Resumen Introducción: Los patrones hematológicos de la vida silvestre son fundamentales para el monitoreo de la salud y permiten dilucidar las variaciones tanto dentro como entre poblaciones. Entre estos, los parámetros hematológicos son particularmente valiosos para evaluar el estado de salud de las especies de primates neotropicales en la naturaleza. Objetivo: Definir valores de referencia hematológicos para dos especies de monos en Costa Rica. Métodos: Durante el 2014 recolectamos muestras de sangre de monos aulladores de manto, Alouatta palliata (17 hembras, 18 machos) y monos capuchinos cariblancos, Cebus imitador (5 hembras, 7 machos) en siete localidades de la costa Pacífica de Costa Rica. Resultados: Para ambas especies, los valores hematológicos fueron mayores en los machos, y las poblaciones de monos aulladores difirieron significativamente con excepción de las plaquetas. Conclusiones: Estos valores hematológicos, que difieren según el sexo y la localidad, ayudarán a evaluar el estado de salud de estas poblaciones de primates neotropicales.

Abstract Introduction: Wildlife hematological patterns are fundamental for health monitoring, and allows elucidating variations both within and between populations. Among these, hematological parameters are particularly valuable to evaluate the health status of neotropical primate species in the wild. Objective: To define hematological reference values for two species of monkeys in Costa Rica. Methods: During 2014, we collected blood samples from free-ranging mantled howler monkeys, Alouatta palliata (17 females, 18 males) and white-faced capuchin monkeys, Cebus imitator (5 females, 7 males) in seven localities of the Costa Rican Pacific coast. Results: For both species, the hematological values were higher in males, and howler monkey populations differed significantly except for platelets. Conclusions: These hematological values, which differ by sex and locality, will help evaluate the health status of these neotropical primate populations.

RESUMEN Los estudios de citogenética en Primates Neotropicales (Primates: Platyrrhini) han demostrado que estos mamíferos comprenden un grupo heterogéneo a nivel cromosómico. La notable variedad de cariotipos descriptos provee evidencia significativa sobre el posible papel de los reordenamientos cromosómicos en su evolución. En el Grupo de Investigación en Biología Evolutiva (GIBE), la línea de investigación sobre el proceso de divergencia evolutiva en Platyrrhini considerando distintos aspectos de la organización del genoma se ha establecido y desarrollado de manera ininterrumpida desde hace más de 30 años. Entre los avances realizados en los últimos años se encuentra la cuantificación del tamaño del genoma en seis especies de monos caí (Cebus sp.) y dos especies de monos aulladores (Alouatta sp.) y la descripción de la composición de pares de bases en las regiones de heterocromatina constitutiva en los géneros Cebus y Ateles. Se concretaron las primeras descripciones del cariotipo y comportamiento meiótico en profase I temprana de dos especies de monos aulladores, Alouatta caraya y A. guariba clamitans. En esta última especie se identificó el primer sistema sexual de tipo pentavalente X1X2X3Y1Y2 en una especie de primate. Se caracterizó la organización de la eucromatina en términos del contenido y distribución de bases nucleotídicas AT y GC en tres especies de aulladores y en dos especies de monos caí. Estas investigaciones, entre otras, permitieron contribuir de forma original al conocimiento sobre la especiación en distintos niveles, así como sobre la arquitectura y dinámica del genoma de estos primates.

ABSTRACT Cytogenetics studies in Neotropical Primates (Primates: Platyrrhini) have shown that these mammals comprise a heterogeneous group at the chromosomal level. The remarkable variety of karyotypes described provides significant evidence on the possible role of chromosomal rearrangements in their evolution. In the Grupo de Investigación en Biología Evolutiva (GIBE), the line of research on the evolutionary divergence process in Platyrrhini considering different aspects of the organization of the genome has been established and developed uninterruptedly for more than 30 years. Among the advances made in recent years is the quantification of the genome size in six species of caí monkeys (Cebus sp.) and two species of howler monkeys (Alouatta sp.) and the description of the composition of base pairs in the constitutive heterochromatin regions in the genera Cebus and Ateles. The first descriptions were made of the karyotype and meiotic behavior in early prophase I of two species of howler monkeys, Alouatta caraya and A. guariba clamitans. In this last species, the first pentavalent-type sexual system X1X2X3Y1Y2 was identified in a primate species. The organization of euchromatin was characterized in terms of the content and distribution of AT and GC nucleotide bases in three species of howlers and in two species of caí monkeys. These, among other investigations, allowed contributing in an original way to the knowledge about speciation at different levels, as well as about the architecture and dynamics of the genome of these primates.

