Variations in sexual behavior among capuchin monkeys function for conspecific mate recognition: a phylogenetic analysis and a new hypothesis for female proceptivity in tufted capuchins

Researchers of capuchin monkeys have noted stereotyped body postures, facial expressions, and vocalizations that accompany copulations in this genus. Notable variations in these sexual behaviors are observed across capuchin species. Although several hypotheses exist to explain variation in the duration and vigor of sexual behaviors across species, there is no proposed explanation for variation in the forms of these behaviors. I hypothesized that the forms of sexual behaviors function as recognition signals of conspecific mates. Such signals are adaptive when F1 hybrids exhibit reduced fitness compared with nonhybrid offspring. Recent evidence from nonprimate taxa supports the existence of species recognition signals during mating. Using newly observed sexual behaviors for Cebus albifrons and a recent phylogeny of capuchins, I found significant support for a key prediction of the conspecific mate recognition hypothesis: evolutionary changes in sexual behaviors were associated with speciation. Given the resultant best model for evolution of sexual behaviors, I reconstructed the ancestral pattern of sexual behaviors for extant capuchin species (genera Cebus and Sapajus). This reconstruction suggests that the extreme female proceptivity of tufted capuchin monkeys may function to increase female reproductive choices in the context of sperm-limited males (genus Sapajus).     

How different are robust and gracile capuchin monkeys? An argument for the use of sapajus and cebus

Capuchin monkey behavior has been the focus of increasing numbers of captive and field studies in recent years, clarifying behavioral and ecological differences between the two morphological types: the gracile and the robust capuchins (also referred to as untufted and tufted). Studies have tended to focus on the gracile species Cebus capucinus (fewer data are available for C. albifrons, C. olivaceus, and C. kaapori) and on Cebus apella, a name that has encompassed all of the robust capuchins since the 1960s. As a result, it is difficult to ascertain the variation within either gracile or robust types. The phylogenetic relationships between gracile and robust capuchins have also, until now, remained obscure. Recent studies have suggested two independent Pliocene radiations of capuchins stemming from a common ancestor in the Late Miocene, about 6.2 millions of years ago (Ma). The present-day gracile capuchins most likely originated in the Amazon, and the robust capuchins in the Atlantic Forest to the southeast. Sympatry between the two types is explained by a recent expansion of robust capuchins into the Amazon (ca. 400,000 years ago). Morphological data also support a division of capuchins into the same two distinct groups, and we propose the division of capuchin monkeys into two genera, Sapajus Kerr, 1792, for robust capuchins and Cebus Erxleben, 1777, for gracile capuchins, based on a review of extensive morphological, genetic, behavioral, ecological, and biogeographic evidence.     

Nonconceptive Sexual Behavior in Bonobos and Capuchins

Sexual behavior by infecundable females, and by same-sex and adult-immature dyads, occurs in wild and captive bonobos (Pan paniscus). Proposed functions of these behaviors, in social primates generally, include practice, paternity confusion, exchange, and communication as well as appeasement. We used this framework to interpret and to compare observations of sexual behavior in a captive bonobo group and a wild white-faced capuchin (Cebus capucinus) group. In both species, (a) sexual behavior was no more frequent in cycling females than in pregnant or lactating females and (b) same-sex and adult-immature dyads engaged in as much mounting or genitogenital contact as adult heterosexual dyads did. The species differed in that (a) bonobos engaged in sexual behavior 65 times as frequently as capuchins, (b) only bonobos engaged in sexual contact other than ventrodorsal mounting during focal observation, and (c) bonobo sexual contact was concentrated most heavily in socially tense situations in adult female–female dyads, whereas capuchin sexual contact was concentrated most heavily in socially tense situations in adult male–male dyads. These data and published literature indicate that (a) practice sex occurs in both species, (b) paternity confusion may be a current function of C. capucinus nonconceptive sex, (c) exchange sex remains undemonstrated in capuchins, and (d) communication sex is more important to members of the transferring sex—female bonobos and male capuchins—than to members of the philopatric sex.     

