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African wolves (Canis lupaster) and Ethiopian wolves (C. simensis) occur often sympatrically across habitats in the Ethiopian Highlands, with recent studies finding evidence for interspecific competition. However, unlike the well-studied Ethiopian wolf, comparatively little is known about the ecology of the African wolf in the Ethiopian Highlands. To address this empirical gap, we collected data on home range size, habitat use, and activity patterns of radio-collared African wolves at the Guassa Menz Community Conservation Area (GCCA) and Borena Saynt Worehimenu National Park (BSNP). We followed the African wolves (5 in GCCA, 6 in BSNP) for 16 months and had 659 ± 83 encounters with each individual. The mean 95% kernel density estimate home range size of African wolves was higher in BSNP (4.5 ± 1.5 km2) than at GCCA (2.2 ± 0.7 km2). In 55% (n = 3934) of the encounters the wolves were found to be solitary, whereas in other encounters we found them in groups of two to seven. At both sites, the African wolves were more often found in areas close to human settlements than in more intact habitat, and they were mainly active at dawn and dusk. These results show flexibility in African wolf socioecology in response to habitat fragmentation and anthropogenic disturbance. We recommend further studies on major causes of spatial and temporal niche partitioning of Ethiopian wolves and African wolves in the Ethiopian Highlands.

Ethiopia is home to one of the richest and most unique assemblages of fauna and flora on the African continent. Contained within its borders are two major centers of endemism, the mesic Roof of Africa (also known as the Ethiopian Highlands) and the arid Horn of Africa, resulting from the country’s varied topography and consequent geographic isolation. These centers of endemism are crucial to global conservation as evidenced by their classification within the Eastern Afromontane and Horn of Africa biodiversity hotspots, respectively. Ethiopia’s diverse ecosystems and the biodiversity they contain are increasingly threatened by climate change and the growing impacts of Africa’s second largest human and largest livestock populations. In this paper, we focus on several key areas of recent and ongoing research on Ethiopian biodiversity that have broadened our understanding of nature and its conservation in Africa. Topics explored include the behavioral ecology of Ethiopia’s large social mammals, the ecology and conservation of its unique coffee forests, and Ethiopian approaches to community conservation, fortress conservation, and nature-based solutions. We also highlight the increasing prominence of Ethiopian scientists in studies of the country’s biodiversity in recent decades. We suggest promising avenues for future research in evolutionary biology, ecology, systematics, and conservation in Ethiopia and discuss how recent and ongoing work in Ethiopia is helping us better understand and conserve nature in the human-dominated landscapes of Africa and other tropical regions today.

Although selecting advantageous sleeping sites is crucial for nonhuman primates, the extent to which different factors contribute to their selection remains largely unknown for many species. We investigated hypotheses relating to predator avoidance, food access, and thermoregulation to explain the sleeping behavior of Bale monkeys (Chlorocebus djamdjamensis) occupying a degraded fragmented forest, Kokosa, in the southern Ethiopian Highlands. We found that the study group reused 11 out of 20 sleeping sites used during the 42 study days over a 6-month period. Sleeping sites were usually close to the last feeding trees of the day (mean distance =15.2 m) and/or the first feeding trees of the next morning (mean distance = 13.5 m). This may reflect an attempt to maximize feeding efficiency and reduce travel costs. Compared to the mean trees in the study area, sleeping trees were significantly shorter. Bale monkeys selected sleeping places in trees with high foliage density above and below them, lending support to the hypothesis that they select sleeping places that can conceal them from predators and at the same time offer shelter from cold weather. The monkeys also frequently huddled at night. Our results suggest that predator avoidance, access to food resources, and thermoregulation all likely influence the selection of sleeping sites by Bale monkeys.

Neopterin, a product of activated white blood cells, is a marker of nonspecific inflammation that can capture variation in immune investment or disease-related immune activity and can be collected noninvasively in urine. Mounting studies in wildlife point to lifetime patterns in neopterin related to immune development, aging, and certain diseases, but rarely are studies able to assess whether neopterin can capture multiple concurrent dimensions of health and disease in a single system. We assessed the relationship between urinary neopterin stored on filter paper and multiple metrics of health and disease in wild geladas (Theropithecus gelada), primates endemic to the Ethiopian highlands. We tested whether neopterin captures age-related variation in inflammation arising from developing immunity in infancy and chronic inflammation in old age, inflammation related to intramuscular tapeworm infection, helminth-induced anti-inflammatory immunomodulation, and perturbations in the gastrointestinal microbiome. We found that neopterin had a U-shaped relationship with age, no association with larval tapeworm infection, a negative relationship with metrics related to gastrointestinal helminth infection, and a negative relationship with microbial diversity. Together with growing research on neopterin and specific diseases, our results demonstrate that urinary neopterin can be a powerful tool for assessing multiple dimensions of health and disease in wildlife.

Following the introduction of DNA fingerprinting in the 1980s, studies have repeatedly revealed mismatches between the mating system inferred from social behaviour and the mating system revealed through genetic relationships. In this study, we examined the occurrence of extragroup paternities (EGPs) in gelada monkeys at Guassa, Ethiopia and explored how EGPs may be acquired in this species, which is conventionally considered to have a single breeding male (‘leader’) per social group (‘unit’). We found that while leaders sired most offspring, a substantial proportion (17 of 88 offspring, 19%) were sired by extra-unit males. Offspring were more likely to be sired by extra-unit males when they were: (1) conceived in the 6 months following the start of peak rainfall (July–December) and (2) the first successful conception for a mother. Furthermore, eight of the 17 extra-unit paternities were directly or indirectly the result of a single infertile leader, indicating that infertility plays an important role in the occurrence of EGPs. Compiling published data revealed that the 19% EGP rate observed among Guassa geladas was also the median for polygynous nonhuman primates (range 0–57%, N = 5 populations), in contrast to geladas in the Simien Mountains, where EGPs are absent or rare. Thus, intraspecific variation in EGP rates in geladas encompasses much of the range described across polygynous primates more broadly. The Guassa gelada EGP rate was similar to the median rate reported for mammals. Primates generally had a lower median rate of EGPs, more similar to the median rate reported for birds. Understanding variation in EGP rates requires understanding the outcomes of competing interests of males and females within the same species, as well as how these features contribute to the evolution of social systems and influence variation in EGP rates at higher taxonomic levels.

Objectives: Although fermented food use is ubiquitous in humans, the ecological and evolutionary factors contributing to its emergence are unclear. Here we investigated the ecological contexts surrounding the consumption of fruits in the late stages of fermentation by wild primates to provide insight into its adaptive function. We hypothesized that climate, socioecological traits, and habitat patch size would influence the occurrence of this behavior due to effects on the environmental prevalence of late-stage fermented foods, the ability of primates to detect them, and potential nutritional benefits. Materials and methods: We compiled data from field studies lasting at least 9 months to describe the contexts in which primates were observed consuming fruits in the late stages of fermentation. Using generalized linear mixed-effects models, we assessed the effects of 18 predictor variables on the occurrence of fermented food use in primates. Results: Late-stage fermented foods were consumed by a wide taxonomic breadth of primates. However, they generally made up 0.01%–3% of the annual diet and were limited to a subset of fruit species, many of which are reported to have mechanical and chemical defenses against herbivores when not fermented. Additionally, latestage fermented food consumption was best predicted by climate and habitat patch size. It was more likely to occur in larger habitat patches with lower annual mean rainfall and higher annual mean maximum temperatures. Discussion: We posit that primates capitalize on the natural fermentation of some fruits as part of a nutritional strategy to maximize periods of fruit exploitation and/or access a wider range of plant species. We speculate that these factors contributed to the evolutionary emergence of the human propensity for fermented foods. Canadian Institute for Advanced Research/[]/CIFAR/Canadá UCR::Vicerrectoría de Docencia::Ciencias Básicas::Facultad de Ciencias::Escuela de Biología

Dietary responses to the habitat heterogeneity resulting from anthropogenic disturbance vary among primates. Some species alter their foraging strategy and continue to thrive in human-modified habitats while others are unable to modify their diets sufficiently to cope with such disturbance. Over a 12-mo period, we investigated the feeding ecology of the Omo River guereza (Colobus guereza guereza), a subspecies of black-and-white colobus monkeys endemic to Ethiopia, in a large continuous forest (Munessa: LC group), a smaller modified continuous forest (Wondo Genet: SC group), and a tiny forest fragment (Aregash: F group). We found that the forest fragment had higher tree stem densities but lower overall tree basal area than the continuous forests. In all three forests, guerezas were mostly folivorous (LC group: 83%; SC group: 65%; F group: 62%) and consumed young leaves in accordance with their availability. However, in addition to these broad dietary similarities, there were several differences between forests suggesting strategies guerezas may use to cope with habitat heterogeneity in southern Ethiopia. We found that guerezas in anthropogenically altered forests relied less on mature leaves and more on whole fruits (F group) or flowers (SC group) than guerezas in large continuous forest (LC group). Guerezas also devoted large percentages of their feeding time to exotic species in disturbed forests (SC group: 49.0%; F group: 20.6%) but not in the large continuous forest (LC group: 0.0%). Lastly, guerezas in disturbed forests had richer diets (F group, N = 37 species, SC group, N = 32) than those in the large continuous forest (LC group, N = 27). Thus, our study found that within the folivorous dietary strategy of guerezas, there is considerable dietary variability among even neighboring populations experiencing different degrees of habitat fragmentation and degradation. This dietary flexibility may explain the relatively high tolerance of guerezas to human disturbance across their geographic distribution.

