Ken Oyama

Universidad Nacional Autónoma de México, Mexico City, The Federal District, Mexico

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Publications (66)151.39 Total impact

  • [Show abstract] [Hide abstract]
    ABSTRACT: Question: Along an altitudinal gradient of 2000 min a semi-tropicalmountain, we explored the relation between tree specific diversity and community functional composition by studying variations in tree allometry, stem and leaf functional traits, and their relationship with temperature and precipitation. Location: Tequila Volcano, Jalisco,Mexico (20°48′ N, 103°51′ W). Methods: We surveyed tree specific diversity, five forest structural parameters and six functional traits in ten horizontal transects (50–75 m in length) located every 200 malong a 2000-mgradient (from800 to 2800 ma.s.l.).We calculated alpha and beta diversity, and quantified the community-weighted means for wood and bark density, Huber value (sapwood to leaf area ratio), leaf area, leaf dry mass content and leaf mass per unit area. The patterns of association were explored using Pearson correlations, and summarized using PCA. Results: Alpha diversity was independent of altitude, and species turnover was almost complete between consecutive transects. Altitude (and its associated abiotic factors, temperature and precipitation) were highly correlated with functional traits. Maximum tree height, total basal area and the communityweighted mean values for leaf mass per unit area, leaf drymass content, and the Huber values were positively correlated with altitude, and the opposite was found for the number of basal stems. Stem and leaf trait values were correlated along the altitudinal gradient. Conclusions: Altitude imposes environmental filters at the community scale that determine a high species replacement. Stem and leaf traits were correlated along the gradient; trees at higher altitudes were tallerwith a single stem, higher density of wood and bark, and leaves with higher leaf mass per area and dry mass content than in the low-altitude sites. These results suggest the consistency of a fast–slow acquisitive trade-off across environments, tending to promote slow acquisition and high longevity at higher altitudes.
    Journal of Vegetation Science 10/2014; · 2.82 Impact Factor
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    ABSTRACT: The role of plant polyphenols as defenses against insect herbivores is controversial. We combined correlative field studies across three geographic regions (Northern Mexico, Southern Mexico, and Costa Rica) with induction experiments under controlled conditions to search for candidate compounds that might play a defensive role in the foliage of the tropical oak, Quercus oleoides. We quantified leaf damage caused by four herbivore guilds (chewers, skeletonizers, leaf miners, and gall forming insects) and analyzed the content of 18 polyphenols (including hydrolyzable tannins, flavan-3-ols, and flavonol glycosides) in the same set of leaves using high performance liquid chromatography and mass spectrometry. Foliar damage ranged from two to eight percent per region, and nearly 90% of all the damage was caused by chewing herbivores. Damage due to chewing herbivores was positively correlated with acutissimin B, catechin, and catechin dimer, and damage by mining herbivores was positively correlated with mongolinin A. By contrast, gall presence was negatively correlated with vescalagin and acutissimin B. By using redundancy analysis, we searched for the combinations of polyphenols that were associated to natural herbivory: the combination of mongolinin A and acutissimin B had the highest association to herbivory. In a common garden experiment with oak saplings, artificial damage increased the content of acutissimin B, mongolinin A, and vescalagin, whereas the content of catechin decreased. Specific polyphenols, either individually or in combination, rather than total polyphenols, were associated with standing leaf damage in this tropical oak. Future studies aimed at understanding the ecological role of polyphenols can use similar correlative studies to identify candidate compounds that could be used individually and in biologically meaningful combinations in tests with herbivores and pathogens.
    Journal of Chemical Ecology 05/2014; · 2.46 Impact Factor
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    ABSTRACT: The repeated use of sleeping sites by frugivorous vertebrates promotes the deposition and aggregation of copious amounts of seeds in these sites. This spatially contagious pattern of seed deposition has key implications for seed dispersal, particularly because such patterns can persist through recruitment. Assessing the seed rain patterns in sleeping sites thus represents a fundamental step in understanding the spatial structure and regeneration of plant assemblages. We evaluated the seed rain produced by spider monkeys (Ateles geoffroyi) in latrines located beneath 60 sleeping trees in two continuous forest sites (CFS) and three forest fragments (FF) in the Lacandona rainforest, Mexico. We tested for differences among latrines, among sites, and between forest conditions in the abundance, diversity (α-, β- and, γ-components) and evenness of seed assemblages. We recorded 45,919 seeds ≥5 mm (in length) from 68 species. The abundance of seeds was 1.7 times higher in FF than in CFS, particularly because of the dominance of a few plant species. As a consequence, community evenness tended to be lower within FF. β-diversity of common and dominant species was two times greater among FF than between CFS. Although mean α-diversity per latrine did not differ among sites, the greater β-diversity among latrines in CFS increased γ-diversity in these sites, particularly when considering common and dominant species. Our results support the hypothesis that fruit scarcity in FF can 'force' spider monkeys to deplete the available fruit patches more intensively than in CFS. This feeding strategy can limit the effectiveness of spider monkeys as seed dispersers in FF, because (i) it can limit the number of seed dispersers visiting such fruit patches; (ii) it increases seed dispersal limitation; and (iii) it can contribute to the floristic homogenization (i.e., reduced β-diversity among latrines) in fragmented landscapes.
