Group Of Baboons Research Articles

High early lactational synchrony within baboon groups predicts increased infant mortality.

Social group composition can have fitness implications for group members by determining opportunities for affiliative and competitive interactions. Female-female competition may be particularly acute when many groupmates have young infants at the same time, with potential consequences for infant survival. Here, we used decades of data on wild baboons (Papio sp.) in Amboseli, Kenya, to examine the effects of 'early lactational synchrony' (here, the proportion of females in a group with an infant <90 days old) on female-female agonistic interactions and infant survival. Because early lactation is an energetically demanding time for mothers and a risky time for infants, we expected early lactational synchrony to produce intensified competition for food and/or male protectors, resulting in more frequent female-female agonistic interactions and high infant mortality. In support of these predictions, we found that the frequency of female-female agonistic interactions increased with increasing early lactational synchrony. Reproductive state affected this relationship: while females in all states (cycling, pregnant, and postpartum amenorrhea) initiated more agonistic interactions when early lactational synchrony was high, only females in postpartum amenorrhea (including, but not limited to, females in early lactation) received more agonistic interactions. Furthermore, while high early lactational synchrony was rare, it strongly predicted infant mortality. This association may result from both aggression among adult females and infanticidal behavior by peripubertal females. These findings provide novel evidence that social dynamics may shape reproductive phenology in a nonseasonal breeder. Specifically, both competition among reproductive females and harassment from nonreproductive females may select against synchronous reproduction.

Estimating individual exposure to predation risk in group-living baboons, Papio anubis.

In environments with multiple predators, vulnerabilities associated with the spatial positions of group-living prey are non-uniform and depend on the hunting styles of the predators. Theoretically, coursing predators follow their prey over long distances and attack open areas, exposing individuals at the edge of the group to predation risk more than those at the center (marginal predation). In contrast, ambush predators lurk unnoticed by their prey and appear randomly anywhere in the group; therefore, isolated individuals in the group would be more vulnerable to predators. These positions of vulnerability to predation are expected to be taken by larger-bodied males. Moreover, dominant males presumably occupy the center of the safe group. However, identifying individuals at higher predation risk requires both simultaneous recording of predator location and direct observation of predation events; empirical observations leave ambiguity as to who is at risk. Instead, several theoretical methods (predation risk proxies) have been proposed to assess predation risk: (1) the size of the individual 'unlimited domain of danger' based on Voronoi tessellation, (2) the size of the 'limited domain of danger' based on predator detection distance, (3) peripheral/center position in the group (minimum convex polygon), (4) the number and direction of others in the vicinity (surroundedness), and (5) dyadic distances. We explored the age-sex distribution of individuals in at-risk positions within a wild baboon group facing predation risk from leopards, lions, and hyenas, using Global Positioning System collars. Our analysis of the location data from 26 baboons revealed that adult males were consistently isolated at the edge of the group in all predation risk proxies. Empirical evidence from previous studies indicates that adult male baboons are the most frequently preyed upon, and our results highlights the importance of spatial positioning in this.

Potential Hotspots of Hamadryas Baboon–Human Conflict in Al-Baha Region, Saudi Arabia

In recent decades, conflicts between hamadryas baboons (Papio hamadryas) and the rapidly growing human population in the mountainous areas of Western, Southwestern, and Southern Saudi Arabia have accelerated. This conflict, historically occurring mainly between farmers and baboons, has now moved to the urbanized areas in the baboon range and is mainly caused by the common use of spatial and other resources by baboons and humans. The goal of this study was to describe the spatial distribution of baboon groups and to estimate the population size of baboons in the Al-Baha region. The results indicate that baboons are present in all administrative areas of the Al-Baha region with a concentration along the mountain chain running from northwest to southeast and the western part of the region. As expected, rubbish dumps constitute baboon hotspots due to the large amounts of human-derived food. However, the baboons also travel into towns for foraging. The prevention of baboon accessibility to human-derived food would be an important step to reduce causes of conflicts between humans and baboons.

