RESUMO
Masturbation is part of the natural behavioral repertoire of primates, with visual sexual stimuli known to trigger this behavior. Here, we report masturbation events triggered by visual sexual stimulus (VSS) in the South American primate Sapajus libidinosus. We observed a multi-male multi-female captive colony of 17 bearded capuchins between January and October 2014. Over this period, we registered 11 copulation events, 68 attempt copulations, and five masturbation events. The same low-ranking male (named Fu) performed all masturbation events. Fu directly looked at other individuals engaged in sexual displays while he masturbated in three events. The masturbation events associated with VSS lasted up to 2 min and 40 s. Our observations show that VSS can trigger masturbation in capuchin monkeys. The low hierarchy rank of the male, and the consequent lack of mating opportunities in the multi-male multi-female recently formed group in captivity, may have prompted the masturbation events.
Assuntos
Cebinae , Masturbação , Animais , Masculino , Feminino , Humanos , Cebus , Comportamento SexualRESUMO
There is wide variability in primate behavior and ecology. Understanding how frugivorous primates behave under different habitat fragmentation levels is key for effective conservation and management of species and their habitats. We evaluated the seasonality in activity budget, diet, and ranging behavior of two groups of Endangered Coimbra-Filho's titi monkeys (Callicebus coimbrai). One group inhabited a 14-ha forest fragment, whereas the other lived in a 522-ha fragment. We measured the monthly density of trees and lianas available as food sources over 8 months. We also collected behavioral and group location data every 5 min, from dawn to dusk, using the scan sampling method. The two forest fragments differed seasonally in the number of fruiting food-resource available. In the 14-ha fragment, we found that the time spent by titi monkeys feeding, foraging, resting, and traveling differed seasonally. In the 522-ha fragment, titi monkeys exhibited seasonal differences in time spent sleeping, socializing, foraging, and revisiting food sources. In both titi monkey groups, diets varied seasonally. Our findings indicate that Coimbra-Filho's titi monkeys can exhibit behavioral flexibility in their activity budgets, diets, and movement patterns. Such flexibility is important for this species to survive in fragmented habitats and may be linked to three key factors: species-specific resource availability, plant species diversity, and the vegetation structure of each forest fragment.
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Callicebus , Pitheciidae , Animais , Dieta/veterinária , Ecossistema , Comportamento Alimentar , HaplorrinosRESUMO
Natural Sapajus libidinosus populations are in continuous decline due to fragmentation, habitat loss, and the illegal pet trade. They live in Caatinga scrub forests, which already lost over 50% of their original cover. The lack of studies on S. libidinosus population genetics means that we do not know how they are being affected by this striking habitat loss and other anthropogenic disturbances. Polymorphic markers are not available for the study of S. libidinosus diversity and population genetics. Thus, here we aimed to test the transferability of 14 microsatellite markers to S. libidinosus. These microsatellites were previously isolated from Cebus capucinus (white-faced capuchin), species belonging to the same subfamily (Cebinae) as the study species. We found that six of the tested microsatellite markers (tetra-nucleotide) were cross-amplified in our target species. All loci were polymorphic. The number of alleles varied from 4 to 7, and the expected heterozygosity ranged from 0.588 to 0.869. The microsatellite markers transferred to S. libidinosus and characterised in our study will be valuable tools to evaluate the genetic variability of both wild and captive populations. They will considerably reduce the costs of microsatellite isolations, helping to prioritise currently limited research and conservation budgets in Brazil.
Assuntos
Cebinae , Animais , Brasil , Repetições de Microssatélites/genética , FilipinasRESUMO
Birds can solve many cognitive tasks that were previously only solved by primates, implying that their cognitive ability is far greater than expected. Here, we investigated the ability of blue-fronted amazon parrots in solving the pebble-and-seed and the multi-access-box paradigms, two ecologically relevant cognitive tasks varying in complexity and required skills to solve. We also investigated whether laterality, sex and housing conditions influenced problem-solving capacity. We tested 14 adults kept in captivity and 27 reintroduced adults. Here, we present evidence of laterality for the species, showing right-footed, left-footed and ambidextrous individuals. Left-footed animals were more successful than the right-footed animals in the pebble-and-seed test. There was no sex difference in the problem-solving capacity of the blue-fronted amazon parrots for both pebble-and-seed and multi-access-box paradigms. Eleven captive animals were successful in at least one of the four multiple-access-box possible solutions. Four reintroduced individuals were successful in at least one of the multiple-access-box possible solutions. Only two captive animals and one reintroduced animal succeeded to solve more than one of the four multiple-access-box solutions. The average success rate of the pebble-and-seed test was 88.16% ex situ and 86.58% in situ, with individual variation in test-solving ability. Our study shows that unlike laterality, sex was not determinant in blue-fronted amazon parrots' problem-solving ability. The blue-fronted amazon parrots have the visual discrimination skills needed for the pebble-and-seed task solution, and the motor skills for beak-foot coordination and potentially understanding of complex spatial relationships required for the string-pulling task, the multi-access-box solution achieved by most of the animals. Our results increased the knowledge of the cognitive ability of parrots, a group which lacked extensive cognition data.
