| blood groups of the mantled howler monkey (alouatta palliata). | fifty-two howler monkeys were tested for their human-type a-b-o blood groups. all were group b, as shown by the presence of b and h in their saliva, and anti-a in serum. the b-like agglutinogen of their red cells is common to all new world monkey species tested, and is of different origin and significance than their true a-b-o blood group. differences among the b-like agglutinogens of the red cells of howler monkeys, marmosets, rabbits and humans group b were demonstrated, and limited tests have ... | 1977 | 412971 |
| drinking from arboreal water sources by mantled howling monkeys (alouatta palliata gray). | despite occasional trips to the ground and feeding in trees whose canopies touched the river, mantled howling monkeys were never seen to drink from any ground water. drinking from arboreal cisterns was observed, but only during the wet season (meteorologically the less stressful season but phenologically the more stressful season). the lack of sufficient new leaves during the wet season forced the howlers to ingest more mature leaves which contained significantly less water. to compensate for th ... | 1978 | 417985 |
| urine-rubbing behavior in the mantled howler monkey alouatta palliata. | mantled howler monkeys (alouatta palliata) of both sexes and all age classes were observed rubbing urine on the soles of the feet and/or palms of the hands as well as the ventral surface of the tail and, occasionally, the throat. instances of urine-rubbing were often associated with periods of troop movement or times of social stress. intra-troop cohesion may be the primary function of such behavior. other possible function of urine-rubbing are discussed. | 1975 | 806506 |
| y-autosome translocation in the howler monkey, alouatta palliata. | two modal diploid chromosome numbers were encountered in a population sample of howler monkeys, alouatta palliata. the modal diploid number of males was 53, females: 54. karyotypes prepared by g-band and c-band techniques identified a y-auto-some translocation in the males. | 1975 | 810590 |
| vocalizations of howler monkeys (alouatta palliata) in southwestern panama. | this report presents an analysis of the vocal repertoire of howler monkeys (alouatta palliata) observed during a field study in southwestern panama. 26 types of vocalizations were identified and described, and sonagrams are presented for 21 of them. the vocal repertoire contained many nondiscrete calls that graded continuously into each other, and all of the calls appeared to fit into 5 or 6 broad families. a tape recording of the vocalizations described in this study is available. | 1976 | 821833 |
| experiments of nature: premature unicoronal cranial synostosis in mantled howler monkeys (alouatta palliata). | in 1960 adolph schultz described several cases of plagiocephaly in a collection of mantled howler monkeys (alouatta palliata) from the forests of central america. since then several more specimens have been described. these individuals make up one of the largest samples of nonhuman primates that are affected by craniosynostosis. in this study, we used finite element scaling analysis (fesa) to quantify morphologic differences between adult normal (n = 19) and plagiocephalic female howler monkeys ... | 1992 | 1571347 |
| field methods for capture and measurement of three monkey species in costa rica. | a total of 54 free-ranging monkeys were captured and marked in santa rosa national park, costa rica, during may 1985, and an additional 17 were captured during march 1986. the animals were darted using a blowpipe or a co2 gun. the drugs used were ketaset, sernylan and telazol. ketaset was effective for cebus capucinus but unsuccessful for alouatta palliata and ateles geoffroyi. sernylan was successful for a. geoffroyi and a. palliata but is no longer commercially available. telazol proved to be ... | 1991 | 1786909 |
| dental microwear in live, wild-trapped alouatta palliata from costa rica. | one problem with dental microwear analyses of museum material is that investigators can never be sure of the diets of the animals in question. an obvious solution to this problem is to work with live animals. recent work with laboratory primates has shown that high resolution dental impressions can be obtained from live animals. the purpose of this study was to use similar methods to begin to document rates and patterns of dental microwear for primates in the wild. thirty-three alouatta palliata ... | 1991 | 1897604 |
| a coprological survey of parasites of wild mantled howling monkeys, alouatta palliata palliata. | fecal samples from 155 mantled howling monkeys (alouatta palliata palliata) examined at centro ecologico la pacifica, guanacaste province, costa rica, revealed 75 (48%) had parasitic infections. a sampling of nine howling monkeys from santa rosa national park. costa rica indicated only one infected animal (11%). only three of 19 (16%) spider monkeys (ateles geoffroyi) also from santa rosa were infected. controrchis biliophilus, trypanoxyuris minutus, unidentified strongylid eggs and isospora sp. ... | 1990 | 2250334 |
| behavioral development and socialization of infants in a free-ranging group of howling monkeys (alouatta palliata). | a 22-month field study was carried out on free-ranging mantled howlers in costa rica. six female and 5 male infants were observed systematically from birth until they died, left the group, or the study ended. interaction patterns, activity patterns, and proximity data were analyzed from 703 h of focal observations and 753 h of ad lib observations. developmental trends in weaning and nonmother care were associated with mothers' feeding patterns, suggesting an increase in maternal feeding efficien ... | 1990 | 2323684 |
| ecological constraints on group size in three species of neotropical primates. | the foraging strategies and association patterns of 3 species of primates (ateles geoffroyi, alouatta palliata, cebus capucinus) were studied over a 5-year period. the objective of the study was to provide a quantitative test of the hypothesis that the size, density and distribution of food resources influence the size of animal groups. in examining the assumptions of this hypothesis, it was shown that these primates used resources that occurred in patches, depleted the patches through their use ... | 1990 | 2394411 |
| plasma lipoproteins of free-ranging howling monkeys (alouatta palliata). | 1. plasma lipids and lipoproteins of free-ranging howling monkeys from costa rica (alouatta palliata), aged 5 months to 23 years, were characterized. 2. high density lipoproteins were lipid-rich, similar to hdl2 of human plasma. 3. fatty acid compositions of major lipid classes of very low, low and high density lipoproteins differed among social groups, possibly due to both dietary and genetic factors. 4. low and high density lipoprotein phospholipids were enriched in phosphatidylethanolamine. 5 ... | 1987 | 3427910 |
| interactions between adult female and infant howling monkeys (alouatta palliata). | | 1973 | 4204889 |
| rates of fermentative digestion in the howler monkey, alouatta palliata (primates: ceboidea). | 1. caecal material of wild howler monkeys was analyzed by gas chromatography for evidence of fermentation activity and rates of production and absorption of volatile fatty acids. 2. results showed a high rate of production of acetic acid and lesser production of propionic, butyric and isobutyric acids. the vfa content of the blood was increase in passage through the caecal vascular system. 3. we estimate that howler monkeys may obtain as much as 31% of their required daily energy from fermentati ... | 1983 | 6130881 |
