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1.
Parasitol Res ; 123(6): 254, 2024 Jun 26.
Artigo em Inglês | MEDLINE | ID: mdl-38922478

RESUMO

The Americas hold the greatest bird diversity worldwide. Likewise, ectoparasite diversity is remarkable, including ticks of the Argasidae and Ixodidae families - commonly associated with birds. Considering that ticks have potential health implications for humans, animals, and ecosystems, we conducted a systematic review to evaluate the effects of bioclimatic, geographic variables, and bird species richness on tick infestation on wild birds across the Americas. We identified 72 articles that met our inclusion criteria and provided data on tick prevalence in wild birds. Using Generalized Additive Models, we assessed the effect of environmental factors, such as habitat type, climatic conditions, bird species richness, and geographic location, on tick infestation. Our findings show that most bird infestation case studies involved immature ticks, such as larvae or nymphs, while adult ticks represented only 13% of case studies. We found birds infested by ticks of the genera Amblyomma (68%), Ixodes (22%), Haemaphysalis (5%), Dermacentor (1%), and Rhipicephalus (0.8%) in twelve countries across the Americas. Our findings revealed that temperature variation and bird species richness were negatively associated with tick infestation, which also varied with geographic location, increasing in mid-latitudes but declining in extreme latitudes. Our results highlight the importance of understanding how environmental and bird community factors influence tick infestation in wild birds across the Americas and the dynamics of tick-borne diseases and their impact on biodiversity.


Assuntos
Doenças das Aves , Aves , Infestações por Carrapato , Animais , Infestações por Carrapato/veterinária , Infestações por Carrapato/epidemiologia , Infestações por Carrapato/parasitologia , Aves/parasitologia , América/epidemiologia , Doenças das Aves/parasitologia , Doenças das Aves/epidemiologia , Animais Selvagens/parasitologia , Ecossistema , Carrapatos/fisiologia , Carrapatos/classificação , Biodiversidade , Meio Ambiente , Prevalência
2.
Parasitol Res ; 123(6): 252, 2024 Jun 26.
Artigo em Inglês | MEDLINE | ID: mdl-38922536

RESUMO

Avian haemosporidians of the genera Plasmodium and Haemoproteus are a group of widely distributed blood parasites that can negatively affect the fitness of their hosts. Colombia contains the greatest diversity of birds on the planet, but knowledge about the associations between haemosporidian and its avifauna is scarce and fragmented. We collected blood samples from 255 birds (203 residents and 52 neotropical migrants) belonging to 27 families and 108 species. The study was conducted in six localities in the inter-Andean valleys of the Cauca and Magdalena rivers. Parasites of the genera Plasmodium and Haemoproteus were identified in the samples by morphological and molecular analysis of a fragment of the mitochondrial gene cyt b. Among the samples, 9.3% (n = 24) were positive for Plasmodium or Haemoproteus. Co-infection with Plasmodium and Haemoproteus was found in Red-eyed Vireo. Seventeen haemosporidian lineages were identified, five of which were reported for the first time in resident birds (Common Ground Dove, Checker-throated Stipplethroat, Tropical Kingbird, Pale-breasted Thrush, and Ruddy-breasted Seedeater) and one in the Summer Tanager (neotropical migrant). The research results confirm the wide diversity of haemosporidian present in tropical lowlands and the possible role of neotropical migratory birds in dissemination on haemosporidian along their migratory routes.


