coat color and biochemical variation in amazonian wild populations of alouatta belzebul.a comparative study of 13 blood genetic systems and pelage color variation was performed in four wild populations of alouatta belzebul. the animals from the west bank of the tocantins river showed less color variation than those from the east bank, as well as less than those from tocantins island. the blood genetic markers, however, revealed an opposite pattern of variation. a previously undescribed morphological variant (completely red) was observed in one specimen of the east bank, where pelag ...19911853946
[natural infection of monkeys, alouatta belzebul belzebul (l., 1766), with plasmodium brazilianum gonder and berenberg-gossler, 1908, in the state of maranhão, brazil]. 19704989765
in situ hybridization (fish) maps chromosomal homologies between alouatta belzebul (platyrrhini, cebidae) and other primates and reveals extensive interchromosomal rearrangements between howler monkey genomes.we hybridized whole human chromosome specific probes to metaphases of the black-and-red howler monkey alouatta belzebul in order to establish chromosomal homology between humans and black-and-red howlers. the results show that the black-and-red howler monkey has a highly rearranged genome and that the human chromosome homologs are often fragmented and translocated. the number of hybridization signals we obtained per haploid set was 40. nine human chromosome probes gave multiple signals on differ ...19989773675
fluorescence in situ hybridization (fish) maps chromosomal homologies between the dusky titi and squirrel monkey.the platyrrhini are one of the most karyologically derived groups of primates and the evolution of their karyotypes is far from understood. the identification of the origin and direction of chromosome rearrangements will contribute to a better understanding of new world monkey phylogeny, taxonomy, and evolution. we mapped homology and identified translocations in the chromosomes of the dusky titi monkey (callicebus moloch, 2n = 50) and the squirrel monkey (saimiri sciureus, 2n = 44) by fluoresce ...200010676707
habitat use by chiropotes satanas utahicki and syntopic platyrrhines in eastern amazonia.primates were surveyed at two sites in the xingu-tocantins interfluvium, in eastern amazonia, where at least eight platyrrhines are known to occur, including the endemic chiropotes satanas utahicki, vulnerable to extinction. only three other forms; alouatta belzebul belzebul, cebus apella apella, and saguinus midas niger; were recorded at both sites. data on habitat use (forest type and strata) were collected in standard line transect surveys and analyzed with relation to the availability of for ...200010711535
molecular phylogenetics of howler monkeys (alouatta, platyrrhini). a comparison with karyotypic data.molecular phylogenetic analyses of seven brazilian alouatta species, based on cytochrome b dna sequence data were carried out. parsimony and neighbor joining topologies grouped alouatta belzebul and a. fusca as sister groups in one clade while another, well-supported clade contained a. seniculus as the most basal offshoot, followed by a. nigerrima as a sister lineage of a. macconnelli/a. stramineus. estimates of inter-specific sequence divergence were generally low, and estimates of the time of ...200111513299
geophagy as a correlate of folivory in red-handed howler monkeys (alouatta belzebul) from eastern brazilian amazonia.howler monkeys, alouatta spp., are the most folivorous of neotropical primates (platyrrhini), although amazonian red-handed howlers (alouatta belzebul) are relatively frugivorous. the feeding ecology of a free-ranging group of a. belzebul was monitored at a site in eastern brazilian amazonia over a tenmonth period (november 1997 to august 1998). the first half of the study period encompassed the peak of the wet season, during which the study group's diet was predominantly frugivorous (scan sampl ...200212371813
molecular systematics and biogeography of the neotropical monkey genus, alouatta.we take advantage of the broad distribution of howler monkeys from mexico to argentina to provide a historical biogeographical analysis on a regional scale that encompasses the entire neotropics. the phylogenetic relationships among 9 of the 10 recognized alouatta species were inferred using three mitochondrial and two nuclear genes. the nuclear gene regions provided no phylogenetic resolution among howler monkey species, and were characterized by very low levels of sequence divergence between a ...200312470939
interactions between tayras (eira barbara) and red-handed howlers (alouatta belzebul) in eastern amazonia.two tayras (eira barbara) were observed attacking an infant red-handed howler (alouatta belzebul) on an island in eastern brazilian amazonia, as a nearby adult male watched passively. in a separate incident, four tayras were seen attacking a subadult female on the ground. tayras were also observed in the vicinity of the two howler study groups on a number of occasions over a 9-month period. during this same period, the two groups lost a third of their members, including infants and subadults, an ...200716944250