    PLoS ONE 01/2014; 9(2):e89346. · 3.53 Impact Factor
  • Revista Mexicana de Ciencias Pecuarias 12/2013; 4(4):417-434. · 0.31 Impact Factor
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    ABSTRACT: The nesting colony of green sea turtles (Chelonia mydas) at Guanahacabibes Peninsula Biosphere Reserve and National Park is one of the largest in the Cuban archipelago; however, little information about its nesting ecology is available. Temporal and spatial variation in nesting and reproductive success as well as morphometric characteristics of gravid females were used to ecologically characterize this colony. Nine beaches of the Southernmost coast of Guanahacabibes Peninsula were monitored for 14 years (1998-2012) to determine green turtle nesting activity, from May to September (peak nesting season in this area). Beach dimensions were measured to determine nest density using the length and the area. Afterward the beaches were divided in two categories, index and secondary. Females were measured and tagged to compare new tagged females (823) with returning tagged females (140). Remigration interval was also determined. Temporal variation was identified as the annual number of nesting emergences and oviposits per female, with apparent peaks in reproductive activity on a biennial cycle in the first six years followed by periods of annual increase in nest number (2003-2008) and periods of decreasing number of nests (2010-2012). We also found intra-seasonal variation with the highest nesting activity in July, particularly in the second half of the month. The peak emergence time was 22:00-02:00 hr. In terms of spatial variation, smaller beaches had the highest nest density and nesting was more frequent 6-9m from the high tide line, where hatchling production was maximized although hatchling success was high on average, above 80%. Morphometric analysis of females was made and newly tagged turtles were smaller on average than remigrants. Our results are only a first attempt at characterizing Guanahacabibes' populations but have great value for establishing conservation priorities within the context of national management plans, and for efficient monitoring and protection of nesting beaches.
    Revista de biologia tropical 12/2013; 61(4):1935-45. · 0.55 Impact Factor
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    ABSTRACT: • Premise of study: Anthropogenic fragmentation is an ongoing process in many forested areas that may create loss of connectivity among tree populations and constitutes a serious threat to ecological and genetic processes. We tested the central hypothesis that seed dispersal mitigates the impact of fragmentation by comparing connectivity and genetic diversity of adult vs. seedling populations in recently fragmented populations of the Mexican red oak Quercus castanea.• Methods: Adult individuals, established before fragmentation, and seedlings, established after fragmentation, were sampled at 33 forest fragments of variable size (0.2 to 294 ha) within the Cuitzeo basin, Michoacán state, and genotyped using seven highly polymorphic chloroplast microsatellite markers (cpSSRs). To test whether seed dispersal retains connectivity among fragmented populations, we compared genetic diversity and connectivity networks between adults and progeny and determined the effect of fragment size on these values.• Key results: Seventy haplotypes were identified, 63 in the adults and 60 in the seedlings, with average within-population diversity (hS) values of 0.624 in the adults and 0.630 in the seedlings. A positive correlation of genetic diversity values with fragment size was found in the seedling populations but not in the adult populations. The network connectivity analysis revealed lower connectivity among seedling populations than among adults. The number of connections (edges) as well as other network properties, such as betweenness centrality, node degree and closeness, were significantly lower in the seedlings network.• Conclusions: Habitat fragmentation in this landscape is disrupting seed-dispersal-mediated genetic connectivity among extant populations.
