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1.
Parasitol Res ; 121(2): 769-773, 2022 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-35048210

RESUMEN

Hummingbirds (Trochilidae) are sensitive to environmental changes because of their extraordinary ecology, metabolism, and the highest red blood cell counts found in any vertebrate. These physiological attributes may render hummingbirds particularly susceptible to the effects of haemosporidian (blood parasite) infections. Much of the research on haemosporidians in hummingbirds has been conducted in South America; less is known about haemosporidian diversity and prevalence in North America. We sought to determine the prevalence and diversity of haemosporidians in a high-elevation species, the Broad-tailed Hummingbird (Selasphorus platycercus). Blood samples (N = 314) from 25 sites in Colorado and Wyoming were screened for haemosporidians using microscopy (n = 311) and PCR (n = 301). Both microscopy and sequencing diagnostic techniques detected haemosporidians in the same 5 hummingbirds, with an overall prevalence of 1.59%. Positive samples were sequenced at the cytochrome b gene and identified Haemoproteus archilochus and two Haemoproteus sp. not previously detected in North America. No parasites of the genera Plasmodium or Leucocytozoon were detected. Our study provides the first report of the prevalence and diversity of haemosporidians in Broad-tailed Hummingbirds in the Rocky Mountains.


Asunto(s)
Enfermedades de las Aves , Haemosporida , Plasmodium , Infecciones Protozoarias en Animales , Animales , Enfermedades de las Aves/epidemiología , Aves , Haemosporida/genética , Filogenia , Prevalencia , Infecciones Protozoarias en Animales/epidemiología
2.
Mol Ecol ; 28(22): 4926-4940, 2019 11.
Artículo en Inglés | MEDLINE | ID: mdl-31587398

RESUMEN

Apex predators are important indicators of intact natural ecosystems. They are also sensitive to urbanization because they require broad home ranges and extensive contiguous habitat to support their prey base. Pumas (Puma concolor) can persist near human developed areas, but urbanization may be detrimental to their movement ecology, population structure, and genetic diversity. To investigate potential effects of urbanization in population connectivity of pumas, we performed a landscape genomics study of 130 pumas on the rural Western Slope and more urbanized Front Range of Colorado, USA. Over 12,000 single nucleotide polymorphisms (SNPs) were genotyped using double-digest, restriction site-associated DNA sequencing (ddRADseq). We investigated patterns of gene flow and genetic diversity, and tested for correlations between key landscape variables and genetic distance to assess the effects of urbanization and other landscape factors on gene flow. Levels of genetic diversity were similar for the Western Slope and Front Range, but effective population sizes were smaller, genetic distances were higher, and there was more admixture in the more urbanized Front Range. Forest cover was strongly positively associated with puma gene flow on the Western Slope, while impervious surfaces restricted gene flow and more open, natural habitats enhanced gene flow on the Front Range. Landscape genomic analyses revealed differences in puma movement and gene flow patterns in rural versus urban settings. Our results highlight the utility of dense, genome-scale markers to document subtle impacts of urbanization on a wide-ranging carnivore living near a large urban center.


Asunto(s)
Flujo Génico/genética , Variación Genética/genética , Conducta Predatoria/fisiología , Animales , Ecosistema , Bosques , Genoma/genética , Genotipo , Humanos , Polimorfismo de Nucleótido Simple/genética , Densidad de Población , Puma/genética , Urbanización
3.
Ecol Appl ; 29(3): e01868, 2019 04.
Artículo en Inglés | MEDLINE | ID: mdl-30892753

