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1.
Ecol Evol ; 14(7): e11661, 2024 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-38994212

RESUMEN

Environmental gradients have the potential to influence genetic differentiation among populations ultimately leading to allopatric speciation. However, environmental gradients can also facilitate hybridization between closely related taxa. We investigated a putative hybrid zone in western Ecuador, involving two polytypic wren species (Aves: Troglodytidae), Campylorhynchus zonatus and C. fasciatus. Our study addressed two primary questions: (1) Is there evidence of population structure and genetic admixture between these taxa in western Ecuador? and (2) What are the relative contributions of isolation by distance and isolation by the environment to the observed genetic differentiation along the environmental gradient in this region? We analyzed 4409 single-nucleotide polymorphisms (SNPs) from 112 blood samples sequenced using ddRadSeq and a de novo assembly. The optimum number of genetic clusters ranged from 2 to 4, aligning with geographic origins, known phylogenetics, and physical or ecological constraints. We observed notable transitions in admixture proportions along the environmental gradient in western Ecuador between C. z. brevirostris and the northern and southern genetic clusters of C. f. pallescens. Genetic differentiation between the two C. f. pallescens populations could be attributed to an unreported potential physical barrier in central western Ecuador, where the proximity of the Andes to the coastline restricts lowland habitats, limiting dispersal and gene flow, especially among dry-habitat specialists. The observed admixture in C. f. pallescens suggests that this subspecies may be a hybrid between C. z. brevirostris and C. fasciatus, with varying degrees of admixture in western Ecuador and northwestern Peru. We found evidence of isolation by distance, while isolation by the environment was less pronounced but still significant for annual mean precipitation and precipitation seasonality. This study enhances our understanding of avian population genomics in tropical regions.

2.
Genetica ; 150(6): 327-341, 2022 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-36271978

RESUMEN

The coastal waters of Cuba are home to a small, endangered population of West Indian manatee, which would benefit from a comprehensive characterization of the population's genetic variation. We conducted the first genetic assessment of Cuban manatees to determine the extent of the population's genetic structure and characterize the neutral genetic diversity among regions within the archipelago. We genotyped 49 manatees at 18 microsatellite loci, a subset of 27 samples on 1703 single nucleotide polymorphisms (SNPs), and sequenced 59 manatees at the mitochondrial control region. The Cuba manatee population had low nuclear (microsatellites HE = 0.44, and SNP HE = 0.29) and mitochondrial genetic diversity (h = 0.068 and π = 0.00025), and displayed moderate departures from random mating (microsatellite FIS = 0.12, SNP FIS = 0.10). Our results suggest that the western portion of the archipelago undergoes periodic exchange of alleles based on the evidence of shared ancestry and low but significant differentiation. The southeast Guantanamo Bay region and the western portion of the archipelago were more differentiated than southwest and northwest manatees. The genetic distinctiveness observed in the southeast supports its recognition as a demographically independent unit for natural resource management regardless of whether it is due to historical isolation or isolation by distance. Estimates of the regional effective population sizes, with the microsatellite and SNP datasets, were small (all Ne < 60). Subsequent analyses using additional samples could better examine how the observed structure is masking simple isolation by distance patterns or whether ecological or biogeographic forces shape genetic patterns.


Asunto(s)
Trichechus manatus , Animales , Trichechus manatus/genética , Cuba , Repeticiones de Microsatélite , Trichechus/genética , Variación Genética , Genética de Población
3.
Mar Biotechnol (NY) ; 24(2): 276-292, 2022 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-35357634

