1,720,970 research outputs found
Sex Differences in the Use of Whinny Vocalizations in Spider Monkeys (Ateles geoffroyi).
No full textSpider monkey social groups are characterized by male philopatry and high fission-fusion dynamics. Individuals form subgroups that temporally vary in size, composition, and spatial cohesion. Both sexes produce whinny vocalizations, which may allow close associates to maintain contact in dispersed subgroups. Females however do not form close bonds, therefore the use of their call remains unresolved. We investigate sex differences in the use of whinny vocalizations by the Yucatan spider monkey (Ateles geoffroyi yucatanensis) at Runaway Creek Nature Reserve, central Belize. Females called at higher rates than males in most behavioral contexts, particularly while foraging. The likelihood of female calling increased during subgroup fissions and fusions, and was positively correlated with the number of animals joining or leaving a subgroup. Neither behavioral context, nor changes in subgroup composition affected the likelihood of calling by males. These different patterns indicate that the call may function differently for each sex
Lost in Transmission: Contextual Variation in Chimpanzee Pant Hoots and its Implications for Referential Communication presented at the Animal Behaviour Society 45th Annual Meeting in Snowbird Resort, UT, August 16-20, 2008
No full textI attended the 45th annual meeting of the Animal Behavior Society in Snowbird, Utah, from 16-20 August 2008. The meetings included 4 plenary speakers, a symposium on evolutionary polyphenisms, contributed talks and posters. As is typical of ABS meetings, presentations covered a broad range of research topics on a variety of taxa, but all presenters converged on themes that are topical and cutting edge in the field of animal behaviour. As a primatologist, I have found attending meetings with a broad taxonomic focus invaluable for gaining insights into comparative approaches to studying different domains of behaviour in primates.
My contributions consisted of a paper on my work in chimpanzee communication, of which I was first author and presenter, as well as a paper on structural-function relationships in baboon vocalizations, on which I was second author (the first author was presenter). Both papers were well received and they generated positive commentary from attendees, particularly those involved in the field of animal communication. I was encouraged to continue to apply my theoretical approach to the study of animal vocalizations.
At present, I am starting a new primate research program on New World monkeys in Belize, CA. In future meetings I hope to present data generated by this endeavour, as soon as they become available. International meetings such as those hosted by ABS offer excellent opportunities for Athabasca University to showcase the work of its faculty and to build the university’s reputation as a leader in innovative research.There have been several previous studies of the loud, long-distance calls of chimpanzees, termed ‘pant hoots’. Some have explored the possibility that there are acoustically distinct subtypes of pant hoots that communicate to distant listeners different information about the caller’s behaviour, or ecological and social circumstances. However, research aimed at assessing the degree to which pant hoots constitute ‘referential’ animal signals have thus far been either inconclusive or conflicting. To help resolve these issues, we undertook research on pant hoots produced by wild chimpanzees (Pan troglodytes schwienfurthii) living in the Budongo Forest, Uganda. In this paper, we report the results of acoustic analysis of 201 pant hoot series produced by seven adult males. Our results show that individual variation exceeds those differences observed between production contexts. In addition, what contextual variation we did observe occurred in acoustic features that are expected to vary with arousal and/or as by-products of physical activities associated with call production. We propose that pant hoots function primarily to transmit information about caller identity to dispersed group members, and that receivers might infer the situational context of the caller via associated auditory cues, such as caller location, direction of travel and social circumstance, that are independent of call structure.Academic & Professional Development Fund (A&PDF
Seasonal Variation in Sexual Segregation in spider Monkeys (Ateles GeoffroyI Yucatanensis) at Runaway Creek Nature Preserve Belize
No full textI attended the annual meeting of the American Society of Primatologists in Austen, Texas during September 15-20. This meeting brings together society members, many of whom (despite the regional focus implicated in the society’s name) are internationally renowned in the discipline. I presented a paper in a symposium entitled “Ecology of Behaviour” on research that I and my current PhD student are working on – the mechanisms for, and variation in sexual segregation in spider monkeys. The data are derived from our on-going primate research site in Belize.