RESUMEN

Extinction risk is elevated in small, isolated populations due to demographic and genetic interactions. Therefore, it is critical to model these processes realistically in population viability analyses (PVA) to inform local management and contribute to a greater understanding of mechanisms within the extinction vortex. We conducted PVA's for two small mountain lion populations isolated by urbanization in southern California to predict population growth, extinction probability, and loss of genetic diversity with empirical data. Specifically, we (1) provide the first PVA for isolated mountain lions in the Santa Ana Mountains (SAM) that considers both demographic and genetic risk factors and (2) test the hypothesis that variation in abundance and mortality between the SAM and Santa Monica Mountains (SMM) result in differences in population growth, loss of heterozygosity, and extinction probability. Our models predicted 16-21% probability of local extinction in the SAM due purely to demographic processes over 50 yr with current low levels or no immigration. Our models also predicted that genetic diversity will further erode in the SAM such that concern regarding inbreeding depression is warranted unless gene flow is increased, and that if inbreeding depression occurs, rapid local extinction will be highly likely. Dynamics of the two populations were broadly similar, but they also exhibited differences driven by larger population size and higher mortality in the SAM. Density-independent scenarios predicted a rapidly increasing population in the SMM, whereas growth potential did not differ from a stable trend in the SAM. Demographic extinction probability and loss of heterozygosity were greater in the SMM for density-dependent scenarios without immigration. However, higher levels of immigration had stronger, positive influences on both demographic viability and retention of genetic diversity in the SMM driven by lower abundance and higher adult survival. Our results elucidate demographic and genetic threats to small populations within the extinction vortex, and how these vary relative to demographic structure. Importantly, simulating seemingly attainable increases in connectivity was sufficient to greatly reduce extinction probability. Our work highlights that conservation of large carnivores is achievable within urbanized landscapes, but requires land protection, connectivity, and strategies to promote coexistence with humans.


Asunto(s)
Puma , Urbanización , Animales , California , Demografía , Flujo Génico , Variación Genética , Humanos , Dinámica Poblacional
4.
Biol Lett ; 13(3)2017 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-28330975

RESUMEN

Many ecological aspects of tool-use in sea otters are similar to those in Indo-Pacific bottlenose dolphins. Within an area, most tool-using dolphins share a single mitochondrial haplotype and are more related to each other than to the population as a whole. We asked whether sea otters in California showed similar genetic patterns by sequencing mitogenomes of 43 otters and genotyping 154 otters at 38 microsatellite loci. There were six variable sites in the mitogenome that yielded three haplotypes, one found in only a single individual. The other two haplotypes contained similar percentages (33 and 36%) of frequent tool-users and a variety of diet types. Microsatellite analyses showed that snail specialists, the diet specialist group that most frequently used tools, were no more related to each other than to the population as a whole. The lack of genetic association among tool-using sea otters compared with dolphins may result from the length of time each species has been using tools. Tool-use in dolphins appears to be a relatively recent innovation (less than 200 years) but sea otters have probably been using tools for many thousands or even millions of years.


Asunto(s)
Nutrias/fisiología , Comportamiento del Uso de la Herramienta , Animales , California , Dieta/veterinaria , Genoma Mitocondrial , Haplotipos , Repeticiones de Microsatélite , Nutrias/genética
5.
Proc Biol Sci ; 283(1837)2016 Aug 31.
Artículo en Inglés | MEDLINE | ID: mdl-27581877

RESUMEN

The extinction vortex is a theoretical model describing the process by which extinction risk is elevated in small, isolated populations owing to interactions between environmental, demographic, and genetic factors. However, empirical demonstrations of these interactions have been elusive. We modelled the dynamics of a small mountain lion population isolated by anthropogenic barriers in greater Los Angeles, California, to evaluate the influence of demographic, genetic, and landscape factors on extinction probability. The population exhibited strong survival and reproduction, and the model predicted stable median population growth and a 15% probability of extinction over 50 years in the absence of inbreeding depression. However, our model also predicted the population will lose 40-57% of its heterozygosity in 50 years. When we reduced demographic parameters proportional to reductions documented in another wild population of mountain lions that experienced inbreeding depression, extinction probability rose to 99.7%. Simulating greater landscape connectivity by increasing immigration to greater than or equal to one migrant per generation appears sufficient to largely maintain genetic diversity and reduce extinction probability. We provide empirical support for the central tenet of the extinction vortex as interactions between genetics and demography greatly increased extinction probability relative to the risk from demographic and environmental stochasticity alone. Our modelling approach realistically integrates demographic and genetic data to provide a comprehensive assessment of factors threatening small populations.