Assuntos
Amazona , Papagaios , Animais , Compreensão , Resolução de Problemas , Caracteres SexuaisRESUMO
Defensive secretions of millipedes are remarkable for containing toxic quinones known to efficiently repell hematophagous arthropods. Here we show that Endangered blonde capuchin monkeys make use of such secretions. We (i) describe the anointing behavior performed by the monkeys (ii) identify the millipede species used in the process (iii) describe the volatile chemical composition of its secretion. The blonde capuchin monkeys selectively searched for millipedes hidden under the ground. We observed three bouts of anointing behavior, performed by 13 individuals of all age classes (from adults to independent infants), both solitarily (1 event) and socially (10 events). The only millipede species used by the monkeys is an undescribed species of the genus Poecilocricus (Spirobolida, Rhinocricidae). The volatile chemical composition of the secretions was predominantly comprised of a mixture of benzoquinones and hydroquinones. The social nature of the behavior and time of the observations (mosquito season), suggest that social bonding and mosquito avoidance is linked to the anointing behavior of the monkeys.
Assuntos
Artrópodes/metabolismo , Comportamento Animal/efeitos dos fármacos , Benzoquinonas/farmacologia , Cebus/fisiologia , Comportamento Alimentar/efeitos dos fármacos , Hidroquinonas/farmacologia , Animais , Artrópodes/química , Benzoquinonas/isolamento & purificação , Hidroquinonas/isolamento & purificação , Comportamento SocialRESUMO
Vocalizations are often used by animals to communicate and mediate social interactions. Animals may benefit from eavesdropping on calls from other species to avoid predation and thus increase their chances of survival. Here we use both observational and experimental evidence to investigate eavesdropping and how acoustic signals may mediate interactions between two sympatric and endemic primate species (common marmosets and blonde capuchin monkeys) in a fragment of Atlantic Rainforest in Northeastern Brazil. We observed 22 natural vocal encounters between the study species, but no evident visual or physical contact over the study period. These two species seem to use the same area throughout the day, but at different times. We broadcasted alarm and long distance calls to and from both species as well as two control stimuli (i.e., forest background noise and a loud call from an Amazonian primate) in our playback experiments. Common marmosets showed anti-predator behavior (i.e., vigilance and flight) when exposed to blonde capuchin calls both naturally and experimentally. However, blonde capuchin monkeys showed no anti-predator behavior in response to common marmoset calls. Blonde capuchins uttered long distance calls and looked in the direction of the speaker following exposure to their own long distance call, whereas they fled when exposed to their own alarm calls. Both blonde capuchin monkeys and common marmosets showed fear behaviors in response to the loud call from a primate species unknown to them, and showed no apparent response to the forest background noise. Common marmoset responses to blonde capuchin calls suggests that the latter is a potential predator. Furthermore, common marmosets appear to be eavesdropping on calls from blonde capuchin monkeys to avoid potentially costly encounters with them.
Assuntos
Callithrix/fisiologia , Cebinae/fisiologia , Vocalização Animal , Comunicação Animal , Animais , Brasil , Callithrix/psicologia , Cebinae/psicologia , Medo , Floresta ÚmidaRESUMO
To reduce the vulnerability of their small body size, common marmosets live in large and cohesive social groups. Thus, we hypothesized that in order to compensate for small body size and predation risk, individuals of common marmosets will stay gathered rather than scattered when foraging for eggs and/or nestling birds. Furthermore, in order to avoid costly injuries and eventual predation risks, for both sides, the majority of interactions among common marmosets and small birds will not involve direct physical contact. The study was developed in a small fragment of Atlantic Forest in the northeast of Brazil. We recorded a total of 115 interactions between common marmosets (Callithrix jacchus) with 7 different bird species. As expected, agonistic interactions were significantly more frequent when the marmosets were gathered. Also, most agonistic interactions by the birds toward common marmosets involved overflights without physical contact. Apparently, the set of avoidance behavior leads to a reduced predation risk for both sides. It appears that dispersed marmosets do not represent an imminent threat that justifies an agonistic reaction by the birds as the latter appear to avoid exposing themselves to unnecessary danger during agonistic interactions, especially when the marmosets are gathered.