Resumen: Antecedentes y Objetivos: Diversos estudios han destacado el importante papel de los monos aulladores (Alouatta palliata mexicana) en la dispersión de semillas y, con ello, en la regeneración de las poblaciones de plantas con frutos carnosos de los bosques tropicales. Sin embargo, poca es la evidencia empírica sobre cuáles podrían ser los mecanismos que les permitiría a los monos aulladores favorecer la germinación de las semillas de muchas especies de plantas, incluyendo la escarificación de su cubierta externa. En este trabajo se evaluó si los endocarpos de Spondias mombin (Anacardiaceae), una especie importante en la dieta de los monos aulladores, podrían ser escarificados al pasar por el tracto digestivo de estos primates. Métodos: Se colectaron endocarpos de las heces de monos aulladores, así como frutos maduros del suelo, en la región de Los Tuxtlas, municipio Catemaco, Veracruz, México. Mediante cortes transversales de los endocarpos y su análisis en el microscopio electrónico de barrido, se tomaron medidas del grosor de la cubierta externa y probaron las diferencias entre ambos tipos de muestras (i.e., endocarpos de frutos y endocarpos que pasaron por el tracto digestivo). Resultados clave: Se observó que el grosor de la cubierta de los endocarpos en frutos fue mayor ( X ~=47.05±9.69 µm) que el de endocarpos en heces ( X ~=1.51±3.60 µm) (W=0.48, p<0.001). Conclusiones: Los resultados evidencian que la ingesta de endocarpos de S. mombin por A. p. mexicana puede tener un efecto de escarificación de los tejidos que conforman su cubierta externa. Esto apoya la versión sobre la función de los frugívoros, como los monos aulladores, reduciendo la cubierta externa de las semillas y aumentando así su capacidad para germinar; siendo, por lo tanto, organismos clave en la dinámica de regeneración de bosques tropicales.

Abstract: Background and Aims: Several studies have emphasized the important role of howler monkeys (Alouatta palliata mexicana) in seed dispersal and, as a result, in the regeneration of fleshy-fruited plant populations in tropical forests. However, there is little empirical evidence regarding the possible mechanisms that would allow howler monkeys to promote seed germination of many plant species, including seed coat scarification. In this study, we evaluated whether endocarps of Spondias mombin (Anacardiaceae), an important species in howler monkey diet, could be scarified by passage through the digestive tract of these primates. Methods: We collected endocarps from howler monkey feces as well as ripe fruits fallen on the ground, in the region of Los Tuxtlas, Catemaco municipality, Veracruz, Mexico. By analyzing endocarp transverse sections using a scanning electron microscope, we measured the thickness of the outer layer and tested differences between both types of samples (i.e., fruit endocarps and endocarps that had passed through the digestive tract). Key results: We observed that the outer layer thickness of endocarps in fruits was greater ( X ~=47.05±9.69 µm) than that of endocarps found in feces ( X ~=1.51±3.60 µm) (W=0.48, p<0.001). Conclusions: Our results highlight that consumption of S. mombin endocarps by A. p. mexicana may have a scarification effect on the tissues that constitute the outer layer. This supports the hypothesis of the role of frugivores, such as howler monkeys, in reducing the seed coat and thus increasing germination ability; therefore, being key organisms in regeneration dynamics of tropical forests.

RESUMO: O bugio ruivo (Alouatta guariba clamitans) é uma espécie de primata amplamente distribuída na América do Sul. As infecções por protozoários são comuns em primatas. Entretanto, estudos sobre protozoários em primatas no Brasil são escassos, portanto o objetivo deste estudo foi pesquisar DNA dos protozoários Apicomplexa Neospora caninum, Sarcocystisspp. e Toxoplasma gondii em tecidos de A. guariba clamitans. A extração de DNA foi realizada em amostras de tecido do coração, cérebro, fígado, baço, pulmão e intestino de seis A. guariba clamitans oriundos de Santa Maria, Região Central do Rio Grande do Sul, Brasil. Foi realizada PCR convencional utilizando primers geral do gene 18S rRNA para Apicomplexa e também primers específicos para amplificação de DNA de Neospora spp.e Toxoplasma gondii. Todos os animais foram positivos no PCR geral para Apicomplexa e no sequenciamento genético confirmou-se a presença de DNA de Sarcocystis nos tecidos de quatro animais pertencentes a pelo menos duas espécies (S. neurona e S. gigantea), e DNA de T. gondii foi detectado nos outros dois animais. Uma amostra positiva para T. gondii foi caracterizada genotipicamente como atípico pela técnica de polimorfismo do comprimento do fragmento de restrição. Não foi detectado DNA de N. caninum nas amostras testadas. A presença de DNA de protozoários apicomplexa nos tecidos dos seis animais testados neste estudo destaca a importância dos bugios ruivos como mantenedores desses patógenos na natureza.

