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Wilmet Leslie - One of the best experts on this subject based on the ideXlab platform.
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Data on the diet of Lepilemur mittermeieri, a sportive lemur endemic to the northwest of Madagascar
2020Co-Authors: Wilmet Leslie, Devillers Pierre, Vermeulen Cédric, Beudels-jamar, Roseline C.Abstract:Mittermeier’s sportive lemur (Lepilemur mittermeieri) is an endangered primate endemic to the Ampasindava peninsula, in north-west Madagascar. Lepilemur are known to be folivores with a low metabolic rate, but no specific investigation of the diet of Mittermeier’s sportive lemur has been reported. In 2015 and 2016, we conducted a field study of the species in two areas of the Ampasindava peninsula, involving direct observation of individuals equipped with radio-collars. We verified that Mittermeier’s sportive lemur is a solitary forager. We identified a total of 77 tree species consumed and a large variation in the spectrum of species used within the two studied sites. Most of the plant material consumed was made of leaves, with few fruits.Peer reviewe
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Data on the diet of Lepilemur mittermeieri, a sportive lemur endemic to the northwest of Madagascar
Madagascar Section of the IUCN SSC Primate Specialist Group, 2020Co-Authors: Wilmet Leslie, Devillers Pierre, Vermeulen Cédric, Beudels-jamar, Roseline C.Abstract:peer reviewedaudience: researcher, professional, studentMittermeier’s sportive lemur (Lepilemur mittermeieri) is an endangered primate endemic to the Ampasindava peninsula, in north-west Madagascar. Lepilemur are known to be folivores with a low metabolic rate, but no specific investigation of the diet of Mittermeier’s sportive lemur has been reported. In 2015 and 2016, we conducted a field study of the species in two areas of the Ampasindava peninsula, involving direct observation of individuals equipped with radio-collars. We verified that Mittermeier’s sportive lemur is a solitary forager. We identified a total of 77 tree species consumed and a large variation in the spectrum of species used within the two studied sites. Most of the plant material consumed was made of leaves, with few fruits
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Updated population density estimation and distribution range of the Critically Endangered Sahamalaza sportive lemur, Lepilemur sahamalaza
2020Co-Authors: Mandl Isabella, Schwitzer Christoph, Rabemanajara Naina, Wilmet LeslieAbstract:Accurate population density estimates are important for effective conservation measures of endangered species. For the Critically Endangered Sahalamaza sportive lemur (Lepilemur sahamalaza), no recent or robust population estimates are available, complicating conservation management of this species. This study examined the species distribution range as well as assessing population density in the range of occurrence with standardized methodology (transect walks and home range calculations) between 2013 and 2016. The results suggest that Sahamalaza sportive lemurs are confined to the Sahamalaza Peninsula. Population density ranges between 1.49 to 1.87 individuals/ha depending on the methodology used to estimate density. Population size estimates consequently vary between 3800 and 4700 remaining individuals of this species, subject to a re-evaluation of the remaining habitat.Peer reviewe
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Updated population density estimation and distribution range of the Critically Endangered Sahamalaza sportive lemur, Lepilemur sahamalaza
Madagascar Section of the IUCN SSC Primate Specialist Group, 2020Co-Authors: Mandl Isabella, Schwitzer Christoph, Rabemanajara Naina, Wilmet LeslieAbstract:peer reviewedaudience: researcher, professional, studentAccurate population density estimates are important for effective conservation measures of endangered species. For the Critically Endangered Sahalamaza sportive lemur (Lepilemur sahamalaza), no recent or robust population estimates are available, complicating conservation management of this species. This study examined the species distribution range as well as assessing population density in the range of occurrence with standardized methodology (transect walks and home range calculations) between 2013 and 2016. The results suggest that Sahamalaza sportive lemurs are confined to the Sahamalaza Peninsula. Population density ranges between 1.49 to 1.87 individuals/ha depending on the methodology used to estimate density. Population size estimates consequently vary between 3800 and 4700 remaining individuals of this species, subject to a re-evaluation of the remaining habitat