Assuntos
Comportamento Agonístico , Aves , Callithrix/psicologia , Cadeia Alimentar , Comportamento Predatório , Animais , Brasil , Feminino , Masculino , Floresta ÚmidaRESUMO
The interaction between native fleshy-fruit plants and introduced fruit consumers contributes to the dynamics of highly fragmented environments. Such interactions can occur through pollination and seed dispersal. Here, we investigated the potential of seed dispersing by a non-native primate, the squirrel monkey (Saimiri sciureus), in an urban Atlantic forest fragment in north-eastern Brazil. Fleshy fruits from non-native plants were preferentially exploited by the squirrel monkeys. We measured 147 seeds (width and length) from 20 of 106 faecal samples. The dispersed seeds were from five plant species (four families). We found a positive correlation between the size of seeds found in faecal samples with their availability in the habitat. Only one seed was found visually damaged after passage through the squirrel monkeys' guts. The defecated seeds were uniformly distributed (variance to mean ratio index) in the home range of squirrel monkeys, and there was a lack of specific latrines (i.e., habitat preference for defecation). Our data provide evidence that non-native S. sciureus may in be (i) acting as a potential seed disperser of native plants in the Atlantic forest fragment, (ii) contributing to the ecological role of native frugivores, and (iii) potentially contributing to the regeneration process of the highly degraded study site.
Assuntos
Biodiversidade , Dieta , Florestas , Saimiri/fisiologia , Dispersão de Sementes , Animais , Brasil , Cidades , Fezes/química , Herbivoria , Espécies Introduzidas , Sementes/classificaçãoRESUMO
Areas holding primates in semi-captivity conditions represent an excellent opportunity for collecting data on rare, little known, and endangered taxa, contributing with insightful information to help in their conservation. Here, we present information on the activity budget and social interactions of the elusive gray woolly monkeys, Lagothrix lagotricha cana, in an ex situ conservation area in central Amazonia. We studied the behavior of 18 semi-captive individuals through instantaneous scan and focal animal samplings during 4 months in the wet season. The most frequent activity registered was resting (45%). The remaining time was dedicated to foraging (29%), travelling (23%), social interactions (3%), and self-grooming (1%). Resting and travelling time may be correlated to fruit availability in the area through different seasons. Huddling was the most frequent social interaction, being more common from young individuals toward adult females, which may be associated with breastfeeding. Playing was more common among young males. This activity prepares them to defend themselves from possible attacks and allows them to develop their role in the social group, as future adult males. Aggression was most frequent among adults, primarily from males toward females, likely to demonstrate their dominance over females. Social grooming occurred predominantly from mother to offspring. This interaction can reduce the risk of young predation, directly increasing the female reproductive success. Our data not only add to our understanding of the sociality and behaviors of the genus Lagothrix, but may also serve as a tool to identify environments that support an adequate activity budget for these monkeys. Zoo Biol. 36:21-29, 2017. © 2016 Wiley Periodicals, Inc.
Assuntos
Atelinae/fisiologia , Comportamento Animal/fisiologia , Atividade Motora/fisiologia , Comportamento Social , Animais , Brasil , Conservação dos Recursos Naturais , Feminino , Masculino , Jogos e Brinquedos , Fatores SexuaisRESUMO
OBJECTIVES: Fruit husks are rarely uniformly hard, varying in penetrability via sulci and changes in thickness. We tested whether a hard-food specialist primate i) bites randomly on food fruit husk surfaces to access seeds, or ii) selects areas most easily penetrated by canines. We consider this would occur so as to minimize deployed mechanical force, energetic expenditure and risk of dental breakage when feeding. METHODS: A sulcus is the natural line of weakness where a dehiscent fruit breaks open. Using fruits dentally opened for seeds by golden-back uacaris (Cacajao ouakary) we: 1) analysed bite mark distribution on surface of four fruits types (hard-with-sulcus, soft-with-sulcus, hard-no-sulcus, soft-no-sulcus); 2) quantified the force needed to penetrate hard and soft fruits at sulci and elsewhere on fruit surface; 3) measured fruit wall thickness and correlated it with bite-mark distribution in all four categories of fruit. RESULTS: 1) Bite marks were distributed at random only on surfaces of soft fruits. For other fruits types, bite locations were concentrated at the thinnest areas of husk, either over the entire surface (non-sulcate fruits), or at sulci (sulcate fruits). 2) For hard-husked fruits, areas where uacaris concentrated their bites were significantly easier to penetrate than those where they did not. CONCLUSIONS: This hard-fruit feeding specialist primate is not biting at random on the surface of diet fruits. To access seeds they are focusing on those areas requiring less force to penetrate. This may be to save energy, to minimize the risk of breaking teeth used in food processing, or a combination of both. The study shows, for the first time, the subtlety by which these powerfully-jawed animals process their diet items.