| reproduction and population growth in free-ranging mantled howling monkeys. | free-ranging mantled howling monkey (alouatta palliata gray) females experienced a regular estrus cycle averaging 16.3 days, demonstrated sexual skin changes, and participated in multiple matings before becoming pregnant. gestation averaged 186 days. the average interval between births was 22.5 months. sexual maturity occurred at approximately 36 and 42 months for females and males, respectively. female age at first birth was about 3 1/2 years. births were scattered during some years and cluster ... | 1980 | 7416246 |
| comparative and functional myology of the prehensile tail in new world monkeys. | the caudal myology of prehensile-tailed monkeys (cebus apella, alouatta palliata, alouatta seniculus, lagothrix lagotricha, and ateles paniscus) and nonprehensile-tailed primates (eulemur fulvus, aotus trivirgatus, callithrix jacchus, pithecia pithecia, saimiri sciureus, macaca fascicularis, and cercopithecus aethiops) was examined and compared in order to identify muscular differences that correlate with osteological features diagnostic of tail prehensility. in addition, electrophysiological st ... | 1995 | 7595958 |
| play as physical flexibility training in five ceboid primates. | instantaneous focal animal sampling of positional behavior (posture and locomotion) during the play and nonplay of adults and juveniles of 5 ceboid monkeys (alouatta palliata, ateles geoffroyi, cacajao calvus, cebus capucinus, and saimiri boliviensis) in an optimal design field study of the function of play as physical flexibility training produced a sample of 98,261 observations. analyses of 67 distinct modes of positional behavior demonstrated that significantly enhanced rates of suspension an ... | 1994 | 7924251 |
| fatty acid profiles of major food sources of howler monkeys (alouatta palliata) in the neotropics. | wild howler monkeys (alouatta palliata) get most of their calories from carbohydrates (65%) and fats (18%) of native tropical plants, but little is known about their intake of individual fatty acids. the fatty acid composition of several natural food sources of howler monkeys collected in panama was determined by gas-liquid chromatography. the predominant fatty acids were palmitic (30%), linoleic (23%), alpha-linolenic (16%) and oleic (15%). fatty acids with less than 16, and more than 18, carbo ... | 1993 | 8104821 |
| antibody immunoglobulin g (igg) response to alouattamyia baeri (diptera:cuterebridae) parasitism of howler monkeys, alouatta palliata, in panama. | larval bot fly burdens and the presence of immunoglobulin g (igg) antibodies to larval antigens of alouattamyia baeri (shannon & greene) were determined in howler monkeys, alouatta palliata authority, from barro colorado island, panama, during july and august of 1991 and 1992. monkeys produced antibodies (igg) to both 1st- and 3rd-instar proteins of the monkey bot as measured by an enzyme immunoassay. the response to 1st-instar antigen was correlated with number of bots for the 1991 data and for ... | 1996 | 8961644 |
| stable isotope ratios indicate diet and habitat use in new world monkeys. | this paper demonstrates the use of stable isotope ratios of carbon and nitrogen in animal tissue for indicating aspects of species behavioral strategy. we analyzed hair from individuals representing four species of new world monkeys (alouatta palliata, the mantled howler; ateles geoffroyi, the spider monkey; cebus capucinus, the capuchin; and brachyteles arachnoides, the woolly-spider monkey or muriqui) for delta 13c and delta 15n using previously developed methods. there are no significant diff ... | 1997 | 9185952 |
| conspecific aggression and predation: costs for a solitary mantled howler monkey. | | 1997 | 9212460 |
| characterization of microsatellite loci in a new world primate, the mantled howler monkey (alouatta palliata). | | 1998 | 9633106 |
| development of alouattamyia baeri (diptera: oestridae) from howler monkeys (primates: cebidae) on barro colorado island, panama. | the fecundity and development of larval stages of the cuterebrid bot fly a. baeri were studied in an unusual host, remotely related to the primary host. third-instar alouattamyia baeri (shannon & greene) removed from howler monkeys, alouatta palliata, were allowed to pupate and then were cultured under controlled conditions. eclosion occurred after 37.9 +/- 0.4 (mean +/- se) (male) and 38.2 +/- 0.4 (female) d at 26 degrees c. five-day-old females were mated using a tethered flight technique and ... | 1998 | 9775591 |
| feeding and general activity patterns of a howler monkey (alouatta palliata) troop living in a forest fragment at los tuxtlas, mexico. | the feeding behavior and general activity patterns of a howler monkey troop living in a 3.6 ha forest fragment were studied at los tuxtlas, mexico, for an annual cycle. monthly samples of their feeding behavior indicated that they used 52 species of 24 plant families as sources of food. of these, 67% were trees, which accounted for 96% of total feeding time recorded. ten species of moraceae, cecropiaceae, anacrdiaceae. and sapotaceae contributed to 70% of the trees used and to almost 90% of feed ... | 1999 | 10380993 |
| tropical rain forest fragmentation, howler monkeys (alouatta palliata), and dung beetles at los tuxtlas, mexico. | in neotropical rain forests, fresh mammal dung, especially that of howler monkeys, constitutes an important resource used by dung beetles as food and for oviposition and further feeding by their larvae. tropical rain forest destruction, fragmentation, and subsequent isolation causing reductions in numbers of and the disappearance of howler monkeys may result in decreasing numbers of dung beetles, but this has not been documented. in this study, we present information on the presence of howlers a ... | 1999 | 10402034 |
| craniometric variation in a population of mantled howler monkeys (alouatta palliata): evidence of size selection in females and growth in dentally mature males. | a large body of work on monkey cranial metrics (involving conclusions about interspecific variation, sexual dimorphism, and ontogeny) depends on the assumptions that growth effectively ceases with dental maturity and that intraspecific variation is negligible. we test these assumptions by examining variation in 39 measurements of 166 dentally mature alouatta palliata skulls from animals found dead on barro colorado island (bci), panama. we also investigate whether this population is under size-b ... | 2000 | 11042541 |
| congruence of tail use behaviors between male and female mantled howling monkeys (alouatta palliata). | | 2001 | 11805425 |
| mantled howler population of hacienda la pacifica, costa rica, between 1991 and 1998: effects of deforestation. | a survey of the mantled howler (alouatta palliata) population on hacienda la pacifica, guanacaste, costa rica, was done in july and august of 1998 to determine population parameters following deforestation due to major canal construction between 1990 and 1994. the survey was carried out in a manner identical to our 1991 survey and consisted of a single pass and two re-surveys of all forested areas of the farm. as canal construction effectively increased fragmentation of the habitat, we predicted ... | 2002 | 11857652 |