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Use of space and home range characteristics of Lepilemur mittermeieri, an endangered sportive lemur endemic to the Ampasindava peninsula, north‐west Madagascar
2019Co-Authors: Wilmet Leslie, Schwitzer Christoph, Devillers Pierre, Beudels-jamar, Roseline C., Rakotondrainibe Hajanirina, Vermeulen CédricAbstract:Lepilemur mittermeieri, a little‐studied sportive lemur of north‐west Madagascar, endemic to the Ampasindava Peninsula, faces habitat loss through forest degradation and rapid fragmentation. Understanding its habitat requirement is the first step toward preservation of this threatened forest‐dependent species. In this study, we gathered data on the use of space and home range characteristics of L. mittermeieri. We studied individuals from early March to the end of June 2015 and 2016, in three sites of the Ampasindava peninsula. We radio‐tracked 15 individuals to obtain detailed information on the size and location of home ranges (around 450 hr of tracking). Direct observation and morphometric measurements provided additional data sets. Both kernel density estimation (KDE) and minimum convex polygon (MCP) methods yielded similar home range sizes (an average of 2.01 ha with KDE method and 1.96 ha with MCP method). We did not find differences in home range size between males and females, with respect to forest type or proximity to the forest edge. Home ranges overlapped and individuals showed low levels of territoriality. We highlighted a sexually‐dimorphic trait: males have longer upper canine than females. Our results constitute the first set of ecological information on Lepilemur mittermeieri and could be the basis for a conservation strategy for this endangered species with a very small distribution area.Peer reviewe
Vermeulen Cédric - One of the best experts on this subject based on the ideXlab platform.
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Data on the diet of Lepilemur mittermeieri, a sportive lemur endemic to the northwest of Madagascar
2020Co-Authors: Wilmet Leslie, Devillers Pierre, Vermeulen Cédric, Beudels-jamar, Roseline C.Abstract:Mittermeier’s sportive lemur (Lepilemur mittermeieri) is an endangered primate endemic to the Ampasindava peninsula, in north-west Madagascar. Lepilemur are known to be folivores with a low metabolic rate, but no specific investigation of the diet of Mittermeier’s sportive lemur has been reported. In 2015 and 2016, we conducted a field study of the species in two areas of the Ampasindava peninsula, involving direct observation of individuals equipped with radio-collars. We verified that Mittermeier’s sportive lemur is a solitary forager. We identified a total of 77 tree species consumed and a large variation in the spectrum of species used within the two studied sites. Most of the plant material consumed was made of leaves, with few fruits.Peer reviewe
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Data on the diet of Lepilemur mittermeieri, a sportive lemur endemic to the northwest of Madagascar
Madagascar Section of the IUCN SSC Primate Specialist Group, 2020Co-Authors: Wilmet Leslie, Devillers Pierre, Vermeulen Cédric, Beudels-jamar, Roseline C.Abstract:peer reviewedaudience: researcher, professional, studentMittermeier’s sportive lemur (Lepilemur mittermeieri) is an endangered primate endemic to the Ampasindava peninsula, in north-west Madagascar. Lepilemur are known to be folivores with a low metabolic rate, but no specific investigation of the diet of Mittermeier’s sportive lemur has been reported. In 2015 and 2016, we conducted a field study of the species in two areas of the Ampasindava peninsula, involving direct observation of individuals equipped with radio-collars. We verified that Mittermeier’s sportive lemur is a solitary forager. We identified a total of 77 tree species consumed and a large variation in the spectrum of species used within the two studied sites. Most of the plant material consumed was made of leaves, with few fruits
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Use of space and home range characteristics of Lepilemur mittermeieri, an endangered sportive lemur endemic to the Ampasindava peninsula, north‐west Madagascar