Assuntos
Força de Mordida , Dieta , Comportamento Alimentar/fisiologia , Frutas/fisiologia , Modelos Biológicos , Pitheciidae/fisiologia , Animais , Brasil , FemininoRESUMO
Pitheciids are known for their frugivorous diets, but there has been no broad-scale comparison of fruit genera used by these primates that range across five geographic regions in South America. We compiled 31 fruit lists from data collected from 18 species (three Cacajao, six Callicebus, five Chiropotes, and four Pithecia) at 26 study sites in six countries. Together, these lists contained 455 plant genera from 96 families. We predicted that 1) closely related Chiropotes and Cacajao would demonstrate the greatest similarity in fruit lists; 2) pitheciids living in closer geographic proximity would have greater similarities in fruit lists; and 3) fruit genus richness would be lower in lists from forest fragments than continuous forests. Fruit genus richness was greatest for the composite Chiropotes list, even though Pithecia had the greatest overall sampling effort. We also found that the Callicebus composite fruit list had lower similarity scores in comparison with the composite food lists of the other three genera (both within and between geographic areas). Chiropotes and Pithecia showed strongest similarities in fruit lists, followed by sister taxa Chiropotes and Cacajao. Overall, pitheciids in closer proximity had more similarities in their fruit list, and this pattern was evident in the fruit lists for both Callicebus and Chiropotes. There was no difference in the number of fruit genera used by pitheciids in habitat fragments and continuous forest. Our findings demonstrate that pitheciids use a variety of fruit genera, but phylogenetic and geographic patterns in fruit use are not consistent across all pitheciid genera. This study represents the most extensive examination of pitheciid fruit consumption to date, but future research is needed to investigate the extent to which the trends in fruit genus richness noted here are attributable to habitat differences among study sites, differences in feeding ecology, or a combination of both.
Assuntos
Dieta/veterinária , Frutas/classificação , Herbivoria , Pitheciidae/fisiologia , Plantas/classificação , Animais , Ecossistema , Florestas , Geografia , FilogeografiaRESUMO
Despite advances in the study of capuchin monkeys (Cebus and Sapajus), there is fairly limited information on their vocal communication systems. The present study focused on investigating the structure and use of vocalizations by wild blonde capuchin monkeys, Sapajus flavius. The study subjects produced 29 different call types, which we grouped into 10 categories according to their behavioral context. The number of call types per context varied from one to six. Some of the call types in the vocal repertoire were only produced by individuals of specific age classes. The "nhan" call, for instance, was only emitted by infants, whereas the "ghrr" call was specific to adults. Other call types had no age-specificity and were produced by animals of two or more age categories. Discriminant Function Analysis correctly classified 77.4% of calls to type (n = 14 types). The "huh" and "huh-1var" calls, which are food-associated calls, were most commonly used, together representing approximately 52% of recorded vocalizations. Information on the vocal repertoire of blonde capuchins increases our knowledge of this very little known and Critically Endangered species. Ultimately, it may be used as a tool to help survey these animals in the wild and to assess welfare in captivity.