RESUMEN

The northern quahog (Mercenaria mercenaria) supports lucrative aquaculture industries in the USA. In the southeastern USA, aquacultured M. mercenaria faces increasing risks of summer die-offs from prolonged heat waves. We used a comparative transcriptomic approach to investigate the molecular responses of M. mercenaria and its southern congener, Mercenaria campechiensis, to controlled incremental heat stress over a 4-week period. Mercenaria were exposed to temperatures from 24 to 34 °C with 2.5 °C/week, after which, gill transcriptomes were de novo assembled and annotated. During the 4 weeks of chronic heat exposure, both species had the same survival rate (96%); M. mercenaria experienced body weight gain/loss depending on the originated hatcheries while M. campechiensis experienced an average net weight loss. The upregulated genes in both species included those in chaperone-mediated protein folding and regulation of cell death pathways, while the downregulated genes in both species involved in mRNA processing and splicing pathways. Compared to M. mercenaria, M. campechiensis appears to be more sensitive to prolonged heat stress as indicated by upregulating significantly more genes in coping with oxidative stress and in the protein degradation pathways, while downregulating some inhibitors of apoptosis. We discussed this finding within their ecological and evolutionary context. Our findings highlighted the potential vulnerability of the two quahogs, especially the southern quahog, to continued ocean warming.


Asunto(s)
Mercenaria , Animales , Acuicultura , Branquias , Respuesta al Choque Térmico/genética , Mercenaria/genética , Transcriptoma
4.
Mar Genomics ; 58: 100842, 2021 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-34217485

RESUMEN

The genus Procambarus represents a diverse genus of freshwater crayfish that includes epigean species, stygobitic species, and at least one parthenogenic species. Despite its evolutionary, ecological, and economic importance, most genomic and transcriptomic resources for this genus are limited to a couple of model species. We sequenced the transcriptome of a non-model species, P. erythrops, a geographically restricted stygobitic species from Florida. RNA isolated from gill, muscle and eye tissue was pooled to create a de novo transcriptome assembly using Single Molecule Real-Time sequencing (PacBio), resulting in 19,442 full-length isoforms. The assembly has been deposited in the NCBI (BioProject PRJNA657230). These data will make an important contribution to the comparative study of transcriptome evolution in crayfish and crustaceans.


Asunto(s)
Astacoidea/genética , Transcriptoma , Animales , Florida , Análisis de Secuencia de ARN
5.
Ecohealth ; 17(4): 498-511, 2020 12.
Artículo en Inglés | MEDLINE | ID: mdl-33447876

RESUMEN

We investigated the landscape epidemiology of a globally distributed mammal, the wild pig (Sus scrofa), in Florida (U.S.), where it is considered an invasive species and reservoir to pathogens that impact the health of people, domestic animals, and wildlife. Specifically, we tested the hypothesis that two commonly cited factors in disease transmission, connectivity among populations and abundant resources, would increase the likelihood of exposure to both pseudorabies virus (PrV) and Brucella spp. (bacterial agent of brucellosis) in wild pigs across the Kissimmee Valley of Florida. Using DNA from 348 wild pigs and sera from 320 individuals at 24 sites, we employed population genetic techniques to infer individual dispersal, and an Akaike information criterion framework to compare candidate logistic regression models that incorporated both dispersal and land cover composition. Our findings suggested that recent dispersal conferred higher odds of exposure to PrV, but not Brucella spp., among wild pigs throughout the Kissimmee Valley region. Odds of exposure also increased in association with agriculture and open canopy pine, prairie, and scrub habitats, likely because of highly localized resources within those land cover types. Because the effect of open canopy on PrV exposure reversed when agricultural cover was available, we suggest that small-scale resource distribution may be more important than overall resource abundance. Our results underscore the importance of studying and managing disease dynamics through multiple processes and spatial scales, particularly for non-native pathogens that threaten wildlife conservation, economy, and public health.


Asunto(s)
Brucella , Herpesvirus Suido 1 , Seudorrabia , Enfermedades de los Porcinos , Animales , Animales Domésticos , Animales Salvajes , Seudorrabia/epidemiología , Sus scrofa , Porcinos , Enfermedades de los Porcinos/epidemiología
6.
J Hered ; 111(2): 204-215, 2020 04 02.
Artículo en Inglés | MEDLINE | ID: mdl-31746328