ABSTRACT: The brown howler monkey (Alouatta guariba clamitans) is a primate species widely distributed in South America. Infections by protozoa are common in primates. However, studies on protozoa in primates in Brazil are scarce, so the goal of this study was to investigate DNA from the apicomplexan protozoa Neospora caninum, Sarcocystis spp. and Toxoplasma gondii in tissues of A. guariba clamitans. DNA extraction was performed on tissue samples from the heart, brain, liver, spleen, lung and intestine of six A. guariba clamitans from Santa Maria, Central Region of Rio Grande do Sul, Brazil. Conventional PCR was performed using 18S rRNA gene general primers for Apicomplexa and also specific primers to amplify Neosporaspp. and Toxoplasma gondii DNA. All animals were positive in the 18S PCR and the genetic sequencing confirmed the presence of Sarcocystis spp. DNA in the tissues of four animals belonging to at least two species (S. neurona and S. gigantea) and T. gondii DNA in the other two animals. One positive sample for T. gondii was genotypically characterized as atypical by the restriction fragment length polymorphism technique. N. caninum DNA was not detected in the tested samples. The presence of Apicomplexa protozoan DNA in the tissues of the six animals tested in this study highlights the importance of howler monkeys as maintainers of these pathogens in nature.

Abstract: Studies have shown that as age increases, parasitism could also be more frequent, on the other hand, the lack of immunity can increase the risk of infection in younger individuals. Regarding sex, there is a general tendency for males to be more parasitized than females, in the case of primates, this is related to the effort made by males into attaining and maintain a high rank, implying high levels of testosterone, a hormone with immunosuppressive effects. Immunosuppressive effects of stress hormones can also increase susceptibility in dominant or subordinate individuals, nevertheless, in a study, the level of exposure to parasites seems to be more important than the immunosuppressive effects of stress in explaining why dominant females have more infections from directly transmitted parasites. In this study, we investigated the relationship between the prevalence of Giardia spp. and Blastocystis spp. and the categories of age and sex in black and golden howler monkeys (Alouatta caraya) of Argentina. We analyzed 375 fecal samples from 27 individuals (juveniles and adults of both sexes), using microscopy and techniques of flotation and sedimentation. To analyze the relationship between age, sex, and infection prevalence, a Generalized Linear Mixed Model was used. In adults, the prevalence of infection was 78.5 % while in juveniles, all individuals (100 %) were infected with both protozoa. Males had a infection prevalence 84.6%, in females it was 92.8 %. When comparing infection prevalence between ages and between sexes, no significant differences were found (P > 0.05). Research suggests that parasite infection rates may be influenced by specific form of transmission, in this sense, these protozoa, are transmitted through ingestion of cysts which are infectious immediately after defecation has occurred. On the other hand, all members of the group tend to defecate simultaneously, leaving all the members of the group exposed to infection. Therefore, we suggest that physiological or behavioral factors do not appear to be important in the risk of protozoan infection.

Resumen: Algunos estudios han demostrado que a medida que aumenta la edad, el parasitismo también podría aumentar, por otro lado, la falta de inmunidad puede incrementar el riesgo de infección en individuos más jóvenes. En cuanto al sexo, existe una tendencia general a que los machos estén más parasitados que las hembras, en el caso de los primates, esto está relacionado al esfuerzo que realizan los machos para alcanzar y mantener un alto rango, implicando niveles elevados de testosterona, una hormona con efectos inmunosupresores. Efectos inmunosupresores de las hormonas del estrés también pueden incrementar la susceptibilidad en individuos dominantes o subordinados, sin embargo, en un estudio, el nivel de exposición a parásitos parece ser más importante que los efectos inmunosupresores del estrés para explicar por qué las hembras dominantes tienen más infecciones por parásito. En este estudio, investigamos la relación entre la prevalencia de Giardia spp. y Blastocystis spp. y las categorías de edad y sexo en monos aulladores negros y dorados (Alouatta caraya) de Argentina. Se analizaron 375 muestras fecales de 27 individuos (juveniles y adultos de ambos sexos), mediante microscopia y técnicas de flotación y sedimentación. Para analizar la relación entre edad, sexo y prevalencia de infección se utilizó un Modelo Lineal Generalizado Mixto. En adultos, la prevalencia de infección fue del 78.5 %, mientras que, en los juveniles, todos los individuos (100 %) estuvieron infectados con ambos protozoos. Los machos tuvieron una prevalencia de infección de 84.6 %, y las hembras 92.8 %. Al comparar la prevalencia de infección entre edades y entre sexos, no se encontraron diferencias significativas (P > 0.05). Investigaciones sugieren que las tasas de infección parasitaria pueden ser afectadas por la forma de transmisión, en este sentido, estos protozoos, se transmiten a través de la ingestión de quistes, lo cuales son infecciosos inmediatamente después de la defecación. Por otro lado, todos los miembros del grupo tienden a defecar simultáneamente, contribuyendo a la presencia de áreas contaminadas con heces, dejando a todos los miembros del grupo expuestos a la infección. Por lo tanto, sugerimos que los factores fisiológicos o de comportamiento no parecen ser importantes en el riesgo de infección por protozoos.