    American Journal of Botany 08/2013; · 2.59 Impact Factor
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    ABSTRACT: Mexico is the main center of diversity of the genus Quercus in the Western Hemisphere. Despite recent advances in the knowledge of Mexican oaks, a degree of taxonomic confusion still remains, mainly within particular species complexes. In this study, scanning electron microscopy was used to describe micromorphological foliar structures (trichomes, epicuticular waxes and stomata) from the abaxial and adaxial leaf surfaces of Mexican oak species, with the main goal of assessing the taxonomical utility of these characters. In total, 27 species belonging to sections Quercus (white oaks) and Lobatae (red/black oaks) were examined, particularly focusing on several groups of closely related species with problematic taxonomic delimitation and on species that are known to hybridize. Several trichome types were observed, including both glandular (simple and bulbous) and eglandular (solitary, multiradiate, stellate, fused stellate and fasciculate stipitate). Epicuticular waxes were structured as films, grooved films, crusts, granules, platelets and platelets arranged in rosettes. Stomata were elliptical and raised above or leveled with the foliar surface. Among the three types of structures examined, trichomes appeared to be the most useful for taxonomical purposes, followed by epicuticular waxes. All species had different combinations of character states for these micromorphological structures, which permitted the elaboration of keys to identify species within the problematic groups.
    Acta botánica Mexicana 07/2013; · 0.31 Impact Factor
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    ABSTRACT: We present a cost-effective statistical approach that integrates satellite imagery, environmental variables and ground inventory data to map the spatial distribution of aboveground woody biomass suitable for charcoal making. The study was conducted in the Cuitzeo basin located in central Mexico, where charcoal is produced from oak forests covering approximately 10% of the total area (4033 km2). Diameters of trees and sprouts in 78 plots of 0.2 ha each was measured. Allometric equations previously developed locally that only require tree diameters were employed to estimate the amount of woody biomass suitable for charcoal making i.e. the amount of wood that is loaded into the kilns. The performance of two statistical techniques for the interpolation of field data was assessed by cross-validation; these techniques were linear regression and regression-kriging, the second taking into account the spatial autocorrelation of data. Spectral bands, vegetation indices, texture measurements and variables derived from a Digital Elevation Model were examined as explanatory variables. Accounting for spatial autocorrelation (regression-kriging) improved the model's R2 from 0.61 to 0.69, representing a relative error reduction of 11.3% (from 11.01 to 9.77 t ha− 1 of wood suitable for charcoal). The available stock was compared to current estimates of charcoal demand in the Cuitzeo basin and insights were given on how this information can be used to estimate the annual sustainable production potential of oak in order to account for supply–demand balances.
    Energy for Sustainable Development 04/2013; 17(2):177–188. · 2.22 Impact Factor
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    ABSTRACT: Lilaea scilloides (Juncaginaceae) is an aquatic species inhabiting temporary wetlands. It is an annual herbaceous emergent plant distributed from Canada to Argentina. This species reproduces both sexually and asexually, and is wind-pollinated. Flowers are highly heteromorphic with 5 different types of flowers. We hypothesized that, because of its pollination syndrome, wide distribution and local abundance, the species would have high genetic diversity, low endogamy, low genetic differentiation, and high gene flow. The objectives of this study were to determine the genetic diversity and structure of L. scilloides and compare with species with similar ecological and life history traits. We analyzed 40 individuals from 12 populations using isozyme electrophoresis in starch gels. The results showed a low within population genetic diversity (A= 1.77, Ae= 1.15, P= 56.6, Ho= 0.064 and He= 0.103), a high endogamy index (FIS= 0.288), low genetic differentiation among populations (FST= 0.077), and high gene flow (Nm= 4.42). We also found evidence of a high degree of clonal propagation in the species. These results indicate that asexual reproduction is extremely important for the species, as well as the possibility that Lilaea scilloides has hydrophilous pollination, which has not been previously reported.
