Time filter

Source Type

Barelli C.,Sezione di Biodiversita Tropicale | Barelli C.,Leibniz Institute for Primate Research | Matsudaira K.,University of Tokyo | Matsudaira K.,Chulalongkorn University | And 7 more authors.
American Journal of Primatology

Knowledge of the genetic mating system of animal species is essential for our understanding of the evolution of social systems and individual reproductive strategies. In recent years, genetic methods have uncovered an unexpected diversity of paternal genetic contributions across diverse animal social mating systems, but particularly in pair-living species. In most pair-living birds, for example, genetic and behavioral observations have confirmed a previously unknown significance of extra-pair copulations (EPCs) and extra-pair paternity. Among mammals, white-handed gibbons (Hylobates lar) are also known to live in pairs and are traditionally believed to be single-male single-female breeders. However, at Khao Yai National Park, Thailand, behavioral observations have confirmed the occurrence of both EPCs and functional multi-male grouping, but knowledge about the genetic mating system is still unavailable. In this study, we genotyped 89 white-handed gibbons of the Khao Yai population based on fecal samplings and were able to determine paternity for 41 offspring through short tandem repeat analysis. We found that females' stable social partners sired the majority (90.5%) of offspring (N=38), while only a few (7.1%) offspring (n=2 confirmed cases; n=1 inferred case) were conceived with extra-pair partners. The paternity of one offspring remained inconclusive (2.4%), because the offspring's genotype did not mismatch with the genotypes of two potential sires. Like other predominantly pair-living species, gibbons appear to follow a mixed-reproductive strategy. The genetic mating system of wild white-handed gibbons is best described as flexible, primarily monogamous and opportunistically promiscuous. © 2013 Wiley Periodicals, Inc. Source

Araldi A.,Reproductive Biology Unit | Barelli C.,Reproductive Biology Unit | Barelli C.,Research and Innovation Center Fondazione Edmund Machinery | Hodges K.,Reproductive Biology Unit | And 2 more authors.
International Journal of Primatology

Estimates of population density and abundance are essential for the assessment of nonhuman primate conservation status, especially in view of increasing threats. We undertook the most extensive systematic primate survey yet of the Udzungwa Mountains of Tanzania, an outstanding region for primate endemism and conservation in Africa. We used distance sampling to survey three arboreal monkey species, including the endangered and endemic Udzungwa red colobus (Procolobus gordonorum). Overall, we encountered 306 primate clusters over 287 km walked along 162 line transects. We found the lowest cluster densities for both red colobus and Angolan colobus (Colobus angolensis; 0.8 clusters/km2) in the least protected forest (Uzungwa Scarp Forest Reserve, US), while we found the highest densities (3.2 and 2.6 clusters/km2 for red colobus; 3.2 and 2.7 clusters/km2for Angolan colobus) in two large and protected forests in the national park. Unexpectedly, Magombera, a small forest surrounded by plantations, had the highest densities of red colobus (5.0 clusters/km2), most likely a saturation effect due to the rapid shrinking of the forest. In contrast, Sykes’ monkey (Cercopithecus mitis monoides/moloneyi) had more similar densities across forests (3.1–6.6 clusters/km2), including US, suggesting greater resilience to disturbance in this species. For the endemic red colobus monkey, we estimated an abundance of 45–50,000 individuals across all forests, representing ca. 80% of the global population. Though this is a relatively high abundance, the increasing threats in some of the Udzungwa forests are of continued concern for the long-term survival of red colobus and other primates in the area. © 2014, Springer Science+Business Media New York. Source

Kaufman J.A.,Midwestern University | Turner G.H.,Barrow Neurological Institute | Holroyd P.A.,University of California at Berkeley | Rovero F.,Sezione di Biodiversita Tropicale | And 2 more authors.