Confessions of a baboon watcher: from inside to outside the paradigm

In this “tale” I summarize the major landmarks of my 50-year career watching wild olive baboons (Papio anubis). I review some major discoveries, like baboon hunting and baboon social strategies of competition and defense, that only a creature with a “mind” could manage. My efforts expanded beyond science to include community-based conservation because quite early on these baboons experienced many of the threats of the Anthropocene. My research expanded to include studying crop-raiding by naïve groups of baboons, the first scientific translocation of a primate species, and a detour to study the invasion of a non-indigenous cactus, Opuntia stricta. Throughout I worked with local communities to find solutions to problems that the baboons created, and also to develop new options for their livelihoods. As the baboon research became a long-term project, it depended on a team of Kenyan research assistants who made possible the simultaneous monitoring of up to six baboon troops as well as extensive ecological monitoring. Knowing the ecology, including the impact of the sedentarization of pastoralists in the area, meant we could interpret the process of invasion by a non-indigenous cactus for the first time. Ecological periods allowed comparisons of the same troop over time and different baboon groups during the same ecological phase. Although I began my work before hypothesis testing was the preferred approach, once the paradigm changed, I continued to study and learn what matters to baboons from their perspective. As a result of observing them for 50 years, the baboons showed me that evolution often does not work the way that I had been taught, and it took all my detours and studies to convince me that anecdotes, when they are systematic and comparative, are not stories to be discounted, but evidence, much like Darwin’s natural history. Natural history can reassemble the pieces that quantitative hypothesis testing has teased apart to provide its larger meaning. Today, the lone scientist, like me, is an anachronism because no one person has expertise in the many fields needed to understand and save the primates we care about.

Patterns of predation and meat-eating by chacma baboons in an Afromontane environment

Abstract Meat-eating among non-human primates has been well documented but its prevalence among Afromontane baboons is understudied. In this study we report the predatory and meat-eating behaviours of a habituated group of gray-footed chacma baboons (Papio ursinus griseipes) living in an Afromontane environment in South Africa. We calculated a vertebrate-eating rate of 1 every 78.5 hours, increasing to 58.1 hours when unsuccessful predation attempts were included. A key food source was young antelopes, particularly bushbuck (Tragelaphus scriptus), which were consumed once every 115 observation hours. Similar to other baboon research sites, predations seemed mostly opportunistic, adult males regularly scrounged and monopolised prey, there was no evidence they used an active kill bite, and active sharing was absent. This is the first baboon study to report predation of rock python (Python sebae) eggs and likely scavenging of a leopard (Panthera pardus) kill (bushbuck) cached in a tree. We also describe several scramble kleptoparasitism events, tolerating active defence from antelope parents, and the baboons inhibiting public information about predations. In the latter case, baboons with meat often hid beyond the periphery of the group, reducing the likelihood of scrounging by competitors. This often led to prey carcasses being discarded without being fully exploited and potentially providing resources to scavengers. We also highlight the absence of encounters with numerous species, suggesting the baboons are a key component of several species’ landscapes of fear. Given these findings it seems likely that their ecological role in the Soutpansberg has been undervalued, and such conclusions may also hold for other baboon populations.

Intolerant baboons avoid observer proximity, creating biased inter-individual association patterns

Social network analysis is an increasingly popular tool for behavioural ecologists exploring the social organisation of animal populations. Such analyses require data on inter-individual association patterns, which in wild populations are often collected using direct observations of habituated animals. This assumes observers have no influence on animal behaviour; however, our previous work showed that individuals in a habituated group of chacma baboons (Papio ursinus griseipes) displayed consistent and individually distinct responses to observer approaches. We explored the implications of our previous findings by measuring the inter-individual association patterns of the same group of chacma baboons at different observer distances. We found a strong positive association between individual tolerance levels (towards observers) and how often an animal appeared as a neighbour to focal animals when observers were nearer, and a neutral relationship between the same variables when the observer was further away. Additionally, association matrices constructed from different observation distances were not comparable within any proximity buffer, and neither were the individual network metrics generated from these matrices. This appears to be the first empirical evidence that observer presence and behaviour can influence the association patterns of habituated animals and thus have potentially significant impacts on measured social networks.

Ecological and social pressures interfere with homeostatic sleep regulation in the wild.