Assuntos
Cebus/fisiologia , Vocalização Animal , Fatores Etários , Animais , Brasil , Espécies em Perigo de Extinção , Comportamento Alimentar , Feminino , MasculinoRESUMO
Tooth morphology is an important determinant of primate diet, setting potential limits on processable item size and material properties. Plunger-based commercial fruit firmness testers (penetrometers) have been used to estimate primate diet item hardness and, by proxy, bite force required for penetration. However, geometric forms and surface areas of penetrometer plungers and primate teeth differ considerably. Accurate bite force estimation is especially important with pitheciine primates as these penetrate fruit pericarps with their canines. To achieve more realistic bite force measures, we replaced a fruit penetrometer's standard plunger with a Cacajao calvus canine prosthesis. We compared indentation and penetration values for Hevea spruceana (Euphorbiaceae; hard-pericarp) and Mauritia flexuosa (Arecaceae; soft-pericarp) fruits (both natural Cacajao foods), and standard penetrometer head and canine prosthesis values for penetrating H. spruceana sulci. Compared to the canine prosthesis, a standard head overestimated the force needed to indent and penetrate H. spruceana fruit by more than twofold and, due to greater width, could not effectively penetrate a sulcus: sulcal penetrability data were easily retrieved with the canine prosthesis. We believe this new approach using dental prostheses has potential in the analysis of primate foraging mechanisms, especially for pitheciines for which canines are of paramount importance in accessing food.
Assuntos
Dente Canino/anatomia & histologia , Análise de Alimentos , Pitheciidae/anatomia & histologia , Animais , Arecaceae , Prótese Dentária , Dieta , Frutas , Testes de Dureza , HeveaRESUMO
Aim: This prospective study assessed the clinical and radiological outcomes of open tibia fractures treated with a dynamic external fixator. Materials and methods: Twenty-five patients underwent surgical debridement and stabilisation with a dynamic external fixator between November 2016 and April 2022. Regular follow-up evaluated bone healing progression. Results: Favourable outcomes were demonstrated in 20 patients. However, there were three cases of non-union, two of which subsequently deformed, and two cases of pin site-related infection. There were no fracture site infections. Conclusion: This study demonstrates the use of dynamic external fixation in the treatment of open tibia fractures. The low incidence of complications suggests its effectiveness and potential. How to cite this article: Bezerra BS, Araujo TA, Cardonia GG, et al. The Applicability of Dynamic External Fixator in a Prospective Evaluation of Open Tibial Fracture Treatment. Strategies Trauma Limb Reconstr 2024;19(1):36-39.
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The use of tools played a central role in human culture and evolution. Early studies with apes demonstrated the tool use; however, currently the works have focused on Platyrrhine, particularly capuchin monkeys. Blonde capuchin monkeys, Sapajus flavius, have been observed using sticks to fish for termites in the Atlantic Forest, where this species has been extensively studied. In this study, we presented the first evidence of stone tool use by the blonde capuchin monkeys, as well as the dimensions and weight of these tools. We gathered data from three areas of Caatinga dry forest where we discovered this new tool use among the species. The mean weight of the hammers was 475.7 g (± 142 SD). The mean height of the anvils was 48.3 cm (± 18.7 SD), while the mean surface area of the anvils was 1.2 m2 (± 0.4 SD). We identified fruits and/or nuts from three plant species-Prunus dulces, Cnidoscolus quercifolius, and Syagrus coronate-near the anvils at the study sites. Additionally, we passively observed six instances of stone tool use by blonde capuchin monkeys. Their use of stones to crack encased foods mirrored behaviors previously reported in Sapajus libidinosus, a species well known for using stone tools to exploit hard nuts. Our findings place blonde capuchin monkeys among the list of primates that utilize stones as tools, highlighting the species' adaptability in exploiting resources within the Caatinga. Long-term studies are essentials to comprehend the use pattern of stone tools (across both general and seasonal perspectives) and the influence of variables, such as fruit hardness, distance to watercourses, and fruit availability on the use of this technology by this primate.
Assuntos
Sapajus , Comportamento de Utilização de Ferramentas , Animais , Comportamento Alimentar , Brasil , Feminino , Masculino , Frutas , Nozes , Cebinae/fisiologiaRESUMO
Burning mouth syndrome (BMS) is defined as a chronic pain condition, characterized symptomatically by a generalized or localized burning sensation in the oral cavity. Various drugs have been used in attempting to treat BMS, but there is insufficient evidence to show the effect of any effective treatment. The aim of this review was to assess the effectiveness of therapies for BMS. Randomized controlled trials (RCTs) enrolling patients with a diagnosis of BMS were identified by searching Pubmed and Scoppus databases. The methodological quality of included studies was assessed on the basis of the method of allocation concealment, blindness of the study, loss of participants, size sample, and outcome concealment. A total of 12 relevant articles were analyzed. Therapies that used capsaicin, alpha-lipoic acid (ALA), and clonazepam were those that showed more reduction in symptoms of BMS. However, many studies of therapeutic interventions in BMS lack consistency in their results, because they use in their methodology, sample and a relatively short time of therapy and often do not provide a follow-up of patients treated. Thus, future studies are required to establish the treatment for patients suffering from this chronic and painful syndrome.