    REVISTA MEXICANA DE BIODIVERSIDAD 03/2013; 84(1):240-248. · 0.39 Impact Factor
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    ABSTRACT: The evolution of plant defense traits has traditionally been explained trough the “coevolutionary arms race” between plants and herbivores. According to this, specialist herbivores have evolved to cope effectively with the defensive traits of their host plants and may even use them as a cue for host location. We analyzed the geographic association between leaf trichomes, two tropane alkaloids (putative resistance traits), and leaf damage by herbivores in 28 populations of Datura stramonium in central Mexico. Since the specialist leaf beetles Epitrix parvula and Lema trilineata are the main herbivores of D. stramonium in central Mexico, we predicted a positive association between plant defense and leaf damage across populations. Also, if physical environmental conditions (temperature or precipitation) constrain the expression of plant defense, then the geographic variation in leaf damage should be explained partially by the interaction between defensive traits and environmental factors. Furthermore, we studied the temporal and spatial variation in leaf trichome density and leaf damage in five selected populations of D. stramonium sampled in two periods (1997 vs. 2007). We found a positive association between leaf trichomes density and atropine concentration with leaf damage across populations. The interaction between defensive traits and water availability in each locality had a significant effect on the geographic variation in leaf damage. Differences among populations in leaf trichome density are maintained over time. Our results indicate that local plant–herbivore interaction plays an important role in shaping the geographic and temporal variation in plant defense in D. stramonium.
    Ecological Research. 01/2013;
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    ABSTRACT: Abstract: In tropical latitudes, the analysis of leaf phenology in tree species of lineages with temperate origin can help better understanding the potential effects of climate change on these forests. Over three years (2008–2010), we recorded the timing of bud burst (BB), leaf unfolding (LU), and leaf spreading (LS) and their relation to temperature, precipitation, and soil water potential in two deciduous oak species (Quercus magnoliifolia Née and Quercus resinosa Liebm.) along an altitudinal gradient at the Tequila Volcano, central Mexico. Quercus magnoliifolia was monitored at three altitudes, 1450, 1667, and 1787 m, and Q. resinosa was monitored at 1787, 2055, and 2110 m. The onset of BB, LU, and LS occurred earlier at lower elevations with higher temperature in Q. magnoliifolia, but in Q. resinosa only the onset of BB occurred later at lower elevations with higher temperature. BB, LU, and LS were not correlated with rainfall and soil water potential in the two species. The total duration time of leaf development was not significantly correlated with rainfall in Q. magnoliifolia, but a significant negative correlation with rainfall was found in Q. resinosa. Results indicated that leaf phenology of the two examined oak species exhibited contrasting responses to temperature and precipitation.
    Canadian Journal of Forest Research 01/2013; 43:208-213. · 1.56 Impact Factor
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    ABSTRACT: The prevailing view that insects lack endogenous enzymes for plant cell wall (PCW) digestion had led to the hypothesis that PCW digestion evolved independently in different insect taxa through the establishment of symbiotic relationships with microorganisms. However, recent studies reporting endogenous PCW-degrading genes and enzymes for several insects, including phylogenetically basal insects and closely related arthropod groups, challenge this hypothesis. Here, we summarize the molecular and biochemical evidence on the mechanisms of PCW digestion in insects to analyze its evolutionary pathways. The evidence reveals that the symbiotic-independent mechanism may be the ancestral mechanism for PCW digestion. We discuss the implications of this alternative hypothesis in the evolution of plant-insect interactions and suggest that changes in the composition of lignocellulolytic complexes were involved in the evolution of feeding habits and diet specializations in insects, playing important roles in the evolut...
    11/2012; 43:45-71.
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    ABSTRACT: We used mitochondrial DNA (mtDNA) sequence data and allele frequencies at eight microsatellite loci to examine the population genetic structure, estimate the divergence times of distinct lineages, and infer patterns associated with host colonization in populations of the bark beetle Dendroctonus approximatus in Mexico. Two haplotype groups were identified using mtDNA sequences in 71 individuals from 15 populations. The first group was distributed in the Sierra Madre Occidental (SMOc, Western Mexico), with some populations in the Faja Volcánica Transmexicana (Central Mexico), and the second was found in the Sierra Madre Oriental (SMOr, Eastern Mexico), with populations in the Sierra Madre del Sur (Southern Mexico). The estimated split between groups occurred in the late Pleistocene, around 0.195 Mya. Microsatellite allele frequencies revealed high genetic differentiation between pairwise populations, and genetic differentiation values indicated a genetic structure of isolation by distance. Both mtDNA sequence data and microsatellite allele frequencies indicated that D. approximatus had two independent colonization routes in Mexico, one through the SMOc and another along the SMOr. The widespread geographic distribution of D. approximatus in Mexico follows a model of population range expansion of two haplotype groups in which gene flow is restricted by the geographic separation between hosts imposed by physical barriers between populations.