Sleep is fundamental to the health and fitness of all animals. The physiological importance of sleep is underscored by the central role of homeostasis in determining sleep investment - following periods of sleep deprivation, individuals experience longer and more intense sleep bouts. Yet, most sleep research has been conducted in highly controlled settings, removed from evolutionarily relevant contexts that may hinder the maintenance of sleep homeostasis. Using triaxial accelerometry and GPS to track the sleep patterns of a group of wild baboons (Papio anubis), we found that ecological and social pressures indeed interfere with homeostatic sleep regulation. Baboons sacrificed time spent sleeping when in less familiar locations and when sleeping in proximity to more group-mates, regardless of how long they had slept the prior night or how much they had physically exerted themselves the preceding day. Further, they did not appear to compensate for lost sleep via more intense sleep bouts. We found that the collective dynamics characteristic of social animal groups persist into the sleep period, as baboons exhibited synchronized patterns of waking throughout the night, particularly with nearby group-mates. Thus, for animals whose fitness depends critically on avoiding predation and developing social relationships, maintaining sleep homeostasis may be only secondary to remaining vigilant when sleeping in risky habitats and interacting with group-mates during the night. Our results highlight the importance of studying sleep in ecologically relevant contexts, where the adaptive function of sleep patterns directly reflects the complex trade-offs that have guided its evolution.

Female post-copulatory behavior in a group of olive baboons (Papio anubis) infected by Treponema pallidum.

Pathogens exert a profound and pervasive cost on various aspects of primate sociality and reproduction. In olive baboons (Papio anubis) at Lake Manyara National Park, Tanzania, genital skin ulcers, caused by the bacterium Treponema pallidum subsp. pertenue, are associated with increased female mating avoidance and altered male mating patterns at a pre-copulatory and copulatory level. Beyond this, mating is also comprised of post-copulatory interactions among sexual partners (i.e., copulation calls, darting [post-copulatory sprint away from the male], and post-copulatory grooming). In baboons, female post-copulatory behavior is hypothesized to incite male-male competition, promote subsequent copulations, and/or strengthen the bonds between the mating pairs. Due to a higher reproductive burden (i.e. pregnancy, lactation, infant rearing), females should avoid proceptive behavior after mating to decrease further exposure to potential pathogens. To investigate whether the presence of genital skin ulcers has an impact at the post-copulatory level, we analyzed 517 copulation events of 33 cycling females and 29 males with and without genital skin ulcers. The occurrence of female post-copulatory behaviors was not altered by genital skin ulcerations in males. Similar to other baboon populations, females in our study group were more likely to utter copulation calls after an ejaculatory copulation. The likelihood of darting was higher after ejaculatory copulations and with the presence of copulation calls. Post-copulatory grooming (i.e., occurring within 15 seconds after a copulation) was not frequently observed. Our results indicate that despite the presence of conspicuous signs of disease, female post-copulatory behavior was not affected by the genital health status of the males. This indicates that in our study group, infection cues caused by T. pallidum subsp. pertenue play a major role before and during mating, but not after mating. The post-copulatory behavior of females is most likely affected by physiological or evolutionary constraints other than sexually transmitted infections.

Gastrointestinal parasites of baboons (Papio papio) in Niokolo-Koba National Park, Senegal.

Background:Primates can harbor parasites that could be pathogenic or not for humans and primates themselves. It is necessary to know the parasitological situation of the primates that are under surveillance in the park.Aim:To estimate the prevalence and diversity of gastrointestinal parasites, including zoonotic potential parasites, in baboons in the Niokolo-Koba National Park located in Senegal.Method:Fecal samples (n = 50) from two groups of baboons (A and B) were collected in October 2019. The samples were processed using the flotation technique and the modified Ritchie method. Slides were examined microscopically and the parasite identification was based on morphology, color, and parasite content.Results:A total of seven nematodes (Strongyloides sp., Trichirus sp., Ancylostoma sp., Mammo monogamus, Enterobius sp., Strongyloides stercoralis, Strongyle digestif), one cestode (Bertiella sp.), and one trematode (Fasciolopsis sp.) were identified. The overall prevalence was 78%, while the prevalence of poly-infected samples was 49%. The parasite with zoonotic potential, S. stercoralis, was identified in group B samples. Trichuris sp., which is common and pathogenic to humans and primates, was present with prevalence of 52% and of 32% in groups A and B, respectively.Conclusion:These results suggest that baboons are infested with zoonotic parasites and this situation could expose people working in this park to infection. Contact between humans and these baboons or their feces could expose them to infection with zoonotic parasites.