observations of daytime births in two groups of red-handed howlers (alouatta belzebul) on an island in the tucuruí reservoir in eastern brazilian amazonia.births were observed in two free-ranging groups of red-handed howlers (alouatta belzebul) in eastern brazilian amazonia. both events occurred in the early afternoon, and were relatively rapid and discrete. no other group members approached the females during parturition, nor attempted to interfere with the neonate in any way. only one of the mothers ingested the placenta. this same female carried the neonate ventrally during the first month of life and then it was carried dorsally. the other inf ...200717427977
geophagy in new world monkeys (platyrrhini): ecological and geographic patterns.geophagy has been recorded in an increasing number of new world monkeys (platyrrhini) over recent years, permitting a tentative analysis of ecological patterns. while geophagy has now been recorded in species representing all 4 platyrrhine families and a majority of genera, there is a marked tendency for it to occur in the larger-bodied pitheciidae and atelidae. howlers (alouatta) are responsible for almost a third of reports, which are concentrated in the more frugivorous species, alouatta belz ...200818587239
isolation and genetic characterisation of toxoplasma gondii from a red-handed howler monkey (alouatta belzebul), a jaguarundi (puma yagouaroundi), and a black-eared opossum (didelphis aurita) from brazil.toxoplasma gondii isolates are highly diverse in domestic animals from brazil. however, little is known about the genetics of this parasite from wild mammals in the same region. reveal genetic similarity or difference of t. gondii among different animal populations is necessary for us to understand transmission of this parasite. here we reported isolation and genetic characterisation of three t. gondii isolates from wild animals in brazil. the parasite was isolated by bioassay in mice from tissu ...201021055880
genetic structure of red-handed howler monkey populations in the fragmented landscape of eastern brazilian amazonia.we genotyped 15 microsatellite loci in order to evaluate the effects of habitat fragmentation, caused by flooding of the tucuruí reservoir, on the genetic structure of alouatta belzebul in eastern amazonia. the analysis included two populations sampled in 1984, representing both margins of the tocantins river, and three populations sampled 18 years later. minimal differences in the diversity levels between present-day (ho = 0.62-0.69 and a(r) = 6.07-7.21) and pre-flooding (ho = 0.60-0.62 and a ( ...201021637590
polyspecific associations between squirrel monkeys (saimiri sciureus) and other primates in eastern of the most common types of polyspecific association observed in neotropical primate communities is that between squirrel monkeys (saimiri) and capuchins (cebus). the present study focused on association patterns in two saimiri sciureus groups in eastern brazilian amazonia, between march and october, 2009. the associations were analyzed in terms of the species involved, the degree of association, and niche breadth and overlap. the study involved two s. sciureus groups (b4 and gi) on the righ ...201121809365
lineage-specific serology confirms brazilian atlantic forest lion tamarins, leontopithecus chrysomelas and leontopithecus rosalia, as reservoir hosts of trypanosoma cruzi ii (tcii).trypanosoma cruzi, the agent of chagas disease in humans, has a vast reservoir of mammalian hosts in the americas, and is classified into six genetic lineages, tci-tcvi, with a possible seventh, tcbat. elucidating enzootic cycles of the different lineages is important for understanding the ecology of this parasite, the emergence of new outbreaks of chagas disease and for guiding control strategies. direct lineage identification by genotyping is hampered by limitations of parasite isolation and c ...201627846858
local ecological knowledge about endangered primates in a rural community in paraíba, brazil.the study of local ecological knowledge (lek) fosters a better understanding of the relationship between humans and the environment. we assessed respondents' ecological knowledge of primates in a rural community located near the atlantic forest remnants in the state of paraíba, brazil. populations of alouatta belzebul (red-handed howler monkeys), sapajus flavius (blonde capuchins), and callithrix jacchus (the common marmoset) inhabit the region. we conducted 200 semi-structured interviews and ap ...201627866209
environmental perturbations can be detected through microwear texture analysis in two platyrrhine species from brazilian amazonia.recent dental microwear studies have shown that fossil species differ from one another in texture attributes-both in terms of central tendency and dispersion. most comparative studies used to interpret these results have relied on poorly provenienced museum samples that are not well-suited to consideration of within species variation in diet. here we present a study of two species of platyrrhine monkeys, alouatta belzebul (n = 60) and sapajus apella (n = 28) from pará state in the brazilian amaz ...201526348252