Assuntos
Doenças das Aves , Aves , Haemosporida , Plasmodium , Infecções Protozoárias em Animais , Animais , Colômbia/epidemiologia , Haemosporida/classificação , Haemosporida/isolamento & purificação , Haemosporida/genética , Aves/parasitologia , Doenças das Aves/parasitologia , Doenças das Aves/epidemiologia , Plasmodium/classificação , Plasmodium/isolamento & purificação , Plasmodium/genética , Infecções Protozoárias em Animais/parasitologia , Infecções Protozoárias em Animais/epidemiologia , Citocromos b/genética , Migração Animal , Filogenia , Coinfecção/parasitologia , Coinfecção/veterinária , Coinfecção/epidemiologia
3.
Acta Trop ; 254: 107210, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38599442

RESUMO

Several species of hard ticks, including those of the genera Ixodes, Haemaphysalis, Amblyomma, and Rhipicephalus, are of medical and veterinary importance and have been reported in association with Neotropical wild birds. Colombia, known for its great bird diversity, has 57 confirmed tick species. However, there are few studies on the association between wild birds and ticks in Colombia. The Orinoquia region, a migratory center in Colombia, provides a unique opportunity to study wild bird-tick associations and their implications for tick-borne disease dynamics. Our study, conducted between October and December 2021, aimed to identify hard ticks infesting resident and migratory wild birds in the department of Arauca and to assess the presence of bacteria from the genera Anaplasma, Borrelia, Ehrlichia, Rickettsia, and piroplasms. A total of 383 birds were examined, of which 21 were infested. We collected 147 ticks, including Amblyomma dissimile (larvae), Amblyomma longirostre (nymphs), Amblyomma mixtum (adults), and Amblyomma nodosum (larvae and nymphs). We did not detect bacterial DNA in the tested ticks; however, piroplasm DNA was detected in ticks from three of the infested birds. Of the 21 bird-tick associations, six are new to the Americas, and interesting documentation of piroplasm DNA in A. longirostre, A. nodosum, and A. dissimile ticks from wild birds in the region. This study provides valuable insights into the ticks associated with wild birds and their role in the dispersal of ticks and pathogens in Colombia, enhancing our understanding of tick life cycles and tick-borne disease dynamics.


Assuntos
Animais Selvagens , Doenças das Aves , Aves , Ixodidae , Infestações por Carrapato , Animais , Colômbia , Infestações por Carrapato/veterinária , Infestações por Carrapato/epidemiologia , Aves/parasitologia , Ixodidae/microbiologia , Ixodidae/crescimento & desenvolvimento , Ixodidae/classificação , Animais Selvagens/parasitologia , Animais Selvagens/microbiologia , Doenças das Aves/parasitologia , Doenças das Aves/epidemiologia , Borrelia/isolamento & purificação , Ehrlichia/isolamento & purificação , Rickettsia/isolamento & purificação , Rickettsia/genética , Rickettsia/classificação , Migração Animal , Anaplasma/isolamento & purificação , Anaplasma/genética , Ninfa/microbiologia , Ninfa/crescimento & desenvolvimento , Feminino , Masculino , Larva/microbiologia , Amblyomma/microbiologia
4.
Acta Trop ; 256: 107282, 2024 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-38861832

RESUMO

The hard tick clade (Ixodidae) currently comprises 762 species worldwide (266 Prostriata and 496 Metastriata). A quarter of hard ticks are found in the Neotropical region, and 42 species have been documented in Colombia. Ixodidae species are important vectors of pathogens such as bacteria, helminths, protozoa, and viruses. In tick-borne diseases, vertebrate hosts perform an important role in the transmission, maintenance, and spread of pathogens. Colombia ranks sixth among countries with the highest mammal biodiversity, with a total of 548 species, where some of these species may be involved in pathogen transmission cycles with ticks as vectors. This research evaluated the presence of two genera of bacteria (Borrelia and Rickettsia) and the protozoan (Babesia) in ticks and mammals in the Orinoquia region of Colombia, establishing interaction networks. The information comes from 734 mammals (655 wild and 79 domestic), belonging to 59 species. Tick infestation (n = 1,805) was found with 14.85 % (n = 109) of the examined mammals and corresponds to nine tick species confirmed morphologically and molecularly. To detect pathogens 272 ticks were collected while feeding on 96 mammals; samples from 93 mammals were analyzed. The presence of borreliae from the relapsing fever group (RFG) and the Lyme disease group (LDG) were detected. Rickettsia spp. was detected in ticks and mammals, while Babesia bigemina was only detected in ticks. This research is the first to address the prevalence of zoonotic pathogens in domestic and wild mammals infested with hard ticks in the Department of Arauca, Colombia. Considering that reporting cases of infections with Babesia, Borrelia, and Rickettsia in Colombia is not mandatory, their impact on public health cannot be estimated. This highlights the importance of continuously detecting, confirming, and identifying these and other important pathogens within the "One Health" framework, as they have a significant economic and medical-veterinary impact globally.