2019Co-Authors: Wilmet Leslie, Schwitzer Christoph, Devillers Pierre, Beudels-jamar, Roseline C., Rakotondrainibe Hajanirina, Vermeulen CédricAbstract:Lepilemur mittermeieri, a little‐studied sportive lemur of north‐west Madagascar, endemic to the Ampasindava Peninsula, faces habitat loss through forest degradation and rapid fragmentation. Understanding its habitat requirement is the first step toward preservation of this threatened forest‐dependent species. In this study, we gathered data on the use of space and home range characteristics of L. mittermeieri. We studied individuals from early March to the end of June 2015 and 2016, in three sites of the Ampasindava peninsula. We radio‐tracked 15 individuals to obtain detailed information on the size and location of home ranges (around 450 hr of tracking). Direct observation and morphometric measurements provided additional data sets. Both kernel density estimation (KDE) and minimum convex polygon (MCP) methods yielded similar home range sizes (an average of 2.01 ha with KDE method and 1.96 ha with MCP method). We did not find differences in home range size between males and females, with respect to forest type or proximity to the forest edge. Home ranges overlapped and individuals showed low levels of territoriality. We highlighted a sexually‐dimorphic trait: males have longer upper canine than females. Our results constitute the first set of ecological information on Lepilemur mittermeieri and could be the basis for a conservation strategy for this endangered species with a very small distribution area.Peer reviewe
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Field Data on the Little Known and Endangered Lepilemur mittermeieri
2017Co-Authors: Wilmet Leslie, Schwitzer C., Devillers P., Beudels-jamar R. C., Sonet G., Vermeulen CédricAbstract:Lepilemur mittermeieri is a very little known sportive lemur of the Ampasindava peninsula of Madagascar, presently regarded as Endangered. It was described in 2006 by Rabarivola et al. on the basis of genetic material only, obtained from three individuals collected at the same locality. No observation confidently allocated to the species has been reported since. The objectives of our research were to verify that the sportive lemurs found in forests of the Ampasindava peninsula beyond the type locality of Lepilemur mittermeieri belonged to the same species as the type, to provide morphological and behavioral data for populations confidently attributed to L. mittermeieri and to obtain for these populations preliminary evaluations of density variations within the peninsula. Our surveys were undertaken in March and April 2014 in remnant forest patches of the western part of the Ampasindava peninsula. Linear transects by night and punctual observations by day were conducted. A total of 54 animals were seen along nine transects situated in four forest patches, two at low altitude and two at high altitude. All animals examined and photographed appeared similar, and the impression was gained that a single taxon was involved. Genetic material collected from one dead specimen proved identical to the type of L. mittermeieri which confirmed the identity of the populations we observed. It thus appears that L. mittermeieri is indeed the only sportive lemur present on the peninsula and that it occurs in several forest remnants. We endeavored to get evaluations of the density and abundance of the species in the four forest patches we studied. We used KAIs (Kilometric Abundance Indices) to evaluate and compare relative densities, and Buckland's distance sampling method to evaluate absolute densities. The latter suggested a density of 1.9 animals/ha, a result that must, however, be taken with caution.Peer reviewe
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Utilisation de l'habitat d'une espèce menacée dans le nord-ouest de Madagascar - Lepilemur mittermeieri
2016Co-Authors: Wilmet Leslie, Devillers Pierre, Vermeulen Cédric, Schwitzer ChristophAbstract:Biodiversity and endemism is very high in Madagascar and Genus Lepilemur is part of the endemic mammalian fauna of the island. Sportive lemurs have small distribution ranges, fairly small total populations and are particularly negatively affected by deforestation and habitat fragmentation, serious threats for the biological diversity of the island. Our research focus on one poorly-known taxon, Lepilemur mittermeieri. The distribution range of this endangered species is restricted to the Ampasindava peninsula in the northwest Madagascar and ecological information is essential for its preservation. The main objective of our study is to analyze habitat use and niche characteristics of the species and the impact of habitat degradation and fragmentation on these parameters in order to design robust conservation guidelines for the Ampasindava peninsula. In this talk, we will present the project as a whole and results of two 4-months field missions conducted in 2015 and in 2016. These field missions were designed to specifically 1)compare home range size between two sites 2)complete forest characterization of the home range of several radio-collared individuals. The methodology includes the monitoring of 16animals equipped with radio-collar (VHS telemetry) during 6hours per night for a number of days, GPS locations being recorded every 10 minutes. The home range is derived from the telemetry observation through MCP method
Schwitzer Christoph - One of the best experts on this subject based on the ideXlab platform.