Interaction Between Capuchins and Coatis: Nonagonistic Behaviors and Lack of Predation

We compare the nature of capuchin-coati interactions by Cebus apella in 2 populations under semifree-ranging and wild conditions. We report a similar pattern of interaction at both sites, in spite of their ecological differences. Most frequent capuchin behaviors toward coatis were agonistic, but we noted no predation. Contrarily, the monkeys also exhibited nonagonistic behaviors, such as play and grooming. As tufted capuchins predate other mammalian species, and as the subjects were aggressive towards competitor species, showing their belligerent temperament, we believe the lack of predation can be attributed to 2 different ecological contigencies – the absence of coati pups in a period of food shortage, and the cost of dealing with a dangerous adult coati where other rich resources were available–and also, perhaps, to different traditions in capuchin behavior towards coatis, established via intraspecific social learning.     

Compound grips in tufted capuchin monkeys (Sapajus spp and Sapajus libidinosus)

An experimental study with captive individuals and study of video recordings of wild monkeys explored whether and how tufted capuchin monkeys use onehand to hold one or more objects with multiple grips (compound grips). A task designed to elicit compound grip was presented to five captive tufted capuchin monkeys (Sapajus spp). The monkeys held one to four balls in onehand and dropped the balls individually into a vertical tube. Multiple simple grips and independent digit movements enabled separate control of multiple objects in one hand. Monkeys always supported the wrist on the horizontal edge of the tube before releasing the ball. Increasing the number of balls decreased the likelihood that the monkeys managed the task. Wild bearded capuchins (Sapajus libidinosus) used compound grips spontaneously to store multiple food items. Compound grips have been described in macaques, gorillas, chimpanzees, and humans, and now in a New World primate. We predict that any primate species that exhibits precision grips and independent digit movement can perform compound grips. Our findings suggest many aspects of compound grip that await investigation.     

Experimental field study of problem-solving using tools in free-ranging capuchins (Sapajus nigritus, formerly Cebus nigritus)

Some populations of capuchins are reported to use tools to solve foraging problems in the wild. In most cases, this involves the act of pounding and digging. The use of probing tools by wild capuchins is considerably less common. Here we report on the results of an experimental field study conducted in southern Brazil designed to examine the ability of wild black-horned capuchins (Sapajus nigritus) to use a wooden dowel as a lever or a probe to obtain an embedded food reward. A group of eight capuchins was presented with two experimental platforms, each housing a clear Plexiglas box containing two bananas on a shelf and four inserted dowels. Depending on the conditions of the experiment, the capuchins were required either to pull (Condition I) or push (Conditions II and III) the dowels, in order to dislodge the food reward from the shelf so that it could be manually retrieved. In Condition I, four individuals spontaneously solved the foraging problem by pulling the dowels in 25% (72/291) of visits. In Conditions II and III, however, no capuchin successfully pushed the dowels forward to obtain the food reward. During these latter two experimental conditions, the capuchins continued to pull the dowels (41/151 or 27% of visits), even though this behavior did not result in foraging success. The results of these field experiments are consistent with an identical study conducted on wild Cebus capucinus in Costa Rica, and suggest that when using an external object as a probe to solve a foraging problem, individual capuchins were able to rapidly learn an association between the tool and the food reward, but failed to understand exactly how the tool functioned in accomplishing the task. The results also suggest that once a capuchin learned to solve this tool-mediated foraging problem, the individual persisted in using the same solution even in the face of repeated failure (slow rate of learning extinction).     

Tool use in Cebus

This paper summarizes early anecdotal information and systematic studies of tool use in capuchin monkeys (Cebus spp.). Tool use in capuchins is neither context specific nor stereotyped. The success of capuchins in using tools and in exploiting a variety of food resources in the wild derives from several factors: their manipulative abilities, interest in external objects and a tendency to explore the environment. In using tools, capuchins are similar to apes and more proficient than other monkey species. A cognitive approach indicates, however, that (in contrast with chimpanzees) they never develop an understanding of the requirements of the tool tasks presented.     

Predictors of Parasitism in Wild White-Faced Capuchins (Cebus capucinus)