Assuntos
Babesia , Borrelia , Interações Hospedeiro-Patógeno , Ixodidae , Mamíferos , Rickettsia , Animais , Colômbia , Mamíferos/parasitologia , Mamíferos/microbiologia , Rickettsia/isolamento & purificação , Rickettsia/genética , Ixodidae/microbiologia , Ixodidae/parasitologia , Babesia/isolamento & purificação , Borrelia/isolamento & purificação , Borrelia/patogenicidade , Infestações por Carrapato/veterinária , Infestações por Carrapato/epidemiologia , Infestações por Carrapato/parasitologia , Doenças Transmitidas por Carrapatos/microbiologia , Doenças Transmitidas por Carrapatos/epidemiologia , Doenças Transmitidas por Carrapatos/transmissão , Doenças Transmitidas por Carrapatos/parasitologia
5.
Int J Parasitol Parasites Wildl ; 24: 100943, 2024 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-38778917

RESUMO

Ticks are obligate hematophagous ectoparasites of vertebrates and are relevant worldwide due to the number of bacterial and other pathogens they can transmit. To date, the knowledge about the microorganisms that ticks harbor and transmit to their hosts is incipient. In this study, 24 samples of mammals belonging to four taxonomic orders and ticks of the genera Amblyomma and Rhipicephalus from the Orinoco region of Colombia were analyzed to described and compare the bacterial microbiome. Genetic extraction was performed, and the V3-V4 region of the 16S rRNA gene was amplified by PCR. Libraries were created, and those samples with adequate quality indices were sequenced using Illumina MiSeq technology. Bacterial taxonomic assignment analyses were conducted through Amplicon Sequence Variants (ASVs) and Operational Taxonomic Units (OTUs). The results correspond to 16 samples that passed the quality filters, with 3218 OTUs (415 families). Although a considerable number of unknown bacteria was found, Enterobacteriaceae, Beijerinckiaceae, Moraxellaceae, and Burkholderiaceae are the most prevalent families, and the presence of the genera Coxiella, Escherichia-Shigella, Enterobacter, which can harbor pathogenic species was confirmed. In individuals of Amblyomma mixtum found actively feeding on Hydrochoerus hydrochaeris, bacteria of the genera Escherichia-Shigella and Enterobacter were documented. Similarly, Rhipicephalus microplus found actively feeding on Odocoileus virginianus cariacou shared Escherichia-Shigella. Ralstonia was shared among the blood samples of H. hydrochaeris, while Anaplasma and Eubacterium were shared in blood and liver samples of O. v. cariacou. Shared bacteria between A. mixtum and R. microplus included Bacillus, Coxiella, and Escherichia-Shigella. The results highlight the need of additional studies in other natural regions of Colombia and other American countries where tick-borne diseases have been detected. Likewise, the recorded data are the first at the level of bacterial communities in ticks of the family Ixodidae and provide valuable knowledge for the understanding host-tick and pathogen interactions.