| interspecific interaction and predator avoidance behavior in response to tayra (eira barbara) by mantled howler monkeys (alouatta palliata). | this paper reports the response of one howler monkey group (alouatta palliata) to a group of potential predators, the tayra (eira barbara). the apparently successful predator avoidance behavior of the monkeys was recorded in detail. we observed a group of four adult tayras moving around the alouatta group displaying a species-typical aggressive behavioral pattern. the two adult females of the howler group successfully chased the tayras away by repeatedly moving closer to the mustelids and even f ... | 2002 | 12426467 |
| 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 ... | 2003 | 12470939 |
| rapid acquisition of an alarm response by a neotropical primate to a newly introduced avian predator. | predation is an important selective pressure in natural ecosystems. among non-human primates, relatively little is known about how predators hunt primate prey and how primates acquire adaptive responses to counteract predation. in this study we took advantage of the recent reintroduction of radio-tagged harpy eagles (harpia harpyja) to barro colorado island (bci), panama to explore how mantled howler monkeys (alouatta palliata), one of their primary prey, acquire anti-predator defences. based on ... | 2003 | 12769460 |
| natural selection on molar size in a wild population of howler monkeys (alouatta palliata). | dental traits have long been assumed to be under selection in mammals, based on the macroevolutionary correlation between dental morphology and feeding behaviour. however, natural selection acting on dental morphology has rarely, if ever, been documented in wild populations. we investigated the possibility of microevolutionary selection on dental traits by measuring molar breadth in a sample of alouatta palliata (mantled howler monkey) crania from barro colorado island (bci), panama. the age at ... | 2003 | 12952624 |
| the vocal organ of the howling monkey (alouatta palliata). | | 1960 | 13752246 |
| group size in folivorous primates: ecological constraints and the possible influence of social factors. | the ecological-constraints model assumes that food items occur in depletable patches and proposes that an increase in group size leads to increased day range due to more rapid patch depletion. smaller groups become advantageous when an increase in travel costs is not repaid by an increase in energy gained or some other fitness advantage. on the other hand, we also know that group size can be influenced by social factors. here we contrast the diet and group size of red colobus (procolobus badius) ... | 2005 | 15197599 |
| dental topography and molar wear in alouatta palliata from costa rica. | paleoprimatologists depend on relationships between form and function of teeth to reconstruct the diets of fossil species. most of this work has been limited to studies of unworn teeth. a new approach, dental topographic analysis, allows the characterization and comparison of worn primate teeth. variably worn museum specimens have been used to construct species-specific wear sequences so that measurements can be compared by wear stage among taxa with known differences in diet. this assumes that ... | 2004 | 15365981 |
| observation of parturition in the mexican mantled howler monkeys (alouatta palliata) on the island of agaltepec, veracruz state, mexico. | we observed a birth in a group of mexican mantled howler monkeys (alouatta palliata) living under semi-free-ranging conditions on agaltepec island, catemaco, veracruz, mexico. although we could not quantify contractions, we were able to record a complete description of the sequence of events that resulted in a successful birth. nine minutes passed from the release of the amniotic fluid to the total emergence of the infant. although all group members were resting relatively close to the female wh ... | 2005 | 15645458 |
| seismic activity response as observed in mantled howlers (alouatta palliata), cuero y salado wildlife refuge, honduras. | this report documents the response of wild mantled howlers (alouatta palliata) to coseismic activity (seismic activity at the time of an earthquake). during field work on the north coast of honduras, data were collected on a habituated troop of mantled howlers as they responded to coseismic activity. the seismic event occurred on 13 february 2001 at 0822 hours local time with a magnitude of richter scale 6.6, focus depth of approximately 15 km at a distance of 341 km from the epicentre to the fi ... | 2005 | 16091980 |
| mechanical defenses in leaves eaten by costa rican howling monkeys (alouatta palliata). | primate species often eat foods of different physical properties. this may have implications for tooth structure and wear in those species. the purpose of this study was to examine the mechanical defenses of leaves eaten by alouatta palliata from different social groups at hacienda la pacifica in costa rica. leaves were sampled from the home-ranges of groups living in different microhabitats. specimens were collected during the wet and dry seasons from the same tree, same plant part, and same de ... | 2006 | 16136580 |
| testosterone levels of free-ranging resident mantled howler monkey males in relation to the number and density of solitary males: a test of the challenge hypothesis. | the challenge hypothesis asserts that testosterone levels and aggression in male adult animals are closely associated with one another in the context of intense reproductive competition, particularly when males challenge one another for the access to females. for mantled howler monkeys (alouatta palliata), the presence of a solitary male in the vicinity of a social group can be considered a threat for the reproductive success of the resident males, as group takeovers by solitary males are follow ... | 2006 | 16182297 |
| biogeographical and floristic predictors of the presence and abundance of mantled howlers (alouatta palliata mexicana) in rainforest fragments at los tuxtlas, mexico. | this research focuses on identifying the principal habitat characteristics that influence the presence and abundance of mantled howlers in forest fragments. we provide information on the demography of several fragmented alouatta palliata mexicana subpopulations at los tuxtlas, mexico, and relate this to the biogeographical and floristic characteristics of the forest fragments inhabited. the most important habitat characteristics related to the presence and abundance of howlers in the fragments w ... | 2005 | 16229005 |
| possible costs of radio-tracking a young adult female mantled howler monkey (alouatta palliata) in deciduous habitat of costa rican tropical dry forest. | | 2005 | 16468950 |
| functional morphology of the first cervical vertebra in humans and nonhuman primates. | the cervical vertebral column bears or balances the weight of the head supported by the nuchal muscles that partly originate from the cervical vertebrae. the position of the head relative to the vertebral column, and consequently locomotion and posture behavior, could thus be associated with the form of the cervical vertebrae. in spite of this assumption and some empirical indications along these lines, primate vertebral morphologies have been reported to be very similar and not clearly related ... | 2006 | 16955497 |