Parasite infections in wildlife are influenced by many factors including host demography, behavior and physiology, climate, habitat characteristics, and parasite biology and ecology. White-faced capuchins (Cebus capucinus) host a suite of gastrointestinal and pulmonary parasites, yet the mechanisms affecting host susceptibility and parasite transmissibility have not been examined in this host species. We used the information-theoretic approach (Akaike’s information criterion) and traditional null-hypothesis testing to determine which host characteristics, behaviors, or environmental factors affected the presence of two prevalent capuchin parasites (Filariopsis barretoi and Strongyloides sp.) as well as parasite species richness in four groups of wild capuchins from September 2007 to January 2008 and January to August 2009. Older capuchins were more likely to be infected with Filariopsis barretoi and had higher parasite species richness. Age-biased nematode infections may stem from age differences in capuchin behavior and physiology while high species richness likely results from long- term exposure to numerous parasite species. Infections with Strongyloides sp. were more likely to occur in the dry season when capuchins often descend to the forest floor to drink from terrestrial water sources, potentially increasing their risk of infection from soil-borne larvae. Capuchin behaviors were poor predictors of parasitism, as were female rank, host sex, home range size, and habitat quality. Many of our results were atypical for primate parasitology, suggesting that host–parasite interactions, and subsequently infection risk, may differ in highly seasonal habitats such as tropical dry forests where these monkeys occur.     

Effects of gut passage,feces, and seed handling on latency and rate of germination in seeds consumed by capuchins (Cebus capucinus)

One of the key measures of the effectiveness of primary seed dispersal by animals is the quality of seed dispersal (Schupp: Plant Ecol 107/108 [1993] 15–29). We present data on quality of seed dispersal by two groups of white‐faced capuchins (Cebus capucinus) in Costa Rica to test the hypothesis that capuchin seed handling results in effective primary dispersal for some fruit species they consume. We examined seed handling for 27 plant species, and germination rates of 18 species consumed by capuchins. For five of the most commonly swallowed seed species, we determined germination rates and average time to germination (latency) for seeds ingested and defecated by capuchins and compared these to seeds removed directly from fruit and planted. For the same five species, we compared germination rates and latency for passed seeds planted in capuchin feces to those cleaned of feces and planted in soil. For three of five species, differences in proportion of germinated seeds were significantly higher for gut passed seeds than for controls. For four of five species, germination latency was significantly faster for gut passed seeds than for controls. Feces had either no effect on seed germination rate or precluded germination. Data presented here support the hypothesis that white‐faced capuchins are effective primary dispersers. Am J Phys Anthropol 2009. © 2009 Wiley‐Liss, Inc.     

Physical properties of palm fruits processed with tools by wild bearded capuchins (Cebus libidinosus)

Habitually, capuchin monkeys access encased hard foods by using their canines and premolars and/or by pounding the food on hard surfaces. Instead, the wild bearded capuchins (Cebus libidinosus) of Boa Vista (Brazil) routinely crack palm fruits with tools. We measured size, weight, structure, and peak-force-at-failure of the four palm fruit species most frequently processed with tools by wild capuchin monkeys living in Boa Vista. Moreover, for each nut species we identify whether peak-force-at-failure was consistently associated with greater weight/volume, endocarp thickness, and structural complexity. The goals of this study were (a) to investigate whether these palm fruits are difficult, or impossible, to access other than with tools and (b) to collect data on the physical properties of palm fruits that are comparable to those available for the nuts cracked open with tools by wild chimpanzees. Results showed that the four nut species differ in terms of peak-force-at-failure and that peak-force-at-failure is positively associated with greater weight (and consequently volume) and apparently with structural complexity (i.e. more kernels and thus more partitions); finally for three out of four nut species shell thickness is also positively associated with greater volume. The finding that the nuts exploited by capuchins with tools have very high resistance values support the idea that tool use is indeed mandatory to crack them open. Finally, the peak-force-at-failure of the piassava nuts is similar to that reported for the very tough panda nuts cracked open by wild chimpanzees; this highlights the ecological importance of tool use for exploiting high resistance foods in this capuchin species.     

Social Aspects of Fur-rubbing in <Emphasis Type="Italic">Cebus capucinus</Emphasis> and <Emphasis Type="Italic">C. apella</Emphasis>

Capuchins rub particular plant materials into their pelage, a behavior for which most authors have proposed a medicinal function (Baker in American Journal of Primatology 38:263–270, 1996, Baker, M. (1998). Fur Rubbing as Evidence for Medicinal Plant Use by Capuchin Monkeys (Cebus capucinus): Ecological, Social, and Cognitive Aspects of the Behavior. Dissertation thesis. University of California Riverside; DeJoseph et al. in Journal of the American Academy of Dermatology 46:924–925, 2002). Individuals fur-rub solitarily or in groups, but researchers have not conducted studies to understand the differences. We investigated the link between the form of fur-rubbing and other social variables in 2 capuchin species. We supplied 2 captive groups —white-faced capuchins and tufted capuchins— with citrus fruit and onions and explored the behavioral processes and social aspects underlying the activity. We documented the occurrence, number of participants, and effect of recruitment behaviors in fur-rubbing subgroups. We investigated the role of kinship, affiliation, and dominance relationships in accounting for fur-rubbing groups. There is a significant difference in the form of fur-rubbing between white-faced and tufted capuchins. White-faced capuchins fur-rubbed mainly in subgroups and performed a particular behavior to recruit prospective participants, whereas tufted capuchins fur-rubbed mainly alone, and showed no particular motivation to be joined by other group members. White-faced capuchins could fur-rub together frequently, whatever their degree of kinship, affiliation, or dominance interval. In tufted capuchins, fur-rubbing appeared to be significantly affected by kinship and dominance.     

