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The social group hierarchy of three captive C. petaurista specimens was monitored and determined by observing agnostic fights, aggression, and allogrooming incidents. This social group was monitored from May to August in 2017 for 60.5 observation hours total as a continuation of a previous study conducted in spring of 2017. The study took place at the Central Florida Zoo and Botanical Gardens. All observations were recorded on template sheets with the location of each individual noted on a 6x6 grid representing the enclosure. A new sheet was used for each 15-minute increment during observation periods. It was concluded that agnostic fight outcomes were influenced by social hierarchy, with more dominant individuals consistently winning encounters with less dominant individuals. It was also notable how the dominant male would step in to help settle agnostic fights, enforcing the hierarchy among less dominant individuals. Allogrooming also was influenced by hierarchy. Grooming incidents among the observed specimens followed the Seyfarth model, meaning that grooming tended to take place among individuals of adjacent rank. [ABSTRACT FROM AUTHOR]

In this study we tested an adult female Martin's spot-nosed monkey in several configurations of the string-pulling paradigm, including six different discrimination problems of patterned strings. Our subject solved almost all of the problems presented. Although she seemed to have a spatial preference in the most complex tasks, she maintained a high success rate in almost all of them. She also showed goal-directed behaviour that was not strictly based on visual feedback. Although more research is needed to understand better the subject's performance, we conclude that she showed clear signs of understanding physical continuity, and some degree of understanding of connectedness and causal relationships. [ABSTRACT FROM AUTHOR]

The central position and universality of music in human societies raises the question of its phylogenetic origin. One of the most important properties of music involves harmonic musical intervals, in response to which humans show a spontaneous preference for consonant over dissonant sounds starting from early human infancy. Comparative studies conducted with organisms at different levels of the primate lineage are needed to understand the evolutionary scenario under which this phenomenon emerged. Although previous research found no preference for consonance in a New World monkey species, the question remained opened for Old World monkeys. We used an experimental paradigm based on a sensory reinforcement procedure to test auditory preferences for consonant sounds in Campbell's monkeys (Cercopithecus campbelli campbelli), an Old World monkey species. Although a systematic preference for soft (70 dB) over loud (90 dB) control white noise was found, Campbell's monkeys showed no preference for either consonant or dissonant sounds. The preference for soft white noise validates our noninvasive experimental paradigm, which can be easily reused in any captive facility to test for auditory preferences. This would suggest that human preference for consonant sounds is not systematically shared with New and Old World monkeys. The sensitivity for harmonic musical intervals emerged probably very late in the primate lineage. [ABSTRACT FROM AUTHOR]

Field studies on male forest guenon alarm-calling behaviour have revealed a number of intricacies about how these primates use vocalizations to protect themselves from predation. In these species, the vocal behaviour of adult females is often different from that of the males, but little systematic work has been done. Here, we describe the alarm call system of female Campbell''s monkeys, Cercopithecus campbelli, in their natural forest habitat in western Ivory Coast. We found that in response to disturbing events, females produced three basic alarm call types, ‘wak-oos’, ‘hoks’ and acoustically variable ‘trill’ calls, consisting of repeated and rapidly ascending (RRA) pulses, which varied systematically in the temporal and frequency domains. Using observational and experimental data we were able to demonstrate that the RRA calls consisted of four acoustic variants, which could be associated with specific contexts, allowing listeners to draw inferences about the type of disturbance experienced by the caller. We also compared the alarm call behaviour of free-ranging individuals with published results from captivity. As predicted, captive individuals failed to produce predator-specific alarm calls, but they also produced an RRA variant in response to humans that was absent in the wild. We discuss the relevance of these findings in terms of their broader potential impact on evolutionary theories of primate communication. [Copyright &y& Elsevier]

I studied the positional behavior and habitat use of Cercopithecus petaurista, the lesser spot-nosed monkey, in the Ivory Coast's Taï Forest for 15 months. I compare these data with similar information collected on sympatric groups of Cercopithecus diana and C. campbelli in order to examine further the relationships between locomotion, posture, support use, stratal use, body size, diet, activity patterns and foraging behavior. Spot-nosed monkeys are predominantly quadrupedal primates that frequent the top layer of the understory during all maintenance activities. Locomotion is characteristically slow and cautious; travel takes place on branches and boughs while foraging occurs on twigs and branches. Postural behavior of Cercopithecus petaurista reflects their reliance on more ubiquitously distributed, less mobile food items. The relationship between body size, climbing, leaping and support use among Taï guenons is weak; interspecific differences are more likely functions of strata use and overall behavioral characteristics, e.g. crypticity. I also compare the locomotion and support use of Cercopithecus petaurista with that of C. ascanius from Uganda's Kibale Forest (Gebo and Chapman, 1995a) in order to assess the behavioral similarity of members of the same superspecies. Although overall support use is quite similar, the monkeys differ significantly in frequencies of quadrupedism, leaping and climbing. I present possible reasons for and implications of these differences. [ABSTRACT FROM AUTHOR]

Tests hypotheses on animal vocalizations using field playback experiments on diana monkeys or Cercopithecus diana diana. Response to calls of leopards and eagles and the males' alarm calls to these predators; Subjects' transfer of habituation across acousting but not semantic features; Response to the calls' underlying meanings; Issue of perceptual or conceptual semanticity.

Presents information on a report of the integration of single male crowned guenons (Cercopithecus pogonias) into troops of black colobus (Colobus satanas). Observation of one male Cerocopithecus pogonias in three troops of Colobus satanas; Amount of days the male was observed; Occurrence of interspecific grooming; Detailed information on the integration; Suggestions of the main benefits.

Sympatric guenons in East Africa associate with one another in mixed-species groups to an intermediate degree. This makes it possible to compare a given group's ecology and behavior when it is part of an association to when it is unaccompanied, and to correlate association tendency with various ecological parameters. Two studies, incorporating these approaches have been made to sympatric Cercopithecus ascanius and C. mitis monkeys in the Kakamega Forest, Kenya, and the Kibale Forest, Uganda. The pattern of and reasons for association in each site are reviewed. Compared to Kakamega, association between C. ascanius and C. mitis in Kibale occurs less often, and the species appear to benefit relative to one another in different ways. These results suggest that the particular ecological setting greatly influences the nature of the interaction between species, through its effect on population structure, dietary overlap, food distribution, and community composition. The major ecological differences between the two study areas probably reflect post-Pleistocene history and possibly climate, but they have important consequences for the present-day population structure and feeding ecology of each species, and hence affect relations between them as well. [ABSTRACT FROM AUTHOR]

Rodents commonly approach sources of threat in a characteristic posture of stretched approach. There is considerable support for the view that the function of stretched-approach sequences is the acquisition of information about potential sources of danger. To determine whether monkeys, like rodents, engage in defensive information gathering, we recorded the behavior of three Old World monkeys ( Cercopithecus species) after each had been exposed to threat in a seminatural environment. Each monkey displayed an intense startle and flight reaction when a jack-in-the-box that it was inspecting was triggered. Nevertheless, within seconds ( M = 8 s), each monkey returned to the jack-in-the-box and spent much of the 20-min test session inspecting it ( M = 905 s) while largely ignoring the stuffed-bear control object ( M = 203 s). These results, in combination with previous studies of stretched-approach behavior in rodents, suggest that information gathering is an important defensive strategy in a variety of mammalian species. In the past two decades, theories of animal behavior have started to portray animals as users of information rather than as S-R automatons. Recent ethoexperimental studies of animal defense indicate that animals are more than passive receivers of information. Animals exposed to a threatening object purposefully approach the object to collect information about it. [ABSTRACT FROM AUTHOR]