Assuntos
Síndrome da Ardência Bucal/tratamento farmacológico , Odontologia Baseada em Evidências , Antioxidantes/uso terapêutico , Capsaicina/uso terapêutico , Clonazepam/uso terapêutico , Moduladores GABAérgicos/uso terapêutico , Humanos , Ensaios Clínicos Controlados Aleatórios como Assunto/normas , Fármacos do Sistema Sensorial/uso terapêutico , Ácido Tióctico/uso terapêuticoRESUMO
Besides its extreme climate conditions, the Caatinga (a type of tropical seasonal forest) hosts an impressive faunal and floristic biodiversity. In the last 50 years there has been a considerable increase in the number of studies in the area. Here we aimed to present a review of these studies, focusing on four main fields: vertebrate ecology, plant ecology, human ecology, and ethnobiology. Furthermore, we identify directions for future research. We hope that the present paper will help defining actions and strategies for the conservation of the biological diversity of the Caatinga.
Assuntos
Conservação dos Recursos Naturais , Ecologia , Estações do Ano , Animais , Biodiversidade , Brasil , Humanos , PlantasRESUMO
Objectives: This study aimed to investigate the anti-erosive/abrasive effect of resin infiltration of previous deproteinized dentin. Materials and Methods: Dentin slabs were randomly assigned to 3 groups (n = 15): Control (no deproteinization; no resin infiltrant applied), RI (no deproteinization; resin infiltrant applied), and DRI (deproteinization; resin infiltrant applied). After undergoing the assigned treatment, all slabs were subjected to an in vitro cycling model for 5 days. The specimens were immersed in citric acid (0.05 M, pH = 3.75; 60 seconds; 3 times/day) and brushed (150 strokes). Between the challenges, the specimens were exposed to a remineralizing solution (60 minutes). The morphological alterations were analyzed by mechanical profilometry (µm) and scanning electron microscopy (SEM). Data were submitted to one-way analysis of variance (ANOVA) and Tukey tests (p < 0.05). Results: Control and RI groups presented mineral wear and did not significantly differ from each other (p = 0.063). DRI maintained a protective layer preserving the dentin (p < 0.001). After erosive/abrasive cycles, it was observed that in group RI, only 25% of the slabs partially evidenced the presence of the infiltrating, while, in the DRI group, 80% of the slabs presented the treated surface entirely covered by a resin-component layer protecting the dentin surface as observed in SEM images. Conclusions: The removal of the organic content allows the resin infiltrant to efficiently protect the dentin surface against erosive/abrasive lesions.
RESUMO
Semple et al. (Semple et al. in press, Biol. Lett. (doi:10.1098/rsbl.2009.1062)) argued that the 'law of brevity' (an inverse relationship between word length and frequency of use) applies not only to human language but also to vocal signalling in non-human primates, because coding efficiency is paramount in both situations. We analysed the frequency of use of signals of different duration in the vocal repertoires of two Neotropical primate species studied in the wild-the common marmoset (Callithrix jacchus) and the golden-backed uakari (Cacajao melanocephalus). The key prediction of the law of brevity was not supported in either species: although the most frequently emitted calls were relatively brief, they were not the shortest signals in the repertoire. The costs and benefits associated with signals of different duration must be appreciated to understand properly their frequency of use. Although relatively brief vocal signals may be favoured by natural selection in order to minimize energetic costs, the very briefest signals may be ambiguous, contain reduced information or be difficult to detect or locate, and may therefore be selected against. Analogies between human language and vocal communication in animals can be misleading as a basis for understanding frequency of use, because coding efficiency is not the only factor of importance in animal communication, and the costs and benefits associated with different signal durations will vary in a species-specific manner.
Assuntos
Callithrix , Pitheciidae , Vocalização Animal , AnimaisRESUMO
We report the spontaneous modification and use of sticks to fish for termites, above the ground, in wild blonde capuchins (Cebus flavius). These critically endangered Neotropical primates inhabit remnants of the Atlantic Forest. They used two previously undescribed techniques to enhance their termite capture success: nest tapping and stick rotation. The current ecologically based explanation for tool use in wild capuchins (i.e. terrestrial habits and bipedalism) must be viewed cautiously. Instead, remarkable manual skills linked to a varied diet seem important in promoting tool use in different contexts. The repertoire of tool-using techniques employed by wild capuchins has been expanded, highlighting the behavioural versatility in this genus.