RESUMEN

For species with geographically restricted distributions, the impacts of habitat loss and fragmentation on long-term persistence may be particularly pronounced. We examined the genetic structure of Panama City crayfish (PCC), Procambarus econfinae, whose historical distribution is limited to an area approximately 145 km2, largely within the limits of Panama City and eastern Bay County, FL. Currently, PCC occupy approximately 28% of its historical range, with suitable habitat composed of fragmented patches in the highly urbanized western portion of the range and managed plantations in the more contiguous eastern portion of the range. We used 1640 anonymous single-nucleotide polymorphisms to evaluate the effects of anthropogenic habitat modification on the genetic diversity and population structure of 161 PCC sampled from across its known distribution. First, we examined urban habitat patches in the west compared with less-developed habitat patches in the east. Second, we used approximate Bayesian computation to model inferences on the demographic history of eastern and western populations. We found anthropogenic habitat modifications explain the genetic structure of PCC range-wide. Clustering analyses revealed significant genetic structure between and within eastern and western regions. Estimates of divergence between east and west were consistent with urban growth in the mid-20th century. PCC have low genetic diversity and high levels of inbreeding and relatedness, indicating populations are small and isolated. Our results suggest that PCC have been strongly affected by habitat loss and fragmentation and management strategies, including legal protection, translocations, or reintroductions, may be necessary to ensure long-term persistence.


Asunto(s)
Astacoidea/genética , Ecosistema , Genética de Población , Urbanización , Animales , Teorema de Bayes , Conservación de los Recursos Naturales , Florida , Genotipo , Endogamia , Polimorfismo de Nucleótido Simple , Dinámica Poblacional
7.
Mol Ecol ; 28(11): 2746-2756, 2019 06.
Artículo en Inglés | MEDLINE | ID: mdl-31013375

RESUMEN

Connectivity is central to ecology and evolution as it focuses on the movement of individuals or genes across landscapes. Genetic connectivity approaches aim to understand gene flow but often estimate it indirectly based on metrics of genetic differentiation, which can also be affected by other evolutionary forces such as genetic drift. Gene flow and genetic drift are driven by separate ecological mechanisms with potentially differing effects on genetic differentiation and interpretations of genetic connectivity. The ecological mechanisms contributing to gene flow and genetic drift are primarily effective dispersal, or movement followed by successful reproduction, and the number of breeders in a local population, Nb , respectively. Yet, rarely are these ecological mechanisms and genetic connectivity measured simultaneously across landscapes. We examine the roles of effective dispersal and Nb on genetic connectivity across the entire range of the endangered snail kite (Rostrhamus sociabilis plumbeus), between 2006-2015. We find that both Nb and effective dispersal are important predictors of genetic connectivity across this landscape, but that Nb has a 3 × stronger effect on genetic connectivity. Furthermore, Nb is positively correlated with heterozygosity and allelic richness within patches, suggesting a potentially important role of genetic drift, in addition to gene flow, on genetic connectivity. These results emphasize that conservation efforts should focus on not only between-patch processes of movement but also within-patch processes regarding habitat quality and local population size for increasing genetic connectivity.


Asunto(s)
Aves/genética , Cruzamiento , Especies en Peligro de Extinción , Alelos , Animales , Florida , Variación Genética , Geografía , Modelos Genéticos
8.
Sci Rep ; 8(1): 15892, 2018 10 26.
Artículo en Inglés | MEDLINE | ID: mdl-30367102

RESUMEN

Objectively delimiting species boundaries remains an important challenge in systematics and becomes urgent when unresolved taxonomy complicates conservation and recovery efforts. We examined species boundaries in the imperiled freshwater mussel genus Cyclonaias (Bivalvia: Unionidae) using morphometrics, molecular phylogenetics, and multispecies coalescent models to help guide pending conservation assessments and legislative decisions. Congruence across multiple lines of evidence indicated that current taxonomy overestimates diversity in the C. pustulosa species complex. The only genetically and morphologically diagnosable species in the C. pustulosa species complex were C. pustulosa and C. succissa and we consider C. aurea, C. houstonensis, C. mortoni, and C. refulgens to be synonyms of C. pustulosa. In contrast, all three species in the C. nodulata complex (C. necki, C. nodulata, and C. petrina) were genetically, geographically, and morphologically diagnosable. Our findings have important conservation and management implications, as three nominal species (C. aurea, C. houstonensis, and C. petrina) are being considered for protection under the Endangered Species Act.