Asunto(s)
Genética de Población , Puma/genética , Animales , Los Angeles , Dinámica Poblacional , Probabilidad
6.
Parasitol Res ; 115(9): 3557-65, 2016 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-27189064

RESUMEN

Leucocytozoon, a widespread hemosporidian blood parasite that infects a broad group of avian families, has been studied in corvids (family: Corvidae) for over a century. Current taxonomic classification indicates that Leucocytozoon sakharoffi infects crows and related Corvus spp., while Leucocytozoon berestneffi infects magpies (Pica spp.) and blue jays (Cyanocitta sp.). This intrafamily host specificity was based on the experimental transmissibility of the parasites, as well as slight differences in their morphology and life cycle development. Genetic sequence data from Leucocytozoon spp. infecting corvids is scarce, and until the present study, sequence data has not been analyzed to confirm the current taxonomic distinctions. Here, we predict the phylogenetic relationships of Leucocytozoon cytochrome b lineages recovered from infected American Crows (Corvus brachyrhynchos), yellow-billed magpies (Pica nuttalli), and Steller's jays (Cyanocitta stelleri) to explore the host specificity pattern of L. sakharoffi and L. berestneffi. Phylogenetic reconstruction revealed a single large clade containing nearly every lineage recovered from the three host species, while showing no evidence of the expected distinction between L. sakharoffi and L. berestneffi. In addition, five of the detected lineages were recovered from both crows and magpies. This absence of the previously described host specificity in corvid Leucocytozoon spp. suggests that L. sakharoffi and L. berestneffi be reexamined from a taxonomic perspective.


Asunto(s)
Cuervos/parasitología , Haemosporida/clasificación , Haemosporida/genética , Especificidad del Huésped/genética , Infecciones Protozoarias en Animales/parasitología , Animales , Secuencia de Bases , Citocromos b/genética , ADN Protozoario/genética , Haemosporida/enzimología , Filogenia , Análisis de Secuencia de ADN
8.
Annu Rev Anim Biosci ; 12: 161-185, 2024 Feb 15.
Artículo en Inglés | MEDLINE | ID: mdl-38358836

RESUMEN

Hummingbirds share biologically distinctive traits: sustained hovering flight, the smallest bird body size, and high metabolic rates fueled partially by nectar feeding that provides pollination to plant species. Being insectivorous and sometimes serving as prey to larger birds, they fulfill additional important ecological roles. Hummingbird species evolved and radiated into nearly every habitat in the Americas, with a core of species diversity in South America. Population declines of some of their species are increasing their risk of extinction. Threats to population health and genetic diversity are just beginning to be identified, including diseases and hazards caused by humans. We review the disciplines of population health, disease ecology, and genomics as they relate to hummingbirds. We appraise knowledge gaps, causes of morbidity and mortality including disease, and threats to population viability. Finally, we highlight areas of research need and provide ideas for future studies aimed at facilitating hummingbird conservation.


Asunto(s)
Néctar de las Plantas , Polinización , Humanos , Animales , Aves/genética , Genómica
9.
J Wildl Dis ; 60(2): 496-501, 2024 04 01.
Artículo en Inglés | MEDLINE | ID: mdl-38287919