RESUMEN Existe una creciente evidencia de que la sociabilidad en primates no humanos está relacionada con mecanismos neuroendocrinos. La arginina vasopresina, las endorfinas y la oxitocina pueden estar involucradas en tales mecanismos. Aquí, realizamos un análisis preliminar de los correlatos sociales de la variación en las concentraciones de oxitocina urinaria en monos aulladores de manto (Alouatta palliata). De enero a diciembre de 2017, estudiamos 13 monos aulladores de manto adultos pertenecientes a dos grupos. Registramos la ocurrencia de interacciones sociales (547.5 horas de observación); evaluamos la proximidad entre los miembros del grupo (2.194 registros instantáneos); y recolectamos 172 muestras de orina. Analizamos las muestras de orina (ELISA) para determinar las concentraciones de oxitocina, las cuales corregimos por la gravedad específica, lo que resultó en 54 muestras analizadas. Con respecto a cuando no ocurrieron interacciones afiliativas, las concentraciones de oxitocina aumentaron aproximadamente un 62% cuando los individuos participaron en interacciones afiliativas, y las concentraciones de oxitocina fueron mayores cuando díadas con una relación social de baja calidad se afiliaron. Estos resultados convergen con propuestas previas de que la oxitocina está vinculada a la participación en interacciones afiliativas. La convergencia entre estos resultados y los reportados para otros taxa apoya la hipótesis de que los mecanismos biológicos que permiten la sociabilidad de los primates se comparten entre las especies.

ABSTRACT There is growing evidence that non-human primate sociality is linked to proximate neuroendocrine mechanisms. Arginine vasopressin, endorphins, and oxytocin may be involved in such mechanisms. Here, we perform a preliminary analysis of the social correlates of variation in urinary oxytocin concentrations in mantled howler monkeys (Alouatta palliata). From January to December 2017, we studied 13 adult mantled howler monkeys belonging to two groups. We recorded the occurrence of social interactions (547.5 observation hours); assessed proximity among group members (2,194 instantaneous recordings); and collected 172 urine samples. Urine samples were assayed (ELISA) for oxytocin concentrations, which were corrected for specific gravity, resulting in 54 analyzed samples. Hormone concentrations increased by approximately 62% when individuals were involved in affiliative interactions. With respect to when no affiliative interactions occurred, urinary oxytocin concentrations were higher when dyads with a low-quality social relationship affiliated. These results agree with previous contentions that this hormone is linked to participation in affiliative interactions. Convergence between these and results from other taxa supports the hypothesis that the biological mechanisms that allow for primate sociality are shared among species.

RESUMO Seiscentos primatas neotropicais foram submetidos a exames post mortem para avaliação da prevalência parasitária de helmintos gastrointestinais. Foram examinados 556 calitriquídeos (Callithrix spp.), 23 bugios (Alouatta guariba), 19 macacos-pregos (Sapajus nigritus), um mico-leão-dourado (Leontopithecus rosalia) e um mico-leão-da-cara-dourada (Leontopithecus chrysomelas). Do total de 600 animais, foram encontrados espécimes parasitos pertencentes aos filos Acanthocephala, Nemathelmintes e Platyhelminthes (classes Trematoda e Cestoda) em 110 primatas. A prevalência de primatas positivos para, pelo menos, uma espécie de helminto foi de 18,3% (110/600), sendo destes 83,6% (92/110) calitriquídeos, 8,2% (9/110) bugios, 6,4% (7/110) macacos-pregos, 0,9% (1/110) mico-leão-dourado e 0,9% (1/110) mico-leão-da-cara dourada. Em 80,4% (74/92) dos calitriquídeos foram encontrados nematoides Primasubulura sp. e em 1,1% (1/92) nematoides Trypanoxyuris callithrix, em 26,1% (24/92) acantocéfalos (Pachysentis sp.) e em 5,4% (5/92) digenéticos (Platynosomum sp.); em 77,8% (7/9) dos bugios foram encontrados nematoides (Trypanoxyuris minutus), em 11,1% (1/9) acantocéfalos (Pachysentis sp.) e em 11,1% (1/9) cestoides (Bertiella sp.); em 14,3% (1/7) dos macacos-pregos foram encontrados nematoides (Physaloptera sp.), em 28,6% (2/7) acantocéfalos (Prostenorchis sp.) e em 14,3% (1/7) digenéticos (Platynosomum sp.) e no mico-leão-da-cara-dourada foram encontrados acantocéfalos (Prostenorchis sp.). Foi realizado o georreferenciamento dos pontos de encontro dos cadáveres para pontuar a distribuição dos helmintos por região.