Study the Differences between the Parameters of Learning and Exploratory Activities in Adult Male Rhesus Monkeys (Macaca mulatta) and Baboon Hamadryas (Papio hamadryas).

We studied exploratory activity and learning ability in sexually mature male rhesus monkeys (Macaca mulatta) and hamadryas baboons (Papio hamadryas). The interspecies differences were analyzed by the following parameters: the level of exploratory activity, diversity of exploratory activity, concentration on the object, learning ability, training levels, and dynamics of learning. The studied group of hamadryas baboons showed higher levels of exploratory activity and learning ability than the group of rhesus monkeys.

Gut microbiome and metabolome in a non-human primate model of chronic excessive alcohol drinking

A relationship between the gut microbiome and alcohol use disorder has been suggested. Excessive alcohol use produces changes in the fecal microbiome and metabolome in both rodents and humans. Yet, these changes can be observed only in a subgroup of the studied populations, and reversal does not always occur after abstinence. We aimed to analyze fecal microbial composition and function in a translationally relevant baboon model of chronic heavy drinking that also meets binge criteria (drinking too much, too fast, and too often), i.e., alcohol ~1 g/kg and blood alcohol levels (BALs) ≥ 0.08 g/dL in a 2-hour period, daily, for years. We compared three groups of male baboons (Papio anubis): L = Long-term alcohol drinking group (12.1 years); S = Short-term alcohol drinking group (2.7 years); and C = Control group, drinking a non-alcoholic reinforcer (Tang®) (8.2 years). Fecal collection took place during 3 days of Drinking (D), followed by a short period (3 days) of Abstinence (A). Fecal microbial alpha- and beta-diversity were significantly lower in L vs. S and C (p’s < 0.05). Members of the commensal families Lachnospiraceae and Prevotellaceae showed a relative decrease, whereas the opportunistic pathogen Streptococcus genus showed a relative increase in L vs. S and C (p’s < 0.05). Microbiota-related metabolites of aromatic amino acids, tricarboxylic acid cycle, and pentose increased in L vs. S and C (FDR-corrected p < 0.01), with the latter two suggesting high energy metabolism and enhanced glycolysis in the gut lumen in response to alcohol. Consistent with the long-term alcohol exposure, mucosal damage and oxidative stress markers (N-acetylated amino acids, 2-hydroxybutyrate, and metabolites of the methionine cycle) increased in L vs. S and C (FDR-corrected p < 0.01). Overall, S showed few differences vs. C, possibly due to the long-term, chronic alcohol exposure needed to alter the normal gut microbiota. In the three groups, the fecal microbiome barely differed between conditions D and A, whereas the metabolome shifted in the transition from condition D to A. In conclusion, changes in the fecal microbiome and metabolome occur after significant long-term excessive drinking and are only partially affected by acute forced abstinence from alcohol. These results provide novel information on the relationship between the fecal microbiome and metabolome in a controlled experimental setting and using a unique non-human primate model of chronic excessive alcohol drinking.

Socioecology Explains Individual Variation in Urban Space Use in Response to Management in Cape Chacma Baboons (Papio ursinus)

The presence of wildlife adjacent to and within urban spaces is a growing phenomenon globally. When wildlife’s presence in urban spaces has negative impacts for people and wildlife, nonlethal and lethal interventions on animals invariably result. Recent evidence suggests that individuals in wild animal populations vary in both their propensity to use urban space and their response to nonlethal management methods. Understanding such interindividual differences and the drivers of urban space use could help inform management strategies. We use direct observation and high-resolution GPS (1 Hz) to track the space use of 13 adult individuals in a group of chacma baboons (Papio ursinus) living at the urban edge in Cape Town, South Africa. The group is managed by a dedicated team of field rangers, who use aversive conditioning to reduce the time spent by the group in urban spaces. Adult males are larger, more assertive, and more inclined to enter houses, and as such are disproportionately subject to “last resort” lethal management. Field rangers therefore focus efforts on curbing the movements of adult males, which, together with high-ranking females and their offspring, comprise the bulk of the group. However, our results reveal that this focus allows low-ranking, socially peripheral female baboons greater access to urban spaces. We suggest that movement of these females into urban spaces, alone or in small groups, is an adaptive response to management interventions, especially given that they have no natural predators. These results highlight the importance of conducting behavioral studies in conjunction with wildlife management, to ensure effective mitigation techniques.