RESUMEN

As chronic wasting disease (CWD) continues to spread across North America, the relationship between CWD and host genetics has become of interest. In Rocky Mountain elk (Cervus elaphus nelsoni), one or two copies of a leucine allele at codon 132 of the prion protein gene (132L*) has been shown to prolong the incubation period of CWD. Our study examined the relationship between CWD epidemiology and codon 132 evolution in elk from Wyoming, USA, from 2011 to 2018. Using PCR and Sanger sequencing, we genotyped 997 elk and assessed the relationship between genotype and CWD prevalence estimated from surveillance data. Using logistic regression, we showed that each 1% increase in CWD prevalence is associated with a 9.6% increase in the odds that an elk would have at least one copy of leucine at codon 132. In some regions, however, 132L* variants were found in the absence of CWD, indicating that evolutionary and epidemiologic patterns can be heterogeneous across space and time. We also provide evidence that naturally occurring CWD is not rare in 132L* elk, which merits the study of shedding kinetics in 132L* elk and the influence of genotype on CWD strain diversity. The management implications of cervid adaptations to CWD are difficult to predict. Studies that investigate the degree to which evolutionary outcomes are shaped by host spatial structure can provide useful epidemiologic insight, which can in turn aid management by informing scale and extent of mitigation actions.


Asunto(s)
Ciervos , Priones , Enfermedad Debilitante Crónica , Animales , Enfermedad Debilitante Crónica/epidemiología , Enfermedad Debilitante Crónica/genética , Proteínas Priónicas/genética , Proteínas Priónicas/metabolismo , Leucina/genética , Leucina/metabolismo , Codón/metabolismo , Ciervos/metabolismo
10.
Int J Mol Sci ; 13(12): 16592-7, 2012 Dec 05.
Artículo en Inglés | MEDLINE | ID: mdl-23443120

RESUMEN

The domestic ferret (Mustela putorius furo) is an important model organism for the study of avian influenza and other diseases of humans and animals, as well as a popular pet animal. In order to evaluate genetic diversity and study disease relationships in ferrets, 22 nuclear microsatellite loci (17 dinucleotide and 5 tetranucleotide) were developed from ferret genomic libraries and organized into seven multiplex sets. Polymorphism was preliminarily assessed in one population in Australia and one in the USA, sampled with 25 individuals each. The loci displayed allelic diversity ranging from 1 to 5 alleles, and expected and observed heterozygosities ranging from 0.04 to 0.65 and 0.04 to 0.76, respectively. Additionally, the loci amplified products in 15 samples from the wild ancestor, European polecat (Mustela putorius) and domestic ferret-polecat hybrids. In polecat/hybrid samples, allelic diversity ranged from 3 to 8 alleles, and expected and observed heterozygosities ranged from 0.13 to 0.81 and 0.13 to 0.80 respectively. These markers will be useful for molecular assessments of genetic diversity and applications to evolution, ecology, and health in domestic ferrets and wild polecats.


Asunto(s)
Alelos , Hurones/genética , Sitios Genéticos , Repeticiones de Microsatélite , Polimorfismo Genético , Animales , Australia , Estados Unidos
11.
Evol Appl ; 15(2): 286-299, 2022 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-35233248

RESUMEN

Urbanization is decreasing wildlife habitat and connectivity worldwide, including for apex predators, such as the puma (Puma concolor). Puma populations along California's central and southern coastal habitats have experienced rapid fragmentation from development, leading to calls for demographic and genetic management. To address urgent conservation genomic concerns, we used double-digest restriction-site associated DNA (ddRAD) sequencing to analyze 16,285 genome-wide single-nucleotide polymorphisms (SNPs) from 401 pumas sampled broadly across the state. Our analyses indicated support for 4-10 geographically nested, broad- to fine-scale genetic clusters. At the broadest scale, the four genetic clusters had high genetic diversity and exhibited low linkage disequilibrium, indicating that pumas have retained genomic diversity statewide. However, multiple lines of evidence indicated substructure, including 10 finer-scale genetic clusters, some of which exhibited fixed alleles and linkage disequilibrium. Fragmented populations along the Southern Coast and Central Coast had particularly low genetic diversity and strong linkage disequilibrium, indicating genetic drift and close inbreeding. Our results demonstrate that genetically at risk populations are typically nested within a broader-scale group of interconnected populations that collectively retain high genetic diversity and heterogenous fixations. Thus, extant variation at the broader scale has potential to restore diversity to local populations if management actions can enhance vital gene flow and recombine locally sequestered genetic diversity. These state- and genome-wide results are critically important for science-based conservation and management practices. Our nested population genomic analysis highlights the information that can be gained from population genomic studies aiming to provide guidance for the conservation of fragmented populations.

