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Primates are adept at dealing with fluctuating availability of resources and display a range of responses to minimize the effects of food scarcity. An important component of primate conservation is to understand how primates adapt their foraging and ranging patterns in response to fluctuating food resources. Animals optimize resource acquisition within the home range through the selection of resource‐bearing patches and choose between contrasting foraging strategies (resource‐maximizing vs. area‐minimizing). Our study aimed to characterize the foraging strategy of a folivorous primate, Verreaux's sifaka (Propithecus verreauxi), by evaluating whether group home range size varied between peak and lean leaf seasons within a seasonally dry tropical forest in Madagascar. We hypothesized that Verreaux's sifaka used the resource maximization strategy to select high‐value resource patches so that during periods of resource depression, the home range area did not significantly change in size. We characterized resource availability (i.e., primary productivity) by season at Kirindy Mitea National Park using remotely‐sensed Enhanced Vegetation Index data. We calculated group home ranges using 10 years of focal animal sampling data collected on eight groups using both 95% and 50% kernel density estimation. We used area accumulation curves to ensure each group had an adequate number of locations to reach seasonal home range asymptotes. Neither 95% home ranges nor 50% core areas differed across peak and lean leaf resource seasons, supporting the hypothesis that Verreaux's sifaka use a resource maximization strategy. With a better understanding of animal space use strategies, managers can model anticipated changes under environmental and/or anthropogenic resource depression scenarios. These findings demonstrate the value of long‐term data for characterizing and understanding foraging and ranging patterns. We also illustrate the benefits of using satellite data for characterizing food resources for folivorous primates. Research Highlights: While seasonal leaf availability (characterized using Enhanced Vegetation Index) differed between peak and lean leaf seasons, we found no significant variation in home range and core area sizes of Verreaux's sifaka groups at Kirindy Mitea National Park, Madagascar.Our findings suggest Verreaux's sifaka use a resource‐maximizing strategy.Home range area estimates are improved when an asymptote analysis is used to ensure an adequate number of location samples and when temporal requirements are imposed to avoid concentrated sampling. [ABSTRACT FROM AUTHOR]

Simple Summary: Lemur hunting and consumption is widespread in Madagascar. Understanding what drives this phenomenon is key to conserving lemurs and protecting human livelihoods. Current research shows poverty to be a primary driver of lemur hunting and consumption, but no study has employed a composite poverty metric that includes health, education, and living standards. Our study employs such a metric, along with income, to investigate, for the first time, poverty as a driver of lemur hunting and consumption in and around Kirindy Mitea National Park, Madagascar. We document alarming levels of poverty and lemur hunting and consumption among the study community but find no relationship between the variables. Because nearly all households in the study community were impoverished, possible explanations include the following: (1) poverty is not a driver of lemur hunting and consumption in Kirindy Mitea National Park, or (2) a relationship could not be found due to the socio-economic similarity of households in our study community. We consider both interpretations in light of the current literature and offer recommendations for future research. If human and non-human primates are to continue to co-exist in and around Kirindy Mitea National Park, immediate investment in poverty eradication is required, and conservationists should test the efficacy of livestock interventions locally. The futures of human and nonhuman primates are closely tied in protected areas. Understanding this interconnectedness is especially urgent in Madagascar, one of the world's most impoverished biodiversity hotspots. Yet, no study has evaluated the relationship between poverty and lemur hunting and consumption using a composite poverty metric that includes health, education, and living standards. To address this gap, and to inform primate conservation practice and policy, we administered annual surveys to 81 households over six consecutive months (September 2018 to March 2019) in a village on the border of Kirindy Mitea National Park, Madagascar. We observed extreme deprivation scores across multiple dimensions of poverty and identified ninety-five percent of households as 'impoverished'. Of these, three-quarters (77%) of households were identified as being in 'severe poverty'. One-fifth (19%) of all households hunted lemurs and half (49%) of households consumed lemurs. While poverty eradication is an urgent need in communities around Kirindy Mitea National Park, our findings show no relationship between poverty and lemur hunting and consumption, perhaps due to the lack of variance in poverty. Our results highlight the need to investigate other contributory factors to lemur hunting and consumption locally. Because food insecurity is a known driver of lemur hunting and consumption among the study community, and because domestic meats can be preferred over protected species, we recommend testing the efficacy of livestock interventions near Kirindy Mitea National Park. [ABSTRACT FROM AUTHOR]