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Updated population density estimation and distribution range of the Critically Endangered Sahamalaza sportive lemur, Lepilemur sahamalaza
Madagascar Section of the IUCN SSC Primate Specialist Group, 2020Co-Authors: Mandl Isabella, Schwitzer Christoph, Rabemanajara Naina, Wilmet LeslieAbstract:peer reviewedaudience: researcher, professional, studentAccurate population density estimates are important for effective conservation measures of endangered species. For the Critically Endangered Sahalamaza sportive lemur (Lepilemur sahamalaza), no recent or robust population estimates are available, complicating conservation management of this species. This study examined the species distribution range as well as assessing population density in the range of occurrence with standardized methodology (transect walks and home range calculations) between 2013 and 2016. The results suggest that Sahamalaza sportive lemurs are confined to the Sahamalaza Peninsula. Population density ranges between 1.49 to 1.87 individuals/ha depending on the methodology used to estimate density. Population size estimates consequently vary between 3800 and 4700 remaining individuals of this species, subject to a re-evaluation of the remaining habitat
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Updated population density estimation and distribution range of the Critically Endangered Sahamalaza sportive lemur, Lepilemur sahamalaza
2020Co-Authors: Mandl Isabella, Schwitzer Christoph, Rabemanajara Naina, Wilmet LeslieAbstract:Accurate population density estimates are important for effective conservation measures of endangered species. For the Critically Endangered Sahalamaza sportive lemur (Lepilemur sahamalaza), no recent or robust population estimates are available, complicating conservation management of this species. This study examined the species distribution range as well as assessing population density in the range of occurrence with standardized methodology (transect walks and home range calculations) between 2013 and 2016. The results suggest that Sahamalaza sportive lemurs are confined to the Sahamalaza Peninsula. Population density ranges between 1.49 to 1.87 individuals/ha depending on the methodology used to estimate density. Population size estimates consequently vary between 3800 and 4700 remaining individuals of this species, subject to a re-evaluation of the remaining habitat.Peer reviewe
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Use of space and home range characteristics of Lepilemur mittermeieri, an endangered sportive lemur endemic to the Ampasindava peninsula, north‐west Madagascar
2019Co-Authors: Wilmet Leslie, Schwitzer Christoph, Devillers Pierre, Beudels-jamar, Roseline C., Rakotondrainibe Hajanirina, Vermeulen CédricAbstract:Lepilemur mittermeieri, a little‐studied sportive lemur of north‐west Madagascar, endemic to the Ampasindava Peninsula, faces habitat loss through forest degradation and rapid fragmentation. Understanding its habitat requirement is the first step toward preservation of this threatened forest‐dependent species. In this study, we gathered data on the use of space and home range characteristics of L. mittermeieri. We studied individuals from early March to the end of June 2015 and 2016, in three sites of the Ampasindava peninsula. We radio‐tracked 15 individuals to obtain detailed information on the size and location of home ranges (around 450 hr of tracking). Direct observation and morphometric measurements provided additional data sets. Both kernel density estimation (KDE) and minimum convex polygon (MCP) methods yielded similar home range sizes (an average of 2.01 ha with KDE method and 1.96 ha with MCP method). We did not find differences in home range size between males and females, with respect to forest type or proximity to the forest edge. Home ranges overlapped and individuals showed low levels of territoriality. We highlighted a sexually‐dimorphic trait: males have longer upper canine than females. Our results constitute the first set of ecological information on Lepilemur mittermeieri and could be the basis for a conservation strategy for this endangered species with a very small distribution area.Peer reviewe