12.
J Wildl Dis ; 58(1): 63-75, 2022 01 01.
Artículo en Inglés | MEDLINE | ID: mdl-34818404

RESUMEN

Southern sea otter (Enhydra lutris nereis) population recovery is influenced by a variety of factors, including predation, biotoxin exposure, infectious disease, oil spills, habitat degradation, and resource limitation. This population has also experienced a significant genetic bottleneck, resulting in low genetic diversity. We investigated how two metrics, familial relatedness and genetic diversity, are correlated with common causes of mortality in southern sea otters, including cardiomyopathy, acanthocephalan (Profilicollis spp.) peritonitis, systemic protozoal infection (Toxoplasma gondii and Sarcocystis neurona), domoic acid intoxication, end-lactation syndrome, and shark bite. Microsatellite genetic markers were used to examine this association in 356 southern sea otters necropsied from 1998 to 2012. Significant associations with genetic diversity or familial relatedness (P<0.05) were observed for cardiomyopathy, acanthocephalan peritonitis, and sarcocystosis, and these associations varied by sex. Adult male cardiomyopathy cases (n=86) were more related than the null expectation (P<0.049). Conversely, female acanthocephalan peritonitis controls (n=110) were more related than the null expectation (P<0.004). Including genetic diversity as a predictor for fatal acanthocephalan peritonitis in the multivariate logistic model significantly improved model fit; lower genetic diversity was associated with reduced odds of sea otter death due to acanthocephalan peritonitis. Finally, male sarcocystosis controls (n=158) were more related than the null expectation (P<0.011). Including genetic diversity in the multivariate logistic model for fatal S. neurona infection improved model fit; lower genetic diversity was associated with increased odds of sea otter death due to S. neurona. Our study suggests that genetic diversity and familial relatedness, in conjunction with other factors such as age and sex, may influence outcome (survival or death) in relation to several common southern sea otter diseases. Our findings can inform policy for conservation management, such as potential reintroduction efforts, as part of species recovery.


Asunto(s)
Nutrias , Sarcocystis , Sarcocistosis , Toxoplasma , Animales , Femenino , Variación Genética , Masculino , Sarcocystis/genética , Sarcocistosis/veterinaria , Toxoplasma/genética
13.
Front Vet Sci ; 9: 924854, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-36090172

RESUMEN

Avian pox is a common avian virus that in its cutaneous form can cause characteristic lesions on a bird's dermal surfaces. Detection of avian pox in free-ranging birds historically relied on observations of visual lesions and/or histopathology, both which can underestimate avian pox prevalence. We compared traditional visual observation methods for avian pox with molecular methods that utilize minimally invasive samples (blood, toenail clipping, feathers, and dermal swabs) in an ecologically important group of birds, hummingbirds. Specifically, avian pox prevalence in several species of hummingbirds were examined across multiple locations using three different methods: (1) visual inspection of hummingbirds for pox-like lesions from a long-term banding data set, (2) qPCR assay of samples from hummingbird carcasses from wildlife rehabilitation centers, and (3) qPCR assay of samples from live-caught hummingbirds. A stark difference in prevalences among these three methods was identified, with an avian pox prevalence of 1.5% from banding data, 20.4% from hummingbird carcasses, and 32.5% from live-caught hummingbirds in California. This difference in detection rates underlines the necessity of a molecular method to survey for avian pox, and this study establishes one such method that could be applied to other wild bird species. Across all three methods, Anna's hummingbirds harbored significantly higher avian pox prevalence than other species examined, as did males compared with females and birds caught in Southern California compared with Northern California. After hatch-year hummingbirds also harbored higher avian pox prevalences than hatch-year hummingbirds in the California banding data set and the carcass data set. This is the first study to estimate the prevalence of avian pox in hummingbirds and address the ecology of this hummingbird-specific strain of avian pox virus, providing vital information to inform future studies on this charismatic and ecologically important group of birds.