    The Journal of heredity 09/2012; 103(5):638-50. · 2.05 Impact Factor
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    ABSTRACT: Sustainable production systems for woodfuels in developing countries require basic information on tree productivity, and particularly on their coppicing productivity under current forms of management. We report biomass equations and sprouting productivity of two oak species (Quercus castanea and Q. laeta) subject to traditional forms of woodfuel harvesting at Cuitzeo basin in central Mexico. Biomass components analyzed were total aboveground biomass (AGB), woody biomass suitable for charcoal making (WSC) and residues (foliage and small branches). The estimation of total aboveground biomass (AGB) and woody biomass suitable for charcoal making (WSC) of individual trees, when expressed as a function of DBH in the form y=a(DBH)b, resulted in values of pseudo-R2 higher than 92%. The Mean Annual Increment (MAI) of both species increased with site age. Significant differences were found in re-growth rates of these species. Maximum charcoal potential productivity in kgha−1 year−1 is achieved between 30 to 50 years depending on the decay rate of coppicing-shoot density over time. This roughly doubles current harvest cycles of 10-15 years followed by charcoalers. Oaks in developing countries have the potential to be used as a mid-term rotation coppice species for energy purposes. We argue that the results shown in this study are an important input for designing appropriate management strategies for traditional oak-charcoal production in developing countries.
    Biomass & Bioenergy - BIOMASS BIOENERG. 01/2012;
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    ABSTRACT: Spider monkeys (Ateles geoffroyi) use sites composed of one or more trees for sleeping (sleeping sites and sleeping trees, respectively). Beneath these sites/trees they deposit copious amounts of dung in latrines. This behavior results in a clumped deposition pattern of seeds and nutrients that directly impacts the regeneration of tropical forests. Therefore, information on the density and spatial distribution of sleeping sites and latrines, and the characteristics (i.e., composition and structure) of sleeping trees are needed to improve our understanding of the ecological significance of spider monkeys in influencing forest composition. Moreover, since primate populations are increasingly forced to inhabit fragmented landscapes, it is important to assess if these characteristics differ between continuous and fragmented forests. We assessed this novel information from eight independent spider monkey communities in the Lacandona rainforest, Mexico: four continuous forest sites and four forest fragments. Both the density of sleeping sites and latrines did not differ between forest conditions. Latrines were uniformly distributed across sleeping sites, but the spatial distribution of sleeping sites within the areas was highly variable, being particularly clumped in forest fragments. In fact, the average inter-latrine distances were almost double in continuous forest than in fragments. Latrines were located beneath only a few tree species, and these trees were larger in diameter in continuous than fragmented forests. Because latrines may represent hotspots of seedling recruitment, our results have important ecological and conservation implications. The variation in the spatial distribution of sleeping sites across the forest indicates that spider monkeys likely create a complex seed deposition pattern in space and time. However, the use of a very few tree species for sleeping could contribute to the establishment of specific vegetation associations typical of the southeastern Mexican rainforest, such as Terminalia-Dialium, and Brosimum-Dialium.
    PLoS ONE 01/2012; 7(10):e46852. · 3.53 Impact Factor
  • XVIII International Botanical Congress; 07/2011
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    ABSTRACT: c1 Corresponding author. Email: pcuevas@oikos.unam.mx
    Journal of Tropical Ecology 06/2011; 27(04):383 - 391. · 1.48 Impact Factor
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    ABSTRACT: Guaiacum unijugum is a rare shrub endemic to a 70 km stretch of coastline extending east from San José del Cabo in Baja California and is the least well–known of the 4 species of Guaiacum in Mexico. To increase our knowledge of this species and assess its conservation status we surveyed the extent of occurrence using both herbarium material and field work, assessed levels of genetic diversity, determined its phylogenetic relationships, and completed an evaluation of risk of extinction (MER). Herbarium material identified 5 known localities of occurrence with field work verifying the continued persistence of 4 of these with an additional site discovered. Genetic analysis across the small range using 17 microsatellite loci showed very low levels of genetic diversity with a mean expected heterozygosity (HE) of 0.162 over all polymorphic loci. Most loci were found to be monomorphic and genetic divergence was small, maintained by the presence of rare private alleles in widely–separated populations. Phylogenetic analysis indicated a sister group relationship to G. coulteri along the Pacific coast suggesting vicariance for the origin and occurrence of G. unijugum. The unique evolutionary history coupled with current small population sizes warrants increased conservation via listing as a critically endangered species.