| behavior and endocrine concentrations do not distinguish sex in monomorphic juvenile howlers (alouatta palliata). | behavioral observations on juvenile mantled howlers are limited by visually undifferentiated genitalia; however, animals can be sexed when they are very young or if they are captured. behavioral data and fecal samples from juveniles during month-long field studies from 1993 to 1995 were analyzed to determine whether there are developmental differences in behavior or hormone concentrations that can be used to differentiate males from females. the subjects were juveniles of known sex and age from ... | 2007 | 17154381 |
| exploring immature-to-mother social distances in mexican mantled howler monkeys at los tuxtlas, mexico. | we analyzed immature-to-mother social distance (juveniles and non-nursing infants) in two mexican mantled howler monkey (alouatta palliata) troops inhabiting a tropical rainforest fragment (40 ha) at los tuxtlas, veracruz, mexico. during july and august of 2000 and 2001 we applied an instantaneous sampling method (317 hr) to record the behaviors of the immatures and their mothers, as well as distances (ordinal scale) between immatures and their mothers (imd), and between immatures and nonmother ... | 2007 | 17154388 |
| diet and activity pattern of howler monkeys (alouatta palliata) in los tuxtlas, mexico: effects of habitat fragmentation and implications for conservation. | accelerated deforestation is causing the rapid loss and fragmentation of primary habitat for primates. although the genus alouatta is one of the most studied primate taxa under these circumstances, some results are contradictory and responses of howlers to habitat fragmentation are not yet clear. in this paper, we conduct a cross-study of the available researches on mantled howlers (alouatta palliata) in forest fragments in los tuxtlas, mexico, to (1) describe the diet and activity pattern of ho ... | 2007 | 17330311 |
| [intestinal parasites in howler monkeys alouatta palliata (primates: cebidae) of costa rica]. | fecal samples of 102 howler monkeys (alouatta palliata) from several sites of costa rica were studied for intestinal parasites. the zones studied were: central valley (san ramón, alajuela), central pacific (chomes and manuel antonio national park. puntarenas), north pacific (palo verde park and playa potrero, guanacaste). chira island in the nicoya gulf and caribean area (cahuita. limón). animals were anesthetized with dards containing telazol in order to collect the fecal material; some monkeys ... | 2005 | 17354453 |
| a phylogeny of howler monkeys (cebidae: alouatta) based on mitochondrial, chromosomal and morphological data. | the current taxonomic status of the species and subspecies belonging to the genus alouatta is addressed by combined phylogenetic analysis using morphological, kariotipyc and molecular data (mitochondrial genes cytocrome oxidase ii and cytochrome b). our result demonstrated that alouatta palliata is the most basal taxon for the genus in concordance with previous studies, as well as showing the validity of the taxon alouatta sara as a species. also our analysis shows that the sex chromosome has ev ... | 2004 | 17361560 |
| distribution, ecology, life history, genetic variation, and risk of extinction of nonhuman primates from costa rica. | we examined the association between geographic distribution, ecological traits, life history, genetic diversity, and risk of extinction in nonhuman primate species from costa rica. all of the current nonhuman primate species from costa rica are included in the study; spider monkeys (ateles geoffroyi), howling monkeys (alouatta palliata), capuchins (cebus capucinus), and squirrel monkeys (saimiri oerstedii). geographic distribution was characterized accessing existing databases. data on ecology a ... | 2004 | 17361561 |
| foraging habits of alouatta palliata mexicana in three forest fragments. | the activity patterns and diet of howler monkeys (alouatta palliata mexicana) were studied in 3 forest fragments in south-eastern mexico: playa escondida (pla), agaltepec island (aga) and arroyo liza (liz). intersite differences offered the opportunity to investigate the foraging adaptations of howler monkeys in response to population and habitat size. in the largest fragment (pla), the howlers' diet was based on high-quality items (fruit and young leaves). in aga, where the density of howlers w ... | 2007 | 17429208 |
| multimodal communication by male mantled howler monkeys (alouatta palliata) in sexual contexts: a descriptive analysis. | we analyzed continuously sampled focal and ad libitum data of male mantled howler monkeys (alouatta palliata) observed in random order. males resided in two groups in a costa rican tropical dry forest environment (riparian habitat group: 3 males, 15 females, 402 h observation; deciduous habitat group: 2 males, 8 females, 114 h observation). samples were limited to sexual contexts, in particular, the 60-min periods before and after each copulation observed within each group for each male. time sa ... | 2007 | 17429210 |
| feeding selectivity by mantled howler monkeys (alouatta palliata) in relation to leaf secondary chemistry in hymenaea courbaril. | this study is a quantitative examination of primate feeding selectivity in relation to secondary chemistry within a single plant species, hymenaea courbaril. it provides the first evidence that sesquiterpenes may act as feeding deterrents in mantled howler monkeys. a free-ranging group of mantled howler monkeys at the study site of sector santa rosa, area de conservacion guanacaste, costa rica were observed for the 2-month period of h. courbaril leaf flush in 1999. tree characteristic data and l ... | 2007 | 17435985 |
| the distributions of howling monkeys (alouatta pigra and a. palliata) in southeastern mexico and central america. | we compared the distributions of alouatta palliata and a. pigra in southeastern mexico and central america with geographic and ecological features to infer current barriers and ecological preferences. distribution data were obtained from museum specimen localities, study sites, historic records and field surveys and integrated into digital elevation and ecosystem maps using gis. a. pigra evidently occurs at a number of sites above 2,000 m, where temperatures can even drop below zero on some days ... | 2007 | 17534693 |
| landscape attributes affecting patch occupancy by howler monkeys (alouatta palliata mexicana) at los tuxtlas, mexico. | understanding how forest cover is related to patch attributes such as size, shape, and isolation, and how this influences the occurrence of a species in fragmented landscapes is an important question in landscape ecology and conservation biology. to study the effects of fragmentation on patch occupancy by the critically endangered mexican mantled howler monkey (alouatta palliata mexicana) in the los tuxtlas region of mexico, we selected three landscapes of ca. 5,000 ha, which differed in their r ... | 2008 | 17583580 |