The effects of alpha male removal on the social behavior of a group of olive baboons (Papio anubis)

ABSTRACT In captivity, the managers of primate populations have removed individuals from their groups for medical and social reasons, but there has been little documentation regarding the consequences of this extraction on the sociality of the remaining individuals. This study provides information about the social effect of the alpha male removal in a group of olive baboons (Papio anubis) maintained at the Station of Primatology of CNRS (France). Data on social behavior was collected before and after male removal and then compared. Moreover, this social information was used to calculate the individual dominance index and the group dominance ranking. Overall, our results indicate that females seem to respond to male removal showing a more affiliative and tolerant behavior. However, the results also highlight the different coping mechanisms of females with this new social context. Therefore, this information could be useful for managers of primate populations, allowing them to anticipate the response of captive groups when facing certain sociodemographic changes. In this regard, we recommended creating a detailed procedure before the removal of the individuals that considers the characteristics of the individuals.

Costs of seasonality at a southern latitude: Behavioral endocrinology of female baboons in the Cape Peninsula of South Africa

Environmental challenges in the form of temperature extremes and unusual precipitation, which may lead to prolonged periods outside the thermoneutral zone, can be detrimental to animal physiology. Chacma baboons in the Cape Peninsula of South Africa, one of the highest latitudes at which nonhuman primates are found, experience extremes of both temperature and rainfall, as well as seasonal differences in day length that require animals to condense their daily routine into dramatically reduced daylight hours. Here we examine the effects of these climatic factors on the behavior (activity budgets and foraging patterns) and physiology (fecal glucocorticoid concentrations) of adult females (N = 33) in three groups of chacma baboons (Papio ursinus) inhabiting the Cape Peninsula, where temperatures ranged from 7 to 39 °C, monthly rainfall ranged from 2 to 158 mm, and day length varied by 4.5 h across seasons. Climatic variables showed a clear relationship to female baboon glucocorticoid concentrations, which significantly increased with lower temperatures, higher rainfall and shorter day lengths. Activity budgets also differed between summer and winter, with females generally spending less time socializing, moving and resting in the winter compared to summer, with some differences between troops in their feeding-related activities. Cold temperatures accompanied by rainfall and short day lengths may thus represent an ecological constraint for this population. This study highlights the potential impact of anthropogenic climate change on the physiology, behavior, and, ultimately, survival of wildlife populations.

Activity time budgets of ecologically relaxed groups of geladas (Theropithecus gelada) and mandrills (Mandrillus sphinx): what happens when time is no longer a constraint?

Primates spend their daytime engaged in four non-overlapping, time-consuming, biologically relevant activities, namely, feeding, moving, resting, and socializing. The present study addressed two issues relevant to socio-ecological theory and life-history theory: how do individuals re-schedule the time allocated to these activity categories when they live in ecologically relaxed settings, where they are food-provisioned, live under benign weather conditions, and are predator-free? How do individuals trade the different activity categories against each other in a relatively time constraint-free setting? We predicted that feeding and moving times should decrease and resting and socializing times should increase. We also explored the relation of feeding time to resting time and social time to see which activity category is more dispensable when feeding time increases. Here we analyzed the activity time budgets of a group of geladas, Theropithecus gelada, and a group of mandrills, Mandrillus sphinx, housed in captivity in similarly vegetated and large-sized enclosures, and exposed to identical temperate-zone climate conditions, and compared them to time budget data available for wild groups of geladas and baboons. We found that they displayed activity budgets that largely matched those reported for wild groups of geladas and baboons, except moving time that decreased, but in geladas solely. We also found a tighter negative relation of feeding to resting time than to social time. These findings indicate that freeing individuals in a captive setting from the time constraints and pressing demands faced by their wild counterparts does not necessarily cause a significant re-scheduling of their activity time budgets. They also support the “social glue” hypothesis, as an increase of feeding time is associated with a significant decrease in resting, not social, time. The notion of a captivity-typical versus wild-typical profile of activity time budgets appears unsupported given the remarkable overlapping of time budget scores across settings and the huge inter-populational, intergroup, and intragroup variation reported.