The relationship between locomotor behavior and limb morphology in brown (Cebus apella) and weeper (Cebus olivaceus) capuchins

This study is a comparison of locomotor behavior and postcranial form in two species of capuchin monkey, the brown capuchin (Cebus apella), and the weeper capuchin (Cebus olivaceus). Behavioral data from groups of wild C. apella and C. olivaceus in Guyana were collected during the period of December 1999 through November 2000. Postcranial variables including 40 measurements and three indices were taken from 43 adult and subadult specimens of C. apella and 14 adult and subadult specimens of C. olivaceus housed in American museums, as well as two wild-caught adult specimens of C. olivaceus from the Georgetown Zoo in Guyana. The results of this study indicate that these two capuchins exhibit similar patterns of locomotor behavior, but that there are important differences in how they move through their homerange, particularly with respect to quadrupedalism. These differences in behavior are reflected in their postcranial morphology and can be related to differences in foraging strategies. This study provides an example of the importance of using more exclusive categories of quadrupedal behaviors when comparing closely related arboreal quadrupeds, as well as an alternative explanation for some of the postcranial features of C. apella that may relate to foraging postures and foraging strategy rather than traditionally categorized patterns of locomotor behavior.     

The Time Frame of Partner Choice in the Grooming Reciprocation of Cebus apella

Recent theoretical and experimental studies argued that reciprocity is constrained by the cognitive limitations of most animals and that, when reciprocation occurs, it should necessarily be short term. In this study, we examined the time frame of partner choice in the reciprocal grooming of captive female tufted capuchin monkeys ( Cebus apella ). Female capuchins groomed preferentially those individuals that overall groomed them most. Tufted capuchins did sometimes reciprocate grooming immediately. We quantified the time course and probability of immediate reciprocation, and excluded from the analysis cases of immediate reciprocation. We then showed that, even excluding immediate reciprocation, female capuchins still preferred to groom those individuals that groom them most. Our results show that partner choice is not necessarily based on immediate reciprocation and suggest that capuchins are able to reciprocate over longer time frames. These findings argue against the hypothesis that long-term reciprocation is absent in species lacking sophisticated cognitive abilities. We suggest that reciprocal altruism over long time frames relies on a system of emotional bookkeeping.     

Field Anesthesia and Health Assessment of Free-ranging <Emphasis Type="Italic">Cebus capucinus</Emphasis> in Panama

Health and disease are critical factors for understanding primate evolution and for developing effective conservation and management strategies. However, comprehensive health assessments of wild primate populations are rare, in part because of the difficulty and risk of chemically immobilizing subjects to obtain the necessary biological samples. We report here the results of a health assessment, as well as the methods and drug dosages used to capture white-faced capuchins (Cebus capucinus) on Barro Colorado Island, Panama. We captured and measured 24 capuchins as part of an ongoing radiotelemetry study, and collected biological samples from 9 of them for a comprehensive health survey. Telazol® was very effective for immobilizing and capturing capuchins, although the doses we used were higher than those recommended for captive capuchins. High Telazol doses immobilized individuals quickly, ensuring that we were able to find and recover the sedated monkeys. The capuchins were generally in good condition, and had few ecto-, hemo-, or intestinal parasites. However, all but 1 of the adults had substantial dental abnormalities. In addition, 1 juvenile had indeterminate genitalia that we believe to be the result of hypospadias. Seven of the capuchins tested positive for exposure to Herpesvirus tamarinus and all individuals tested positive for exposure to Cebus cytomegalovirus. Hematology, serum chemistry, and plasma mineral levels from the wild individuals were, for the most part, comparable to those recorded for captive Cebus capucinus, and contribute to establishing baseline health values for the species.     