14.
BMC Evol Biol ; 11: 143, 2011 May 25.
Artículo en Inglés | MEDLINE | ID: mdl-21612651

RESUMEN

BACKGROUND: Genes at the major histocompatibility complex (MHC) are known for high levels of polymorphism maintained by balancing selection. In small or bottlenecked populations, however, genetic drift may be strong enough to overwhelm the effect of balancing selection, resulting in reduced MHC variability. In this study we investigated MHC evolution in two recently diverged bird species: the endemic Galápagos hawk (Buteo galapagoensis), which occurs in small, isolated island populations, and its widespread mainland relative, the Swainson's hawk (B. swainsoni). RESULTS: We amplified at least two MHC class II B gene copies in each species. We recovered only three different sequences from 32 Galápagos hawks, while we amplified 20 unique sequences in 20 Swainson's hawks. Most of the sequences clustered into two groups in a phylogenetic network, with one group likely representing pseudogenes or nonclassical loci. Neutral genetic diversity at 17 microsatellite loci was also reduced in the Galápagos hawk compared to the Swainson's hawk. CONCLUSIONS: The corresponding loss in neutral diversity suggests that the reduced variability present at Galápagos hawk MHC class II B genes compared to the Swainson's hawk is primarily due to a founder event followed by ongoing genetic drift in small populations. However, purifying selection could also explain the low number of MHC alleles present. This lack of variation at genes involved in the adaptive immune response could be cause for concern should novel diseases reach the archipelago.


Asunto(s)
Genes MHC Clase II , Halcones/genética , Halcones/inmunología , Polimorfismo Genético , Secuencia de Aminoácidos , Animales , Ecuador , Exones , Genética de Población , Datos de Secuencia Molecular , Filogenia , Selección Genética , Alineación de Secuencia
15.
R Soc Open Sci ; 8(8): 210802, 2021 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-34430048

RESUMEN

Infectious diseases play an important role in wildlife population dynamics by altering individual fitness, but detecting disease-driven natural selection in free-ranging populations is difficult due to complex disease-host relationships. Chronic wasting disease (CWD) is a fatal infectious prion disease in cervids for which mutations in a single gene have been mechanistically linked to disease outcomes, providing a rare opportunity to study disease-driven selection in wildlife. In Wyoming, USA, CWD has gradually spread across mule deer (Odocoileus hemionus) populations, producing natural variation in disease history to evaluate selection pressure. We used spatial variation and a novel temporal comparison to investigate the relationship between CWD and a mutation at codon 225 of the mule deer prion protein gene that slows disease progression. We found that individuals with the 'slow' 225F allele were less likely to test positive for CWD, and the 225F allele was more common in herds exposed to CWD longer. We also found that in the past 2 decades, the 225F allele frequency increased more in herds with higher CWD prevalence. This study expanded on previous research by analysing spatio-temporal patterns of individual and herd-based disease data to present multiple lines of evidence for disease-driven selection in free-ranging wildlife.