6.
Ticks Tick Borne Dis ; 15(6): 102381, 2024 Jul 08.
Artigo em Inglês | MEDLINE | ID: mdl-38981408

RESUMO

Ticks are a globally distributed group of hematophagous ectoparasites that parasitize terrestrial vertebrates such as amphibians, reptiles, birds, and mammals. Ticks are vectors and reservoirs of pathogens that play an important role in wildlife and human health. Rickettsia is one of the bacteria transmitted by ticks, which some pathogenic species can cause rickettsiosis, a zoonotic disease that can cause serious harm to humans and animals. More information is necessary on the interactions between ticks and wildlife despite the fifty-seven ticks species already identified in Colombia. The objective of the present study was to determine the associations between ticks parasitizing wildlife and bacteria of the genus Rickettsia in six departments of Colombia. One hundred eighty-five ticks (80 larvae, 78 nymphs, and 27 adults) were collected from 55 wildlife species (amphibians, birds, mammals, and reptiles). Nine tick species were identified, and Rickettsia bellii, Rickettsia felis, 'Candidatus Rickettsia colombianensi' and Rickettsia parkeri were detected. Our results contribute to the current knowledge of tick-associated rickettsiae and the role of wildlife in their transmission dynamics.

7.
Zookeys ; 1196: 149-175, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38566619

RESUMO

The genus Rhinella (Bufonidae) comprises 92 species of Neotropical toads. In Colombia, Rhinella is represented by 22 recognized species, of which nine belong to the Rhinellafestae group. Over the past decade, there has been increasing evidence of cryptic diversity within this group, particularly in the context of Andean forms. Specimens of Rhinella collected in high Andean forests on both slopes of the Central Cordillera in Colombia belong to an undescribed species, Rhinellakumandaysp. nov. Genetic analyses using the mitochondrial 16S rRNA gene indicated that the individuals belong to the festae species group. However, they can be distinguished from other closely related species such as Rhinellaparaguas and Rhinellatenrec by a combination of morphological traits including the presence of tarsal fold, a moderate body size, and substantial genetic divergence in the 16S rRNA gene (> 5%). Through this integrative approach, the specimens from the Central Cordillera of Colombia are considered an evolutionary divergent lineage that is sister to R.paraguas, and described as a new species. Rhinellakumandaysp. nov. is restricted to the Central Cordillera of Colombia inhabiting both slopes in the departments of Caldas and Tolima, in an elevational range between 2420 and 3758 m. With the recognition of this new species, the genus Rhinella now comprises 93 species with 23 of them found in Colombia, and ten species endemic to the country.

8.
Parasit Vectors ; 17(1): 139, 2024 Mar 18.
Artigo em Inglês | MEDLINE | ID: mdl-38500136

RESUMO

BACKGROUND: Amblyomma is the third most diversified genus of Ixodidae that is distributed across the Indomalayan, Afrotropical, Australasian (IAA), Nearctic and Neotropical biogeographic ecoregions, reaching in the Neotropic its highest diversity. There have been hints in previously published phylogenetic trees from mitochondrial genome, nuclear rRNA, from combinations of both and morphology that the Australasian Amblyomma or the Australasian Amblyomma plus the Amblyomma species from the southern cone of South America, might be sister-group to the Amblyomma of the rest of the world. However, a stable phylogenetic framework of Amblyomma for a better understanding of the biogeographic patterns underpinning its diversification is lacking. METHODS: We used genomic techniques to sequence complete and nearly complete mitochondrial genomes -ca. 15 kbp- as well as the nuclear ribosomal cluster -ca. 8 kbp- for 17 Amblyomma ticks in order to study the phylogeny and biogeographic pattern of the genus Amblyomma, with particular emphasis on the Neotropical region. The new genomic information generated here together with genomic information available on 43 ticks (22 other Amblyomma species and 21 other hard ticks-as outgroup-) were used to perform probabilistic methods of phylogenetic and biogeographic inferences and time-tree estimation using biogeographic dates. RESULTS: In the present paper, we present the strongest evidence yet that Australasian Amblyomma may indeed be the sister-group to the Amblyomma of the rest of the world (species that occur mainly in the Neotropical and Afrotropical zoogeographic regions). Our results showed that all Amblyomma subgenera (Cernyomma, Anastosiella, Xiphiastor, Adenopleura, Aponomma and Dermiomma) are not monophyletic, except for Walkeriana and Amblyomma. Likewise, our best biogeographic scenario supports the origin of Amblyomma and its posterior diversification in the southern hemisphere at 47.8 and 36.8 Mya, respectively. This diversification could be associated with the end of the connection of Australasia and Neotropical ecoregions by the Antarctic land bridge. Also, the biogeographic analyses let us see the colonization patterns of some neotropical Amblyomma species to the Nearctic. CONCLUSIONS: We found strong evidence that the main theater of diversification of Amblyomma was the southern hemisphere, potentially driven by the Antarctic Bridge's intermittent connection in the late Eocene. In addition, the subgeneric classification of Amblyomma lacks evolutionary support. Future studies using denser taxonomic sampling may lead to new findings on the phylogenetic relationships and biogeographic history of Amblyomma genus.