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Utilisation de l'habitat d'une espèce menacée dans le nord-ouest de Madagascar - Lepilemur mittermeieri
2016Co-Authors: Wilmet Leslie, Devillers Pierre, Vermeulen Cédric, Schwitzer ChristophAbstract:Biodiversity and endemism is very high in Madagascar and Genus Lepilemur is part of the endemic mammalian fauna of the island. Sportive lemurs have small distribution ranges, fairly small total populations and are particularly negatively affected by deforestation and habitat fragmentation, serious threats for the biological diversity of the island. Our research focus on one poorly-known taxon, Lepilemur mittermeieri. The distribution range of this endangered species is restricted to the Ampasindava peninsula in the northwest Madagascar and ecological information is essential for its preservation. The main objective of our study is to analyze habitat use and niche characteristics of the species and the impact of habitat degradation and fragmentation on these parameters in order to design robust conservation guidelines for the Ampasindava peninsula. In this talk, we will present the project as a whole and results of two 4-months field missions conducted in 2015 and in 2016. These field missions were designed to specifically 1)compare home range size between two sites 2)complete forest characterization of the home range of several radio-collared individuals. The methodology includes the monitoring of 16animals equipped with radio-collar (VHS telemetry) during 6hours per night for a number of days, GPS locations being recorded every 10 minutes. The home range is derived from the telemetry observation through MCP method
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Le Parc National Sahamalaza - Iles Radama serait-il l’ultime refuge pour certaines espèces de lémuriens du nord-ouest de Madagascar ?
Agri-Overseas, 2015Co-Authors: Wilmet Leslie, Schwitzer Christoph, Devillers Pierre, Beudels-jamar, Roseline C., Vermeulen CédricAbstract:peer reviewedaudience: researcher, professional, student, popularizationDepuis des millions d’années, la faune et la flore terrestre de Madagascar ont évolué dans un espace isolé. Suite à cette situation, le niveau d’endémisme y est très élevé et l’ensemble de l’île représente un des plus importants hotspot de biodiversité. Madagascar fait aussi partie des pays les plus touchés en termes de destruction des habitats naturels ; 90 % de la végétation d’origine est aujourd’hui perdue. La déforestation et la fragmentation des habitats forestiers menace particulièrement les primates de l’île, les lémuriens. L’île est considérée par de nombreuses organisations internationales comme une priorité pour la conservation de la nature, autant dans le domaine zoologique que botanique. Les premières aires protégées de Madagascar ont été établies en 1927 et l’île en compte aujourd’hui 47. Cet article reprend l’historique et fait l’état des lieux du parc national Sahamalaza-Ile Radama, situé au nord-ouest de Madagascar. Nous nous intéressons spécifiquement à deux espèces de lémuriens emblématiques du parc ; Eulemur flavifrons et Lepilemur sahamalazensis ainsi qu’aux menaces qui pèsent sur leur écosystème. Différentes mesures ont été proposées dans le cadre d’un Plan d’Action de Conservation afin d’en améliorer la gestion et assurer la survie de ces espèces.Niche conservatism and conservation biology of Lepilemur in northwest Madagasca
Roland Hilgartner - One of the best experts on this subject based on the ideXlab platform.