The paper was well-received as this phenomenon has not been formally analyzed in this species. The originality of our approach involved the use of an index that has been applied to a similar phenomenon in ungulates, but never before in primates. We did receive feedback concerning other mechanisms to explore (as hypotheses to be tested) regarding the function of sexual segregation, and this is something Kayla Hartwell, my PhD student and co-author on the paper, will incorporate into her thesis project.Sexual segregation, the separation of males and females socially or by habitat, has been recognized as a dimension of the socio-ecology of many vertebrates, but has not been quantified or systematically examined in primates. We investigated temporal patterns of sexual segregation in a population of spider monkeys in Belize. Using data collected over a 23 month study, we applied the Sexual Segregation and Aggregation Statistic to test three hypotheses: i) the sexes segregate, ii) the sexes aggregate, or iii) the sexes associated at random. Our analysis revealed that spider monkeys live in primarily sex-segregated societies, but that patterns of segregation varied within and between years: males and females segregate most of the year, except when food availability is lowest. Males and females had significantly different activity budgets; males spent more time travelling, and less time resting and feeding, than females. However, same-sex groups were less synchronous in their behavioural activities than were mixed groups. Males had a higher proportion of ripe fruit in their diets than females did, who ate more leaves and unripe fruit. We propose that sexual segregation in spider monkeys is primarily a form of social segregation that results from males and females pursuing different strategies for optimizing sex-specific energy requirements and reproductive demands. We suggest that the fission-fusion social patterning typical of spider monkeys in which males and females often form same-sexed subgroups emerges from social segregation. Supported by NSERC and Athabasca University research fund
Going Beyond Counting First Authors in Author Co-citation Analysis
No full textThe present study examines one of the fundamental aspects of author co-citation analysis (ACA) - the way co-citation
counts are defined. Co-citation counting provides the data on which all subsequent statistical analyses and mappings
are based, and we compare ACA results based on two different types of co-citation counting - the traditional type that
only counts the first one among a cited work's authors on the one hand and a non-traditional type that takes into
account the first 5 authors of a cited work on the other hand. Results indicate that the picture produced through this non-traditional author co-citation counting contains more coherent author groups and is therefore considerably clearer. However, this picture represents fewer specialties in the research field being studied than that produced through the traditional first-author co-citation counting when the same number of top-ranked authors is selected and analyzed. Reasons for these effects are discussed
Demography, Diet and Range Size in a Population of Black-handed Spider Monkey's
No full textThe International Primatological Society (IPS) congress takes place every two years, and this year was in Kyoto, Japan. As the name suggests, this conference brings together primate researchers from around the globe and promotes the dissemination and discussion of current research via a combination of plenary speakers, symposia, and oral and poster sessions over a week-long period. Abstracts are reviewed and published in conference proceedings, and all presentations are meant to elicit discussion and commentary.
This year, I presented pilot data from a new study site I have initiated in Belize using RIG funding. I co-authored this presentation with a research colleague at the University of Calgary, who is also one of the PIs at our site. We currently co-supervise 2 graduate students working at the site, and both students presented posters at the IPS congress. I was a co-author one both posters. One of the posters (Kayla Hartwell’s poster on sex segregation) won second place in the student competition. In addition, as these students were masters students, this was their first international conference, and I played an important role in facilitating their connecting to other researchers in the discipline.
In general, the conference was a success for all of us (me and my graduate students). We have been encouraged to continue our work on sex segregation, and indeed this has become the focus of Kayla’s upcoming PhD research.#1
Studies of wild Ateles geoffroyi yucatensis have occurred, or are ongoing in Mexico, Guatemala and Costa Rica, but no sites have been established in Belize. Across study sites, group composition, average sub-group size, diet and ranging patterns vary as a function of ecological and demographic variables particular to respective locations. Here we describe the age and sex compositions, average sub-group sizes, range sizes, activity budgets and diets of two recently habituated groups of spider monkeys at Runaway Creek Nature Preserve in Belize. Habituation and data collection began in June 2007 using a combination of all occurrences recording and group scans. Two separate and adjacent monkey groups were identified – Groups 1 and 2 – numbering 33 and 31 individuals respectively. Range sizes for both groups were determined using a minimum convex polygon of GPS location points. Group 1 ranged over an area of 114.43 ha (N=678) and Group 2 over 193.67 ha (N=181). Average sub-group size for all individuals of all age/sex classes in Group 1 group was 5.16 individuals, with a mode of 2 (N=415). In Group 2, average sub-group size was 4.48 individuals, with a mode of 3 (N=106). Between June 2007 and July 2009 the spider monkeys from both groups were observed feeding from 70 different plant species. These and future data emanating from this new study site represent an important addition to a small but growing number of studies that will further our understanding of within-species variability in response to differing socio-ecological variables across the range of Ateles.