Primates acquire gut microbiota from conspecifics through direct social contact and shared environmental exposures. Host behaviour is a prominent force in structuring gut microbial communities, yet the extent to which group or individual‐level forces shape the long‐term dynamics of gut microbiota is poorly understood. We investigated the effects of three aspects of host sociality (social groupings, dyadic interactions, and individual dispersal between groups) on gut microbiome composition and plasticity in 58 wild Verreaux's sifaka (Propithecus verreauxi) from six social groups. Over the course of three dry seasons in a 5‐year period, the six social groups maintained distinct gut microbial signatures, with the taxonomic composition of individual communities changing in tandem among coresiding group members. Samples collected from group members during each season were more similar than samples collected from single individuals across different years. In addition, new immigrants and individuals with less stable social ties exhibited elevated rates of microbiome turnover across seasons. Our results suggest that permanent social groupings shape the changing composition of commensal and mutualistic gut microbial communities and thus may be important drivers of health and resilience in wild primate populations. [ABSTRACT FROM AUTHOR]

Sex-biased power structures are common in human and nonhuman primate societies. "Female dominance" is a term applied to a wide range of female-biased power structures. However, the full extent of this variation remains obscure because an adequate vocabulary of power has not been adopted consistently. Female power occurs throughout primates and other animals, even in male-dominant societies, but the legacy of patriarchy persists in primatologists' use of language and implicit assumptions about intersexual power. While explanations for the occurrence of female power can be accommodated within existing ethological theory, many hypotheses seeking to explain the evolution of female power are narrowly focused on particular taxa. Theories about primate social evolution would benefit from a synthesis of the disparate literature on power, increased emphasis on intersexual social relationships, and comparative studies that include the full behavioral diversity of primates and other mammals. [ABSTRACT FROM AUTHOR]

In wild primates, social behaviour influences exposure to environmentally acquired and directly transmitted microorganisms. Prior studies indicate that gut microbiota reflect pairwise social interactions among chimpanzee and baboon hosts. Here, we demonstrate that higher-order social network structure--beyond just pairwise interactions--drives gut bacterial composition in wild lemurs, which live in smaller and more cohesive groups than previously studied anthropoid species. Using 16S rRNA gene sequencing and social network analysis of grooming contacts, we estimate the relative impacts of hierarchical (i.e. multilevel) social structure, individual demographic traits, diet, scent-marking, and habitat overlap on bacteria acquisition in a wild population of Verreaux's sifaka (Propithecus verreauxi) consisting of seven social groups. We show that social group membership is clearly reflected in the microbiomes of individual sifaka, and that social groups with denser grooming networks have more homogeneous gut microbial compositions. Within social groups, adults, more gregarious individuals, and individuals that scent-mark frequently harbour the greatest microbial diversity. Thus, the community structure of wild lemurs governs symbiotic relationships by constraining transmission between hosts and partitioning environmental exposure to microorganisms. This social cultivation of mutualistic gut flora may be an evolutionary benefit of tight-knit group living. [ABSTRACT FROM AUTHOR]

Males of many group-living mammals emigrate from their social groups to improve mating opportunities. To help mitigate the social and locational costs of dispersal and to increase reproductive benefits, they may immigrate seasonally, immigrate alongside a partner, and/or replace the alpha male (versus entering a group as a subordinate). Verreaux's sifaka ( Propithecus verreauxi) are highly seasonally breeding primates characterized by male-biased dispersal. We hypothesized that (i) males time immigrations to pursue immediate mating opportunities, (ii) entrances with partners more often result in alpha male replacement, and (iii) male competitive ability affects immigration strategy and alpha male tenure length. To assess these proximate aspects of male dispersal, we examined 7 years of demographic, morphological, and behavioral data for five social groups of Verreaux's sifaka in the Kirindy Mitea National Park in western Madagascar. Contrary to expectations and studies of sifaka dispersal in other populations, we detected no strong seasonal pattern in immigrations. Immigrations occurred individually and with partners, and a trend existed for partners to increase the likelihood of replacing an alpha male. Pronounced activity of the sternal scent gland (a proxy for testosterone and prior dominance status), but not body mass, canine size, or potential correlates of leaping ability, significantly influenced immigration strategy. The absence of a seasonal immigration pattern suggests that fluid group boundaries may allow mating success without establishment in a social group before the mating season. Our results also suggest that male immigration strategies are affected by age, prior dominance status, and testosterone levels but not morphological indicators of individual competitive ability. Coalitions may be used to improve competitive ability. Finally, differences in seasonal immigration patterns and length of alpha male vacancies observed at Kirindy Mitea may be due to the relatively low population density. Am. J. Primatol. 79:e22455, 2017. © 2015 Wiley Periodicals, Inc. [ABSTRACT FROM AUTHOR]

The article focuses on a study that evaluates health, prevalence, and incidence of diseases in wild populations in Kirindy Mitea national park in Madagascar. Evaluations were performed on 33 wild Verreaux's sifaka and their blood samples and fecal samples were collected. Findings suggests differences exist between age classes for neutrophil and lymphocyte count, alkaline phosphatase, and creatinine values.