The Gray-faced Sengi (Rhynchocyon udzungwensis) is a newly-discovered species of sengi (elephant-shrew) and is the largest known extant representative of the order Macroscelidea. The discovery of R. udzungwensis provides an opportunity to investigate the scaling relationship between brain size and body size within Macroscelidea, and to compare this allometry among insectivorous species of Afrotheria and other eutherian insectivores. We performed a spin-echo magnetic resonance imaging (MRI) scan on a preserved adult specimen of R. udzungwensis using a 7-Tesla high-field MR imaging system. The brain was manually segmented and its volume was compiled into a dataset containing previously-published allometric data on 56 other species of insectivore-grade mammals including representatives of Afrotheria, Soricomorpha and Erinaceomorpha. Results of log-linear regression indicate that R. udzungwensis exhibits a brain size that is consistent with the allometric trend described by other members of its order. Inter-specific comparisons indicate that macroscelideans as a group have relatively large brains when compared with similarly-sized terrestrial mammals that also share a similar diet. This high degree of encephalization within sengis remains robust whether sengis are compared with closely-related insectivorous afrotheres, or with more-distantly-related insectivorous laurasiatheres. © 2013 Kaufman et al. Source

Anile S.,University of Catania | Ragni B.,University of Perugia | Randi E.,European Commission - Joint Research Center Ispra | Mattucci F.,European Commission - Joint Research Center Ispra | Rovero F.,Sezione di Biodiversita Tropicale
Journal of Zoology

The European wildcat is an elusive felid that is declining across its range. Sicily hosts a distinctive insular wildcat population, the conservation of which requires much better ecological knowledge than is currently available, particularly population density. We simultaneously used two noninvasive methods (camera-trapping and scat-collection) to estimate the population density of wildcats on the Etna volcano. We conducted genetic analyses to identify individuals and to detect potential hybridization with the domestic cat. We analyzed individual capture-histories from camera-trapping and scat-collection using the spatially explicit capture-recapture (SECR) model. Furthermore, we applied the random encounter model (REM), which does not require individual identification, to the camera-trapping data. We identified 14 wildcats from 70 photographic detections (6.48 detections/100 trap-days) obtained from 1080 camera-trapping days over 4 months, and we estimated to have identified all the individuals living in the study area (10.9km-2). On the contrary, we identified 10 wildcats from 14 out of 39 scats collected from 391km of transects walked. The estimated densities (individualskm-2±se) were 0.32±0.1 (SECR camera-trapping), 1.36±0.73 (SECR scat-collection) and 0.39±0.03 (REM). The population density estimates obtained from SECR camera-trapping and REM overlapped, although we recommend care when applying the latter. The SECR scat-collection gave the highest population density (and less precise) estimates because of the low number of capture and recaptures; however, the population size estimated with this method matched the number of individuals photographed. The population density of the wildcat in Etna falls in the medium-high range of those reported in literature, highlighting the role of this ecosystem for the long-term conservation of the wildcat in Sicily. Camera-trapping is confirmed as a useful tool to assess the wildcat population density and, in this case, was complemented by the genetic analysis that confirmed individual identity. © 2014 The Zoological Society of London. Source

Klailova M.,University of Lisbon | Klailova M.,University of Stirling | Casanova C.,University of Lisbon | Henschel P.,Panthera | And 3 more authors.
Folia Primatologica

The slow life histories of great apes (hereafter 'apes') combined with a growing inventory of predation incidents suggest that apes may be strongly affected by direct predation, as well as by predation risk. Predation risk may shape and increase behavioural flexibility by forcing individuals to adapt their behaviour to predator patterns. Forest leopards are an apex predator of primates in African rain forests and may represent a significant risk to ape populations. More field data are needed to further elucidate the behavioural modifications of apes in response to predation. We present research methods that combine the use of remote camera traps, capture-mark-recapture statistics and occupancy modelling to study predator-African ape relationships and potential antipredator behaviour through spatial variation in species co-occurrence patterns. © 2013 S. Karger AG, Basel. Source

Discover hidden collaborations