| demography, life history and migrations in a mexican mantled howler group in a rainforest fragment. | this paper represents the results of a long-term study (1996-2003) on the demographic changes over time of a mexican mantled howler (alouatta palliata mexicana) group in a rainforest fragment (40 ha) in los tuxtlas, mexico, with a follow-up census 3 years later (2006). in addition to demographic and life history parameters, we describe six dispersal events. our results suggest that this group has been expanding during the study period, growing from six to 12 individuals, with an annual average i ... | 2008 | 17701996 |
| demographic survey of black howler monkey (alouatta pigra) in the lachuá eco-region in alta verapaz, guatemala. | guatemala harbors three species of primates (alouatta palliata, alouatta pigra and ateles geoffroyi), but the distribution and state of conservation of populations of these species are poorly documented. in the case of a. pigra, populations have been studied recently and documented in several sites in mexico and belize, and only in one site in guatemala (tikal national park). in this study, we report first-time population data for a. pigra existing in the lachuá eco-region in northwestern guatem ... | 2008 | 17823920 |
| patterns of subgrouping and spatial affiliation in a community of mantled howling monkeys (alouatta palliata). | studies of social affiliation and social spacing offer important insight into the dynamics of subgroup formation and social strategies in living primates. among the 11 species in the genus alouatta, mantled howlers (a. palliata) are the only species to consistently form large, stable social groups composed of several adult males and several adult females. in this study, we examine patterns of subgrouping, activity, and partner preferences in a troop of 26-29 wild mantled howling monkeys (includi ... | 2008 | 17894404 |
| fatty acid composition of wild anthropoid primate milks. | fatty acids in milk reflect the interplay between species-specific physiological mechanisms and maternal diet. anthropoid primates (apes, old and new world monkeys) vary in patterns of growth and development and dietary strategies. milk fatty acid profiles also are predicted to vary widely. this study investigates milk fatty acid composition of five wild anthropoids (alouatta palliata, callithrix jacchus, gorilla beringei beringei, leontopithecus rosalia, macaca sinica) to test the null hypothes ... | 2008 | 17916436 |
| traditional nutritional analyses of figs overestimates intake of most nutrient fractions: a study of ficus perforata consumed by howler monkeys (alouatta palliata mexicana). | there continue to remain uncertainty concerning the nutritional importance of figs (ficus spp.) in the primate diet. although studies have been performed on the nutritional analysis of fig pulp and seed fractions separately, there has not been an attempt to quantify the contribution of animal matter within figs. here we report nutritional values of figs (ficus perforata) (urostigma) consumed by a troop of howler monkeys (alouatta palliata mexicana). separate nutritional assays were performed on ... | 2008 | 18161827 |
| group size and composition influence male and female reproductive success in black howler monkeys (alouatta pigra). | it has been argued that grouping patterns might influence the reproductive performance of individuals. increasing group size results in greater travel costs and competition over depletable food resources, which could lead to reduced individual reproductive success. however, in groups with an increasing number of males, female reproductive success is predicted to augment because larger male groups might better protect immatures from infanticidal attacks. in contrast, male reproductive success is ... | 2008 | 18293377 |
| the functions of the "greeting ceremony" among male mantled howlers (alouatta palliata) on agaltepec island, mexico. | nonhuman primates use greeting behaviors as nonaggressive communicatory signals in multiple social contexts. adult male mantled howlers (alouatta palliata) perform a ritual greeting that has been associated with bond-strengthening functions. the aim of this study is to explore the greeting patterns of male howlers living on agaltepec island, mexico. specifically, we analyzed the relationships between greetings and several individual, relational, and contextual variables, such as the expression o ... | 2008 | 18322923 |
| predicted and verified distributions of ateles geoffroyi and alouatta palliata in oaxaca, mexico. | primate conservation requires a better knowledge of the distributions and statuses of populations in both large areas of habitat and in areas for which we currently have no information. we focused on spider monkeys (ateles geoffroyi) and howler monkeys (alouatta palliata) in the state of oaxaca, mexico. this mexican state has protected large tracts of forest, and has historical records for both primates, although very little is known about them. to update our knowledge of the distributions of th ... | 2008 | 18523840 |
| differences in diet and activity pattern between two groups of alouatta palliata associated with the availability of big trees and fruit of top food taxa. | the threat that forest fragmentation and habitat loss presents for several alouatta taxa requires us to determine the key elements that may promote the persistence of howler monkeys in forest fragments and to evaluate how changes in the availability of these elements may affect their future conservation prospects. in this study we analyzed the relationship between the availability of both big trees of top food taxa (bttft) (diameter at breast height>60) and fruit of top food taxa (frtft) in the ... | 2009 | 19434679 |
| life history and locomotion in cebus capucinus and alouatta palliata. | as an individual matures from birth to adulthood, many factors may influence the positional repertoire. the biological and behavioral changes that accompany a growing individual are expected to influence foraging strategy, social status and interaction, diet, predator avoidance strategies, and ultimately positional behavior as a behavioral link between anatomy and the environment. in this work, positional behavior is considered as an important feature of life history in juvenile and adult white- ... | 2009 | 19530076 |
| prevalence of fur mites (acari: atopomelidae) in non-human primates of costa rica. | parasites have been investigated for some new world primates; however, very little is known about ectoparasites and specifically fur mites. in this study, alouatta palliata, cebus capucinus, saimiri oerstedii, and ateles geoffroyi monkeys from different areas of costa rica were searched for fur mites. a total of 276 monkeys were evaluated, and 51 of them were positive for mites of the family atopomelidae. listrocarpus alouattae was identified on 22.3% of a. palliata; listrocarpus capucinus on 12 ... | 2009 | 19637712 |
| variations in the mechanical properties of alouatta palliata molar enamel. | teeth have provided insights into many topics including primate diet, paleobiology, and evolution, due to the fact that they are largely composed of inorganic materials and may remain intact long after an animal is deceased. previous studies have reported that the mechanical properties, chemistry, and microstructure of human enamel vary with location. this study uses nanoindentation to map out the mechanical properties of alouatta palliata molar enamel on an axial cross-section of an unworn perm ... | 2010 | 19672851 |