Lemur grooming has received very little attention in the literature. Nevertheless, allogrooming in lemurs has been suggested to be fundamentally different from the grooming of anthropoids. One reason is that lemurs generally rely on oral rather than manual grooming. Lemur allogrooming has also been suggested to serve less of a social function than has been attributed to anthropoid grooming. I analyzed the allogrooming behaviors of 29 Verreaux's sifaka (Propithecus verreauxi) living in five social groups in the Kirindy Forest of Madagascar. Based upon 1,586 observation hours, I found that sifaka, like anthropoids, spend very little time mutual grooming (2±3%). Half of all allogrooming involved parts of the body that could have been easily groomed by the recipient, such as the limbs. Even though ectoparasite loads are expected to be greater during the rainy season, allogrooming did not increase during the rainy season. Allogrooming rates were influenced by both rank and sex, and increased by 50–100% during the mating season. The results of this study suggest that allogrooming in Verreaux's sifaka plays an important social function, even though it is performed with a toothcomb. Am. J. Primatol. 72:254–261, 2010. © 2009 Wiley-Liss, Inc. [ABSTRACT FROM AUTHOR]

Abstract: Male Verreaux''s sifaka (Propithecus verreauxi) exhibit variation in the staining of chest hair in association with the activity of the sternal gland. Scent-marking behavior and social relationships have been shown to vary with the state of chest staining. Research on other mammals suggests that sternal gland activity is modulated by testosterone. The goal of this study was to examine the relationship among fecal testosterone, testes mass, and chest staining in sifaka. I predicted that for sifaka (1) testosterone and testes mass are positively correlated, (2) stained males have higher testosterone and larger testes than clean-chested males, (3) testes mass is greater during the mating season than the birth season, and (4) testes mass is comparable to species with multimale mating systems. Eighty fecal samples were collected from eight adult males in five social groups in the Kirindy Mitea National Park of Madagascar during the mating season and analyzed using enzyme immunoassays. Males were captured during the mating season and the subsequent birth season to measure body mass and testes size and to document chest staining. Stained males had significantly higher fT and larger testes mass than clean-chested males. Testes mass was significantly greater during the mating season than the birth season for all males. However, the stained males exhibited less testes mass reduction during birth season than clean-chested males. These results suggest that the activity of the sternal gland is regulated by testosterone and that sexual selection has shaped male morphological variation in Verreaux''s sifaka. [Copyright &y& Elsevier]

Various hypotheses to explain possible functions of scent-marking have been put forth and basically fall into five categories: territorial demarcation, ownership of resources, mate attraction, noncombative fighting, and self-advertisement. Verreaux's sifaka (Propithecus verreauxi verreauxi), like many prosimians, use scent-marking as one form of communication. The goal of this study was to determine the function of scent-marking in sifaka. All-occurrence of scent-marks, scent-mark context, and scent-mark style were collected on 23 sifaka in the Kirindy Forest of western Madagascar for 7 months (September 2001–March 2002). Scent-mark rates were collected using continuous focal animal sampling from November 2000–March 2002. Home range data were collected using monthly censuses and instantaneous focal sampling throughout the 17 months. Scent-marking behavior was exhibited almost exclusively by adults. Scent-mark rates were not related to the number of resident adult males, number of resident adult females, rank, or group size. The majority of scent-marks occurred in the perimeter of the home range; however, less than a quarter of the home range was used by only a single group. Sifaka did not preferentially mark food trees, mark during the mating season, or mark during intergroup encounters. The results from this study indicate that none of the five hypothesized functions best explains all scent-marking in Verreaux's sifaka. Rather, scent-marking may serve different functions for different individuals. Am. J. Primatol. 68:622–636, 2006. © 2006 Wiley-Liss, Inc. [ABSTRACT FROM AUTHOR]