The subspecific taxonomy and distribution of geladas (Theropithecus gelada Rüppell, 1835) remains uncertain. Recent molecular studies based on mitochondrial sequence data revealed a geographically structured, three‐deme population, suggesting that there are three evolutionary units of geladas. However, mitochondrial distributions do not always recover population relationships, particularly in taxa with a complex history of isolation and gene flow. We therefore analysed the nuclear genetic population structure of the global gelada population based on 20 microsatellite loci in 43 samples from across its geographic range. FST values, a STRUCTURE analysis and a principal coordinate analysis (PCoA) confirmed the three‐deme population structure corresponding to the mitochondrial population structure. Therefore, our analyses provide additional support for three evolutionary units in geladas, corresponding to (a) a northern (north of Lake Tana, primarily in the Simien Mountains, previously classified as Theropithecus gelada gelada Rüppell, 1835), (b) a central (between Addis Ababa and the highlands east of Lake Tana, previously classified as Theropithecus gelada obscurus Heuglin, 1863) and (c) a southern (south of the Rift Valley, previously tentatively classified as Theropithecus gelada arsi Shotake et al., 2016, Anthropological Science, 124, 157) population. These results pave the way for future conservation decisions and highlight that the gelada population boundaries need more fine‐grained genetic sampling and phenotypic analyses, in particular for their taxonomic ranking.

Background: A beneficial composition of the microbiome is essential for maintaining human health and to protect the body against pathogens. The identification of microbes with oncogenic potential suggests a possible link between changes in the gastrointestinal microbiome composition and the onset of cancer. Childhood cancer is still the predominant cause of death among children over a year in Western countries. However, a profound understanding of the changes in the composition of the microbiome in the onset or progression of childhood cancer is still lacking. Methods: We characterized the gut microbiota in a cohort of Norwegian children diagnosed with cancer using fecal samples before the onset of treatment. Samples were collected in the Norwegian Childhood Cancer Biobank (NCCB) and compared to a control group of children attending two diverse kindergartens in Oslo, Norway. The data of 16S rRNA gene amplicon sequencing were analyzed by non-metric multidimensional scaling (NMMS) of amplicon sequence variants (ASVs) relative abundance data. Results: Our results revealed 11 prevalent 16S rRNA gene sequence variants with significantly differential occurrence between the patient and the control groups. Eight of these taxa were depleted in children diagnosed with cancer, with three of these eight classified as Faecalibacterium prausnitzii. Conclusions: Our observations indicate that the gut microbiota may play an important role in understanding the physiological changes associated with childhood cancer. However, further studies are required to validate if variations in the microbial community could be used as an early indicator of the presence of cancer in the future.

Primates are prolific dispersers of seeds via endozoochory (i.e., defecation and spitting). In contrast, epizoochorous seed dispersal (i.e., via adhesion to fur) has rarely been observed in primates. On the Guassa Plateau in north-central Ethiopia, grass-eating geladas (Theropithecus gelada) regularly carry on their fur the barbed seeds of a commonly eaten plant, a low-lying herbaceous forb called Agrocharis melanantha [Apiaceae]. Here, we describe the basic ecology of this plant–primate relationship. For 24 months (November 2017–December 2019), we monitored the number and location of A. melanantha seeds on the fur of geladas (n = 225 individuals) from four age-sex classes: adult males, adult females, juveniles, and infants. Seed accumulation (n = 12649 seeds in total) was seasonal and closely tracked patterns of landscape vegetation phenology, peaking in September near the end of the rainy season. During seasonal periods of heavy seed accumulation, larger animals carried more seeds, which accumulated most often on the hindlimbs and on the long-haired “cape” (a secondary sexual characteristic) of adult males. Geladas almost never removed seeds during self- or social grooming. Rather, data on seed gain and loss from focal follows indicate that geladas gain and lose seeds every few minutes as they walk and sit in an upright feeding position amidst terrestrial vegetation. We estimate that, on average, geladas disperse seeds roughly 80 m from their parent plants. Geladas appear to exert negative and positive fitness impacts on A. melanantha by regularly consuming its herbaceous and underground tissues and dispersing its seeds. Abstract in Amharic is available with online material.

Field studies of black-and-white colobus monkeys (Colobus spp.), African colobines endemic to the forests of equatorial and West Africa, first began in the mid-1950s. Coveted as sources of wild meat and for their often beautiful pelages, most Colobus spp. are today threatened with extinction. Yet, Colobus are also among the most intensively studied colobine monkeys. A wealth of information now exists on this genus, knowledge which has advanced our understanding of many aspects of primate natural history, especially the extraordinary variability in ecology and behaviour that can arise even within a small clade of monkeys with physical adaptations to largely folivorous diets. In this chapter, I review the literature on the habitats, diets, activity patterns, range use patterns, predation threats, social organizations, and sexual behaviour and reproduction of the five monkey species that belong to the genus Colobus (C. angolensis, C. guereza, C. polykomos, C. satanas, and C. vellerosus). I highlight similarities and differences among the different species and populations, and conclude with suggestions for the most exciting and pressing future studies that should be carried out on the natural history of the black-and-white colobus monkeys.

Neopterin, a product of activated white blood cells, is a marker of nonspecific inflammation that can capture variation in immune investment or disease-related immune activity and can be collected noninvasively in urine. Mounting studies in wildlife point to lifetime patterns in neopterin related to immune development, aging, and certain diseases, but rarely are studies able to assess whether neopterin can capture multiple concurrent dimensions of health and disease in a single system. We assessed the relationship between urinary neopterin stored on filter paper and multiple metrics of health and disease in wild geladas (Theropithecus gelada), primates endemic to the Ethiopian highlands. We tested whether neopterin captures age-related variation in inflammation arising from developing immunity in infancy and chronic inflammation in old age, inflammation related to intramuscular tapeworm infection, helminth-induced anti-inflammatory immunomodulation, and perturbations in the gastrointestinal microbiome. We found that neopterin had a U-shaped relationship with age, no association with larval tapeworm infection, a negative relationship with metrics related to gastrointestinal helminth infection, and a negative relationship with microbial diversity. Together with growing research on neopterin and specific diseases, our results demonstrate that urinary neopterin can be a powerful tool for assessing multiple dimensions of health and disease in wildlife.

Survival at high altitude requires adapting to extreme conditions such as environmental hypoxia. To understand high-altitude adaptations in a primate, we assembled the genome of the gelada (Theropithecus gelada), an endemic Ethiopian monkey, and complemented it with population resequencing, hematological, and morphometric data. Unexpectedly, we identified a novel karyotype that may contribute to reproductive isolation between gelada populations. We also identified genomic elements including protein-coding sequences and gene families that exhibit accelerated changes in geladas and may contribute to high-altitude adaptation. Our findings lend insight into mechanisms of speciation and adaptation while providing promising avenues for functional hypoxia research.

To cope with climate change and population growth, the continent urgently needs more home-grown researchers, argue Anagaw Atickem, Nils Chr. Stenseth and colleagues. To cope with climate change and population growth, the continent urgently needs more home-grown researchers, argue Anagaw Atickem, Nils Chr. Stenseth and colleagues.

Home range and activity patterns of animals are important elements for wildlife management and conservation practices. We examined seasonal home range and daily activity patterns of the endangered Swayne’s hartebeest (Alcelaphus buselaphus swaynei) in Maze National Park, Ethiopia. We tracked two groups of Swayne’s hartebeests in open grassland for 1 year. Each group’s daily activities (0700–1900 h) and GPS locations were recorded at 15-min intervals on 5 days every month. Activities were grouped into five behavioral categories: feeding, resting, traveling, vigilance, and other. In addition, we carried out nocturnal monitoring during full moon periods to further document movements patterns. We produced 95% and 50% kernel density estimates (KDE) of home range sizes for each group. Home range estimates did not vary across seasons. Feeding and traveling peaked during the early morning and late afternoon, whereas resting occurred most frequently during the midday hours in both seasons. The proportion of time spent feeding was higher during the dry season, whereas a greater proportion of time was spent resting during the wet season. Vigilance behavior occurred consistently throughout the day during both seasons. Time spent feeding and traveling did not vary significantly between seasons. Activity patterns of Swayne’s hartebeests are strongly influenced both by time of day and season, while home range size is less influenced by seasonality and may instead reflect temporal variation in food availability. Our findings will help to inform management strategies and conserve one of the last two extant populations of Swayne’s hartebeests.