#2
Infant handling by adults other than the mother occurs to varying degrees across primate species and social organizations. Among males infant handling may reflect kinship-based affiliation, bond formation or a reproductive strategy that facilitates access to the mother. Spider monkeys (Ateles spp.) exhibit male philopatry and therefore males may preferentially handle male infants as they could be potential future allies. To investigate this hypothesis, all occurrence data were collected from January 2007 to December 2009 on a community of 35 wild spider monkeys at Runaway Creek Nature Reserve, Belize. During 555 hours of observation, 59 infant handling bouts and 12 infant handling attempts were recorded. All of the 11 infants were handled by individuals other than the mother during the study period. Handling of infants by adult, sub-adult and large juvenile males was the most common [N=48, or 81% of all bouts]. Infant handling by adult, sub-adult and large juvenile females was less common [N=11, or 19% of all bouts], but a higher proportion of handling bouts by females resulted in prolonged infant carries [0.36 for females; 0.10 for males]. Individual adult and sub-adult males varied with respect to their probability of handling an infant [Pearson X2=14.25, df=4, p<0.05]. The sex of the infant did not affect how often it was handled by males [Pearson X2=3.84, df=1, p=0.36]. As all infants born in a male philopatric group are presumed to share some degree of paternal kinship, we suggest that male infant handling in A. geoffroyi reflects kinship-based affiliation or tolerance.
#3
Sexual segregation, the social and/or spatial separation of males and females, has been characterized in many animals; however, no systematic analysis has yet been undertaken to measure sex segregation in primates. Using data from a 7-month study on a community of spider monkeys in Belize, we used the Sexual Segregation Aggregation Statistic (SSAS) to determine if the sexes segregate or aggregate. We then determined if the patterns are driven by social, habitat, or reproductive differences between males and females. SSAS values range from 0 (complete aggregation) to 1 (complete segregation). The overall SSAS value suggests that male and female spider monkeys are slightly more segregated (SSAS=0.56) than aggregated. However segregation varies monthly; there is more segregation during the dry season months (January-April: 0.66-0.85) and more aggregation during the wet season months (May-July: 0.27-0.45). Several hypotheses have been proposed to explain the causes of segregation, such as the forage selection and predation risk hypotheses for habitat segregation and the social preferences and activity budget hypotheses for social segregation. Despite low levels of dimorphism in spider monkeys, high fission-fusion dynamics may lead to different activity budgets for males and females, which in turn favors segregation to meet different reproductive agendas. Males and females differ significantly in time spent traveling, feeding and socializing. Spider monkeys also prefer to associate with same-sex partners. Since males and females do not differ in habitat use, segregation in spider monkeys is best explained by sex differences in activity budgets and social preferences
Variations on the Author
No full text“Variations on the Author” discusses two of Eduardo Coutinho’s recent films (Um Dia na Vida, from 2010, and Últimas Conversas, posthumously released in 2015) and their contribution to the general question of documentary authorship. The director’s filmography is characterized by a consistent yet self-effacing form of authorial self-inscription: Coutinho often features as an interviewer that rather than express opinions propels discourses; an interviewer that is good at listening. This mode of self-inscription characterizes him as an author who is not expressive but who is nonetheless markedly present on the screen. In Um Dia na Vida, however, Coutinho is completely absent form the image, while Últimas Conversas, on the contrary, includes a confessional prologue that moves the director from the margins to the center of his films. This article examines the ways in which these works stand out in the filmography of a director who offers new insights into the notion of cinematic authorship
Appropriate Similarity Measures for Author Cocitation Analysis
No full textWe provide a number of new insights into the methodological discussion about author cocitation analysis. We first argue that the use of the Pearson correlation for measuring the similarity between authors’ cocitation profiles is not very satisfactory. We then discuss what kind of similarity measures may be used as an alternative to the Pearson correlation. We consider three similarity measures in particular. One is the well-known cosine. The other two similarity measures have not been used before in the bibliometric literature. Finally, we show by means of an example that our findings have a high practical relevance.information science;Pearson correlation;cosine;similarity measure;author cocitation analysis
Dispelling the Myths Behind First-author Citation Counts
No full textWe conducted a full-scale evaluative citation analysis study of scholars in the XML research field to explore just how different from each other author rankings resulting from different citation counting methods actually are, and to demonstrate the capability of emerging data and tools on the Web in supporting more realistic citation counting methods. Our results contest some common arguments for the continued
use of first-author citation counts in the evaluation of scholars, such as high correlations between author rankings by first-author citation counts and other citation
counting methods, and high costs of using more realistic citation counting methods that are not well-supported by the ISI databases. It is argued that increasingly available digital full text research papers make it possible for citation analysis studies to go beyond what the ISI databases have directly supported and to employ more
sophisticated methods
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