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vorgelegt von
2014Co-Authors: Der Fakultät, Naturwissenschaften Universität Ulm, Roland Hilgartner, Erster Gutachter, Dritter Gutachter, D. Zinner, T. Pietsch, J. U. GanzhornAbstract:Living apart together: Pair-living in red-tailed sportive lemurs (Lepilemur ruficaudatus
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Coordination in Red-Tailed Sportive Lemurs (Lepilemur ruficaudatus)
2013Co-Authors: Claudia Fichtel, Roland Hilgartner, Walter Zucchini, C. Fichtel, R. HilgartnerAbstract:# The Author(s) 2011. This article is published with open access at Springerlink.com Abstract Many animals are organized into social groups and have to synchronize their activities to maintain group cohesion. Although activity budgets, habitat constraints, and group properties may impact on behavioural synchrony, little is known regarding how members of a group reach a consensus on the timing of activities such as foraging bouts. Game theory predicts that pair partners should synchronize their activities when there is an advantage of foraging together. As a result of this synchronization, differences in the energetic reserves of the two players develop spontaneously and the individual with lower reserves emerges as a pacemaker of the synchrony. Here, we studied the behavioral synchrony of pairliving, nocturnal, red-tailed sportive lemurs (Lepilemur ruficaudatus). We observed 8 pairs continuously for ≥1 annual reproductive cycle in Kirindy Forest, Western Madagascar. During focal observations, one observer followed the female of a pair and, simultaneously, another observer followed the male. We recorded the location and behavioral state of the focal individual every 5 min via instantaneous sampling
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determinants of pair living in red tailed sportive lemurs Lepilemur ruficaudatus
Ethology, 2012Co-Authors: Roland Hilgartner, Peter M. Kappeler, Claudia Fichtel, Dietmar ZinnerAbstract:Pair-living and a monogamous mating strategy are rare and theoretically unexpected among mammals. Nevertheless, about 10% of primate species exhibit such a social system, which is difficult to explain in the absence of paternal care. In this study, we investigated the two major hypotheses proposed to explain the evolution of monogamy in mammals, the female defence hypothesis (FDH) and the resource defence hypothesis (RDH), in red-tailed sportive lemurs (Lepilemur ruficaudatus), a nocturnal primate from Madagascar. We analysed behavioural data from eight male‐female pairs collected during a 24-mo field study to illuminate the determinants of pair-living in this species. Male and female L. ruficaudatus were found to live in dispersed pairs, which are characterised by low cohesion and low encounter rates within a common home range. Social interactions between pair partners were mainly agonistic and characterised by a complete absence of affiliative interactions ‐ body contact was only observed during mating. During the short annual mating season, males exhibited elevated levels of aggression towards mates, as well as extensive mate guarding and increased locomotor activity. In addition, males were exclusively responsible for the maintenance of proximity between pair partners during this period, and they defended their territories against neighbouring males but not against females. Together, these results point towards the importance of female defence in explaining pair-living in L. ruficaudatus. We discuss the spatial and temporal distribution of receptive females in relation to the female defence strategies of males and suggest possible costs that prevent male red-tailed sportive lemurs from defending more than one female.
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noises in the dark vocal communication in Lepilemur ruficaudatus and other nocturnal pair living primates
2012Co-Authors: Claudia Fichtel, Roland HilgartnerAbstract:Although the number of pair-living species is higher in nocturnal than in diurnal primates, less is known about the communicative function of their vocalizations. One striking feature of vocal communication in diurnal pair-living primates is that partners exchange vocalizations in coordinated duets. Several functions have been attributed to duets, including mate attraction, advertizing and strengthening the pair bond, and territorial defense. To assess whether these functions can also be attributed to vocalizations of pair-living nocturnal primates, we studied the communicative function of vocalizations of red-tailed sportive lemurs (Lepilemur ruficaudatus). Social interactions between partners were equally often accompanied by vocal exchanges or not. Half of these vocal interactions included mutual but not coordinated exchanges of vocalizations between partners. In addition, playback experiments with vocalizations of the respective partner did not elicit vocal responses. Thus, exchanges of vocalizations might function to regulate spacing and interactions within pairs rather than to advertize or strengthen pair bonds. Since Lepilemur ruficaudatus interacted more often vocally with partners than with neighbors, and also vocalized when alone, we conclude that calling serves to signal an animal’s presence in its territory and to regulate spacing among conspecifics. Because vocalizations seem to serve in territorial defense in most nocturnal pair-living primates, cohesiveness between partners may have been the initial driving force behind the evolution of duets.