Understanding the basic natural history of threatened primate taxa is crucial to developing and implementing successful conservation strategies for them. Data on feeding ecology and activity patterns are particularly important for identifying the strategies through which primates invest time and foraging effort towards survival and reproduction at a given locale. Here, we report the results of the first study of the diet and activity budget of Arsi geladas, a population of < 1000 individuals endemic to a heavily disturbed region of the southern Ethiopian Highlands and believed to represent a new taxon of geladas. We conducted our research on a band of 34 individuals belonging to five, one-male units at Indetu, eastern Arsi, Ethiopia, from August 2010 to May 2011 (excluding March 2011). Feeding accounted for 41.7% of total scans, followed by moving (20.3%), resting (19.0%), and social behavior (19.0%). Feeding and moving increased and resting and socializing decreased during the dry season when food availability was probably lower than during the wet season. Geladas ate mostly graminoid leaves (51.7% of feeding scans) though they also consumed graminoid rhizomes (24.4%), forb tubers (7.1%), forb leaves (7.1%), cactus, shrub, and tree fruits (3.6%), graminoid corms (1.7%), forb roots (1.6%), and unidentified items (3.0%). Underground foods (corms, rhizomes, roots, and tubers) accounted for 22–47% (mean = 35%) of the monthly (n = 9) diet and were eaten slightly more during the wet season than during the dry season. Contributions of human crops to the gelada diet could not be quantified without creating conflict between farmers and researchers, though we did note that geladas visited farms on 5–10% of study days. Threats from farmers, children, and dogs limited the geladas’ access to crops once they entered the farms. Further research involving questionnaire surveys of farmers, direct observation of crop damage by geladas, and DNA metabarcoding of gelada feces are crucial to the development of strategies to mitigate human-gelada conflict in the densely populated Arsi Zone of Ethiopia.

African wolves (AWs) are sympatric with endangered Ethiopian wolves (EWs) in parts of their range. Scat analyses have suggested a dietary overlap between AWs and EWs, raising the potential for exploitative competition, and a possible conservation threat to EWs. However, in contrast to that of the well-studied EW, the foraging ecology of AWs remains poorly characterized. Accordingly, we studied the foraging ecology of radio-collared AWs ( n = 11 individuals) at two localities with varying levels of anthropogenic disturbance in the Ethiopian Highlands, the Guassa-Menz Community Conservation Area (GMCCA) and Borena-Saynt National Park (BSNP), accumulating 845 h of focal observation across 2952 feeding events. We also monitored rodent abundance and rodent trapping activity by local farmers who experience conflict with AWs. The AW diet consisted largely of rodents (22.0%), insects (24.8%), and goats and sheep (24.3%). Of the total rodents captured by farmers using local traps during peak barley production (July to November) in GMCCA, averaging 24.7 ± 8.5 rodents/hectare/day, 81% ( N = 3009) were scavenged by AWs. Further, of all the rodents consumed by AWs, most (74%) were carcasses. These results reveal complex interactions between AWs and local farmers, and highlight the scavenging niche occupied by AWs in anthropogenically altered landscapes in contrast to the active hunting exhibited by EWs in more intact habitats. While AWs cause economic damage to local farmers through livestock predation, they appear to play an important role in scavenging pest rodents among farmlands, a pattern of behaviour which likely mitigates direct and indirect competition with EWs. We suggest two routes to promote the coexistence of AWs and EWs in the Ethiopian highlands: local education efforts highlighting the complex role AWs play in highland ecosystems to reduce their persecution, and enforced protection of intact habitats to preserve habitat preferred by EWs.

Reliable data on the distribution and threats facing primate species are crucial to identifying priority sites for conservation and designing effective management plans. Boutourlini’s blue monkey (Cercopithecus mitis boutourlinii) is a little-known arboreal primate endemic to the forests of western Ethiopia. This subspecies is categorized as Vulnerable on the International Union for Conservation of Nature (IUCN) Red List and the distribution of extant populations is largely unknown. To increase our knowledge of the spatial distribution and conservation status of Boutourlini’s blue monkey, we carried out intensive reconnaissance surveys from January 2010 to May 2011 across approximately 40% of its potential range and conducted interviews with local people at each of the survey locations. We carried out geospatial analyses and mapped the distribution of Boutourlini’s blue monkey localities with respect to elevation, protected area status, and changes in forest cover over time using ArcGIS 10.4.0. Through our surveys, we discovered 30 previously unknown Boutourlini’s blue monkey populations in three administrative regions of western Ethiopia (Amhara, Oromia, and Southern Nations, Nationalities and People’s Regions). A total of 34 different groups were sighted and counted at the survey sites, averaging 14.7 members (range 8–23) per group. There are now 32 Boutourlini’s blue monkey populations of recently confirmed occurrence at altitudes ranging from 1039 to 2780 m asl, seven in forests of greater than 50 km2. Crop feeding by Boutourlini’s blue monkeys was reported by people at seven sites and confirmed through direct observation at three of these sites. None of the known extant populations of Boutourlini’s blue monkeys occur within a strictly protected area (e.g., national park) where exploitative human activities are outlawed. A complete reassessment of the distribution and conservation status of Boutourlini’s blue monkey will require further surveys across the remaining approximately 60% of its potential range.

Primates inhabiting human‐modified landscapes often exploit matrix habitat to supplement their diet with cultivated foods, at times resulting in economic losses and conflict with local people. Understanding human‐nonhuman primate interactions and the attitudes and perceptions of local people towards crop feeding species are crucial to designing effective species‐based management plans. Over a 12‐month period, we used scan sampling to study the consumption of cultivated foods and matrix use patterns by two habituated groups of Bale monkeys (Chlorocebus djamdjamensis ), Ethiopian‐endemic bamboo specialists, in two forest fragments (Kokosa and Afursa) set amidst human settlements and farmland in the southern Ethiopian Highlands. Further, we conducted interviews with local people to document their attitudes and perceptions towards Bale monkeys at the two sites. We found that Bale monkeys at Kokosa, a more degraded habitat by most measures, consumed significantly more cultivated foods than their counterparts at Afursa. Moreover, Bale monkeys at Kokosa spent significantly more time in the matrix than in the forest habitat, while monkeys at Afursa spent significantly less time in the matrix than in the forest habitat. Not surprisingly, local people displayed a more negative attitude towards monkeys inhabiting Kokosa than those inhabiting Afursa. The differences in Bale monkey cultivated food consumption and matrix use patterns—as well as in local people's attitudes and perceptions towards Bale monkeys—between Kokosa and Afursa are probably associated with differences in habitat structure, degree of habitat alteration, and land‐use practices between the sites. We conclude that to ensure long‐term coexistence between Bale monkeys and local people in human‐modified landscapes, it is vital to incorporate nearby matrix habitats into management plans and to work closely with local communities to develop effective nonlethal crop protection strategies, thereby reducing the likelihood of negative interactions between Bale monkeys and humans.

Predation is widely believed to exert strong selective pressure on primate behavior and ecology but is difficult to study and rarely observed. In this study, we describe seven encounters between lone wild leopards (Panthera pardus) and herds of geladas (Theropithecus gelada) over a 6-year period in an intact Afroalpine grassland ecosystem at the Guassa Community Conservation Area, Ethiopia. Three encounters consisted of attempted predation on geladas by leopards, one of which was successful. All three attacks occurred in low-visibility microhabitats (dominated by tussock graminoids, mima mounds, or tall shrubs) that provided leopards with hidden viewsheds from which to ambush geladas. An additional four encounters did not result in an attempted attack but still document the consistently fearful responses of geladas to leopards. In encounters with leopards, geladas typically gave alarm calls (n = 7 of 7 encounters), reduced interindividual distances (n = 5), and collectively fled towards or remained at their sleeping cliffs (n = 7), the only significant refugia in the open-country habitat at Guassa. Geladas did not engage in mobbing behavior towards leopards. Encounters with leopards tended to occur on days when gelada herd sizes were small, raising the possibility that leopards, as ambush hunters, might stalk geladas on days when fewer eyes and ears make them less likely to be detected. We compare the behavioral responses of geladas to leopards at Guassa with those previously reported at Arsi and the Simien Mountains and discuss how gelada vulnerability and responses to leopards compare with those of other primate species living in habitats containing more refugia. Lastly, we briefly consider how living in multilevel societies may represent an adaptive response by geladas and other open-country primates to predation pressure from leopards and other large carnivores.

