogenética con las diversas secuencias estudiadas de Odocoileus, contrario a lo esperado ya que, a priori, debería haberse asociado con las secuencias analizadas de otros ejemplares de Mazama de origen boliviano. Esto pone en evidencia que este género no es monofilético. A su vez, las secuencias de los ejemplares bolivianos de Mazama formaron una agrupación con secuencias de Pudu puda y O. bezoarticus. Una secuencia de O. virginianus, del área central de Colombia, presentó más relación con la secuencia de un O. hemionus norteamericano que con las restantes secuencias analizadas de O. virginianus, también de origen colombiano. Esto puede reflejar varias explicaciones hipotéticas, tales como la existencia de haplotipos ancestrales comunes entre ambas especies de Odocoileus, hasta la hibridación en Norteamérica entre ambos taxones antes de su penetración en Sudamérica. Los análisis de máxima parsimonia presentan una especial relación entre los Muntiacinae y el clado de los ciervos sudamericanos. El segundo análisis filogenético hizo uso de 16 marcadores nucleares microsatélites. Aunque, en principio, estos marcadores no son los más recomendables para estudios filogenéticos intergenéricos, los resultados muestran, al igual que el ADN mitocondrial, una mayor relación entre M. americana y O. virginianus que entre la primera especie y M. gouzaoubira.Phylogenetic relationships among Neotropical deer genera (Artiodactyla: Cervidae) by means of DNAmt sequences and microsatellite markers. The current work shows two molecular phylogenetic analyses on Neotropical deers. In the first analysis, the mitochondrial control region (D-loop) was sequenced in six Odocoileinae species from Latin America, using the sequences of two Muntiacinae as outgroups. The results obtained were as follows: A sequence of Mazama americana showed a striking relationship with several sequences of Odocoileus in contrast to that expected, since this M. americana haplotype, from a Mexican origin, was not associated with several Bolivian Mazama sequences analyzed. This could put forward that this genera is not monophyletic. On the other hand, these Bolivian Mazama formed a clade with Pudu puda and Ozotoceros bezoarticus. Likely, an Odocoileus virginianus sequence from the Central area of Colombia showed a more strong relationship with a Northamerican O. heminonus sequence than with the other O. virginianus sequences of Colombian origin as well. This could be explained by means of various different hypotheses. The first is the existence of common ancestral haplotypes between both species. Another one is the reiterative hybridization among both Odocoileus species before the migration of O. virginianus from North America to South America. Moreover, the maximum parsimony analysis showed an intense relationship between the Muntiacinae and this Neotropical Cervidae clade. In addition, and adding credence to the relevant polyphyletism found in Mazama by means of the mitochondrial control region DNA sequences, a second analysis with 16 DNA microsatellite loci also showed a higher genetic relationship between M. americana and O. virginianus, than between the first species regard to Mazama gouazoubira. Rev. Biol. Trop. 55 (2): 723-741. Epub 2007 June, 29.

Primates are one of more confiscated taxa by the environmental authorities in Bogota, Colombia. During 2008, 133 monkeys were confiscated; samples from 115 of them were sequenced by the mitochondrial cythocrome oxidase II gene (mtCOII) and 112 sequences obtained were of high quality. These sequences were compared with those obtained by our research group from individuals directly sampled in the field, with precise geographic origin. So, a more specific geographic area of the Colombian territory could be considered for a correct rehabilitation treatment during the reintroduction of these confiscated animals. The main results with five primate species were: 1--For all the specimens analyzed of Saguinus leucopus, they could be liberated in any geographical area of its distribution range, since only one gene pool was found. 2--For the 14 Aotus sp. individuals sequenced from the SDA (Environmental District Secretariat), one of them (A. vociferans) was coming from the Amazon, seven exemplars belonged to A. griseimembra from the Magdalena Valley and the Colombian Caribbean coasts, four individuals represented to A. brumbacki from the Colombian Eastern Llanos, and two were associated to A. azarae azarae from Northern Argentina and Paraguay (which means that illegal traffic of animals is arriving to Colombia from other South-American countries). 3--Out 14 Cebus albifrons sequenced, two belonged to the geographical area of C. a. versicolor, one to C. a. pleei, 10 to C a. leucocephalus and one could be not assigned because its sequence yielded a great genetic divergence with respect to the other specimens sequenced of this species. 4--The two Cebus capucinus sequenced showed to be associated to a gene pool found in the Northern of Chocó, Sucre and Córdoba Departments. 5--Out 11 Cebus apella sequenced, 10 showed to belong to the gene pool presented in the Colombian Eastern Llanos and highly related (but differentiable) to Cebus apella apella from the French Guyana. It could be named C. a. fatuellus sensu Groves (2001). One exemplar sequenced could be not related with the other C. apella analyzed, nor the related taxa to the aforementioned species (C. a. paraguayanus = C. cay; C. xanthosternos; C. nigritus).