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life history traits and parental care in Lepilemur ruficaudatus
American Journal of Primatology, 2008Co-Authors: Roland Hilgartner, Dietmar Zinner, Peter M. KappelerAbstract:In this study we investigated the importance of biparental care for the evolution and/or maintenance of pair-living in red-tailed sportive lemurs (Lepilemur ruficaudatus), a nocturnal folivorous lemur. Between 2000 and 2005, we collected data on life history traits from a total of 14 radio-collared pairs of adults and their offspring in Kirindy forest, western Madagascar. Predation rate varied between years with a minimum of 0% and a maximum of 40% per year. Patterns of parental care were quantified during simultaneous focal observations of both pair-partners in 2003 and 2004. Mating activity was limited to the months of May and June, as indicated by conspicuous changes of vulval morphology and male mate guarding behavior. After a gestation length of about 5 months, which is much longer than expected for a lemur of this body mass, single infants were born in November. Lactation lasted for about 50 days. Apart from lactation, females provided infant care by warming, grooming and transporting infants orally. Infants were parked in dense vegetation while females foraged. Males were seen only rarely in proximity to infants and we found no evidence for direct infant care provided by social fathers. We conclude that the necessity of direct infant care cannot explain the evolution and/or maintenance of pair-living in Lepilemur ruficaudatus. Am. J. Primatol. 70:2–11, 2008. © 2007 Wiley-Liss, Inc.
Jorg U Ganzhorn - One of the best experts on this subject based on the ideXlab platform.
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molecular phylogeny and taxonomic revision of the sportive lemurs Lepilemur primates
BMC Evolutionary Biology, 2006Co-Authors: Nicole Andriaholinirina, Jorg U Ganzhorn, Urs Thalmann, Jean-luc Fausser, Christian Roos, Dietmar Zinner, Clément Rabarivola, Iary Ravoarimanana, Bernhard Meier, Roland HilgartnerAbstract:The number of species within the Malagasy genus Lepilemur and their phylogenetic relationships is disputed and controversial. In order to establish their evolutionary relationships, a comparative cytogenetic and molecular study was performed. We sequenced the complete mitochondrial cytochrome b gene (1140 bp) from 68 individuals representing all eight sportive lemur species and most major populations, and compared the results with those obtained from cytogenetic studies derived from 99 specimens. Interspecific genetic variation, diagnostic characters and significantly supported phylogenetic relationships were obtained from the mitochondrial sequence data and are in agreement with cytogenetic information. The results confirm the distinctiveness of Lepilemur ankaranensis, L. dorsalis, L. edwardsi, L. leucopus, L. microdon, L. mustelinus, L. ruficaudatus and L. septentrionalis on species level. Additionally, within L. ruficaudatus large genetic differences were observed among different geographic populations. L. dorsalis from Sahamalaza Peninsula and from the Ambanja/Nosy Be region are paraphyletic, with the latter forming a sister group to L. ankaranensis. Our results support the classification of the eight major sportive lemur taxa as independent species. Moreover, our data indicate further cryptic speciation events within L. ruficaudatus and L. dorsalis. Based on molecular data we propose to recognize the sportive lemur populations from north of the Tsiribihina River, south of the Betsiboka River, and from the Sahamalaza Peninsula, as distinct species.
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Molecular phylogeny and taxonomic revision of the sportive lemurs (Lepilemur, Primates)
BMC Evolutionary Biology, 2006Co-Authors: Nicole Andriaholinirina, Jorg U Ganzhorn, Urs Thalmann, Jean-luc Fausser, Christian Roos, Dietmar Zinner, Clément Rabarivola, Iary Ravoarimanana, Bernhard Meier, Roland HilgartnerAbstract:Background The number of species within the Malagasy genus Lepilemur and their phylogenetic relationships is disputed and controversial. In order to establish their evolutionary relationships, a comparative cytogenetic and molecular study was performed. We sequenced the complete mitochondrial cytochrome b gene (1140 bp) from 68 individuals representing all eight sportive lemur species and most major populations, and compared the results with those obtained from cytogenetic studies derived from 99 specimens. Results Interspecific genetic variation, diagnostic characters and significantly supported phylogenetic relationships were obtained from the mitochondrial sequence data and are in agreement with cytogenetic information. The results confirm the distinctiveness of Lepilemur ankaranensis , L. dorsalis , L. edwardsi , L. leucopus , L. microdon , L. mustelinus , L. ruficaudatus and L. septentrionalis on species level. Additionally, within L. ruficaudatus large genetic differences were observed among different geographic populations. L. dorsalis from Sahamalaza Peninsula and from the Ambanja/Nosy Be region are paraphyletic, with the latter forming a sister group to L. ankaranensis . Conclusion Our results support the classification of the eight major sportive lemur taxa as independent species. Moreover, our data indicate further cryptic speciation events within L. ruficaudatus and L. dorsalis . Based on molecular data we propose to recognize the sportive lemur populations from north of the Tsiribihina River, south of the Betsiboka River, and from the Sahamalaza Peninsula, as distinct species.