| folivory or fruit/seed predation for mesopithecus, an earliest colobine from the late miocene of eurasia? | here we compare dental microwear textures from specimens of the fossil genus mesopithecus (cercopithecidae, colobinae) from the late miocene of eastern europe with dental microwear textures from four extant primate species with known dietary differences. results indicate that the dental microwear textures of mesopithecus differ from those of extant leaf eaters alouatta palliata and trachypithecus cristatus and instead resemble more closely those of the occasional hard-object feeders cebus apella ... | 2009 | 19733899 |
| chromobacterium violaceum infection in a free-ranging howler monkey in costa rica. | chromobacterium violaceum is a gram-negative saprobe bacterium that is a rare opportunistic pathogen in mammals. there are numerous reports in humans including fatalities, but no record exists in free-ranging nonhuman primates. here we report an infection by c. violaceum in a wild adult male howler monkey (alouatta palliata) captured at ballena marine national park, in southwestern costa rica. the individual had severe skin lesions over its extremities; gross findings included multiple skin ulce ... | 2010 | 20090050 |
| gastrointestinal parasites of howler monkeys (alouatta palliata) inhabiting the fragmented landscape of the santa marta mountain range, veracruz, mexico. | in recent years populations of howler monkeys (alouatta palliata) in southeastern mexico have decreased substantially due to the transformation and loss of natural habitats. this is especially evident in the santa marta mountain range, veracruz, mexico where several studies have evaluated the impact of fragmentation on howler monkey populations in order to propose management programs for their conservation. the conditions generated by fragmentation likely change the rates of parasitic infection ... | 2010 | 20135692 |
| parasitic infections of three mexican howler monkey groups (alouatta palliata mexicana) living in forest fragments in mexico. | in order to better understand how patterns of parasitism in howler monkeys are affected by forest fragmentation, we carried out a 1 year survey of gastrointestinal parasites in fecal samples from three groups of mexican howler monkeys inhabiting different forest fragments in the los tuxtlas biosphere reserve, mexico. the study groups were chosen because the conditions in which they lived suggested a potentially negative gradient for parasite richness and a positive gradient for levels of parasit ... | 2010 | 20224913 |
| secondary transfer of adult mantled howlers (alouatta palliata) on hacienda la pacifica, costa rica: 1975-2009. | natal emigration by male and female mantled howlers (alouatta palliata), and subsequent immigration into breeding groups, is well documented for the free-ranging population on hacienda la pacifica, costa rica, but secondary transfer was considered rare (glander in int j primatol 3:415-436, 1992). population surveys in 1998 and 2006 caused us to question our assumptions and to re-evaluate our long-term data set from a post hoc perspective. we first identified all animals observed or captured as a ... | 2010 | 20339901 |
| preliminary evidence of accumulation of stress during translocation in mantled howlers. | translocation--an extensively used conservation tool--is a potentially stressful event, as animals are exposed to multiple stressors and cannot predict or control the changes in their environment. therefore, it may be expected that during a translocation program stress accumulates and social behavior changes. here, we present data from a translocation of four adult mantled howlers (alouatta palliata), which was conducted in southern veracruz (mexico). we found that stress (measured in fecal cort ... | 2010 | 20653006 |
| chemical characterization of oligosaccharides in the milk of six species of new and old world monkeys. | human and great ape milks contain a diverse array of milk oligosaccharides, but little is known about the milk oligosaccharides of other primates, and how they differ among taxa. neutral and acidic oligosaccharides were isolated from the milk of three species of old world or catarrhine monkeys (cercopithecidae: rhesus macaque (macaca mulatta), toque macaque (macaca sinica) and hamadryas baboon (papio hamadryas)) and three of new world or platyrrhine monkeys (cebidae: tufted capuchin (cebus apell ... | 2010 | 21127965 |
| potential distribution of mexican primates: modeling the ecological niche with the maximum entropy algorithm. | we developed a potential distribution model for the tropical rain forest species of primates of southern mexico: the black howler monkey (alouatta pigra), the mantled howler monkey (alouatta palliata), and the spider monkey (ateles geoffroyi). to do so, we applied the maximum entropy algorithm from the ecological niche modeling program maxent. for each species, we used occurrence records from scientific collections, and published and unpublished sources, and we also used the 19 environmental cov ... | 2011 | 21404094 |
| does home range use explain the relationship between group size and parasitism? a test with two sympatric species of howler monkeys. | group size is related to parasite infections in primates. this relationship probably reflects the fact that group size is associated with body contact between group members and with contact with contaminated items in the environment. the latter is highly associated with range use. in the present study we hypothesized that if infection by directly transmitted parasites (dtp) is mainly determined by the exposure of individuals to parasites that accumulate in the environment, and group size correla ... | 2011 | 21607684 |
| impact of intrasexual selection on sexual dimorphism and testes size in the mexican howler monkeys alouatta palliata and a. pigra. | one of the goals of physical anthropology and primatology is to understand how primate social systems influence the evolution of sexually selected traits. howler monkeys provide a good model for studying sexual selection due to differences in social systems between related species. here, we examine data from the sister howler monkey species alouatta palliata and a. pigra inhabiting southeastern mexico and northern guatemala. we use a resampling approach to analyze differences in sexual dimorphis ... | 2011 | 21826636 |
| [population viability of alouatta palliata (primates: atelidae) and cebus capucinus (primates: cebidae) at refugio de vida silvestre privado nogal, sarapiquí, heredia, costa rica]. | habitat destruction may cause wildlife population fragmentation and is considered an important factor in small population species extinction. as wildlife populations become smaller, threats to their stability and persistence arise as a result of demographic, environmental and genetic stochastic factors. the aim of this work was to study the effects of population fragmentation on the long term viability of alouatta palliata and cebus capucinus populations, at refugio de vida silvestre privado nog ... | 2012 | 23894948 |
| molecular detection of plasmodium malariae/plasmodium brasilianum in non-human primates in captivity in costa rica. | one hundred and fifty-two blood samples of non-human primates of thirteen rescue centers in costa rica were analyzed to determine the presence of species of plasmodium using thick blood smears, semi-nested multiplex polymerase chain reaction (snm-pcr) for species differentiation, cloning and sequencing for confirmation. using thick blood smears, two samples were determined to contain the plasmodium malariae parasite, with snm-pcr, a total of five (3.3%) samples were positive to p. malariae, clon ... | 2017 | 28125696 |