Assuntos
Genoma Mitocondrial , Ixodidae , Carrapatos , Animais , Ixodidae/genética , Filogenia , Amblyomma
9.
Zookeys ; 1180: 237-256, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-38312325

RESUMO

The genus Molossops includes two monotypic species of insectivore bats distributed in South America: Molossopsneglectus and Molossopstemminckii. Both can be differentiated, based on sizes, M.temminckii being smaller (forearm less than 33 mm). Despite being monotypic, at least two additional subspecies have been described for M.temminckii, of which M.temminckiigriseiventer from the inter-Andean Valley of the Magdalena River in Colombia might represent a valid taxon. To test the taxonomic status of M.t.griseiventer, we reviewed specimens of M.temminckii from cis- and trans-Andean localities in Colombia. We used Cytochrome-b and Cytochrome Oxidase I comparisons to test the phylogenetic position of cis- and trans-Andean samples and compared qualitative morphology, morphometric and bioacoustics. Our results show that M.t.griseiventer is differentiated from cis-Andean specimens, providing further evidence of its validity at the species level. Furthermore, M.temminckii (sensu stricto) is also distributed in Colombia, but both M.griseiventer and M.temminckii are allopatric, with the Andes acting as a barrier. The specific identity of the specimens from the Caribbean Region of Colombia needs a new evaluation, but our results clearly show that the diversity of Molossops is underestimated.

10.
Zookeys ; 1180: 145-157, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-38318424

RESUMO

The western or desert red bat, Lasiurusfrantzii, is a cryptic insectivore species distributed in the Neotropics from Mexico south through Central America to Panama. L.frantzii was long considered a subspecies of the red bat, Lasiurusblossevillii, but recently it was elevated to full-species status based on genetic information. Here we present evidence of the presence of L.frantzii in the Andean Region of Colombia, confirming the species' presence in South America; the new record, from 3836 m a.s.l., is also the highest elevation known for the species. We suggest that L.frantzii might be widely distributed in trans-Andean areas of Colombia, Ecuador, Venezuela, and perhaps Peru and Bolivia. However, a review and exploration of additional morphological traits to identify the species are necessary because of the uncertainty of the distribution of L.frantzii.

11.
rev. udca actual. divulg. cient ; 25(1): e1850, ene.-jun. 2022. tab, graf
Artigo em Inglês | LILACS-Express | LILACS | ID: biblio-1395191

RESUMO

ABSTRACT The northern region of the Caldas department in Colombia is considered an endemic area for murine typhus. Recent studies in patients with acute febrile disease demonstrated infection with the spotted fever group's rickettsiae due to an increase in the IgG titer by indirect immunofluorescence in paired sera obtained from these patients. The objective of the current research was to identify the species of ticks present in domestic animals in the northern region of Caldas and establish the presence of rickettsial genomic material in the collected ticks. Ticks were obtained from bovines, horses, and dogs in seven municipalities in the north of Caldas. Ticks were stored in 90 % ethanol until processing and were identified using taxonomic keys, DNA was extracted using commercial techniques, and the gltA gene was amplified by conventional chain reaction polymerase (PCR). Seven hundred thirteen ticks were obtained from 593 domestic animals. The highest infestation occurred in cattle, followed by canines and horses. Ticks found corresponded to the species Riphicephalus microplus, Dermacentor nitens, Amblyomma sp., and Riphicephalus sanguineus s.l. In none of the tick samples, Rickettsia-specific gltA gene DNA was found. It can be inferred that the ticks obtained are not a source of rickettsial infection for people in this department region, despite finding different species associated with the transmission of this disease.