Asunto(s)
Bivalvos/clasificación , Animales , Bivalvos/anatomía & histología , Bivalvos/genética , ADN Mitocondrial/clasificación , ADN Mitocondrial/genética , Especies en Peligro de Extinción , Agua Dulce , Filogenia , Estados Unidos
9.
Proc Natl Acad Sci U S A ; 115(34): 8591-8596, 2018 08 21.
Artículo en Inglés | MEDLINE | ID: mdl-30082379

RESUMEN

Movement is important for ecological and evolutionary theory as well as connectivity conservation, which is increasingly critical for species responding to environmental change. Key ecological and evolutionary outcomes of movement, such as population growth and gene flow, require effective dispersal: movement that is followed by successful reproduction. However, the relative roles of movement and postmovement reproduction for effective dispersal and connectivity remain unclear. Here we isolate the contributions of movement and immigrant reproduction to effective dispersal and connectivity across the entire breeding range of an endangered raptor, the snail kite (Rostrhamus sociabilis plumbeus). To do so, we unite mark-resight data on movement and reproduction across 9 years and 27 breeding patches with an integrated model that decomposes effective dispersal into its hierarchical levels of movement, postmovement breeding attempt, and postmovement reproductive success. We found that immigrant reproduction limits effective dispersal more than movement for this endangered species, demonstrating that even highly mobile species may have limited effective connectivity due to reduced immigrant reproduction. We found different environmental limitations for the reproductive component of effective dispersal compared with movement, indicating that different conservation strategies may be needed when promoting effective dispersal rather than movement alone. We also demonstrate that considering immigrant reproduction, rather than movement alone, alters which patches are the most essential for connectivity, thereby changing conservation priorities. These results challenge the assumption that understanding movement alone is sufficient to infer connectivity and highlight that connectivity conservation may require not only fostering movement but also successful reproduction of immigrants.


Asunto(s)
Migración Animal/fisiología , Especies en Peligro de Extinción , Falconiformes/fisiología , Modelos Biológicos , Reproducción/fisiología , Animales , Femenino , Masculino
10.
Genetica ; 146(4-5): 393-402, 2018 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-30046930

RESUMEN

The greater amberjack (Seriola dumerili) is a commercially and recreationally important marine fish species in the southeastern United States, where it has been historically managed as two non-mixing stocks (Gulf of Mexico and Atlantic). Mark-recapture studies and analysis of mitochondrial DNA have suggested the two stocks are demographically independent; however, little is currently known about when and where spawning occurs in Gulf of Mexico amberjack, and whether stock mixture occurs on breeding grounds. The primary objective of this study was to quantify stock mixture among breeding populations of amberjack collected from the Atlantic and Gulf of Mexico. Genetic data based on 11 loci identified very low, though statistically significant differentiation among Gulf of Mexico samples (GST = 0.007, [Formula: see text] = 0.009; all P = 0.001) and between reproductive adults collected from two spawning areas (GST = 0.007, [Formula: see text] = 0.014; all P = 0.001). Naïve Bayesian mixture analysis supported a single genetic cluster [p(S|data) = 0.734] whereas trained clustering (using Atlantic and Gulf spawning fish) gave the highest support to a two-cluster model (p(S|data) = 1.0). Our results support the argument that the genetic structuring of greater amberjack is more complex than the previously assumed two, non-mixing stock model. Although our data provide evidence of limited population structure, we argue in favour of non-panmixia among reproductive fish collected from the Gulf of Mexico and Florida Keys.