16.
Commun Biol ; 4(1): 12, 2021 01 04.
Artículo en Inglés | MEDLINE | ID: mdl-33398025

RESUMEN

Urban expansion can fundamentally alter wildlife movement and gene flow, but how urbanization alters pathogen spread is poorly understood. Here, we combine high resolution host and viral genomic data with landscape variables to examine the context of viral spread in puma (Puma concolor) from two contrasting regions: one bounded by the wildland urban interface (WUI) and one unbounded with minimal anthropogenic development (UB). We found landscape variables and host gene flow explained significant amounts of variation of feline immunodeficiency virus (FIV) spread in the WUI, but not in the unbounded region. The most important predictors of viral spread also differed; host spatial proximity, host relatedness, and mountain ranges played a role in FIV spread in the WUI, whereas roads might have facilitated viral spread in the unbounded region. Our research demonstrates how anthropogenic landscapes can alter pathogen spread, providing a more nuanced understanding of host-pathogen relationships to inform disease ecology in free-ranging species.


Asunto(s)
Virus de la Inmunodeficiencia Felina/genética , Infecciones por Lentivirus/veterinaria , Puma/microbiología , Urbanización , Animales , Colorado/epidemiología , Femenino , Flujo Génico , Infecciones por Lentivirus/epidemiología , Infecciones por Lentivirus/transmisión , Masculino , Filogeografía , Puma/genética
17.
BMC Evol Biol ; 10: 224, 2010 Jul 22.
Artículo en Inglés | MEDLINE | ID: mdl-20650000

RESUMEN

BACKGROUND: Phenotypic and molecular genetic data often provide conflicting patterns of intraspecific relationships confounding phylogenetic inference, particularly among birds where a variety of environmental factors may influence plumage characters. Among diurnal raptors, the taxonomic relationship of Buteo jamaicensis harlani to other B. jamaicensis subspecies has been long debated because of the polytypic nature of the plumage characteristics used in subspecies or species designations. RESULTS: To address the evolutionary relationships within this group, we used data from 17 nuclear microsatellite loci, 430 base pairs of the mitochondrial control region, and 829 base pairs of the melanocortin 1 receptor (Mc1r) to investigate molecular genetic differentiation among three B. jamaicensis subspecies (B. j. borealis, B. j. calurus, B. j. harlani). Bayesian clustering analyses of nuclear microsatellite loci showed no significant differences between B. j. harlani and B. j. borealis. Differences observed between B. j. harlani and B. j. borealis in mitochondrial and microsatellite data were equivalent to those found between morphologically similar subspecies, B. j. borealis and B. j. calurus, and estimates of migration rates among all three subspecies were high. No consistent differences were observed in Mc1r data between B. j. harlani and other B. jamaicensis subspecies or between light and dark color morphs within B. j. calurus, suggesting that Mc1r does not play a significant role in B. jamaicensis melanism. CONCLUSIONS: These data suggest recent interbreeding and gene flow between B. j. harlani and the other B. jamaicensis subspecies examined, providing no support for the historical designation of B. j. harlani as a distinct species.


Asunto(s)
Evolución Molecular , Flujo Génico , Filogenia , Polimorfismo Genético , Rapaces/genética , Animales , Teorema de Bayes , Núcleo Celular/genética , Análisis por Conglomerados , ADN Mitocondrial/genética , Plumas/fisiología , Geografía , Repeticiones de Microsatélite , Modelos Genéticos , Receptor de Melanocortina Tipo 1/genética , Análisis de Secuencia de ADN , Especificidad de la Especie
18.
Mol Phylogenet Evol ; 56(1): 212-21, 2010 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-20193768

RESUMEN

Investigations of regional genetic differentiation are essential for describing phylogeographic patterns and informing management efforts for species of conservation concern. In this context, we investigated genetic diversity and evolutionary relationships among great gray owl (Strix nebulosa) populations in western North America, which includes an allopatric range in the southern Sierra Nevada in California. Based on a total dataset consisting of 30 nuclear microsatellite DNA loci and 1938-base pairs of mitochondrial DNA, we found that Pacific Northwest sampling groups were recovered by frequency and Bayesian analyses of microsatellite data and each population sampled, except for western Canada, showed evidence of recent population bottlenecks and low effective sizes. Bayesian and maximum likelihood phylogenetic analyses of sequence data indicated that the allopatric Sierra Nevada population is also a distinct lineage with respect to the larger species range in North America; we suggest a subspecies designation for this lineage should be considered (Strix nebulosa yosemitensis). Our study underscores the importance of phylogeographic studies for identifying lineages of conservation concern, as well as the important role of Pleistocene glaciation events in driving genetic differentiation of avian fauna.