Research is a highly competitive profession where evaluation plays a central role; journals are ranked and individuals are evaluated based on their publication number, the number of times they are cited and their h-index. Yet such evaluations are often done in inappropriate ways that are damaging to individual careers, particularly for young scholars, and to the profession. Furthermore, as with all indices, people can play games to better their scores. This has resulted in the incentive structure of science increasingly mimicking economic principles, but rather than a monetary gain, the incentive is a higher score. To ensure a diversity of cultural perspectives and individual experiences, we gathered a team of academics in the fields of ecology and evolution from around the world and at different career stages. We first examine how authorship, h-index of individuals and journal impact factors are being used and abused. Second, we speculate on the consequences of the continued use of these metrics with the hope of sparking discussions that will help our fields move in a positive direction. We would like to see changes in the incentive systems, rewarding quality research and guaranteeing transparency. Senior faculty should establish the ethical standards, mentoring practices and institutional evaluation criteria to create the needed changes.

With 60% of all primate species now threatened with extinction and many species only persisting in small populations in forest fragments, conservation action is urgently needed. But what type of action? Here we argue that restoration of primate habitat will be an essential component of strategies aimed at conserving primates and preventing the extinctions that may occur before the end of the century and propose that primates can act as flagship species for restoration efforts. To do this we gathered a team of academics from around the world with experience in restoration so that we could provide examples of why primate restoration ecology is needed, outline how primates can act as flagship species for restoration efforts of tropical forest, review what little is known about how primate populations respond to restoration efforts, and make specific recommendations of the next steps needed to make restoration of primate populations successful. We set four priorities: (1) academics must effectively communicate both the value of primates and the need for restoration; (2) more research is needed on how primates contribute to forest restoration; (3) more effort must be put into Masters and PhD level training for tropical country nationals; and finally (4) more emphasis is needed to monitor the responses of regenerating forest and primate populations where restoration efforts are initiated. We are optimistic that populations of many threatened species can recover, and extinctions can be prevented, but only if concerted large-scale efforts are made soon and if these efforts include primate habitat restoration.

Ethiopian shade coffee plantations are well documented to be bird-friendly and act as refuges for disappearing tree species. The extent to which these plantations support mammal conservation, as well as mammal sensitivity to coffee intensification, remain little studied. We studied the distribution and diversity of mammals under three coffee management systems of differing intensities (i.e., semi-forest, semi-plantation, and plantation) and in nearby natural forests in Belete-Gera Forest Priority Area, southwestern Ethiopia. We detected mammals using 30 infrared camera traps at 90 stations for a total of 4142 camera days. We used the Shannon-Wiener diversity index for diversity analysis, generalized linear mixed model for comparison of independent detection, and non-metric multidimensional scaling to show the mammalian community composition. We recorded 8815 digital videos and a total of 23 mammal species. The overall species richness, diversity, and detection of mammals did not differ between the two traditional shade coffee management systems and the natural forest but was lower in the plantation coffee system. The mammal community composition also shows variation in resilience to coffee management intensity, with primates appearing to be generally more tolerant to management intensification. We ultimately show that traditionally managed Ethiopian shade coffee farms shelter diverse mammal communities, comparable to those in nearby natural forests. Therefore, supporting traditional coffee management practices and certifying them as mammal-friendly should be implemented as strategies for the conservation of mammals, as natural forests continue to decline in Ethiopia.

International audience; AbstractThe rise and spread of tropical grasslands was a signal event in the Cenozoic, causing many ungulates to evolve adaptations to a diet of graminoid tissues, or graminivory. In parallel, a lineage of monkeys (Theropithecus) is distinguished among primates for its large size and commitment to graminivory, a trait expressed by species throughout the Plio-Pleistocene fossil record and T. gelada, the sole surviving species today. An open question concerns the mechanics of how fossil species of Theropithecus handled graminoid tissues. They might have exhibited preference, selecting tissues within a given tuft, or they might have practiced indiscriminate bulk-feeding in a manner similar to large grazing ungulates. To differentiate between these handling behaviors, we used time- and graminivore-calibrated carbon stable isotope values to show progressive reliance on high-throughput bulk-feeding graminivory. Variation in this behavior explains a significant amount of variation in body mass through time, and we describe these covarying traits, which peaked during the Pleistocene, as evolutionary traps. To support this characterization, we report evidence of temporal increases in strontium isotope variability among North African theropiths, a result that suggests greater lifetime travel and energetic costs in response to diminishing food resources, a probable factor in the extinction of T. oswaldi, the largest monkey that ever lived.

Bryobia abyssiniae Fashing & Ueckermann, a recently discovered species, is described using DNA-barcoding as well as morphological features of the adult female and all post-embryonic instars. The species is characterized by remarkable propodosomal lobe variation. A lack of variation in molecular markers indicates that the several forms observed reflect intraspecific variability in this apparently all-female species. Its host plant, a giant lobelia (Lobelia rhynchopetalum Hemsl.; Campanulaceae), is endemic to the Ethiopian highlands. A discussion of climate at the collection locality, the host plant, and notes on biology are also included. Additionally, we suggest that a minimum of 5% sequence difference in the mitochondrial cytochrome c oxidase subunit I region will be needed to differentiate Bryobia species.

Carnivore populations are declining globally due to range contraction, persecution and prey depletion. One consequence of these patterns is increased range and niche overlap with other carnivores, and thus an elevated potential for competitive exclusion. Here, we document competition between an endangered canid, the Ethiopian wolf (EW), and the newly discovered African wolf (AW) in central Ethiopia. The diet of the ecological specialist EW was dominated by rodents, whereas the AW consumed a more diverse diet also including insects and non-rodent mammals. EWs used predominantly intact habitat, whereas AWs used mostly areas disturbed by humans and their livestock. We observed 82 encounters between the two species, of which 94% were agonistic. The outcomes of agonistic encounters followed a territory-specific dominance pattern, with EWs dominating in intact habitat and AWs in human-disturbed areas. For AWs, the likelihood of winning encounters also increased with group size. Rodent species consumed by EWs were also available in the human-disturbed areas, suggesting that these areas could be suitable habitat for EWs if AWs were not present. Increasing human encroachment not only affects the prey base of EWs, but also may impact their survival by intensifying competition with sympatric AWs.

Background Understanding the effects of habitat modification on the feeding strategies of threatened species is essential to designing effective conservation management plans. Bale monkeys (Chlorocebus djamdjamensis) are endemic to the rapidly shrinking montane forests of the southern Ethiopian Highlands. Most populations inhabit continuous bamboo forest subsisting largely on the young leaves and shoots of a single species of bamboo. Because of habitat disturbance in recent decades, however, there are now also several dozen small populations inhabiting isolated forest fragments where bamboo has been degraded. During 12-months, we assessed Bale monkey responses to habitat degradation by comparing habitat composition, phenological patterns, and feeding ecology in a largely undisturbed continuous forest (Continuous groups A and B) and in two fragments (Patchy and Hilltop groups). Results We found that habitat quality and food availability were much lower in fragments than in continuous forest. In response to the relative scarcity of bamboo in fragments, Bale monkeys spent significantly less time feeding on the young leaves and shoots of bamboo and significantly more time feeding on non-bamboo young leaves, fruits, seeds, stems, petioles, and insects in fragments than in continuous forest. Groups in fragments also broadened their diets to incorporate many more plant species (Patchy: ≥ 47 and Hilltop: ≥ 35 species)—including several forbs, graminoids and cultivated crops—than groups in continuous forest (Continuous A: 12 and Continuous B: 8 species). Nevertheless, bamboo was still the top food species for Patchy group (30% of diet) as well as for both continuous forest groups (mean = 81%). However, in Hilltop group, for which bamboo was especially scarce, Bothriochloa radicans (Poaceae), a grass, was the top dietary species (15% of diet) and bamboo ranked 10th (2%). Conclusions We demonstrate that Bale monkeys are more dietarily flexible than previously thought and able to cope with some degradation of their primary bamboo forest habitat. However, crop raiding and other terrestrial foraging habits more common among fragment groups may place them at greater risk of hunting by humans. Thus, longitudinal monitoring is necessary to evaluate the long-term viability of Bale monkey populations in fragmented habitats. Electronic supplementary material The online version of this article (10.1186/s12898-018-0161-4) contains supplementary material, which is available to authorized users.