ABSTRACT Six hundred neotropical primates underwent postmortem examinations to evaluate the parasitic prevalence of gastrointestinal helminths. Fifty-five callitrichids tamarins (Callithrix spp.), 23 howlers (Alouatta guariba), 19 nail monkeys (Sapajus nigritus), a golden lion tamarin (Leontopithecus rosalia) and a golden-faced lion tamarin (Leontopithecus chrysomelas) were examined. Parasitic specimens belonging to phylums Acantocephala, Nemathelmintes and Platyhelmintes (Trematoda and Cestoda Classes) were found. The prevalence of primates positive for at least one species of helminth was 18.3% (110/600), of which 83.6% (92/110) callitrichids, 8.2% (9/110) howler monkeys, 6.4% (7/110) capuchin monkeys, 0.9% (1/110) golden lion tamarin and 0.9% (1/110) golden faced lion tamarin. In 80.4% (74/92) of callitrichids nematodes (Primasubulura sp.) were found, and in 1.1% (1/92) nematodes (Trypanoxyuris callithricis), in 26.1% (24/92) acanthocephalus (Pachysentis sp.) and 5.4% (5/92) digenetics (Platynosomum sp.); in 77.8% (7/9) of howler monkeys presented nematodes (Trypanoxyuris minutus), 11.1% (1/9) acanthocephalus (Pachysentis sp.) and 11.1% (1/9) cestoids (Bertiella sp.); in 14.3% (1/7) of capuchin monkeys presented nematodes (Physaloptera sp.), 28.6% (2/7) acanthocephalus (Prostenorchis sp.) and 14.3% (1/7) digenetics (Platynosomum sp.) and in the golden-faced lion tamarin acanthocephalus (Prostenorchis sp.) were found. Georreferencing of the meeting points of the cadavers was performed in order to punctuate the distribution of helminths by region.

BACKGROUND The influence of Plasmodium spp. infection in the health of Southern brown howler monkey, Alouatta guariba clamitans, the main reservoir of malaria in the Atlantic Forest, is still unknown. OBJECTIVES The aim of this study was to investigate the positivity rate of Plasmodium infection in free-living howler monkeys in an Atlantic Forest fragment in Joinville/SC and to associate the infection with clinical, morphometrical, haematological and biochemical alterations. METHODS Molecular diagnosis of Plasmodium infection in the captured monkeys was performed by Nested-polymerase chain reaction (PCR) (18S rRNA and coxI). Haematological and biochemical parameters were compared among infected and uninfected monkeys; clinical and morphometrical parameters were also compared. FINDINGS The positivity rate of Plasmodium infection was 70% among forty captured animals, the highest reported for neotropical primates. None statistical differences were detected in the clinical parameters, and morphometric measures comparing infected and uninfected groups. The main significant alteration was the higher alanine aminotransferase (ALT) levels in infected compared to uninfected monkeys. MAIN CONCLUSIONS Therefore, Plasmodium infection in howler monkeys may causes haematological/biochemical alterations which might suggest hepatic impairment. Moreover, infection must be monitored for the eco-epidemiological surveillance of malaria in the Atlantic Forest and during primate conservation program that involves the animal movement, such as translocations.

A efetividade de um dispersor de sementes depende, dentre outros fatores ainda pouco compreendidos em relação a muitos primatas Neotropicais, do tempo em que as sementes são mantidas no trato digestivo do animal. Este estudo testou o efeito do sexo, tamanho da semente e teor de fibra alimentar sobre o tempo de retenção de sementes no trato digestivo de bugios pretos (Alouatta caraya). As sessões experimentais foram realizadas com seis indivíduos cativos (três de cada sexo), seis espécies de sementes distribuídas em três classes de tamanho (pequenas, médias e grandes) e três porções de folhas na dieta (15, 30 e 60% do alimento total ingerido). Os tempos de retenção foram registrados em 1767 sementes recuperadas, correspondendo a 55% do total ingerido. Mais de 98% dessas sementes foram defecadas intactas, sugerindo o potencial dos bugios como dispersores de sementes. O sexo, o tamanho da semente e o teor de fibras alimentares não apresentaram efeito sobre o tempo de retenção, mas a interação entre sexo e tamanho da semente mostrou um efeito sobre a média do tempo de retenção, com tendência a diminuir para machos e aumentar para fêmeas à medida que o tamanho da semente aumenta. Deste modo, machos e fêmeas podem ter influências complementares nos padrões de recrutamento e dispersão para diferentes espécies de plantas, contribuindo para a diversidade da comunidade.

The effectiveness of a seed disperser depends, among various factors still poorly understood for many Neotropical primates, on the amount of time seeds are retained within its digestive tract. This study tested the effects of sex, seed size and dietary fiber content on seed retention time in the digestive tract of black howler monkeys (Alouatta caraya). Experiments were performed using six captive individuals (three of each sex), six seed species distributed in three size classes (small, medium, and large), and three percentages of leaves in the diet (15, 30 and 60% of total food ingested). Retention times were recorded for 1767 recovered seeds, corresponding to 55% of the total ingested. More than 98% of these seeds were undamaged, suggesting the potential role of howlers as seed dispersers. Sex, seed size and dietary fiber content alone showed no effect on retention time, but the interaction between sex and seed size showed an effect on the mean retention time, which tended to decrease for males and increase for females as the seed size increased. Thus, males and females may have complementary influences on recruitment and dispersion patterns for different plant species, contributing to community diversity.