Among soil microorganisms, Actinomycetes play an important role in the sustainability of natural and agricultural systems: decomposition of organic matter; degradation of recalcitrant compounds like lignin; nitrogen fixation; degradation of agricultural chemicals and biological control in plants and animals. We evaluated their diversity in soils under three different vegetation covers (pasture, tropical primary forest and stubble) at two depths in the Southern Colombian Amazon border. We collected five replicates per vegetation type (in each, three samples at 0-20cm and three at 20-30cm; for a total of 30 samples). Abundance and phenotypic diversity were determined by plate counting. Genomic DNA was extracted from the isolates: the 16s rDNA gene was amplified with specific primers, and its genetic diversity was estimated by means of an amplified restriction analysis (ARDRA). Actynomicetes abundance varied with vegetation and depth, possibly reflecting presence of earthworms, macro-fauna and physico-chemical characteristics associated to fertility, as well as organic matter, total bases, and optimal capacity to cationic interchange. Primary forests had the highest diversity. Sixteen morpho-types (six genera) were identified; Streptomyces was the most abundant everywhere. The heterogeneity ofARDRA patterns prevented species identification because of the intra-species variability in sequences of 16s rDNA operons. This community is a biological indicator of landscape alteration and could include new bio-active compounds of pharmaceutical interest.

Species conservation programs are highly based on analyses of population genetics. We compared eight Neotropical Cervidae (Mazama americana, M. gouzaoubira, M. rufina, Odocoileus virginianus, Hippocamelus antisensis, Pudu mephistopholes, Ozotoceros bezoarticus and Blastoceros dichotomus) and some European and Asian Cervidae (Cervus elaphus, C. nippon, Capreolus capreolus, C. pygargus and Dama dama). The European species C. elaphus was our standard for a high degree of genetic variability: we used a Scottish population originated in the mix of diverse Western European subspecies. On the contrary, Cervus nippon (a population from Scotland with a founder effect) was our standard for a depauperated population. The M. americana, M. gouzaoubira and O. virginianus samples had high diversity values close to our C. elaphus population (H = 0.64, 0.70 and 0.61, respectively), while M. rufina was very low, close to C. nippon. Several sample sets of Mazama and Odocoileus yielded a homozygote excess, probably due to the Wahlund (subdivison) effect. There was no evidence of recent bottleneck events.