Studies of the effects of habitat fragmentation and degradation on primate positional behavior, strata use, and substrate utilization offer valuable insights into the behavioral and ecological flexibility of primates whose habitats have undergone extensive anthropogenic disturbance. In this study, we evaluated how positional behavior, strata use, and substrate utilization differed between Bale monkeys (Chlorocebus djamdjamensis)-bamboo-eating cercopithecids endemic to the southern Ethiopian Highlands-occupying continuous versus fragmented forests. Bale monkeys in forest fragments (where bamboo had been degraded or eradicated) spent significantly more time on the ground and in understory strata whereas those in continuous forest spent significantly more time in the middle and upper strata. Bale monkeys in forest fragments also spent significantly more time walking and galloping and significantly less time climbing than those in continuous forest. Our results suggest that, unlike the primarily arboreal Bale monkeys in continuous forest, Bale monkeys in forest fragments should be characterized as semi-terrestrial. In response to habitat disturbance in fragments, we observed a greater emphasis on terrestrial foraging and travel among Bale monkeys in these human altered habitats, which may put them at greater risk of predation and conflict with nearby human populations. Bale monkeys in fragments exhibit flexibility in their positional behavioral repertoire and their degree of terrestriality is more similar to their sister taxa in Chlorocebus than to Bale monkeys in continuous forest. These findings suggest that habitat alteration may compel Bale monkeys to exhibit semi-terrestrial behaviors crucial for their persistence in human-modified habitats. Our results contribute to a growing body of literature on primate behavioral responses to anthropogenic modification of their habitats and provide information that can contribute to the design of appropriate conservation management plans.

Background The gelada monkey (Theropithecus gelada), endemic to the Ethiopian highlands, is the only graminivorous primate, i.e., it feeds mainly on grasses and sedges. In spite of known dental, manual, and locomotor adaptations, the intestinal anatomy of geladas is similar to that of other primates. We currently lack a clear understanding of the adaptations in digestive physiology necessary for this species to subsist on a graminoid-based diet, but digestion in other graminivores, such as ruminants, relies heavily on the microbial community residing in the gastrointestinal (GI) system. Furthermore, geladas form complex, multilevel societies, making them a suitable system for investigating links between sociality and the GI microbiota. Results Here, we explore the gastrointestinal microbiota of gelada monkeys inhabiting an intact ecosystem and document how factors like multilevel social structure and seasonal changes in diet shape the GI microbiota. We compare the gelada GI microbiota to those of other primate species, reporting a gradient from geladas to herbivorous specialist monkeys to dietary generalist monkeys and lastly humans, the ultimate ecological generalists. We also compare the microbiotas of the gelada GI tract and the sheep rumen, finding that geladas are highly enriched for cellulolytic bacteria associated with ruminant digestion, relative to other primates. Conclusions This study represents the first analysis of the gelada GI microbiota, providing insights into the adaptations underlying graminivory in a primate. Our results also highlight the role of social organization in structuring the GI microbiota within a society of wild animals. Electronic supplementary material The online version of this article (10.1186/s40168-018-0468-6) contains supplementary material, which is available to authorized users.

Background Species with a restricted geographic distribution, and highly specialized habitat and dietary requirements, are particularly vulnerable to extinction. The Bale monkey (Chlorocebus djamdjamensis) is a little-known arboreal, bamboo-specialist primate endemic to the southern Ethiopian Highlands. While most Bale monkeys inhabit montane forests dominated by bamboo, some occupy forest fragments where bamboo is much less abundant. We used mitochondrial DNA (mtDNA) sequences to analyse the genetic structure and evolutionary history of Bale monkeys covering the majority of their remaining distribution range. We analysed 119 faecal samples from their two main habitats, continuous forest (CF) and fragmented forests (FF), and sequenced 735 bp of the hypervariable region I (HVI) of the control region. We added 12 orthologous sequences from congeneric vervets (C. pygerythrus) and grivets (C. aethiops) as well as animals identified as hybrids, previously collected in southern Ethiopia. Results We found strong genetic differentiation (with no shared mtDNA haplotypes) between Bale monkey populations from CF and FF. Phylogenetic analyses revealed two distinct and highly diverged clades: a Bale monkey clade containing only Bale monkeys from CF and a green monkey clade where Bale monkeys from FF cluster with grivets and vervets. Analyses of demographic history revealed that Bale monkey populations (CF and FF) have had stable population sizes over an extended period, but have all recently experienced population declines. Conclusions The pronounced genetic structure and deep mtDNA divergence between Bale monkey populations inhabiting CF and FF are likely to be the results of hybridization and introgression of the FF population with parapatric Chlorocebus species, in contrast to the CF population, which was most likely not impacted by hybridization. Hybridization in the FF population was probably enhanced by an alteration of the bamboo forest habitat towards a more open woodland habitat, which enabled the parapatric Chlorocebus species to invade the Bale monkey's range and introgress the FF population. We therefore propose that the CF and FF Bale monkey populations should be managed as separate units when developing conservation strategies for this threatened species. Electronic supplementary material The online version of this article (10.1186/s12862-018-1217-y) contains supplementary material, which is available to authorized users.

Objectives The birth process has been studied extensively in many human societies, yet little is known about this essential life history event in other primates. Here, we provide the most detailed account of behaviors surrounding birth for any wild nonhuman primate to date. Materials and Methods Over a recent ∼10-year period, we directly observed 15 diurnal births (13 live births and 2 stillbirths) among geladas (Theropithecus gelada) at Guassa, Ethiopia. During each birth, we recorded the occurrence (or absence) of 16 periparturitional events, chosen for their potential to provide comparative evolutionary insights into the factors that shaped birth behaviors in humans and other primates. Results We found that several events (e.g., adopting standing crouched positions, delivering infants headfirst) occurred during all births, while other events (e.g., aiding the infant from the birth canal, licking infants following delivery, placentophagy) occurred during, or immediately after, most births. Moreover, multiparas (n = 9) were more likely than primiparas (n = 6) to (a) give birth later in the day, (b) isolate themselves from nearby conspecifics while giving birth, (c) aid the infant from the birth canal, and (d) consume the placenta. Discussion Our results suggest that prior maternal experience may contribute to greater competence or efficiency during the birth process. Moreover, face presentations (in which infants are born with their neck extended and their face appearing first, facing the mother) appear to be the norm for geladas. Lastly, malpresentations (in which infants are born in the occiput anterior position more typical of human infants) may be associated with increased mortality in this species. We compare the birth process in geladas to those in other primates (including humans) and discuss several key implications of our study for advancing understanding of obstetrics and the mechanism of labor in humans and nonhuman primates.

Chewing efficiency has been associated with fitness in mammals, yet little is known about the behavioral, ecological, and morphological factors that influence chewing efficiency in wild animals. Although research has established that dental wear and food material properties independently affect chewing efficiency, few studies have addressed the interaction among these factors. We examined chewing efficiency, measured as mean fecal particle size, as a function of seasonal shifts in diet (and corresponding changes in food fracture toughness) in a single breeding population of a grazing primate, the gelada monkey, at Guassa, Ethiopia. We also measured dental topographic traits (slope, angularity, and relief index) and relative two- and three-dimensional shearing crest lengths in a cross-sectional wear series of gelada molars. Chewing efficiency decreased during the dry season, a pattern corresponding to the consumption of foods with higher fracture toughness. Older individuals experienced the most pronounced decreases in chewing efficiency between seasons, implicating dental wear as a causal factor. This pattern is consistent with our finding that dental topographic metrics and three-dimensional relative shearing crest lengths were lowest at the last stage of wear. Integrating these lines of behavioral, ecological, and morphological evidence provides some of the first empirical support for the hypothesis that food fracture toughness and dental wear together contribute to chewing efficiency. Geladas have the highest chewing efficiencies measured thus far in primates, and may be analogous to equids in their emphasis on dental design as a means of particle size reduction in the absence of highly specialized digestive physiology.

Recent evidence suggests that several extinct primates, including contemporaneous Paranthropus boisei and Theropithecus oswaldi in East Africa, fed largely on grasses and sedges (i.e., graminoids). As the only living primate graminivores, gelada monkeys (Theropithecus gelada) can yield insights into the dietary strategies pursued by extinct grass- and sedge-eating primates. Past studies of gelada diet were of short duration and occurred in heavily disturbed ecosystems. We conducted a long-term study of gelada feeding ecology in an intact Afroalpine ecosystem at Guassa, Ethiopia. Geladas at Guassa consumed ≥56 plant species, ≥20 invertebrate species, one reptile species, and the eggs of one bird species over a 7-year period. The annual diet consisted of 56.8% graminoid parts, 37.8% forb parts, 2.8% invertebrates, and 2.6% other items, although geladas exhibited wide variability in diet across months at Guassa. Edible forbs were relatively scarce at Guassa but were strongly selected for by geladas. Tall graminoid leaf and tall graminoid seed head consumption correlated positively, and underground food item consumption correlated negatively, with rainfall over time. Geladas at Guassa consumed a species-rich diet dominated by graminoids, but unlike geladas in more disturbed habitats also ate a diversity of forbs and invertebrates along with occasional vertebrate prey. Although graminoids are staple foods for geladas, underground food items are important “fallback foods.” We discuss the implications of our study, the first intensive study of the feeding ecology of the only extant primate graminivore, for understanding the dietary evolution of the theropith and hominin putative graminivores, Theropithecus oswaldi and Paranthropus boisei. Am J Phys Anthropol 155:1–16, 2014. © 2014 Wiley Periodicals, Inc.