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selection of food and ranging behaviour in a sexually monomorphic folivorous lemur Lepilemur ruficaudatus
Journal of Zoology, 2004Co-Authors: Jorg U Ganzhorn, Jutta Schmid, Thomas Pietsch, Joanna Fietz, Sabine Gross, Nathalie SteinerAbstract:Monomorphic lemurs of Madagascar allow us to investigate whether there are behavioural mechanisms that compensate for sex-specific differences in the costs of maintenance and reproduction in arboreal primates. Food selection of the pair-living Lepilemur ruficaudatus was studied in relation to food chemistry, and travel distances were measured as possible indications of differential investment in ranging activities (possibly related to the defence of territories and/or mating opportunities). Fourteen females and 14 males were radio-tracked for a total of 365 half-nights (from dusk to midnight or from midnight to dawn) at different times of the year (birth, lactation and weaning, pre-mating, post-mating). When based on monthly means, the two sexes did not differ in nightly travel distances. Food selection of females and males did not differ in relation to the chemical composition of leaves, but fruits consumed by females had lower fibre contents than fruits consumed by males. Even though other behavioural data are fragmentary, little evidence exists for behavioural mechanisms in L. ruficaudatus to compensate for the different energetic costs of females and males.
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social organization of Lepilemur ruficaudatus
International Journal of Primatology, 2003Co-Authors: Dietmar Zinner, Peter M. Kappeler, Roland Hilgartner, Thomas Pietsch, Jorg U GanzhornAbstract:We characterize the spatial organization of red-tailed sportive lemurs (Lepilemur ruficaudatus) as a key aspect of their social organization and social system. Sportive lemurs are small (<1000 g), nocturnal and folivorous primates endemic to Madagascar. We studied a population of 57 individually-marked individuals in Kirindy Forest, western Madagascar, between 1995 and 2001. We radio-tracked 20 males and 26 females of the marked population to obtain detailed information on the size and location of their home ranges. Census data and morphometric measurements provided complementary data sets. Males and females occupied small (<1 ha) home-ranges. Long-term records from 9 individuals revealed home-range stability over several years. In 4 cases home ranges overlapped extensively with that of one member of the opposite sex; in 2 cases, a spatial association of 1 male and 2 females occurred. However, home ranges overlapped very little with neighboring individuals of both sexes. During the study period, spatially associated individuals used on average 5.6 sleeping trees within 117 days, but they spent on average only about every fourth night together. The data suggest that home ranges in red-tailed sportive lemurs are exclusively used by pairs or trios and that the modal social organization of red-tailed sportive lemurs is pair-living.
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genetic differentiation among natural populations of Lepilemur ruficaudatus
International Journal of Primatology, 2000Co-Authors: Lutz Bachmann, Y Rumpler, Jorg U Ganzhorn, Jurgen TomiukAbstract:We studied the genetic differentiation of five populations of red-tailed sportive lemur Lepilemur ruficaudatus by means of allozyme variability and RAPD polymorphisms in order to test whether the Tsiribihina River separates the distribution areas of Lepilemur ruficaudatus and and L. edwardsi. Genetic data as well as the karyotype of a male individual clearly indicate that the Andramasay Forest in the north of Tsiribihina River is inhabited by Lepilemur ruficaudatus and not by L. edwardsi. We propose that the distribution of the two species are separated by the Manambolo River. However, the northernmost population of Lepilemur ruficaudatus inhabiting the Andramasay Forest is gentically differentiated from those that inhabit the dry forest in the south of Tsiribihina River.