Los primates son uno de los grupos de mamíferos más decomisados por la autoridades ambientales (SDA) en Bogotá, Colombia. Un total de 133 primates fueron confiscados en Bogotá durante el año 2008 y mantenidos en las instalaciones de la SDA. De ellos, 115 fueron secuenciados para el gen mitocondrial citocromo oxidasa II (mtCOII) y en 112 ejemplares, las secuencias obtenidas fueron de alta calidad. Esas secuencias se compararon con las obtenidas para ejemplares muestreados directamente en campo por nuestro grupo de investigación y con origen geográfico conocido. De ese modo, se pudo determinar las áreas geográficas, en el territorio colombiano, donde pueden liberarse esos ejemplares después del tratamiento de rehabilitación oportuno. Los resultados principales para las cinco especies de primates fueron como siguen: 1- Para Saguinus leucopus, los animales analizados pueden ser liberados en cualquier área geográfica dentro del rango de distribución de la especie, ya que solo se detectó un acervo genético sin estructura espacial. 2- Para los 14 Aotus sp. secuenciados procedentes de la SDA, se determinó que: uno de ellos pertenecía a A. vociferans, propio de la Amazonía; siete ejemplares pertenecieron a A. griseimembra, propio del valle del Magdalena hasta la costa Caribe colombiana; cuatro ejemplares representaron a A. brumbacki, de los Llanos Orientales de Colombia; y dos ejemplares se asociaron con A. azarae azarae del norte de Argentina y Paraguay, con lo cual se muestra que en Colombia se está recibiendo fauna ilegal procedente de otros países. 3- De los 14 Cebus albifrons secuenciados, dos pertenecieron al área geográfica de distribución de C. a. versicolor; uno al de C. a. pleei, 10 al de C. a. leucocephalus, y uno no pudo ser asignado ya que su secuencia mostraba gran divergencia respecto a los otros ejemplares secuenciados de esta especie. 4- Los dos Cebus capucinus secuenciados mostraron estar asociados a un acervo genético encontrado en el norte del Chocó, Sucre y Córdoba. 5- De 11 Cebus apella secuenciados, 10 mostraron pertenecer al acervo genético que se encuentra en los Llanos Orientales de Colombia y altamente relacionado a Cebus apella apella de la Guyana Francesa, aunque podrían representar un acervo propio de Colombia, C. a. fatuellus sensu Groves (2001). Un individuo no pudo ser relacionado con ningún grupo de los otros C. apella estudiados, ni con los taxones relacionados a la especie mencionada, pero, probablemente, con su propio estatus taxonómico (C. a. paraguayanus = C. cay, C. xanthosternos, C. nigritus).Genetic methods for the reintroduction of primates Saguinus, Aotus and Cebus (Primates: Cebidae) seized in Bogota, Colombia. Primates are one of more confiscated taxa by the environmental authorities in Bogota, Colombia. During 2008, 133 monkeys were confiscated; samples from 115 of them were sequenced by the mitochondrial cythocrome oxidase II gene (mtCOII) and 112 sequences obtained were of high quality. These sequences were compared with those obtained by our research group from individuals directly sampled in the field, with precise geographic origin. So, a more specific geographic area of the Colombian territory could be considered for a correct rehabilitation treatment during the reintroduction of these confiscated animals. The main results with five primate species were: 1- For all the specimens analyzed of Saguinus leucopus, they could be liberated in any geographical area of its distribution range, since only one gene pool was found. 2- For the 14 Aotus sp. individuals sequenced from the SDA (Environmental District Secretariat), one of them (A. vociferans) was coming from the Amazon, seven exemplars belonged to A. griseimembra from the Magdalena Valley and the Colombian Caribbean coasts, four individuals represented to A. brumbacki from the Colombian Eastern Llanos, and two were associated to A. azarae azarae from Northern Argentina and Paraguay (which means that illegal traffic of animals is arriving to Colombia from other South-American countries). 3-Out 14 Cebus albifrons sequenced, two belonged to the geographical area of C. a. versicolor, one to C. a. pleei, 10 to C. a. leucocephalus and one could be not assigned because its sequence yielded a great genetic divergence with respect to the other specimens sequenced of this species. 4- The two Cebus capucinus sequenced showed to be associated to a gene pool found in the Northern of Chocó, Sucre and Córdoba Departments. 5- Out 11 Cebus apella sequenced, 10 showed to belong to the gene pool presented in the Colombian Eastern Llanos and highly related (but differentiable) to Cebus apella apella from the French Guyana. It could be named C. a. fatuellus sensu Groves (2001). One exemplar sequenced could be not related with the other C. apella analyzed, nor the related taxa to the aforementioned species (C. a. paraguayanus =C. cay; C. xanthosternos; C. nigritus). Rev. Biol. Trop. 58 (3): 1049-1067. Epub 2010 September 01.