Positional behavior and substrate use in wild adult bearded capuchin monkeys (Sapajus libidinosus)

Natural selection for positional behavior (posture and locomotion) has at least partially driven the evolution of anatomical form and function in the order Primates. Examination of bipedal behaviors associated with daily activity patterns, foraging, and terrestrial habitat use in nonhuman primates, particularly those that adopt bipedal postures and use bipedal locomotion, allows us to refine hypotheses concerning the evolution of bipedalism in humans. This study describes the positional behavior of wild bearded capuchins (Sapajus libidinosus), a species that is known for its use of terrestrial substrates and its habitual use of stones as tools. Here, we test the association of terrestrial substrate use with bipedal posture and locomotion, and the influence of sex (which co‐varies with body mass in adults of this species) on positional behavior and substrate use. Behavior and location of 16 wild adult bearded capuchins from two groups were sampled systematically at 15 s intervals for 2 min periods for 1 year (10,244 samples). Despite their different body masses, adult males (average 3.5 kg) and females (average 2.1 kg) in this study did not differ substantially in their positional behaviors, postures, or use of substrates for particular activities. The monkeys used terrestrial substrates in 27% of samples. Bipedal postures and behaviors, while not a prominent feature of their behavior, occurred in different forms on the two substrates. The monkeys crouched bipedally in trees, but did not use other bipedal postures in trees. While on terrestrial substrates, they also crouched bipedally but occasionally stood upright and moved bipedally with orthograde posture. Bearded capuchin monkeys' behavior supports the suggestion from anatomical analysis that S. libidinosus is morphologically better adapted than its congeners to adopt orthograde postures.     

The ecological role of the prehensile tail in white-faced capuchins (Cebus capucinus).

Prehensile tails appear to have evolved at least twice in platyrrhine evolution. In the atelines, the tail is relatively long and possesses a bare area on the distal part of its ventral surface that is covered with der-matoglyphs and richly innervated with Meissner's corpuscles. In contrast, the prehensile tail of Cebus is relatively short, fully haired, and lacks specialized tactile receptors. Little is currently known regarding tail function in capuchins, and whether their prehensile tail serves a greater role in feeding or traveling. In this paper we examine patterns of positional behavior, substrate preference, and tail use in wild white-faced capuchins (Cebus capucinus) inhabiting a wet tropical forest in northeastern Costa Rica. Observational data were collected over the course of 3 months on adult capuchins using an instantaneous focal animal time sampling technique. Differences in the frequency and context of tail use, and the estimated amount of weight support provided by the tail relative to other appendages during feeding/foraging and traveling were used as measures of the ecological role of this specialized organ in capuchin positional behavior. During travel, quadrupedal walking, leaping, and climbing dominated the capuchin positional repertoire. The capuchin tail provided support in only 13.3% of travel and was principally employed during below branch locomotor activities. In contrast, tail-assisted postures accounted for 40.6% of all feeding and foraging records and occurred primarily in two contexts. The tail was used to suspend the individual below a branch while feeding, as well as to provide leverage and weight support in above-branch postures associated with the extraction of prey from difficult to search substrates. A comparison of tail use in Cebus, with published data on the atelines indicates that both taxa possess a grasping tail that is capable of supporting the animal's full body weight. In capuchins and howling monkeys, the tail appears to be used more frequently and serves a greater weight-bearing role during feeding than during traveling. In Ateles, and possibly Brachyteles, and Lagothrix, however, the prehensile tail serves a dual role in both feeding and forelimb suspensory locomotion. Additional relationships between white-faced capuchin feeding, positional behavior, extractive foraging techniques, and prehensile tail use are discussed.     

Consistency of hand preference across low-level and high-level tasks in capuchin monkeys (Cebus apella)

Numerous studies investigating behavioral lateralization in capuchins have been published. Although some research groups have reported a population-level hand preference, other researchers have argued that capuchins do not show hand preference at the population level. As task complexity influences the expression of handedness in other primate species, the purpose of this study was to collect hand preference data across a variety of high- and low-level tasks to evaluate how task complexity influences the expression of hand preference in capuchins. We tested eleven captive brown capuchin monkeys (Cebus apella) to determine if they show consistent hand preferences across multiple high- and low-level tasks. Capuchins were expected to display high intertask consistency across the high-level tasks but not the low-level tasks. Although most individuals showed significant hand preferences for each task, only two of the high-level tasks that involved similar hand motions were significantly positively correlated, indicating consistency of hand preference across these tasks only. None of the tasks elicited a group-level hand preference. High-level tasks elicited a greater strength of hand preference than did low-level tasks. No sex differences were found for the direction or strength of hand preference for any task. These results contribute to the growing database of primate laterality and provide additional evidence that capuchins do not display group-level hand preferences.     