RESUMO Este artigo discute parte das práticas de conhecimento relativas aos animais e à caça de macacos entre os Guajá, considerando o processo de destruição de seus territórios. O artigo explicita conexões feitas e refeitas continuamente, em um regime que relaciona humanos e animais, sem, no entanto, recorrer à ideia de que caça e criação seriam formas complementares de relação com os animais. Sugiro que as maneiras como humanos e bugios vivem juntos talvez encontre aqui outra forma de pensar a própria ideia de “espécie”. O desafio a mais do artigo está em refletir, a partir dessa “noção indígena de espécie”, como poderíamos pensar outros fenômenos, por exemplo, o surto de febre amarela experimentado no Sudeste brasileiro no ano de 2017.

ABSTRACT This article explores part of the Guajá knowledge practices related to animals and to the hunting of howler monkeys, considering the ongoing process of their territory destruction. The article puts forward the connections, constantly done and undone, in a regime that relates humans and animals in many ways. There is no intention, however, to appeal to the idea that hunting and nurturing would be complementary ways of relating to animals. The challenge of understanding revealed by the ways that humans and monkeys live together, may point to an alternative form to think the very concept of “species”. The extra challenge of this article is to explore, from this “notion of species”, how could we think other phenomena, such as, for instance, the yellow fever burst experienced in the southeast Brazil in 2017.

Abstract: Habitat disturbance disrupts the ecological interactions of mammals, leading to negative consequences for biodiversity. In particular, it is suggested that parasite-host interactions are affected in tropical ecosystems, with parasite diversity reduced as environmental perturbations take place. In this study, we examined whether the disruption of tropical forests affects the presence of parasites in a population of endangered black howler monkeys (Alouatta pigra) that inhabits a highly fragmented landscape in Balancán, Tabasco, Mexico. Our working hypothesis was that increased forest perturbation would negatively affect the incidence of parasitic infections (parasite presence and richness) in black howler monkeys. We conducted a parasitological study and collected stool samples from 65 adult individuals living in 30 forest fragments across a disturbance gradient. We recovered parasite eggs from stool samples using flotation and sedimentation techniques. We selected fragment size and distance from each forest fragment to the nearest village as measures of forest perturbation. We analyzed the effects of forest perturbation on parasite presence and richness using generalized linear models. Other driving factors such as seasonality, host density, and sex were also considered in the models. Gastrointestinal parasite infection was positively related to distance between forest fragments and the nearest human settlement (β = 0.55 ± SE 0.28, z = 2.0, P = 0.05). No effects of fragment size or any other variable considered in the model on the presence of parasite infection were observed. Parasite richness was not affected by any of the measures of forest perturbation, nor by any other variables considered in the analysis. Our findings suggest that an increase in forest perturbation may negatively affect the probability of parasite infection in black howler monkeys, as individuals living in close proximity to human settlements showed a lower presence of parasites. We proposed that the low parasite infection rates recorded in this monkey population reflect synergistic effects associated with both the alteration of the parasite-primate network, as well as the low resilience of parasites to thrive in a disrupted ecosystem.

Resumen: Los disturbios de hábitat alteran las interacciones ecológicas de los mamíferos con consecuencias negativas para la biodiversidad. En particular, se ha observado que en los ecosistemas tropicales las interacciones entre parásitos y primates son afectadas, y la riqueza de parásitos es reducida conforme aumenta el grado de perturbación ambiental. En este estudio exploramos los efectos de la presión antrópica sobre la presencia y riqueza de parásitos gastrointestinales de una población de monos aulladores negros (Alouatta pigra) que habitan un paisaje altamente fragmentado en Balancán, Tabasco, México. Predecimos que un incremento en la perturbación del bosque afectará negativamente medidas de infección parasitaria (presencia y riqueza de parásitos) en monos aulladores negros. Llevamos a cabo un estudio coproparasitológico y colectamos muestras fecales de 65 individuos adultos que habitan 30 fragmentos de bosque a lo largo de un gradiente de perturbación. A través de técnicas de concentración por flotación y sedimentación recuperamos huevos de parásitos. Seleccionamos el tamaño de los fragmentos habitados por monos y la distancia que existe entre un fragmento y el poblado más próximo como medidas de perturbación del bosque. Analizamos los efectos de la perturbación del bosque sobre medidas de infección parasitaria usando modelos lineales generalizados. Otras variables como la estacionalidad, la densidad de hospederos y el sexo de individuos también fueron consideradas en los modelos. Encontramos que la distancia entre un fragmento de bosque y el poblado más cercano predice positivamente la presencia de infección parasitaria (β = 0.55 ± EE 0.28, z = 2.0, P = 0.05). Ninguna otra variable tuvo efectos significativos sobre la presencia de parásitos. Las medidas de perturbación del bosque y otras variables consideradas no tuvieron efectos significativos sobre la riqueza de parásitos. Nuestros resultados indican que la presencia de parásitos gastrointestinales disminuye en hospederos que habitan fragmentos que se encuentran en cercanía a asentamientos humanos, lo cual sugiere que un incremento en el grado de perturbación del bosque reduce el parasitismo en monos aulladores negros. Proponemos que las bajas tasas de parasitismo observadas en esta población de monos aulladores reflejan una sinergia derivada de la reducción en la conectividad entre parásitos y hospederos, y de la poca resiliencia de los parásitos para sobrevivir en un ecosistema altamente transformado.