Asunto(s)
Evolución Molecular , Variación Genética , Genética de Población , Filogenia , Estrigiformes/genética , Animales , Teorema de Bayes , California , Canadá , Análisis por Conglomerados , Conservación de los Recursos Naturales , ADN Mitocondrial/genética , Geografía , Haplotipos , Repeticiones de Microsatélite , Modelos Genéticos , Noroeste de Estados Unidos , Análisis de Secuencia de ADN , Estrigiformes/clasificación
19.
Ecol Evol ; 10(19): 10687-10696, 2020 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-33072289

RESUMEN

Jointly considering the ecology (e.g., habitat use) and genetics (e.g., population genetic structure and diversity) of a species can increase understanding of current conservation status and inform future management practices. Previous analyses indicate that mountain lion (Puma concolor) populations in California are genetically structured and exhibit extreme variation in population genetic diversity. Although human development may have fragmented gene flow, we hypothesized the quantity and quality of remaining habitat available would affect the genetic viability of each population. Our results indicate that area of suitable habitat, determined via a resource selection function derived using 843,500 location fixes from 263 radio-collared mountain lions, is strongly and positively associated with population genetic diversity and viability metrics, particularly with effective population size. Our results suggested that contiguous habitat of ≥10,000 km2 may be sufficient to alleviate the negative effects of genetic drift and inbreeding, allowing mountain lion populations to maintain suitable effective population sizes. Areas occupied by five of the nine geographic-genetic mountain lion populations in California fell below this habitat threshold, and two (Santa Monica Area and Santa Ana) of those five populations lack connectivity to nearby populations. Enhancing ecological conditions by protection of greater areas of suitable habitat and facilitating positive evolutionary processes by increasing connectivity (e.g., road-crossing structures) might promote persistence of small or isolated populations. The conservation status of suitable habitat also appeared to influence genetic diversity of populations. Thus, our results demonstrate that both the area and status (i.e., protected or unprotected) of suitable habitat influence the genetic viability of mountain lion populations.

20.
J Mammal ; 101(4): 1061-1071, 2020 Aug 31.
Artículo en Inglés | MEDLINE | ID: mdl-33100929

RESUMEN

Preserving connectivity in the core of a species' range is crucial for long-term persistence. However, a combination of ecological characteristics, social behavior, and landscape features can reduce connectivity among wildlife populations and lead to genetic structure. Pronghorn (Antilocapra americana), for example, exhibit fluctuating herd dynamics and variable seasonal migration strategies, but GPS tracking studies show that landscape features such as highways impede their movements, leading to conflicting hypotheses about expected levels of genetic structure. Given that pronghorn populations declined significantly in the early 1900s, have only partially recovered, and are experiencing modern threats from landscape modification, conserving connectivity among populations is important for their long-term persistence in North America. To assess the genetic structure and diversity of pronghorn in the core of their range, we genotyped 4,949 genome-wide single-nucleotide polymorphisms and 11 microsatellites from 398 individuals throughout the state of Wyoming. We found no evidence of genetic subdivision and minimal evidence of isolation by distance despite a range that spans hundreds of kilometers, multiple mountain ranges, and three interstate highways. In addition, a rare variant analysis using putatively recent mutations found no genetic division between pronghorn on either side of a major highway corridor. Although we found no evidence that barriers to daily and seasonal movements of pronghorn impede gene flow, we suggest periodic monitoring of genetic structure and diversity as a part of management strategies to identify changes in connectivity.

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