Comparisons of the behavior and ecology of primates living in intact and fragmented forest are critical to the development of conservation strategies for the many primate taxa threatened by habitat loss. From July 2009 to April 2010, we investigated the habitat use, ranging behavior, and diet of two groups of Boutourlini’s blue monkeys (Cercopithecus mitis boutourlinii), a subspecies endemic to western Ethiopia, whose habitats had experienced different levels of disturbance at Jibat Forest. Forest Group occupied primarily continuous tree-dominated forest with little human disturbance whereas Fragment Group inhabited a heavily degraded 2- to 3-km2 forest fragment nearly surrounded by farmland and connected tenuously to the continuous forest by a narrow corridor of riverine forest. Mean daily path lengths for both groups were nearly identical (Forest Group: 799 m; Fragment Group: 783 m) and exhibited little seasonal variability. The mean home range areas of Forest Group and Fragment Group were 72.0 and 61.2 ha, respectively. Forest Group (N = 2232 feeding records) fed mostly on fruits (52.5 %), though they also ate animal prey (14.7 %), young leaves (11.1 %), shoots (8.7 %), and flowers (7.3 %). In contrast, fruits accounted for only 17.0 % of Fragment Group’s diet (N = 2903 feeding records), with shoots (29.8 %), young leaves (17.1 %), animal prey (13.1 %), seeds (9.6 %), and flowers (6.8 %) also making substantial contributions to their diet. Only Fragment Group engaged in crop raiding, consuming seeds from barley and wheat extensively (33–41 % of diet) during 2 mo. Fragment Group (N = 33) ate more plant species than Forest Group (N = 24), though both groups exploited a small number of plant species relative to other subspecies of blue monkeys. Our study revealed that, like most other blue monkey subspecies, Boutourlini’s blue monkeys are quite flexible in the habitats they occupy as well as in their foraging habits. Despite this ecological flexibility, the long-term conservation of Boutourlini’s blue monkey is far from assured given its limited distribution, the rapidly growing human population, and the high rates of forest clearance in western Ethiopia.

Understanding the extent to which primates in forest fragments can adjust behaviorally and ecologically to changes caused by deforestation is essential to designing conservation management plans. During a 12-month period, we studied the effects of habitat loss and degradation on the Ethiopian endemic, bamboo specialist, Bale monkey (Chlorocebus djamdjamensis) by comparing its habitat quality, activity budget, ranging ecology and habitat use in continuous forest and two fragments. We found that habitat loss and fragmentation resulted in major differences in vegetation composition and structure between forest types. We also found that Bale monkeys in continuous forest spent more time feeding and traveling and less time resting and socializing than monkeys in fragments. Bale monkeys in continuous forest also had higher movement rates (m/hr) than monkeys in fragments. Bale monkeys in continuous forest used exclusively bamboo and mixed bamboo forest habitats while conspecifics in fragments used a greater variety of habitats including human use areas (i.e., matrix). Our findings suggest that Bale monkeys in fragments use an energy minimization strategy to cope with the lower availability of the species' primary food species, bamboo (Arundinaria alpina). We contend that Bale monkeys may retain some of the ancestral ecological flexibility assumed to be characteristic of the genus Chlorocebus, within which all extant species except Bale monkeys are regarded as ecological generalists. Our results suggest that, like other bamboo eating primates (e.g., the bamboo lemurs of Madagascar), Bale monkeys can cope with a certain threshold of habitat destruction. However, the long-term conservation prospects for Bale monkeys in fragments remain unclear and will require further monitoring to be properly evaluated.

Until recently, the Bale monkey (Chlorocebus djamdjamensis), an arboreal primate endemic to the southern Ethiopian highlands, remained virtually unstudied, and its distribution pattern inadequately documented. To broaden our knowledge of the species’ distribution and abundance, we carried out interviews with local people and total count surveys for Bale monkeys across 67 fragmented forest sites in human-dominated landscapes in the Oromia and Southern Nations, Nationalities, and People's Regions, Ethiopia. From January 2010 to May 2011, we discovered 26 new Bale monkey populations inhabiting forest fragments at elevations ranging from 2,355 to 3,204 m asl. Across these populations, we recorded 37 groups ranging in size from 9 to 29 individuals (Mean = 19.5, SD = 4.5), for a total of 722 individuals. Black-and-white colobus monkeys (Colobus guereza) were sympatric with Bale monkeys at all sites, while grivet monkeys (Chlorocebus aethiops) were found only at sites where Bale monkeys did not occur. All of the newly discovered Bale monkey sites once contained bamboo forest, though at 35% of the sites bamboo forest had been eliminated during the past two decades. The persistence of Bale monkeys at fragmented sites lacking bamboo suggests greater habitat flexibility for the species than previously thought, though the long-term viability of populations both with and without bamboo remains uncertain. Human hunting in response to crop raiding, a behavior the monkeys engaged in at all sites, represents a major threat facing the newly discovered Bale monkey populations. Furthermore, despite their current lack of sympatry, apparently hybrid individuals between Bale monkeys and grivets were noted at three sites, posing yet another potential obstacle to Bale monkey conservation. Community conservation programs aimed at (1) protecting remaining habitat fragments, (2) planting bamboo and trees within and between fragments, and (3) reducing crop raiding represent the only hope for survival of the newly discovered Bale monkey populations. Am. J. Primatol. 74:423-432, 2012. © 2012 Wiley Periodicals, Inc.

As natural forest cover declines, planted forests have come to occupy an increasing percentage of the earth's surface, yet we know little about their suitability as alternative habitat for wildlife. Although some primate species use planted forests, few studies have compared primate populations in natural and nearby planted forests. From March 2006 to July 2010, we conducted line transect surveys and assessed group sizes and compositions in natural and nearby 60–70 year old mixed indigenous planted forest to determine the densities of diurnal primate species (Colobus guereza, Cercopithecus mitis, C. ascanius) in these two forest types at Isecheno, Kakamega Forest, Kenya. Line transect data were analyzed using the Encounter Rate, Whitesides, and Distance sampling methods, which all provided broadly consistent results. We found that all three diurnal primate species occupy both natural and planted forest at Isecheno. However, group densities of the two Cercopithecus species were 42–46% lower in planted than in natural forest. Colobus guereza achieved comparable group densities in the two forest types, although the species is found in smaller groups, and thus at lower (35%) individual density, in planted than in natural forest. Following a logging episode in the planted forest mid-way through our study, Cercopithecus ascanius group densities fell by 60% while C. mitis and Colobus guereza group densities remained stable over the next two years. Overall, our results suggest that while primate species vary in their response to habitat disturbance, planted forest has the potential to contribute to the conservation of some African monkey species. Even for the relatively flexible taxa in our study, however, 60–70 year old mixed indigenous planted forest failed to support densities comparable to those in nearby natural forest. From the perspective of Kakamega's primates, planted forests may supplement natural forest, but are not an adequate replacement for it. Am. J. Primatol. 73:1–14, 2011. © 2011 Wiley Periodicals, Inc.

Despite intensive study in humans, responses to dying and death have been a neglected area of research in other social mammals, including nonhuman primates. Two recent reports [Anderson JR, Gillies A, Lock LC. 2010. Pan thanatology. Current Biology 20:R349-R351; Biro D, Humle T, Koops K, Souse C, Hayashi M, Matsuzawa T. 2010. Chimpanzee mothers at Bossou, Guinea carry the mummified remains of their dead infants. Current Biology 20:R351-R352] offered exciting new insights into behavior toward dying and dead conspecifics in our closest living relatives-chimpanzees. Here, we provide a comparative perspective on primate thanatology using observations from a more distant human relative-gelada monkeys (Theropithecus gelada)-and discuss how gelada reactions to dead and dying groupmates differ from those recently reported for chimpanzees. Over a 3.75-year study period, we observed 14 female geladas at Guassa, Ethiopia carrying dead infants from 1hr to ≥48 days after death. Dead infants were carried by their mothers, other females in their group, and even by females belonging to other groups. Like other primate populations in which extended (>10 days) infant carrying after death has been reported, geladas at Guassa experience an extreme climate for primates, creating conditions which may favor slower rates of decomposition of dead individuals. We also witnessed the events leading up to the deaths of two individuals and the responses by groupmates to these dying individuals. Our results suggest that while chimpanzee mothers are not unique among primates in carrying their dead infants for long periods, seemingly "compassionate" caretaking behavior toward dying groupmates may be unique to chimpanzees among nonhuman primates (though it remains unknown whether such "compassionate" behavior occurs outside captivity).

