The Experts below are selected from a list of 207 Experts worldwide ranked by ideXlab platform
Elke Zimmermann - One of the best experts on this subject based on the ideXlab platform.
-
Are sleeping site ecology and season linked to intestinal helminth prevalence and diversity in two sympatric, nocturnal and arboreal primate hosts (LepiLemur edwardsi and Avahi occidentalis)?
BMC Ecology, 2018Co-Authors: May Hokan, Bertrand Andriatsitohaina, Ute Radespiel, Elke Zimmermann, Solofonirina RasoloharijaonaAbstract:Background Various factors, such as climate, body size and sociality are often linked to parasitism. This constrains the identification of other determinants driving parasite infections. Here, we investigate for the first time intestinal parasites in two sympatric arboreal primate species, which share similar activity patterns, feeding ecology, body size and sociality, and cope with the same climate conditions, but differ in sleeping site ecology: the Milne-Edward’s Sportive Lemur ( LepiLemur edwardsi ) and the Western woolly Lemur ( Avahi occidentalis ). Comparison of these two species aimed to test whether differences in sleeping sites are related to differences in parasite infection patterns. Additionally, gender and seasonal factors were taken into account. Animals were radio-collared to record their sleeping site dynamics and to collect fecal samples to assess intestinal parasitism during both the dry and the rainy season. Results Only low parasite diversity was detected, which is attributable to the strict arboreal lifestyle of these Lemurs, limiting their contact with infective parasite stages. L. edwardsi , which sleeps in tree holes and repeatedly uses the same sleeping site, excreted eggs of strongyle and oxyurid nematodes, whereby strongyles always occurred in coinfection with oxyurids. In contrast, A. occidentalis , which sleeps on open branches and frequently changes sleeping sites, only excreted eggs of strongyle nematodes. This difference can be attributed to a potential favorable environment presented by tree holes for infective stages, facilitating parasitic transmission. Additionally, Strongylida in A. occidentalis were only observed in the rainy season, suggesting an arrested development during the dry season in the nematodes’ life cycle. Males and females of both Lemur species showed the same frequency of parasitism. No differences in body mass of infected and non-infected individuals were observed, indicating that the animals’ body condition remains unaffected by the detected gastrointestinal parasites. Conclusions The comparison of two primate hosts with a very similar lifestyle suggests an influence of the sleeping site ecology on intestinal parasites. In A. occidentalis there was a clear seasonal difference in strongyle egg excretion. These results improve our understanding of the parasite ecology in these endangered primate species, which may be critical in the light of species conservation.
-
Are sleeping site ecology and season linked to intestinal helminth prevalence and diversity in two sympatric, nocturnal and arboreal primate hosts (LepiLemur edwardsi and Avahi occidentalis)?
BMC Ecology, 2018Co-Authors: May Hokan, Bertrand Andriatsitohaina, Solofonirina Rasoloharijaona, Ute Radespiel, Elke Zimmermann, Christina StrubeAbstract:Background Various factors, such as climate, body size and sociality are often linked to parasitism. This constrains the identification of other determinants driving parasite infections. Here, we investigate for the first time intestinal parasites in two sympatric arboreal primate species, which share similar activity patterns, feeding ecology, body size and sociality, and cope with the same climate conditions, but differ in sleeping site ecology: the Milne-Edward’s Sportive Lemur ( LepiLemur edwardsi ) and the Western woolly Lemur ( Avahi occidentalis ). Comparison of these two species aimed to test whether differences in sleeping sites are related to differences in parasite infection patterns. Additionally, gender and seasonal factors were taken into account. Animals were radio-collared to record their sleeping site dynamics and to collect fecal samples to assess intestinal parasitism during both the dry and the rainy season. Results Only low parasite diversity was detected, which is attributable to the strict arboreal lifestyle of these Lemurs, limiting their contact with infective parasite stages. L. edwardsi , which sleeps in tree holes and repeatedly uses the same sleeping site, excreted eggs of strongyle and oxyurid nematodes, whereby strongyles always occurred in coinfection with oxyurids. In contrast, A. occidentalis , which sleeps on open branches and frequently changes sleeping sites, only excreted eggs of strongyle nematodes. This difference can be attributed to a potential favorable environment presented by tree holes for infective stages, facilitating parasitic transmission. Additionally, Strongylida in A. occidentalis were only observed in the rainy season, suggesting an arrested development during the dry season in the nematodes’ life cycle. Males and females of both Lemur species showed the same frequency of parasitism. No differences in body mass of infected and non-infected individuals were observed, indicating that the animals’ body condition remains unaffected by the detected gastrointestinal parasites. Conclusions The comparison of two primate hosts with a very similar lifestyle suggests an influence of the sleeping site ecology on intestinal parasites. In A. occidentalis there was a clear seasonal difference in strongyle egg excretion. These results improve our understanding of the parasite ecology in these endangered primate species, which may be critical in the light of species conservation.