Tail growth tracks the ontogeny of prehensile tail use in capuchin monkeys (Cebus albifrons and C. apella)

Physical anthropologists have devoted considerable attention to the structure and function of the primate prehensile tail. Nevertheless, previous morphological studies have concentrated solely on adults, despite behavioral evidence that among many primate taxa, including capuchin monkeys, infants and juveniles use their prehensile tails during a greater number and greater variety of positional behaviors than do adults. In this study, we track caudal vertebral growth in a mixed longitudinal sample of white-fronted and brown capuchin monkeys (Cebus albifrons and Cebus apella). We hypothesized that young capuchins would have relatively robust caudal vertebrae, affording them greater tail strength for more frequent tail-suspension behaviors. Our results supported this hypothesis. Caudal vertebral bending strength (measured as polar section modulus at midshaft) scaled to body mass with negative allometry, while craniocaudal length scaled to body mass with positive allometry, indicating that infant and juvenile capuchin monkeys are characterized by particularly strong caudal vertebrae for their body size. These findings complement previous results showing that long bone strength similarly scales with negative ontogenetic allometry in capuchin monkeys and add to a growing body of literature documenting the synergy between postcranial growth and the changing locomotor demands of maturing animals. Although expanded morphometric data on tail growth and behavioral data on locomotor development are required, the results of this study suggest that the adult capuchin prehensile-tail phenotype may be attributable, at least in part, to selection on juvenile performance, a possibility that deserves further attention.     

Responses to a snake model in captive crab-eating macaques (Macaca fascicularis) and captive tufted capuchins (Cebus apella)

The responses to a model snake in captive crab-eating macaques (Macaca fascicularis) and captive tufted capuchins (Cebus apella) were investigated. In both species the amount of fear behavior was higher in the presence of the model than during baseline conditions. Unlike the macaques, in the capuchins the frequency of these behaviors decreased across trials. In the two species the amount of explorative and manipulative behaviors and the use of space were also different. Unlike macaques, all capuchins manipulated the objects available in the testing room, and three subjects contacted the apparatus by using objects. Macaques did not show significant preferences for any particular part of the testing room. In both conditions, capuchins used the floor more than macaques did. Further, capuchins increased the use of the floor across experimental trials. Latency to reach the floor was higher in macaques than in capuchins. When on the floor, capuchins spent most of the time close to the snake apparatus. It is proposed that the behavioral differences between capuchins and macaques in the responses to a potential predator indicate that capuchins have a greater propensity to explore and to contact the novel stimulus directly, or by means of objects, than macaques do. These tendencies may lead to the exploitation of novel features in the environment.     

High density of white-faced capuchins (Cebus capucinus) and habitat quality in the Taboga Forest of Costa Rica

Across the globe, primates are threatened by human activities. This is especially true for species found in tropical dry forests, which remain largely unprotected. Our ability to predict primate abundance in the face of human activity depends on different species' sensitivities as well as on the characteristics of the forest itself. We studied plant and primate distribution and abundance in the Taboga Forest, a 516-ha tropical dry forest surrounded by agricultural fields in northwestern Costa Rica. We found that the density of white-faced capuchins (Cebus capucinus) at Taboga is 2–6 times higher than reported for other long-term white-faced capuchin sites. Using plant transects, we also found relatively high species richness, diversity, and equitability compared with other tropical dry forests. Edge transects (i.e., within 100 m from the forest boundary) differed from interior transects in two ways: (a) tree species associated with dry forest succession were well-established in the edge and (b) canopy cover in the edge was maintained year-round, while the interior forest was deciduous. Sighting rates for capuchins were higher near water sources but did not vary between the edge and interior forest. For comparison, we also found the same to be true for the only other primate in the Taboga Forest, mantled howler monkeys (Alouatta palliata). Year-round access to water might explain why some primate species can flourish even alongside anthropogenic disturbance. Forest fragments like Taboga may support high densities of some species because they provide a mosaic of habitats and key resources that buffer adverse ecological conditions.