evaluation of the fecal steroid concentrations in alouatta belzebul (primates, atelidae) in the national forest of tapirape-aquiri in pará, brazil.the studies on fecal steroid metabolites published with free-living primates are limited mainly by the difficulty in obtaining samples.201323909605
identification of bacterial infection in neotropical primates.emerging infectious diseases usually arise from wild animal populations. in the present work, we performed a screening for bacterial infection in natural populations of new world primates. the blood cell bulk dnas from 181 individuals of four platyrrhini genera were pcr screened for eubacterial 16s rrna genes. bacteria were detected and identified in 13 distinct individuals of alouatta belzebul, alouatta caraya, and cebus apella monkeys from geographically distant regions in the states of mato g ...201323797292
population genetic studies of alouatta belzebul from the amazonian and atlantic forests.cytochrome b dna sequence data (ca. 1,140 bp) of 66 alouatta belzebul from the amazonian and the atlantic forests of brazil were used for phylogenetic reconstructions and population studies. our sample consisted of 60 specimens from the amazonian forest (captured in 1984 and 1998 in pará-pa state) and six specimens from the atlantic forest (paraíba-pb state). we found 32 haplotypes, 23 in pa-1984 (with 12 present in more than one individual), 11 in pa-1998 (with two present in more than one indi ...200818080315
cytochrome b polymorphisms and population structure of two species of alouatta (primates).we carried out a phylogenetic and population study in alouatta caraya and alouatta belzebul based on cytochrome b dna sequence data. maximum parsimony and median-joining analyses grouped a. caraya from different localities showing a population structure in accordance with geographic distribution. the relation between a. caraya haplotypes could be explained with respect to the species range in the cerrado, one of the most ancient morphoclimatic domains of south america, and the chaco. conversely, ...200515545722
cytogenetic characterization of alouatta belzebul with atypical pelage coloration. 19892807099
anatomy of the dura mater venous sinus of alouatta belzebul.the anatomy of the dura mater's venous sinuses is important in the veterinary clinical and surgical area, for cranial procedures and interventions of wild animals, in addition to assisting in the management of neurological diseases, which can prevent serious complications. the macroscopic anatomy of the venous sinuses of the dura mater of alouatta belzebul was studied. five adult specimens, males and females, were dissected and fixed in 10% formaldehyde solution. in the dura mater of the alouatt ...202032738181
evolution of the human chromosome 13 synteny: evolutionary rearrangements, plasticity, human disease genes and cancer breakpoints.the history of each human chromosome can be studied through comparative cytogenetic approaches in mammals which permit the identification of human chromosomal homologies and rearrangements between species. comparative banding, chromosome painting, bacterial artificial chromosome (bac) mapping and genome data permit researchers to formulate hypotheses about ancestral chromosome forms. human chromosome 13 has been previously shown to be conserved as a single syntenic element in the ancestral prima ...202032244767
molecular phylogenetic inference of the howler monkey radiation (primates: alouatta).howler monkeys (alouatta), comprising between nine and 14 species and ranging from southern mexico to northern argentina, are the most widely distributed platyrrhines. previous phylogenetic studies of howlers have used chromosomal and morphological characters and a limited number of molecular markers; however, branching patterns conflict between studies or remain unresolved. we performed a new phylogenetic analysis of alouatta using both concatenated and coalescent-based species tree approaches ...202032876810
the occurrence of the red-handed howler monkey (alouatta belzebul) in amazonian savannas is related to forest patch area and density of flooded area palms.all neotropical primates are arboreal and thus depend on forests for their survival. arboreality puts many neotropical primates at risk of extinction due to the high rates of deforestation in the tropics. we assessed the influence of vegetation structure and forest patch attributes on the occurrence of the threatened red-handed howler monkey (alouatta belzebul) in an amazonian savanna. using a sample of 38 forest patches in a region of approximately 2000 km2 in the state of amapá, northern brazi ...202033124052
chromosome studies in alouatta belzebul.the chromosome constitution of alouatta belzebul was studied with g-, c-, and silver staining. in ten specimens identified as alouatta belzebul, the chromosome constitution of males (2n = 49) differed from that of females (2n = 50) owing to a y-autosome translocation. in another single female specimen, probably alouatta belzebul nigerrima, the diploid chromosome number was also 50, though its karyotype was drastically different from that of alouatta belzebul belzebul. chromosome studies, taken t ...198731973466
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