1,721,008 research outputs found
First report of leaf swallowing and parasite expulsion in an Asian small ape
No full textLeaf swallowing behaviour, known as a form of self-medication for the control of nematode
and tapeworm infection, occurs widely in all the African great apes. It is also reported to occur in
a similar context across a wide array of other animal taxa including, domestic dogs, wolves, brown
bears and civets. Despite long-term research on Asian great and small apes, this is the first report
of leaf swallowing in an Asian species, the white-handed gibbon ( Hylobates lar ) in Khao Yai National
Park, central Thailand. We present the first evidence of leaf swallowing ( Gironniera nervosa
Planch CANNABACEA) behaviour (n = 5 cases) and parasite (Streptopharagus pigmentatus) expulsion (n = 4 cases), recorded during 4,300 h of direct animal observations during 2 distinct
research projects. We recovered 4 – 18 rough, hairy and hispid surfaced leaves from each
sample, undigested and folded, from the freshly evacuated faeces of 5 different individuals (2
males, 3 females, 5 ∼ 34+ years old) living in 3 different social groups. Based on close inspection
of the leaves, as observed in chimpanzees, it was clear that leaves were taken into the mouth, one
at a time, folded and detached from the stem with the teeth before swallowing them whole. All
instances occurred during the rainy season, the time when nematode worms were also found in
the faeces. These striking similarities in the details of leaf swallowing between white-handed gibbons
and African great apes, and other animal species, suggest a similar anti-parasitic functio
Conserve the germs: the gut microbiota and adaptive potential
Full text linkAlthough the diversity of microbial communities (microbiota) inhabiting body niches are of proven importance to health
in both humans and non-human animals, the functional importance of these collective genomes (microbiome) to the adaptive potential of their hosts has only recently been considered within a conservation framework. If loss of gut biodiversity
threatens the health (and therefore the fitness of individuals), and this loss can be correlated with the adaptive potential of a
species in changing environments, measuring functional composition of the microbiota from non-invasive samples, such as
faeces and skin swabs, could provide a useful and practical tool for determining conservation priorities. This article reviews
the evidence for adaptive potential of microbiota in wild species, and proposes future directions. While there is ample
indication of inter- and intra-specific variation in microbiota diversity, there is little evidence that diversity per se confers
fitness. However, there are convincing examples showing that microbiota flexibility, composition and function may well be
sources of adaptive potential, although case studies are relatively few, and the analytical approaches needed to demonstrate
the mechanisms underlying host–microbiota interactions have only recently been developed
Habitat complexity and its use correlate with soil-transmitted helminthiasis in two social groups of Macaca maura (H.R. Schinz, 1825), endangered primates endemic to Sulawesi island, Indonesia
Full text linkSulawesi endemic Macaca maura is included in the IUCN Red List as Endangered due to
anthropogenic disturbance and fragmentation of its habitat. Residual populations have a scattered
distribution in the karst forests of south Sulawesi. Here the dissolution of limestone layers
has created a multi-level landscape hardly accessible for ground predators and humans. In this
study, we aimed to obtain better knowledge on the ecological flexibility of M. maura in the use
of such a complex habitat, and its consequences on health status. Since all data published on M.
maura were obtained from a single group (group B), an additional group (G) was habituated to
human presence. We analysed 50 vegetation plots (10 × 20 metres) to discriminate structural
features in terms of feeding options (e.g. key food species diversity, density and DBH) and anthropogenic
disturbance (e.g. human trails and solid litter). We then correlated these data with
habitat use and helminth infection. We collected 74 faecal samples from 18 different adult individuals
belonging to both groups. Vegetation analysis suggested that there were 2 suitable habitats:
a Ground Forest (e.g. higher abundance of key food species) and a Karst Tower Forest (e.g.
lower presence of human trails and solid litter). Gastrointestinal investigation revealed a positive
correlation between the prevalence of Trichuris sp. and time devoted to ground food-related activities
in all individuals (Spearman correlation, rs = 0.665, p = 0.003). Moreover, behavioural
data confirmed that group B, the larger study group of the area, spent most of its activity time in
the Ground Forest (N group B = 33 ± 1; N group G = 18 ± 1; χ 2
= 134.30, d.f. = 1, p < 0.001). Since resource
availability and predation risk can influence foraging decisions and, ultimately, space use,
the “group size effect” might explain the significantly higher proportion of time spent by group
B in the Ground Forest. Consequently, due to the Trichuris faecal-oral contamination life-cycle,
the chance of infecting individuals based on their feeding habits might be described according to
the “soil-transmitted helminthiasis hypothesis
Going Beyond Counting First Authors in Author Co-citation Analysis
Full text linkThe 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
Variations on the Author
Full text link“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
Full text linkWe 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
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