Asunto(s)
Demografía/métodos , Perciformes/genética , Reproducción/genética , Grupos de Población Animal/genética , Animales , Océano Atlántico , Teorema de Bayes , Cruzamiento , Análisis por Conglomerados , ADN Mitocondrial/genética , Variación Genética/genética , Genética de Población/métodos , Golfo de México , Repeticiones de Microsatélite/genética , Filogeografía/métodos , Sitios de Carácter Cuantitativo/genética
11.
Mol Ecol ; 26(22): 6463-6477, 2017 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-29024142

RESUMEN

The mid-Holocene has had profound demographic impacts on wildlife on the African continent, although there is little known about the impacts on species from Central Africa. Understanding the impacts of climate change on codistributed species can enhance our understanding of ecosystem dynamics and for formulating restoration objectives. We took a multigenome comparative approach to examine the phylogeographic structure of two poorly known Central African crocodile species-Mecistops sp. aff. cataphractus and Osteolaemus tetraspis. In addition, we conducted coalescent-based demographic reconstructions to test the hypothesis that population decline was driven by climate change since the Last Glacial Maximum, vs. more recent anthropogenic pressures. Using a hierarchical Bayesian model to reconstruct demographic history, we show that both species had dramatic declines (>97%) in effective population size in the 'period following the Last Glacial Maximum 1,500-18,000 YBP. Identification of genetic structuring showed both species have similar regional structure corresponding to major geological features (i.e., hydrologic basin) and that small observed differences between them are best explained by the differences in their ecology and the likely impact that climate change had on their habitat needs. Our results support our hypothesis that climatic effects, presumably on forest and wetland habitat, had a congruent negative impact on both species.


Asunto(s)
Caimanes y Cocodrilos/clasificación , Cambio Climático , Ecosistema , África Central , Caimanes y Cocodrilos/genética , Animales , Teorema de Bayes , Evolución Biológica , Núcleo Celular/genética , ADN Mitocondrial/genética , Genética de Población , Genotipo , Repeticiones de Microsatélite , Filogeografía , Densidad de Población , Dinámica Poblacional , Simpatría
12.
J Hered ; 108(6): 686-692, 2017 Sep 01.
Artículo en Inglés | MEDLINE | ID: mdl-28821182

RESUMEN

Understanding mutation rates can greatly extend the utility of population and conservation genetic analyses. Herein, we present an estimate of genome-wide microsatellite mutation rate in Atlantic sturgeon (Acipenser oxyrinchus) based on parent-offspring transmission patterns. We screened 307 individuals for parentage and mutation-rate analysis applying 43 variable markers. Out of 13228 allele transfers, 11 mutations were detected, producing a mutation rate of 8.3 × 10-4 per locus per generation (95% confidence interval: 1.48 × 10-3, 4.15 × 10-4). Single-step mutations predominated and there were trends toward mutations in loci with greater polymorphism and allele length. Two of the detected mutations were most probably cluster mutations, being identified in 12 and 28 sibs, respectively. Finally, we observed evidences of polyploidy based on the sporadic presence of 3 or 4 alleles per locus in the genotyped individuals, supporting previous reports of incomplete diploidization in Atlantic sturgeon.


Asunto(s)
Peces/genética , Genética de Población , Repeticiones de Microsatélite , Tasa de Mutación , Alelos , Animales , Femenino , Masculino , Poliploidía , Análisis de Secuencia de ADN
13.
J Anim Ecol ; 86(4): 857-865, 2017 07.
Artículo en Inglés | MEDLINE | ID: mdl-28378359