-
Sleeping site ecology, but not sex, affect ecto- and hemoparasite risk, in sympatric, arboreal primates (Avahi occidentalis and LepiLemur edwardsi)
Frontiers in Zoology, 2017Co-Authors: May Hokan, Ute Radespiel, Christina Strube, Elke ZimmermannAbstract:Background A central question in evolutionary parasitology is to what extent ecology impacts patterns of parasitism in wild host populations. In this study, we aim to disentangle factors influencing the risk of parasite exposure by exploring the impact of sleeping site ecology on infection with ectoparasites and vector-borne hemoparasites in two sympatric primates endemic to Madagascar. Both species live in the same dry deciduous forest of northwestern Madagascar and cope with the same climatic constraints, they are arboreal, nocturnal, cat-sized and pair-living but differ prominently in sleeping site ecology. The Western woolly Lemur ( Avahi occidentalis ) sleeps on open branches and frequently changes sleeping sites, whereas the Milne-Edward’s Sportive Lemur ( LepiLemur edwardsi ) uses tree holes, displaying strong sleeping site fidelity. Sleeping in tree holes should confer protection from mosquito-borne hemoparasites, but should enhance the risk for ectoparasite infestation with mites and nest-adapted ticks. Sex may affect parasite risk in both species comparably, with males bearing a higher risk than females due to an immunosuppressive effect of higher testosterone levels in males or to sex-specific behavior. To explore these hypotheses, ectoparasites and blood samples were collected from 22 individuals of A. occidentalis and 26 individuals of L. edwardsi during the dry and rainy season. Results L. edwardsi, but not A. occidentalis , harbored ectoparasites, namely ticks ( Haemaphysalis Lemuris [Ixodidae], Ornithodoros sp. [Argasidae]) and mites ( Aetholaelaps trilyssa , [Laelapidae]), suggesting that sleeping in tree holes promotes infestation with ectoparasites. Interestingly, ectoparasites were found solely in the hot, rainy season with a prevalence of 75% ( N = 16 animals). Blood smears were screened for the presence and infection intensity of hemoparasites. Microfilariae were detected in both species. Morphological characteristics suggested that each Lemur species harbored two different filarial species. Prevalence of microfilarial infection was significantly lower in L. edwardsi than in A. occidentalis. No significant difference in infection intensity between the two host species, and no effect of season, daytime of sampling or sex on prevalence or infection intensity was found. In neither host species, parasite infection showed an influence on body weight as an indicator for body condition. Conclusions Our findings support that sleeping site ecology affects ectoparasite infestation in nocturnal, arboreal mammalian hosts in the tropics, whereas there is no significant effect of host sex. The influence of sleeping site ecology to vector-borne hemoparasite risk is less pronounced. The observed parasite infections did not affect body condition and thus may be of minor importance for shaping reproductive fitness. Findings provide first evidence for the specific relevance of sleeping site ecology on parasitism in arboreal and social mammals. Further, our results increase the sparse knowledge on ecological drivers of primate host-parasite interactions and transmission pathways in natural tropical environments.