Synthetic Pentasaccharide Fondaparinux (Arixtra®) Reduces Sepsis Induced Coagulopathy and Promotes Survival in the Baboon Model of E. coli Sepsis

Bacterial sepsis triggers profound dysfunction of the coagulation and fibrinolytic systems leading to disseminated intravascular coagulation (DIC), characterized by consumptive coagulopathy and bleeding. DIC may contribute to multiple organ failures due to occlusion of microvasculature and tissue hypoperfusion. Bacteria and/or bacteria-derived molecules initiate the activation of both the intrinsic/contact phase and extrinsic pathways of coagulation that activate factor X (FX). Active FX (FXa) is the enzyme of the prothrombinase complex that leads to thrombin generation and subsequent formation of fibrin clots. Arixtra® (Fondaparinux Sodium), a synthetic pentasaccharide, binds to antithrombin and thereby selectively inhibits FXa. Here, a baboon model of E. coli sepsis was used to investigate the effect of FXa inhibition on sepsis-induced activation of coagulation and fibrinolytic pathways.Two experimental baboon groups were studied:(i) E. coli challenge (n=4) , (ii) E. coli + Arixtra®(n=4). E. coli (1-2 x 1010 CFU/kg, LD100 dose) was infused intravenously over a 2 hour period. Arixtra® (0.08mg/kg) was administered subcutaneously to achive therapeutic concentration at the time of E. coli challenge (T0). The activation of coagulation was studied by measuring plasma levels of inhibitory complexes of antithrombin (AT) with activated factors: FXa-AT, FXIa-AT, thrombin-AT (TAT) and FVIIa-AT.E. coli challenge induced the activation of coagulation pathway as early as 2 hours post-challenge as evident by increase in plasma level of FXa-AT and TAT complexes. Contact pathway activation (FXIa-AT), as well as FVII activation (FVIIa-AT), were significantly reduced in Arixtra® treated animals. FXa-AT and TAT complexes were maximally present at 4-8 hours post-challenge and were reduced by more than 50% in Arixtra® treated animals (Fig. 1, A and B). Similarly, Arixtra® reduced activated partial thromboplastin time and prothrombin time as well as fibrinogen consumption following E. coli challenge. In line with the above observation, the plasma levels of fibrinolysis markers, fibrinogen/fibrin degradation products, D-Dimer and plasmin-antiplasmin complex (PAP) were significantly reduced in the Arixtra® treated group (Fig. 1, C and D). Platelets consumption/thrombocytopenia was similar in both the Arixtra® treated and the untreated groups. Moreover, neutrophil activation as measured by myeloperoxidase activity in plasma was reduced in the Arixtra® treated group. Two out of four animals survived in Arixtra® treated groups compared to 100% mortality in untreated group [Log-rank (Mantel-Cox) test P=0.0037]. Notably, Arixtra® treated non-survivor animals demonstrated prolonged survival times.Overall, the data suggests that Arixtra® reduced both coagulation and fibrinolytic pathway activation, thereby preventing DIC and providing survival benefits in E. coli sepsis. [Display omitted] DisclosuresNo relevant conflicts of interest to declare.

The utility of social network analysis for informing zoo management: Changing network dynamics of a group of captive hamadryas baboons (Papio hamadryas) following an introduction of two young males.

Comprehensive knowledge of social groups within zoos allows for better understanding of the issues surrounding group stability and how to provide captive animals with optimal care. A developing area of sociality research that works to improve this understanding is social network analysis (SNA), which allows scientists to apply quantitative measures of group systems to represent social structure. In December 2015, Oakland Zoo introduced two new males to the hamadryas baboon (Papio hamadryas) exhibit. We examined the changing group structure of these baboons over the course of 6 months (July-December 2016) using social network analysis, specifically focusing on the changing social structure of the existing group and the utility of SNA methods for optimal care of captive animals. This study found that over time, the new males decreased their overall individual centrality, while some individuals had an increase in betweenness, a measure of an individual's intermediary role in the network. The results also illustrate the utility of social network analysis as tool for zoo management to examine how husbandry may have an impact on their animals, specifically for social species. Further research on the social networks of hamadryas baboon multi-clan formation could provide more information about the societal structure of this primate species, as well as the use of social network analysis as a valuable tool in captive animal management.