RESUMEN

The decision to disperse or remain philopatric between breeding seasons has important implications for both ecology and evolution, including the potential for carry-over effects, where an individual's previous history affects its current performance. Carry-over effects are increasingly documented although underlying mechanisms remain unclear. Here we test for potential carry-over effects and their mechanisms by uniting hypotheses for the causes and consequences of habitat selection and dispersal across space and time. We linked hypotheses regarding different types of factors and information (environmental conditions, personal and public information) predicted to impact reproductive success and dispersal for an endangered, wetland-dependent bird, the snail kite (Rostrhamus sociabilis plumbeus). To do so, we coupled structural equation modelling with 20 years of mark-recapture and nesting data across the breeding range of this species to isolate potential direct and indirect effects of these factors. We found that water depth at nest sites explained subsequent emigration rates via an indirect path through the use of personal, not public, information. Importantly, we found that these dispersers tended to initiate nests later the following breeding season. This pattern explained a phenological mismatch of nesting with hydrological conditions, whereby immigrants tended to nest later, late nesters tended to experience lower water depths, higher nest failure occurred at lower water depths and higher nest failure explained subsequent breeding dispersal. These results identified a novel potential mechanism for carry-over effects: a phenological mismatch with environmental conditions (water depth) that occurred potentially due to time costs of dispersal. Our results also highlighted a substantial benefit of philopatry - earlier initiation of reproduction - which allows philopatric individuals to better coincide with environmental conditions that are beneficial for successful reproduction. These results have implications for our mechanistic understanding and prediction of carryover effects, and emphasize that local conservation strategies, such as water management, can explain future demography at distant sites connected through dispersal.


Asunto(s)
Distribución Animal , Aves , Especies en Peligro de Extinción , Humedales , Animales , Demografía , Ecosistema , Reproducción
14.
Proc Biol Sci ; 282(1814)2015 Sep 07.
Artículo en Inglés | MEDLINE | ID: mdl-26336178

RESUMEN

Understanding dispersal and habitat selection behaviours is central to many problems in ecology, evolution and conservation. One factor often hypothesized to influence habitat selection by dispersers is the natal environment experienced by juveniles. Nonetheless, evidence for the effect of natal environment on dispersing, wild vertebrates remains limited. Using 18 years of nesting and mark-resight data across an entire North American geographical range of an endangered bird, the snail kite (Rostrhamus sociabilis), we tested for natal effects on breeding-site selection by dispersers and its consequences for reproductive success and population structure. Dispersing snail kites were more likely to nest in wetlands of the same habitat type (lacustrine or palustrine) as their natal wetland, independent of dispersal distance, but this preference declined with age and if individuals were born during droughts. Importantly, dispersing kites that bred in natal-like habitats had lower nest success and productivity than kites that did not. These behaviours help explain recently described population connectivity and spatial structure across their geographical range and reveal that assortative breeding is occurring, where birds are more likely to breed with individuals born in the same wetland type as their natal habitat. Natal environments can thus have long-term and large-scale effects on populations in nature, even in highly mobile animals.


Asunto(s)
Aclimatación/fisiología , Distribución Animal , Ecosistema , Falconiformes/fisiología , Comportamiento de Nidificación , Factores de Edad , Animales , Florida , Geografía , Reproducción/fisiología , Humedales
15.
Proc Biol Sci ; 281(1776): 20132483, 2014 Feb 07.
Artículo en Inglés | MEDLINE | ID: mdl-24335982

RESUMEN

Accurate species delimitation is a central assumption of biology that, in groups such as the Crocodylia, is often hindered by highly conserved morphology and frequent introgression. In Africa, crocodilian systematics has been hampered by complex regional biogeography and confounded taxonomic history. We used rigorous molecular and morphological species delimitation methods to test the hypothesis that the slender-snouted crocodile (Mecistops cataphractus) is composed of multiple species corresponding to the Congolian and Guinean biogeographic zones. Speciation probability was assessed by using 11 mitochondrial and nuclear genes, and cranial morphology for over 100 specimens, representing the full geographical extent of the species distribution. Molecular Bayesian and phylogenetic species delimitation showed unanimous support for two Mecistops species isolated to the Upper Guinean and Congo (including Lower Guinean) biomes that were supported by 13 cranial characters capable of unambiguously diagnosing each species. Fossil-calibrated phylogenetic reconstruction estimated that the species split ± 6.5-7.5 Ma, which is congruent with intraspecies divergence within the sympatric crocodile genus Osteolaemus and the formation of the Cameroon Volcanic Line. Our results underscore the necessity of comprehensive phylogeographic analyses within currently recognized taxa to detect cryptic species within the Crocodylia. We recommend that the community of crocodilian researchers reconsider the conceptualization of crocodilian species especially in the light of the conservation ramifications for this economically and ecologically important group.