RESUMEN La región norte del departamento de Caldas, Colombia es considerada como una zona endémica de tifo murino. Estudios recientes realizados en pacientes con enfermedad febril aguda, demostraron la infección con rickettsias, del grupo de las fiebres manchadas, debido al aumento en el título de IgG, por inmunofluorescencia indirecta (IFI), en sueros pareados, obtenidos de dichos pacientes. El objetivo de la investigación fue el de identificar las especies de garrapatas presentes en animales domésticos, de la región norte de Caldas y establecer la presencia de material genómico de rickettsias, en las garrapatas recolectadas. En siete municipios, se recolectaron garrapatas de bovinos, de equinos y de caninos. Las garrapatas, se almacenaron en etanol al 90 %, hasta su identificación taxonómica. Se extrajo el ADN, utilizando técnicas comerciales y se amplificó por reacción de cadena de la polimerasa (PCR) convencional el gen gltA. Se obtuvieron 713 garrapatas de 593 animales domésticos. La más alta infestación se presentó en bovinos, seguido de los caninos y equinos. Las garrapatas encontradas correspondieron a las especies Riphicephalus microplus, Dermacentor nitens, Amblyomma sp. y Riphicephalus sanguineus s.l. En ninguna de las muestras, se comprobó la presencia de ADN del gen gltA específico de Rickettsia. Se puede inferir que las garrapatas obtenidas no serían una fuente de infección rickettsial para las personas, en esta región del departamento; sin embargo, su presencia es un factor de riesgo para la adquisición de rickettsiosis asociadas con las fiebres manchadas.

12.
Biota Neotrop. (Online, Ed. ingl.) ; 21(1): e20200985, 2021. tab, graf
Artigo em Inglês | LILACS-Express | LILACS | ID: biblio-1142470

RESUMO

Abstract: Breeding biology in a population of Rufous-collared Sparrow (Zonotrichia capensis, Statius Müller, 1776) at different elevations in the Tropical Andes. Elevation strongly influences the evolution of life history traits associated with bird physiology and reproduction. Since life history traits in birds are modulated by environmental factors that vary with elevation, we expected to find changes in breeding biology traits of Z. capensis at different elevations. In this study, we compared the breeding biology (clutch size, egg volume, and reproductive activity) of a non-migratory population of Z. capensis in two localities at different elevations (low and high elevations, 1 800 m a.s.l., and 3 800 m a.s.l., respectively) and same latitude in the Colombian Tropical Andes for a one-year period. We found no differences in clutch size between the localities; however, egg volume was higher at high elevation. Furthermore, the reproductive activity differed significantly between localities. We propose that clutch size is likely conserved throughout the altitudinal distribution of Z. capensis since the species evolved in Tropical lowlands. On the other hand, the larger egg volume at high elevation could obey local environmental factors that may favor the reproductive success of the population.