| trypanoxyuris atelis and t. atelophora (nematoda: oxyuridae) in wild spider monkeys (ateles geoffroyi) in tropical rain forest in mexico: morphological and molecular evidence. | two species of pinworms, trypanoxyuris atelis and trypanoxyuris atelophora were collected from the black-handed spider monkey (ateles geoffroyi) in several localities across southeastern mexico, representing the first record for both species in mexican primates. identification of pinworm species was based on morphological and molecular data. these pinworms are distinguished from other congeners, and from each other, by the buccal structure, the lateral alae, and the morphology of the oesophagus. ... | 2015 | 25748278 |
| chromosomal localization of the telomeric (ttaggg)n sequence in eight species of new world primates (neotropical primates, platyrrhini). | chromosomal localization of the telomeric sequence (ttaggg)(n) in eight new world primates (platyrrhini) (alouatta caraya, alouatta palliata, alouatta guariba clamitans, aotus azarae, ateles chamek, cebus nigritus, cebus paraguayanus, and saimiri boliviensis) using fluorescence in situ hybridization (fish) with a peptide nucleic acid (pna) pantelomeric probe and their possible relationship with the c-banding pattern were analyzed. fish showed telomeric signals only at the terminal regions of chr ... | 2007 | 18253032 |
| howler monkey foraging ecology suggests convergent evolution of routine trichromacy as an adaptation for folivory. | primates possess remarkably variable color vision, and the ecological and social factors shaping this variation remain heavily debated. here, we test whether central tenants of the folivory hypothesis of routine trichromacy hold for the foraging ecology of howler monkeys. howler monkeys (genus alouatta) and paleotropical primates (parvorder: catarrhini) have independently acquired routine trichromacy through fixation of distinct mid- to long-wavelength-sensitive (m/lws) opsin genes on the x-chro ... | 2017 | 28261454 |
| pinworm diversity in free-ranging howler monkeys (alouatta spp.) in mexico: morphological and molecular evidence for two new trypanoxyuris species (nematoda: oxyuridae). | two new species of trypanoxyuris are described from the intestine of free-ranging howler monkeys in mexico, trypanoxyuris multilabiatus n. sp. from the mantled howler alouatta palliata, and trypanoxyuris pigrae n. sp. from the black howler alouatta pigra. an integrative taxonomic approach is followed, where conspicuous morphological traits and phylogenetic trees based on dna sequences are used to test the validity of the two new species. the mitochondrial cytochrome oxidase subunit 1 gene, and t ... | 2016 | 27262522 |
| mantled howler monkey spatial foraging decisions reflect spatial and temporal knowledge of resource distributions. | an animal's ability to find and relocate food items is directly related to its survival and reproductive success. this study evaluates how mantled howler monkeys make spatial foraging decisions in the wild. specifically, discrete choice models and agent-based simulations are used to test whether mantled howler monkeys on barro colorado island, panama, integrate spatial information in order to maximize new leaf flush and fruit gain while minimizing distance traveled. several heuristic models of d ... | 2016 | 26597923 |
| intragroup genetic relatedness in two howler monkey species (alouatta pigra and a. palliata): implications for understanding social systems and dispersal. | the degree of genetic relatedness among group members is influenced by dispersal, group formation and composition, mating systems, and other socioecological factors. making inferences about differences between species in their socio-genetic structure is difficult because studies rarely compare multiple species. in this study, we use multilocus microsatellite genotype data to analyze intragroup genetic relatedness in two howler monkey species (alouatta palliata and a. pigra). we test the predicti ... | 2015 | 26422388 |
| characterization of blastocystis species infection in humans and mantled howler monkeys, alouatta palliata aequatorialis, living in close proximity to one another. | this study characterizes blastocystis species infections in humans and mantled howler monkeys, alouatta palliata aequatorialis, living in close proximity to one another in northwestern ecuador. blastocystis species were identified from 58 of 96 (60.4 %) mantled howler monkey fecal samples, and 44 of 55 human fecal samples (81.5 %) by polymerase chain reaction. using single-stranded conformation polymorphism, we were able to efficiently separate and sequence subtypes (sts) within mixed samples wi ... | 2015 | 25859926 |
| gastrointestinal parasites of ecuadorian mantled howler monkeys (alouatta palliata aequatorialis) based on fecal analysis. | an analysis of gastrointestinal parasites of ecuadorian mantled howler monkeys, alouatta palliata aequatorialis, was conducted based on examination of fecal smears, flotations, and sedimentations. at least 1 type of parasite was detected in 97% of the 96 fecal samples screened across 19 howler monkey groups using these techniques. samples averaged 3.6 parasite species per individual (±1.4 sd). parasites included species representing genera of 2 apicomplexans: cyclospora sp. (18% of individual sa ... | 2015 | 25686475 |
| effect of ancestry on behavioral variation in two species of howler monkeys (alouatta pigra and a. palliata) and their hybrids. | social differences between primate species may result from both flexible responses to current conditions or fixed differences across taxa, yet we know little about the relative importance of these factors. here, we take advantage of a naturally occurring hybrid zone in tabasco, mexico to characterize the variation in social structure among two endangered howler monkey species, alouatta pigra and a. palliata, and their hybrids. work in pure populations has suggested that a. pigra females maintain ... | 2014 | 24668503 |
| patterns of infection by intestinal parasites in sympatric howler monkey (alouatta palliata) and spider monkey (ateles geoffroyi) populations in a tropical dry forest in costa rica. | in primate populations, endoparasite species richness and prevalence are associated with host traits such as reproductive and social status, age, sex, host population density, and environmental factors such as humidity. we analyzed the species richness and prevalence of intestinal parasites in two sympatric primate populations, one of alouatta palliata and one of ateles geoffroyi, found in a tropical dry forest in costa rica. we identified three species of intestinal parasites (controrchis sp., ... | 2014 | 24585246 |
| highly nested diets in intrapopulation monkey-resource food webs. | recently several studies have focused on the structure of ecological networks to provide insights into ecological and coevolutionary dynamics of interacting species. however, rarely have the tools of ecological networks been used to understand how feeding relationships vary among individuals of the same population. here we use 7 years of data and network analyzed to examine the intrapopulation diet variation in a group of howler monkeys (alouatta palliata). we show that individual monkey-resourc ... | 2014 | 24497349 |