Sixteen isoenzyme patterns were analyzed for five Colombian Lutzomyia species. The average unbiased expected heterozygosity levels ranged from 0.098 (Lu. youngi) to 0.215 (Lu. torrvida). The five species samples, taken all the isoenzymes employed, were significantly deviated from the Hardy-Weinberg equilibrium by homozygous excess with classical as well as Markov chain exact tests. Possible causes: (1) Wahlund effect within populations due to subdivision and/or sampling. Endogamy could be discarded because these loci were affected by highly different levels of homozygous excess. (2) Null alleles could be not discarded, at least for some isoenzymes. The hierarchical Wright's F analysis showed high and significant values for each parameter. The average F(IT) value was 0.655 with a conspicous homozygous excess at a global level (all species taken together); the average F(IS) value was significantly positive (0.515) as well, with homozygous excess within each species. The genetic heterogeneity between the fives species was noteworthy (F(ST) 0.288), indicating clear genetic differentiation. The more related species pairs were Lu. longiflocosa-Lu. torvida (0.959) and Lu torvida-Lu. spinicrassa (0.960); while Lu. torvida-Lu. youngi (0.805) and Lu. quasitownsendi-Lu. youngi (0.796) were the most divergent (Nei's genetic identity matrix). UPGMA and Wagner algorithms showed that the most divergent species was Lu. youngi, whereas the most related were Lu. longiflocosa-Lu. torvida and Lu torvida-Lu. spinicrassa. A spatial autocorrelation analysis (Moran's I index) revealed a very weak, or inexistent spatial structure, which means that the speciation events between these species were independent from the geographic distances from where they currently live.

The genus Cavia occurs in South America, mainly in grasslands. We collected blood samples from 97 individuals in six field populations and analyzed them with RAPD molecular markers. One wild type (C. anolaimae) was differentiated from the domestic form (C. porcellus), in agreement with other authors who used morphological, osteological and karyotipic results. Genetic diversity was considerable in both species, but higher in C. porcellus. The levels of genetic heterogeneity were also higher among the populations of C. porcellus (F(ST) = 0.254) than among the populations of C. anolaimae (F(ST) = 0.118). These significant levels of genetic heterogeneity, and the low levels of gene flow, were consistent with a complex domestication process for Cavia porcellus.

The current work shows two molecular phylogenetic analyses on Neotropical deers. In the first analysis, the mitochondrial control region (D-loop) was sequenced in six Odocoileinae species from Latin America, using the sequences of two Muntiacinae as outgroups. The results obtained were as follows: A sequence of Mazama americana showed a striking relationship with several sequences of Odocoileus in contrast to that expected, since this M. americana haplotype, from a Mexican origin, was not associated with several Bolivian Mazama sequences analyzed. This could put forward that this genera is not monophyletic. On the other hand, these Bolivian Mazama formed a clade with Pudu puda and Ozotoceros bezoarticus. Likely, an Odocoileus virginianus sequence from the Central area of Colombia showed a more strong relationship with a Northamerican O. heminonus sequence than with the other O. virginianus sequences of Colombian origin as well. This could be explained by means of various different hypotheses. The first is the existence of common ancestral haplotypes between both species. Another one is the reiterative hybridization among both Odocoileus species before the migration of O. virginianus from North America to South America. Moreover, the maximum parsimony analysis showed an intense relationship between the Muntiacinae and this Neotropical Cervidae clade. In addition, and adding credence to the relevant polyphyletism found in Mazama by means of the mitochondrial control region DNA sequences, a second analysis with 16 DNA microsatellite loci also showed a higher genetic relationship between M. americana and O. virginianus, than between the first species regard to Mazama gouazoubira.