Abstract: The interaction between primate groups and the dynamics involved in the use of space are important factors affecting both competition for resources and intergroup dominance. In the present study we analyzed the differences in home range overlap and intergroup size, as well as the diversity of tree species within the home range, the Value Index for the key tree species, and the daily activity pattern of two neighboring groups of the howler monkey Alouatta palliata. From March 2002 to June 2003, the behavior and location of two groups of monkeys (G1, two adult males, four adult females and four infants; G2, six adult males, five adult females, one juvenile and three infants) were recorded in the same forest patch at Los Tuxtlas Biosphere Reserve, Veracruz, Mexico. Using the Minimum Convex Polygon (100 %), grid (100 m), and Kernel (adapted and fixed) methods, as well as transect sampling, significant differences (F1, 20 = 14.45, P = 0.001) were found in the home range size of the groups, being greater in G2. The habitat in the G2 home range had greater richness and diversity of tree species, as well as a higher Importance Value Index for the key tree species (Ficus spp.) included in the howler monkey diet. On the other hand, significant differences between groups (Mann-Whitney U = 38, P < 0.05) were found only as regards locomotion behavior, likely due to a behavioral adaptation to optimize food resource use or search. The two groups displayed a similar use of food resources; however, there was a slight overlap in the home range between both groups with no direct aggression, likely because their habitat included sufficient space and food. Our data suggest that the reduced overlap may vary between neighboring groups because of factors such as group size. However, groups could weigh various factors to avoid home-range overlap.

Resumen: La interacción entre grupos vecinos de primates y la dinámica en el uso del espacio son factores importantes durante la competencia por los recursos y la dominancia intergrupal. En este trabajo analizamos las diferencias intergrupales con relación al tamaño y traslape del ámbito hogareño así como la diversidad de especies arbóreas, el Índice de Valor de Importancia de especies clave y el patrón diario de actividad de dos grupos vecinos de monos aulladores Alouatta palliata mexicana. De marzo 2002 a junio 2003 registramos la conducta y las ubicaciones de dos grupos de monos (formados, G1 por 2 machos adultos, 4 hembras adultas y 4 infantes, y G2 por 6 machos adultos, 5 hembras adultas, 1 joven y 3 infantes) en un mismo fragmento en la Reserva de la Biósfera Los Tuxtlas, Los Tuxtlas, Veracruz, México. Aplicando los métodos de Polígono Mínimo Convexo (100 %), Rejillas (100 m), y Kernel (adaptado y fijo) así como un muestreo por transectos se encontraron diferencias significativas (F1, 20 = 14.45, P = 0.001) en el ámbito hogareño de los grupos, siendo mayor el de G2. El hábitat en el ámbito hogareño del G2 tuvo una mayor riqueza y diversidad de especies arbóreas así como un valor más elevado en el Índice de Valor de Importancia de especies clave (Ficus spp.) en la dieta de los monos aulladores. Por otra parte, se encontraron diferencias significativas (Mann-Whitney U = 38, P < 0.05) sólo en la conducta de locomoción, posiblemente debido a un ajuste conductual para optimizar el aprovechamiento o la búsqueda de recursos alimentarios. Los recursos alimentarios utilizados por los dos grupos fueron similares; sin embargo, se registró un reducido traslape del ámbito hogareño entre los grupos y ningún tipo de agresión directa, lo cual puede deberse a que encuentran suficiente espacio y alimento en el hábitat. Nuestros datos sugieren que el reducido traslape puede variar entre grupos vecinos a causa de factores como el tamaño del grupo. Sin embargo, es posible que los grupos decidan ponderar diversos factores a fin de evitar los traslapes de ámbito hogareño.

Abstract: Habitat loss and fragmentation are major threats to Mexican mantled monkey (Alouatta palliata mexicana), which have reduced drastically the size of its natural populations. This reduction causes a negative impact on its genetic diversity, which in turns threatens the viability of its remnant populations. In this study, genetic diversity is determined in 4 groups of howler monkeys inhabiting continuous and 3 in fragmented forest sections at Los Tuxtlas Biosphere Reserve. DNA was extracted from fecal samples, and 13 microsatellite loci were analyzed, which resulted in 8 polymorphic loci. Our results suggest low levels of genetic diversity (Ho = 0.14, He=0.23 and Na = 2.88) and low genetic differentiation (Fst = 0.043, p = .01) between continuous and fragmented habitats. We found no significant differences between groups or habitat type in any of the genetic diversity parameters analyzed. The inbreeding index was positive for each group and significantly different from zero in continuous and fragmented habitats, indicating heterozygosity deficiency in both ecological conditions. We discuss the results in relation to colonization history of howler monkeys and forest fragmentation.