Asunto(s)
Caimanes y Cocodrilos/anatomía & histología , Caimanes y Cocodrilos/genética , Distribución Animal , Clasificación/métodos , Conservación de los Recursos Naturales/métodos , Fósiles , Filogenia , África Central , África Occidental , Caimanes y Cocodrilos/fisiología , Animales , Secuencia de Bases , Teorema de Bayes , Núcleo Celular/genética , ADN Mitocondrial/genética , Modelos Genéticos , Datos de Secuencia Molecular , Reacción en Cadena de la Polimerasa Multiplex , Filogeografía/métodos , Análisis de Secuencia de ADN , Cráneo/anatomía & histología , Especificidad de la Especie
16.
Nat Commun ; 4: 2572, 2013.
Artículo en Inglés | MEDLINE | ID: mdl-24096937

RESUMEN

For nearly a century, biologists have emphasized the profound importance of spatial scale for ecology, evolution and conservation. Nonetheless, objectively identifying critical scales has proven incredibly challenging. Here we extend new techniques from physics and social sciences that estimate modularity on networks to identify critical scales for movement and gene flow in animals. Using four species that vary widely in dispersal ability and include both mark-recapture and population genetic data, we identify significant modularity in three species, two of which cannot be explained by geographic distance alone. Importantly, the inclusion of modularity in connectivity and population viability assessments alters conclusions regarding patch importance to connectivity and suggests higher metapopulation viability than when ignoring this hidden spatial scale. We argue that network modularity reveals critical meso-scales that are probably common in populations, providing a powerful means of identifying fundamental scales for biology and for conservation strategies aimed at recovering imperilled species.


Asunto(s)
Escarabajos/fisiología , Ecosistema , Falconiformes/fisiología , Modelos Genéticos , Rana catesbeiana/fisiología , Ursidae/fisiología , Distribución Animal , Animales , Evolución Biológica , Conservación de los Recursos Naturales , Flujo Génico , Dinámica Poblacional
17.
Zookeys ; (298): 77-106, 2013.
Artículo en Inglés | MEDLINE | ID: mdl-23794885

RESUMEN

A new species of palm-pitviper of the genus Bothriechis is described from Refugio de Vida Silvestre Texíguat in northern Honduras. The new species differs from congeners by having 19 dorsal scale rows at midbody, a bright green dorsal coloration in adults, the prelacunal scale fused to the second supralabial, and in representing a northern lineage that is sister to Bothriechis lateralis, which is distributed in Costa Rica and western Panama and is isolated from the new taxon by the Nicaraguan Depression. This represents the 15th endemic species occurring in Refugio de Vida Silvestre Texíguat, one of the richest herpetofaunal sites in Honduras, itself being the country with the highest degree of herpetofaunal endemism in Central America. We name this new species in honor of a Honduran conservationist slain in fighting against illegal logging, highlighting the sacrifices of rural activists in battling these issues and the critical importance of conservation in these areas.


ResumenUna nueva especie de tamagás verde del género Bothriechis se describe del Refugio de Vida Silvestre Texíguat en el norte de Honduras. La nueva especie difiere de sus congéneres por tener filas de 19 escamas dorsales en la mitad del cuerpo, una brillante coloración verde en la porción dorsal del cuerpo en adultos, la escama prelacunal fusionada con la segunda supralabial, y en representación del linaje del norte que es clado hermano de Bothriechis lateralis, la cual se distribuye en Costa Rica y el Occidente de Panamá y está aislada del nuevo taxón por la Depresión de Nicaragua. Representa la decimoquinta especie endémica encontrada en el Refugio de Vida Silvestre Texíguat, uno de los lugares más ricos de herpetofauna en Honduras, el país con el más alto grado de endemismo de la herpetofauna en Centroamérica. Nombramos esta nueva especie en honor a un conservacionista Hondureño asesinado en contienda contra la tala ilegal, destacando los sacrificios de los activistas rurales luchando frente a estos problemas y la importancia crítica de la conservación en estas áreas.