    REVISTA MEXICANA DE BIODIVERSIDAD 12/2010; 81(3):745-758. · 0.39 Impact Factor
  • Sofía Solórzano, Ken Oyama
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    ABSTRACT: The resplendent Quetzal (Pharomachrus mocinno) is an endemic Mesoamerican bird species of conservation concern. Within this species, the subspecies P. m. costaricensis and P. m. mocinno, have been recognized by apparent morphometric differences; however, presently there is no sufficient data for confirmation. We analyzed eight morphometric attributes of the body from 41 quetzals: body length, tarsus and cord wing, as well as the length, wide and depth of the bill, body weight; and in the case of the males, the length of the long upper-tail cover feathers. We used multivariate analyses to discriminate morphometric differences between subspecies and contrasted each morphometric attribute between and within subspecies with paired non-parametric Wilcoxon test. In order to review the intraspecific taxonomic status of this bird, we added phylogenetic analysis, and genetic divergence and differentiation based on nucleotide variations in four sequences of mtDNA. The nucleotide variation was estimated in control region, subunit NDH6, and tRNAGlu and tRNAPhe in 26 quetzals from eight localities distributed in five countries. We estimated the genetic divergence and differentiation between subspecies according to a mutation-drift equilibrium model. We obtained the best mutation nucleotide model following the procedure implemented in model test program. We constructed the phylogenetic relationships between subspecies by maximum parsimony and maximum likelihood using PAUP, as well as with Bayesian statistics. The multivariate analyses showed two different morphometric groups, and individuals clustered according to the subspecies that they belong. The paired comparisons between subspecies showed strong differences in most of the attributes analyzed. Along the four mtDNA sequences, we identified 32 nucleotide positions that have a particular nucleotide according to the quetzals subspecies. The genetic divergence and the differentiation was strong and markedly showed two groups within P. mocinno that corresponded to the quetzals subspecies. The model selected for our data was TVM+G. The three phylogenetic methods here used recovered two clear monophyletic clades corresponding to each subspecies, and evidenced a significant and true partition of P. mocinno species into two different genetic, morphometric and ecologic groups. Additionally, according to our calculations, the gene flow between subspecies is interrupted at least from three million years ago. Thus we propose that P. mocinno be divided in two independent species: P. mocinno (Northern species, from Mexico to Nicaragua) and in P. costaricensis (Southern species, Costa Rica and Panama). This new taxonomic classification of the quetzal subspecies allows us to get well conservation achievements because the evaluation about the kind and magnitude of the threats could be more precise.
    Revista de biologia tropical 03/2010; 58(1):357-71. · 0.55 Impact Factor
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    ABSTRACT: Interspecific gene flow can occur in many combinations among species within the genus Quercus, but simultaneous hybridization among more than two species has been rarely analysed. The present study addresses the genetic structure and morphological variation in a triple hybrid zone formed by Q. hypoleucoides, Q. scytophylla and Q. sideroxyla in north-western Mexico. A total of 247 trees from ten reference and 13 presumed intermediate populations were characterized using leaf shape variation and geometric morphometrics, and seven nuclear microsatellites as genetic markers. Discriminant function analysis was performed for leaf shape variation, and estimates of genetic diversity and structure, and individual Bayesian genetic assignments were obtained. Reference populations formed three completely distinct groups according to discriminant function analysis based on the morphological data, and showed low, but significant, genetic differentiation. Populations from the zone of contact contained individuals morphologically intermediate between pairs of species in different combinations, or even among the three species. The Bayesian admixture analysis found that three main genetic clusters best fitted the data, with good correspondence of reference populations of each species to one of the genetic clusters, but various degrees of admixture evidenced in populations from the contact area. The three oak species have formed a complex hybrid zone that is geographically structured as a mosaic, and comprising a wide range of genotypes, including hybrids between different species pairs, backcrosses and probable triple hybrids.
    Annals of Botany 03/2010; 105(3):389-99. · 3.45 Impact Factor

Publication Stats

544 Citations
151.39 Total Impact Points

Institutions

  • 2001–2013
    • Universidad Nacional Autónoma de México
      • • Centre of Ecosystem Research
      • • Institute of Ecology
      Mexico City, The Federal District, Mexico
  • 2010
    • Fort Lewis College
      • Biology
      Durango, CO, United States
  • 2009
    • National University of Cordoba, Argentina
      Córdoba, Córdoba, Argentina
  • 2007
    • Universidad Michoacana de San Nicolás de Hidalgo
      • Facultad de Biología
      Morelia, Michoacan, Mexico