| the effect of energetic and psychosocial stressors on glucocorticoids in mantled howler monkeys (alouatta palliata). | the proximate causes of variation in glucocorticoids (gcs) of many free-ranging primates are still unclear, and in some cases, the available evidence is contradictory. such is the case of mantled howler monkeys. in the present study, we tested whether variation in gc levels in this species could be predicted by energetic challenges or by psychosocial stressors. we focused on two groups living in los tuxtlas (veracruz, mexico) that differed in a number of parameters including: group size, habitat ... | 2014 | 24282141 |
| limited genetic diversity in the critically endangered mexican howler monkey (alouatta palliata mexicana) in the selva zoque, mexico. | the mexican howler monkey (alouatta palliata mexicana) is a critically endangered primate, which is paleoendemic to mexico. however, despite the potential significance of genetic data for its management and conservation, there have been no population genetic studies of this subspecies. to examine genetic diversity in the key remaining forest refuge for a. p. mexicana, the selva zoque, we amplified full-length mitochondrial control region sequences (1,100 bp) from 45 individuals and found 7 very ... | 2014 | 24276508 |
| differential effects of unusual climatic stress on capuchin (cebus capucinus) and howler monkey (alouatta palliata) populations on barro colorado island, panama. | though the harmful effects anthropogenic disturbances pose to wild primates are well appreciated, comparatively little is known about the effects of natural disturbances. from december 2010 to january 2011, different mortality patterns were observed for two primate species, capuchins and howler monkeys, on barro colorado island (bci), panama. unusually high rainfall in 2010 was associated with census and cadaver data indicating the rapid loss of >70% of the capuchin population in late 2010 to ea ... | 2014 | 24273098 |
| behavioral and physiological responses to subgroup size and number of people in howler monkeys inhabiting a forest fragment used for nature-based tourism. | animals' responses to potentially threatening factors can provide important information for their conservation. group size and human presence are potentially threatening factors to primates inhabiting small reserves used for recreation. we tested these hypotheses by evaluating behavioral and physiological responses in two groups of mantled howler monkeys (alouatta palliata mexicana) at the "centro ecológico y recreativo el zapotal", a recreational forest reserve and zoo located in the mexican st ... | 2013 | 23801542 |
| clarifying the cryptic host specificity of blastocystis spp. isolates from alouatta palliata and a. pigra howler monkeys. | although the presence of cryptic host specificity has been documented in blastocystis, differences in infection rates and high genetic polymorphism within and between populations of some subtypes (st) have impeded the clarification of the generalist or specialist specificity of this parasite. we assessed the genetic variability and host specificity of blastocystis spp. in wild howler monkeys from two rainforest areas in the southeastern region of mexico. fecal samples of 225 alouatta palliata (5 ... | 2017 | 28056072 |
| an assessment of skin temperature gradients in a tropical primate using infrared thermography and subcutaneous implants. | infrared thermography has become a useful tool to assess surface temperatures of animals for thermoregulatory research. however, surface temperatures are an endpoint along the body's core-shell temperature gradient. skin and fur are the peripheral tissues most exposed to ambient thermal conditions and are known to serve as thermosensors that initiate thermoregulatory responses. yet relatively little is known about how surface temperatures of wild mammals measured by infrared thermography relate ... | 2017 | 28010815 |
| wear and its effects on dental topography measures in howling monkeys (alouatta palliata). | three dental topography measurements: dirichlet normal energy (dne), relief index (rfi), and orientation patch count rotated (opcr) are examined for their interaction with measures of wear, within and between upper and lower molars in alouatta palliata. potential inferences of the "dental sculpting" phenomenon are explored. | 2016 | 27634058 |
| genetic, spatial, and social relationships among adults in a group of howler monkeys (alouatta palliata) from barro colorado island, panama. | kinship plays an important role in the social behavior of many primate species, including patterns of intra-group affiliation and cooperation. within social groups, kinship is strongly affected by dispersal patterns, with the degree of relatedness among group-mates expected to decrease as the tendency to disperse increases. in primate species characterized by bisexual dispersal, relatedness among adult group-mates is predicted to be low, with social interactions shaped largely by factors other t ... | 2016 | 26935548 |
| measures of food intake in mantled howling monkeys. | food intake (i.e., the amount of food consumed by an individual) is a crucial measure for studying feeding behavior, but its measurement requires high visibility of individuals and long recording sessions, which are often difficult to accomplish under field conditions. as a consequence, studies on the feeding behavior of primates typically do not estimate food intake directly, and focus rather on studying dietary patterns through indirect measures of food intake, such as time spent feeding, numb ... | 2016 | 26801340 |
| dust in the wind: how climate variables and volcanic dust affect rates of tooth wear in central american howling monkeys. | two factors have been considered important contributors to tooth wear: dietary abrasives in plant foods themselves and mineral particles adhering to ingested food. each factor limits the functional life of teeth. cross-population studies of wear rates in a single species living in different habitats may point to the relative contributions of each factor. | 2016 | 26426839 |
| testing parallel laser image scaling for remotely measuring body dimensions on mantled howling monkeys (alouatta palliata). | body size is a fundamental variable for many studies in primate biology. however, obtaining body dimensions of wild primates through live capture is difficult and costly, so developing an alternative inexpensive and non-invasive method is crucial. parallel laser image scaling for remotely measuring body size has been used with some success in marine and terrestrial animals, but only one arboreal primate. we further tested the efficacy of this method on the arboreal mantled howling monkey (alouat ... | 2015 | 25931319 |
| quantifying the severity of hurricanes on extinction probabilities of a primate population: insights into "island" extirpations. | long-term studies quantifying impacts of hurricane activity on growth and trajectory of primate populations are rare. using a 14-year monitored population of alouatta palliata mexicana as a study system, we developed a modeling framework to assess the relative contribution of hurricane disturbance and two types of human impacts, habitat loss, and hunting, on quasi-extinction risk. we found that the scenario with the highest level of disturbance generated a 21% increase in quasi-extinction risk b ... | 2015 | 25845567 |