18.
Zootaxa ; 3666: 358-68, 2013.
Artículo en Inglés | MEDLINE | ID: mdl-26217856

RESUMEN

The highlands of northeastern Honduras remain under-characterized in terms of biological diversity, as exemplified by the regularity of new amphibian and reptile taxa discoveries. Following the recent description of a new species of Nototriton from the Sierra de Agalta in northeastern Honduras, we report the discovery of a second new species of Nototriton from the nearby Parque Nacional Montaña de Botaderos. This new taxon, Nototriton mime sp. nov., is distinguished from other Nototriton by its distinctive pale brown dorsal coloration in adult males, relatively large nares, a relatively broad head, mitochondrial sequence divergence, and phylogenetic relationships, and is geographically isolated from other populations of Nototriton.


Asunto(s)
Urodelos/clasificación , Distribución Animal , Estructuras Animales/anatomía & histología , Estructuras Animales/crecimiento & desarrollo , Animales , Tamaño Corporal , Femenino , Honduras , Masculino , Datos de Secuencia Molecular , Tamaño de los Órganos , Filogenia , Urodelos/anatomía & histología , Urodelos/genética , Urodelos/crecimiento & desarrollo
19.
Mol Ecol ; 20(20): 4199-215, 2011 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-21906195

RESUMEN

The Nile crocodile (Crocodylus niloticus) is an ancient icon of both cultural and scientific interest. The species is emblematic of the great civilizations of the Nile River valley and serves as a model for international wildlife conservation. Despite its familiarity, a centuries-long dispute over the taxonomic status of the Nile crocodile remains unresolved. This dispute not only confounds our understanding of the origins and biogeography of the 'true crocodiles' of the crown genus Crocodylus, but also complicates conservation and management of this commercially valuable species. We have taken a total evidence approach involving phylogenetic analysis of mitochondrial and nuclear markers, as well as karyotype analysis of chromosome number and structure, to assess the monophyletic status of the Nile crocodile. Samples were collected from throughout Africa, covering all major bioregions. We also utilized specimens from museum collections, including mummified crocodiles from the ancient Egyptian temples at Thebes and the Grottes de Samoun, to reconstruct the genetic profiles of extirpated populations. Our analyses reveal a cryptic evolutionary lineage within the Nile crocodile that elucidates the biogeographic history of the genus and clarifies long-standing arguments over the species' taxonomic identity and conservation status. An examination of crocodile mummy haplotypes indicates that the cryptic lineage corresponds to an earlier description of C. suchus and suggests that both African Crocodylus lineages historically inhabited the Nile River. Recent survey efforts indicate that C. suchus is declining or extirpated throughout much of its distribution. Without proper recognition of this cryptic species, current sustainable use-based management policies for the Nile crocodile may do more harm than good.


Asunto(s)
Caimanes y Cocodrilos/genética , ADN/genética , Evolución Molecular , Especiación Genética , África , Animales , Antiguo Egipto , Haplotipos , Historia Antigua , Humanos , Momias/historia , Filogeografía , Alineación de Secuencia
20.
Mol Ecol Resour ; 11(4): 757-8, 2011 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-21627775

RESUMEN

This article documents the addition of 111 microsatellite marker loci to the Molecular Ecology Resources Database. Loci were developed for the following species: Acipenser oxyrinchus desotoi, Anopheles nuneztovari sensu lato, Asellus aquaticus, Calopteryx splendens, Calopteryx virgo, Centaurea aspera, Centaurea seridis, Chilina dombeyana, Proctoeces cf. lintoni and Pyrenophora teres f. teres.


Asunto(s)
Bases de Datos Genéticas , Repeticiones de Microsatélite , Acanthaceae/genética , Animales , Artrópodos/genética , Ascomicetos/genética , Cordados/genética , Datos de Secuencia Molecular , Plantas/genética , Análisis de Secuencia de ADN , Trematodos/genética
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