The large-bodied, terrestrial primates in the tribe Papionini are among the most intensely studied animals in the world, yet for some members of this tribe we know comparatively little about their evolutionary history and phylogeography. Geladas (Theropithecus gelada Rüppell, 1835), endemic primates of the Ethiopian highlands, are largely unstudied both in genetic diversity and intrageneric phylogeny. Currently, a northern and central subspecies and one isolated southern population are recognized, of which the central is classified as Least Concern, the northern as Vulnerable, and the southern is not yet assessed. The distribution and taxonomy of the subspecies remain poorly defined. Here, we estimate the mitochondrial DNA (mtDNA) diversity and phylogenetic relationships among gelada mtDNA lineages based on samples across the entire species range. We analysed 1.7 kb-long sequences of the mtDNA genome, spanning the cytochrome b gene and the hypervariable region I of the D-loop, derived from 162 faecal samples. We detected five major haplogroups or clades (south, central-1, central-2, north-1, north-2) which diverged between 0.67 and 0.43 million years ago, thus suggesting a rapid radiation, resulting in largely unresolved intrageneric phylogenetic relationships. Both, the northern and central demes contain two similarly valid haplogroups, each with little or no geographic segregation among respective haplogroups. Effective population sizes of the northern and central demes decreased during and after the last glacial maximum but remained stable for the southern deme, although on a very low level. The distribution of haplogroups within the geographic ranges of the putative gelada subspecies indicates that mtDNA sequence information does not allow reliable taxonomic inferences and thus is not sufficient for solving the taxonomic rank of the three demic populations, with the possible exception of the southern population. Nevertheless, due to the genetic differences all three populations deserve conservation efforts, in particular the smallest southern population.

Bale monkeys (Chlorocebus djamdjamensis) are little-known primates endemic to the forests of the Bale Massif and Hagere Selam regions of Ethiopia. From August 2007 to May 2008, we conducted the first ever study of the species’ behavior and ecology, focusing in particular on its diet, activity patterns, and ranging ecology in the Odobullu Forest. We studied 2 neighboring groups (group A: 55–60 members; group B: 46–50 members) and conducted behavioral scan samples on the first 2–5 individuals sighted at 15-min intervals. Feeding accounted for 65.7% of the activity budget, followed by moving (14.4%), resting (10.7%), social (7.1%), and other behaviors (2.4%). Overall diet during the study was dominated by young leaves (80.2%), though subjects also ate fruits (9.6%), flowers (3.1%), animal prey (2.3%), shoots (1.5%), stems (1.4%), mature leaves (1.1%), and roots (0.9%). Bale monkeys consumed only 11 plant species; of these, the top 5 species accounted for 94.3% of their diet. The top food item, bamboo (Arundinaria alpina), was responsible for a remarkable 76.7% of their diet, with most (95.2%) of the bamboo consumption consisting of young leaves. Mean daily path length for the study groups was 928 m and mean (100% minimum convex polygon) home range size was 15.2 ha. Though we are cautious in drawing conclusions from only 2 groups, the larger group traveled further per day and occupied a larger home range, patterns suggesting scramble competition may be occurring in Bale monkey groups at Odobullu. The dietary specialization of Bale monkeys on bamboo makes them unique among Chlorocebus spp. and suggests an intriguing ecological convergence with the golden monkeys (Cercopithecus mitis kandti) of Uganda and bamboo lemurs (Hapalemur spp.) of Madagascar. Their narrow ecological niche, limited geographic distribution, and bamboo harvesting by local people for commercial purposes place Bale monkeys at risk of extinction. To ensure the long-term survival of Bale monkeys, appropriate management action should be taken to conserve the species and the bamboo forests upon which it depends.

With group sizes sometimes >300 individuals, the Angolan black-and-white colobus (Colobus angolensis ruwenzorii) population in Nyungwe Forest, Rwanda is an intriguing exception to the tendency for folivores to live in smaller groups than expected relative to body size. Researchers have hypothesized that the unusually high quality of foliage at Nyungwe allows colobus there to avoid intragroup feeding competition, releasing constraints on the formation of large groups (Fimbel et al., 2001). We collected data on the activity and ranging patterns of a >300-member Nyungwe colobus group and compared our results to those from smaller groups in other black-and-white colobus (Colobus spp.) populations. Colobus at Nyungwe spent far more time feeding and moving (62%) and far less time resting (32%) than black-and-white colobus at any other site. The annual home range of the Nyungwe colobus was also many times larger (95% minimum convex polygon: 20.7 km 2 ; 95% fixed kernel: 24.4 km 2 ) than those for other populations. We terminated our research after the group engaged in an unprecedented migration among black-and-white colobus by moving 13 km south of their former range. Our results suggest that intragroup scramble competition may be more intense than originally believed within the large colobus groups at Nyungwe and that long periods of resource renewal may be necessary after a large colobus group passes through an area, thereby potentially helping to explain their wide ranging patterns. We discuss the socioecological convergence between the Nyungwe colobus and Chinese snub-nosed monkeys (Rhinopithecus spp.) and suggest directions for future research on the unique black-and-white colobus population at Nyungwe.

Nutritional factors are among the most important influences on primate food choice. We examined the influence of macronutrients, minerals, and secondary compounds on leaf choices by members of a foli-frugivorous population of eastern black-and-white colobus—or guerezas (Colobus guereza)—inhabiting the Kakamega Forest, Kenya. Macronutrients exerted a complex influence on guereza leaf choice at Kakamega. At a broad level, protein content was the primary factor determining whether or not guerezas consumed specific leaf items, with eaten leaves at or above a protein threshold of ca. 14% dry matter. However, a finer grade analysis considering the selection ratios of only items eaten revealed that fiber played a much greater role than protein in influencing the rates at which different items were eaten relative to their abundance in the forest. Most minerals did not appear to influence leaf choice, though guerezas did exhibit strong selectivity for leaves rich in zinc. Guerezas avoided most leaves high in secondary compounds, though their top food item (Prunus africana mature leaves) contained some of the highest condensed tannin concentrations of any leaves in their diet. Kakamega guerezas periodically traveled great distances to exploit rare foods (bark from exotic Myrtaceae trees and soil) outside their normal home ranges. Our results suggest that these journeys were driven by the fact that these rare foods contained exceptionally high sodium concentrations, a mineral believed to be deficient in the guereza's usual diet. Lastly, our results are consistent with the pattern established across other Paleotropical rain forests in which colobine biomass can be predicted by the protein-to-fiber ratio in mature leaves. Of the 8 rain forests for which the relevant data are available, Kakamega features the second highest mature leaf protein-to-fiber ratio as well as the second highest colobine biomass.

The Colobinae of Africa and Asia are perhaps best known for their specialized stomachs, which allow them to subsist on leafier and more chemically defended diets than most other primates (Kay and Davies, 1994; Oates et al., 1994). Many colobines are also renowned for their shy and indolent dispositions (Fashing, 2006), traits that make them particularly challenging study subjects. Nevertheless, research on colobines has led to some of the most exciting and contentious discoveries in the history of primate behavior and ecology. Over the past 3 decades, colobines have been at the center of an ongoing debate about the adaptive function of infant killing by males. After repeatedly witnessing male Hanuman langurs (Semnopithecus entellus) attempting to kill unrelated infants on Mount Abu, India in the early 1970s, Hrdy (1974, 1977) proposed the groundbreaking hypothesis that infanticide was part of a sexually selected alternative male reproductive strategy. In addition to inspiring a legion of impassioned detractors (Bartlett et al., 1993; Curtin and Dolhinow, 1979), Hrdy’s hypothesis stimulated a large body of research not only on primates, but also on other animals, from burying beetles to barn swallows to lions (van Schaik and Janson, 2000). Though the issue of infanticide’s adaptive function for male primates remains far from resolved today, at present the strongest evidence consistent with the

As the only extant graminivorous primate, gelada monkeys (Theropithecus gelada) offer unique insights into how hominins and other extinct primates with strong C4 isotopic signatures may have subsisted on graminoid-rich diets. Fossil Theropithecus species sharing a strong C4 signal (i.e., Theropithecus brumpti, Theropithecus darti, and Theropithecus oswaldi) have been reconstructed as predominantly graminivorous and potentially in ecological competition with contemporaneous hominins. However, inferring the breadth and variation of diet in these species (and therefore hominins) has proven problematic. Understanding how ecological variation within extant geladas impacts microwear and isotopic signatures may contribute to reconstructions of diet in fossil Theropithecus. Here, we build on a recent study at an ecologically intact tall grass ecosystem (Guassa, Ethiopia) that expanded the known diversity of gelada diets by demonstrating lower reliance on graminoids, greater consumption of forbs, and greater dietary species richness than previously described at disturbed sites. We used dental microwear texture analysis to explore how dietary variation among extant geladas may inform our understanding of the diets of fossil Theropithecus. First, we compared the dental microwear textures of geladas at Guassa to those of geladas from other sites. The microwear textures of geladas at Guassa exhibited more complexity, less anisotropy, and more variance in anisotropy and heterogeneity, reflecting the greater dietary diversity of Guassa geladas. Comparing microwear texture variables among this expanded gelada sample to those for T. brumpti, T. oswaldi, and T. darti yielded no significant differences. These results raise the intriguing possibility that data on how ecological variation and diet impact dental microwear and (possibly) isotopic signatures in extant geladas can be used to reconstruct the diets of extinct theropiths and, more broadly, hominins with strong C4 isotopic signatures. We conclude that extant gelada populations offer a powerful analog for inferring dietary variation among predominantly graminivorous fossil primates.