Computerized assessment of dominance hierarchy in baboons (Papio papio).

Dominance hierarchies are an important aspect of Primate social life, and there is an increasing need to develop new systems to collect social information automatically. The main goal of this research was to explore the possibility to infer the dominance hierarchy of a group of Guinea baboons (Papio papio) from the analysis of their spontaneous interactions with freely accessible automated learning devices for monkeys (ALDM, Fagot & Bonté Behavior Research Methods, 42, 507-516, 2010). Experiment 1 compared the dominance hierarchy obtained from conventional observations of agonistic behaviours to the one inferred from the analysis of automatically recorded supplanting behaviours within the ALDM workstations. The comparison, applied to three different datasets, shows that the dominance hierarchies obtained with the two methods are highly congruent (all rs ≥ 0.75). Experiment 2 investigated the experimental potential of inferring dominance hierarchy from ALDM testing. ALDM data previously published in Goujon and Fagot (Behavioural Brain Research, 247, 101-109, 2013) were re-analysed for that purpose. Results indicate that supplanting events within the workstations lead to a transient improvement of cognitive performance for the baboon supplanting its partners and that this improvement depends on the difference in rank between the two baboons. This study therefore opens new perspectives for cognitive studies conducted in a social context.

Effects of Chronic Viral Infection on Lymphocyte Populations in Middle-aged Baboons (Papio anubis).

Aging of the immune system is characterized by the loss of naïve T-cells, increased inflammation, and immune function impairment. Chronic infection with cytomegalovirus is thought to play a role in age-related changes in immunity. Therefore, to assess the effect of pathogens such as cytomegalovirus on the immune system, we determined lymphocyte populations and inflammatory markers over a 3-y period in captive, middle-age baboons, with various exposure to pathogens and shedding pressure. Groups included SPF (i.e., pathogen-negative; n = 14); large-group, conventionally housed (CONV LG; pathogen- positive; n = 14), and small-group, conventionally housed (CONV SM; pathogen-positive; n = 7). All baboon groups showed a decrease in CD45RA+ CD28+ (i.e., naive) cells over time during middle age, but the rate of decline appeared faster in CONV LG baboons than in the other groups. In addition, the reduction in CD45RA+ CD28+ cells in the CONV LG baboons coincided with higher IgG levels against baboon cytomegalovirus, increased serum cortisol concentration, and a greater inflammatory phenotype. The results of this project support a role for cytomegalovirus infection in immune system alterations in middle-aged baboons.

Insights into short- and long-term crop-foraging strategies in a chacma baboon (Papio ursinus) from GPS and accelerometer data.

Crop‐foraging by animals is a leading cause of human–wildlife “conflict” globally, affecting farmers and resulting in the death of many animals in retaliation, including primates. Despite significant research into crop‐foraging by primates, relatively little is understood about the behavior and movements of primates in and around crop fields, largely due to the limitations of traditional observational methods. Crop‐foraging by primates in large‐scale agriculture has also received little attention. We used GPS and accelerometer bio‐loggers, along with environmental data, to gain an understanding of the spatial and temporal patterns of activity for a female in a crop‐foraging baboon group in and around commercial farms in South Africa over one year. Crop fields were avoided for most of the year, suggesting that fields are perceived as a high‐risk habitat. When field visits did occur, this was generally when plant primary productivity was low, suggesting that crops were a “fallback food”. All recorded field visits were at or before 15:00. Activity was significantly higher in crop fields than in the landscape in general, evidence that crop‐foraging is an energetically costly strategy and that fields are perceived as a risky habitat. In contrast, activity was significantly lower within 100 m of the field edge than in the rest of the landscape, suggesting that baboons wait near the field edge to assess risks before crop‐foraging. Together, this understanding of the spatiotemporal dynamics of crop‐foraging can help to inform crop protection strategies and reduce conflict between humans and baboons in South Africa.