Resumen: El mono aullador de manto Alouatta palliata mexicana es una subespecie mexicana cuyas poblaciones se han reducido por la pérdida y fragmentación de su hábitat. Esta alteración del hábitat tiene un impacto negativo sobre su diversidad genética. En este estudio se estima la diversidad genética para A. palliata mexicana en 4 grupos en hábitat continuo y 3 en fragmentos de selva, localizados en la Reserva de la Biosfera Los Tuxtlas. Se extrajo ADN de muestras fecales y se analizaron 13 loci de microsatélites, de los cuales 8 resultaron polimórficos. Los resultados obtenidos sugieren una baja diversidad genética en este primate (Ho = 0.14, He=0.23, Na = 2.88), y una baja diferenciación genética (Fst = 0.043, p = 0.01) entre el hábitat continuo y fragmentado. No se encontraron diferencias significativas al comparar los parámetros de diversidad genética entre grupos, ni tipo de hábitat. El índice de endogamia fue positivo para cada uno de los grupos, y significativamente diferente de cero en el hábitat continuo y en los fragmentos de selva, lo cual indica una deficiencia de heterocigocidad en ambas condiciones ecológicas. Los resultados obtenidos se discuten en relación con su historia de colonización y de la fragmentación de la selva.

Abstract: INTRODUCTION: Due to the importance that Howler monkeys have on the yellow fever (YF) epidemiological sylvatic cycle in Brazil, more accurate morphological diagnostic criteria needs to be established, especially considering the differences that may exist between the genera of Brazilian non-human primates (NHPs) involved in yellow fever virus (YFV) epizootics. METHODS: Records of YF epizootics in NHPs in Brazil between 2007 and 2009 were obtained from the Brazilian Ministry of Health database to select YF positive (n=98) Howler monkeys (Alouatta sp.) for this study. The changes described in the histopathological reports were categorized by organ and their frequencies calculated. RESULTS: The most frequent lesions observed in the animals with YF were hepatocyte apoptosis (Councilman body formation), midzonal hepatocyte necrosis, steatosis, liver hemorrhage, inflammatory mononuclear cell infiltration of the liver, renal acute tubular necrosis and interstitial nephritis. Midzonal hepatocyte necrosis, steatosis and hemorrhage presented positive correlations with apoptosis of hepatocytes, suggesting strong YFV pathogenic effect association; they were also the main histopathological changes in the Alouatta sp. A pronounced negative correlation between apoptosis of hepatocytes and hepatic mononuclear cell infiltration pointed to significant histopathological differences between YFV infection in Howler monkeys and humans. CONCLUSIONS: The results warn that NHPs may exhibit different response patterns following YFV infection and require a more careful diagnosis. Presumptive diagnosis based on primate histopathological lesions may contribute to public health service control.

Species of howler monkeys (genus Alouatta) generally are parapatric. However, many areas of sympatry between different species of this genus have been recorded in recent years. We report the discovery of a new contact zone and probable hybridization between black-and-gold howler monkeys (Alouatta caraya) and brown howler monkeys (Alouatta guariba clamitans) in São Vicente do Sul, Rio Grande do Sul, Brazil (29° 46’ 07” S; 54° 47’ 53” W). We report two sightings of heterospecific groups of black-and-gold and brown howler monkeys, each composed of eight individuals, including three probable hybrids (two subadult males and one adult female). We also observed monospecific groups of phenotypically pure individuals of both species. The most plausible explanation for the occurrence of this contact zone is that brown howlers may be using the riparian forest of the Ibicuí River and its tributaries as a dispersal route towards areas of the Pampa biome, typically inhabited by black-and-gold howlers.

Las especies de monos aulladores (género Alouatta) generalmente se distribuyen de una manera parapátrica. Sin embargo, en los últimos años se han registrado muchas áreas de simpatría entre distintas especies del género. En este estudio describimos el descubrimiento de una nueva zona de contacto y la probable hibridación entre monos aulladores negros y dorados (Alouatta caraya) y monos aulladores marrones (Alouatta guariba clamitans) en São Vicente do Sul, Rio Grande do Sul, Brasil (29° 46’ 07” S; 54° 47’ 53” W). Reportamos dos avistamientos de grupos heteroespecíficos de monos aulladores negros y dorados y marrones, cada uno de estos compuesto por ocho individuos, entre ellos tres híbridos probables (dos machos subadultos y una hembra adulta). También se observaron grupos monoespecíficos con individuos fenotípicamente puros de ambas especies. La explicación más plausible para la ocurrencia de esta zona de contacto es que los aulladores marrones están utilizando las matas ribereñas del río Ibicuí y sus afluentes como una ruta de dispersión hacia zonas del bioma Pampa, típicamente habitadas por aulladores negros y dorados.