Mixed-species associations generally form to increase foraging success or to aid in the detection and deterrence of predators. While mixed-species associations are common among mammals, those involving carnivorous predators and potential prey species are seldom reported. On the Guassa Plateau, in the Ethiopian highlands, we observed solitary Ethiopian wolves (Canis simensis) foraging for rodents among grazing gelada monkey (Theropithecus gelada) herds. The tolerant and sometimes prolonged (> 1 h) associations contrasted with the defensive behaviors exhibited by geladas toward other potential predators. Ethiopian wolves spent a higher proportion of time foraging and preyed more successfully on rodents when among geladas than when alone, providing evidence that gelada herds increase the vulnerability of subterranean rodents to predation. Ethiopian wolves appear to habituate gelada herds to their presence through nonthreatening behavior, thereby foregoing opportunistic foraging opportunities upon vulnerable juvenile geladas in order to feed more effectively on rodents. For Ethiopian wolves, establishing proximity to geladas as foraging commensals could be an adaptive strategy to elevate foraging success. The novel dynamics documented here shed light on the ecological circumstances that contribute to the stability of mixed groups of predators and potential prey.

Formant dispersion, the average spacing, in Hz, between the resonant frequencies of a vocalization, has been predicted to provide honest information about signaler body size. Previous descriptions of black and white colobus monkey (Colobus guereza, ‘‘guereza’’) roars, however, suggest a formant dispersion that is far lower than expected for an animal its size, and could effectively exaggerate its body size. Nonetheless, recent research on red deer shows that even when the formant positions of vocalizations effectively exaggerate body size, they may still provide honest cues within a species. We investigate whether the frequency bands observed in the spectrograms of guereza roars represent formants, and whether roar formant dispersion and/or individual formants provide honest information about body size (specifically, body mass) relative to conspecifics, although perhaps not relative to other species. We document coordinated vertical movements in the frequency bands of guereza roars and show that these bands move independently of fundamental frequency, indicating that they represent formants. We show, for captive adult male guerezas, that signaler body mass significantly predicts roar formant dispersion, even for randomly selected calls. Body mass also predicts formants 2 and 3, but the relationships are not as strong as with formant dispersion. Our roar formant dispersion calculations predict a vocal tract length of approx. 29 cm, but anatomically determined guereza vocal tract length is much smaller: approx. 7–8 cm. Videotaped roars revealed no laryngeal movement during roars, but rather inflation of the subhyoid air sac. We measured the volume of this air sac (approx. 10 cm 3 ) and speculate that it may function in roars to exaggerate body size, relative to other species.

Prunus africana (Hook.f.) Kalkm. is a secondary forest canopy tree species that has been declining over much of its geographical range in sub-Saharan Africa during recent decades due to unsustainable harvesting of its bark for the international medicinal plant trade. One of the locations where the species is experiencing rapid mortality is Isecheno study site in the Kakamega Forest, Kenya where this study was conducted. Between 1997 and 2003, 21% of the P. africana (⩾10 cm DBH) at Isecheno died and an additional 9% experienced ⩾50% canopy dieback. However, scars from bark harvesting on P. africana were relatively small and scarred trees were not more likely to be dead or dying than unscarred trees, suggesting that bark exploitation is not causing P. africana mortality at Isecheno. Other possible causes that require further evaluation include disease, insect attack, nutrient deficiency, and/or climatic fluctuation. The poor regeneration of P. africana at Isecheno can likely be explained by the relative lack of recent disturbance coupled with the thick undergrowth layer at this site. P. africana mortality is of concern not only because the species is listed as Vulnerable by IUCN, but also because black and white colobus monkeys [Colobus guereza (Ruppell, 1835)] at Isecheno exploit it as their top food species and are particularly reliant on its leaves during times of `preferred' Moraceae fruit scarcity. The anticipated continued decline of P. africana may have adverse effects on C. guereza feeding habits, intergroup relations, and population density at Isecheno. Conservation of P. africana offers a formidable challenge since the species appears to require disturbance for regeneration, yet at sites where disturbance is occurring, P. africana is often a target of bark harvesters engaging in unsustainable levels of exploitation.

We conducted a study of spatial variation in tree community structure and composition in the Kakamega Forest of western Kenya. We compared the tree communities at two sites, Buyangu and Isecheno, separated by approximately 11 km of contiguous forest. All trees ‡15 cm d.b.h. were censused along transects covering 4.95 ha at Buyangu and 4.15 ha at Isecheno. The structure of the forest at the two sites was similar as mean d.b.h. was comparable and stem size class distribution did not differ significantly. However, species richness and stem density were both much higher at Buyangu. The disparity in stem density may be because of the greater abundance at Isecheno of a semi-woody undergrowth species, Brillantaisia nitens Lindau, believed to inhibit the establishment of tree seedlings. Floristic composition varied strikingly between sites, with 52% of the species occurring only at one site. Densities of those species present at both sites often differed markedly between sites. Potential sources of these intersite differences in floristic composition include small disparities in rainfall, soil composition, elevation, and temperature as well as past differences in anthropogenic disturbance and in large mammal distribution and abundance. Floristic differences between Buyangu and Isecheno appear to be at least partly responsible for the substantial dietary differences between redtail monkeys (Cercopithecus ascanius Audebert) at these sites.

Long-term studies of tree population dynamics play an important role in identifying the conservation needs of tropical forest ecosystems. We examined changes in tree population structure and composition over an 18-year period (1981–1999) in three plots located at the center of the Isecheno study site in the Kakamega Forest, Kenya, a forest with a history of logging and other anthropogenic disturbance. DBH size class distribution took the shape of an ‘inverse J’ curve in both 1981 and 1999 and did not differ significantly between the two study periods. Stem density increased significantly during the study with most of the increase occurring in the smallest stem size class (10–14 cm DBH). Nearly all of the most common species in 1981 remained among the most common in 1999, though the density of pioneer species decreased by 21% during the study. Our results suggest that forest in the study plots remained relatively undisturbed and in good condition over the study period. Forest in the plots also appeared still to be recovering from the selective logging of large trees that took place at Isecheno in the 1940s. In addition to our longitudinal study, we compared tree population parameters at three additional Isecheno sites spread over a distance of ∼1 km that have experienced different histories of disturbance: (i) a lightly human disturbed site (LHD), (ii) a heavily human disturbed site (HHD), and (iii) a cattle disturbed site (CD). While all three sites were selectively logged in the 1940s, the main signs of disturbance today are footpaths at the LHD site, tree stumps at the HHD site, and wide cattle paths at the CD site. Not surprisingly, of the disturbed sites, the LHD site was in the best condition. Trees at the HHD site exhibited extremely poor recruitment into the small size classes, a condition that can probably be attributed to human exploitation of small trees for poles. The CD site appeared to be at an earlier successional stage than the other disturbed sites with its low mean DBH, high overall stem density, and high pioneer species stem density. Browsing and trampling of vegetation by cattle may be the source of the light gaps that have led to the abundance of pioneer species at this site. We conclude that conservation measures applied to central Isecheno, including the establishment of a forest station nearby and ranger patrols, appear to have succeeded, but that the prognosis for the Kakamega Forest in general is bleak if protection efforts are not increased in other parts of the forest, where anthropogenic disturbance remains high. We also note the considerable variation in tree population structure and composition that can occur within a small area depending on the local history of disturbance.

Eastern black and white colobus monkeys, or guerezas (Colobus guereza), are among the few primate species that have traditionally been regarded as not being adversely affected by habitat degradation. This view was recently challenged by von Hippel et al. (2000) who, using data from short-term censuses in 1992 and 1998, reported a striking decline in guereza density over a six-year period of light to moderate habitat degradation at Isecheno study site in the Kakamega Forest, Kenya. In this paper, I present evidence from my own more intensive study during the same period that suggests that the guereza population at Isecheno is actually quite robust and may in fact be increasing. I provide evidence to suggest that the census methods adopted by von Hippel and his colleagues are prone to overestimating density and that the decline in guereza density that they reported probably did not occur. My study suggests that brief censuses based on group counts over a given area, even when conducted by multiple observers, are not sufficient for accurately determining primate distributions and densities in rainforest environments. Data on animal distribution and density play a critical role in the development of conservation strategies and it is therefore important that these data be relatively accurate if biologists are to make informed conservation decisions.