Resumen: Biología reproductiva en una población de Gorrión Copetón (Zonotrichia capensis, Statius Müller, 1776) a diferente elevación en los Andes tropicales. La elevación influye fuertemente en la evolución de los rasgos de historia de vida asociados con la fisiología y reproducción de las aves. Dado que los rasgos de historia de vida en las aves están modulados por factores ambientales que varían con la elevación, esperábamos encontrar cambios en los rasgos de la biología reproductiva de Z. capensis a diferentes elevaciones. En este estudio, comparamos la biología reproductiva (tamaño de puesta, volumen del huevo y actividad reproductiva) de una población no migratoria de Z. capensis en dos localidades a diferente elevación (elevación baja 1 800 m snm, y elevación alta 3 800 m snm,) y a la misma latitud en los Andes tropicales colombianos por un período de un año. No encontramos diferencias en el tamaño de puesta entre las localidades; sin embargo, el volumen del huevo fue mayor en elevación alta. Además, la actividad reproductiva difirió entre las localidades. Proponemos que el tamaño de puesta probablemente se conserve en toda la distribución altitudinal de Z. capensis, ya que la especie evolucionó en las tierras bajas tropicales. Por otro lado, el mayor volumen del huevo a elevación alta podría obedecer a factores ambientales locales que pueden favorecer el éxito reproductivo de la población.

13.
Biota Neotrop. (Online, Ed. ingl.) ; 20(2): e20190867, 2020. graf
Artigo em Inglês | LILACS-Express | LILACS | ID: biblio-1089120

RESUMO

Abstract Populations that breed along steep elevation gradients show diverse physiological and morphological changes in response to the different environmental conditions. The latter has been discussed by Bergmann's and Allen's ecogeographic rules about body and appendage sizes and environmental temperature. We compared morphometric measures (mass, bill width, tarsus, wing, and tail length) of a Zonotrichia capensis population in two localities at different elevations with similar latitudes and photoperiods on the western slope of the Colombian Central Andes. We compared a Low Elevation locality (LE) at 1800 m a.s.l. and a High Elevation locality (HE) at 3853 m a.s.l. that have approximate wind speeds of 1.3 m/s and 8.4 m/s, respectively. During 12 months of sampling, we captured 46 adults using mist-nets; 26 in the LE and 20 in the HE. Each individual was sexed using molecular techniques at the Laboratory of Genetics of the Department of Biological Sciences of Universidad de Caldas. Individuals (males + females) from the HE had longer wings and tails than those from the LE (F1,44 = 5.93; P = 0.019). Also, wings of males in the HE were longer than those of females in both localities and tails of males in the HE were longer than those of LE males. Our results did not agree with what was expected according to Allen's and Bergmann's ecogeographic rules. Longer wings and tails increase sustainment, maneuverability, and balance in low atmospheric pressures and strong air currents and these conditions are found at high elevation habitats. Most likely, the longer wings found for HE males allow greater movement during territorial behavior. Further, these differences in morphological traits along elevational gradients could result from micro-evolutionary changes between localities or phenotypic plasticity of individuals exposed to different environmental conditions.


Resumen Las poblaciones que se reproducen en gradientes altitudinales, adoptan diversos cambios morfológicos para afrontar las condiciones ambientales. En el presente estudio se compararon las medidas morfológicas (peso corporal, longitud del tarso, ala, cola y culmen) de una población de Zonotrichia capensis, a diferente altitud en los Andes colombianos. Las localidades de tierra baja (TB) y alta (TA) se encuentran a 1800 m.s.n.m. y 3853 m.s.n.m., con velocidad aproximada del viento de 1.3 m/s y 8.4 m/s, respectivamente. Durante 12 meses se realizó la captura de 46 individuos (TB n=26, TA n=20) para la medición de los rasgos morfológicos. La longitud del ala de los individuos de TA fue mayor que en TB. Así mismo, en machos de TA la longitud del ala fue mayor que en hembras en general. Es posible que a las más grandes incrementen la eficiencia del vuelo en zonas ventosas y con baja presión atmosférica, como ocurre en TA. Probablemente la diferencia del tamaño del ala entre los machos de TA y las hembras, se deba a un mayor desplazamiento dentro de la conducta territorial. Estas diferencias podrían ser el resultado de cambios microevolutivos entre localidades o la plasticidad fenotípica de individuos expuestos a diferentes condiciones ambientales.

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