-
sleeping site ecology but not sex affect ecto and hemoparasite risk in sympatric arboreal primates avahi occidentalis and lepiLemur edwardsi
Frontiers in Zoology, 2017Co-Authors: May Hokan, Ute Radespiel, Christina Strube, Elke ZimmermannAbstract:A central question in evolutionary parasitology is to what extent ecology impacts patterns of parasitism in wild host populations. In this study, we aim to disentangle factors influencing the risk of parasite exposure by exploring the impact of sleeping site ecology on infection with ectoparasites and vector-borne hemoparasites in two sympatric primates endemic to Madagascar. Both species live in the same dry deciduous forest of northwestern Madagascar and cope with the same climatic constraints, they are arboreal, nocturnal, cat-sized and pair-living but differ prominently in sleeping site ecology. The Western woolly Lemur (Avahi occidentalis) sleeps on open branches and frequently changes sleeping sites, whereas the Milne-Edward’s Sportive Lemur (LepiLemur edwardsi) uses tree holes, displaying strong sleeping site fidelity. Sleeping in tree holes should confer protection from mosquito-borne hemoparasites, but should enhance the risk for ectoparasite infestation with mites and nest-adapted ticks. Sex may affect parasite risk in both species comparably, with males bearing a higher risk than females due to an immunosuppressive effect of higher testosterone levels in males or to sex-specific behavior. To explore these hypotheses, ectoparasites and blood samples were collected from 22 individuals of A. occidentalis and 26 individuals of L. edwardsi during the dry and rainy season. L. edwardsi, but not A. occidentalis, harbored ectoparasites, namely ticks (Haemaphysalis Lemuris [Ixodidae], Ornithodoros sp. [Argasidae]) and mites (Aetholaelaps trilyssa, [Laelapidae]), suggesting that sleeping in tree holes promotes infestation with ectoparasites. Interestingly, ectoparasites were found solely in the hot, rainy season with a prevalence of 75% (N = 16 animals). Blood smears were screened for the presence and infection intensity of hemoparasites. Microfilariae were detected in both species. Morphological characteristics suggested that each Lemur species harbored two different filarial species. Prevalence of microfilarial infection was significantly lower in L. edwardsi than in A. occidentalis. No significant difference in infection intensity between the two host species, and no effect of season, daytime of sampling or sex on prevalence or infection intensity was found. In neither host species, parasite infection showed an influence on body weight as an indicator for body condition. Our findings support that sleeping site ecology affects ectoparasite infestation in nocturnal, arboreal mammalian hosts in the tropics, whereas there is no significant effect of host sex. The influence of sleeping site ecology to vector-borne hemoparasite risk is less pronounced. The observed parasite infections did not affect body condition and thus may be of minor importance for shaping reproductive fitness. Findings provide first evidence for the specific relevance of sleeping site ecology on parasitism in arboreal and social mammals. Further, our results increase the sparse knowledge on ecological drivers of primate host-parasite interactions and transmission pathways in natural tropical environments.
-
duetting a mechanism to strengthen pair bonds in a dispersed pair living primate lepiLemur edwardsi
American Journal of Physical Anthropology, 2009Co-Authors: Maria Mendezcardenas, Elke ZimmermannAbstract:Duetting is defined as an interactively organized pair display in which one pair partner coordinates its vocalizations in time with those of the other. It is widespread among tropical birds and cohesive pair-living primates, in which it is suggested to strengthen pair bonds. We know very little about the presence and function of duetting in dispersed pair-living mammals. We studied duetting behavior in a solitary foraging, but pair-sleeping, primate, the Milne Edwards' Sportive Lemur, in a dry deciduous forest of north-western Madagascar. We radio-tracked six pairs throughout 1 year and recorded their sleeping sites and associations, home-range use, and vocal and behavioral interactions. Three different periods were covered (mating, pregnancy, and offspring care). Sleeping partners form long-term pair bonds, indicated by an almost exclusive pair-specific usage of sleeping sites and home-ranges across periods. We explored three functional hypothesis of duetting: mate reunion, pair reunion, and joint-territorial defense. Pairs regularly engaged in duet calling. Duetting increased significantly during the offspring care period. Duetting occurred significantly more often at feeding sites than at sleeping sites. Pair partners synchronized behavioral activities after duetting. The activity most often synchronized was locomotion. Pair partners played an equal role in duetting with no difference between sexes in starting or terminating duetting. Altogether, our results provide support for the hypothesis that in dispersed pair-living primates, duetting evolved as a mechanism to coordinate activities between pair partners dispersed in space, to strengthen pair bonds, and, perhaps, to limit infanticide and nutritional stress in lactating females.
Christoph Schwitzer - One of the best experts on this subject based on the ideXlab platform.
-
sahamalaza Sportive Lemur lepiLemur sahamalaza vocal communication call use context and gradation
Folia Primatologica, 2019Co-Authors: Isabella Mandl, Christoph Schwitzer, Marc W HolderiedAbstract:Stereotypical vocalisations can facilitate long-distance communication in dense and, thus, sound-degrading forest habitats. Despite this, primate vocal repertoires often also include gradations between different call types that are used in social interactions. Because many nocturnal primates show a solitary social structure, it has been difficult to assess the role vocalisations play in mediating their social encounters. Here we aim to expand on the call types of Sahamalaza Sportive Lemurs, LepiLemur sahamalaza, as well as investigate their variability and use in social contexts. Through long-term behavioural observations with concurrent recording of vocalisations of known and unknown individuals between 2015 and 2016, we described three previously unrecorded calls and expanded the vocal repertoire to 12 different call types that were used in both targeted social and broadcast solitary contexts. Linear discriminant function and cluster analysis supported initial observations that vocalisations within call types were variable and that at least two call types can be classified as "graded," contrary to expectations. Despite variations in call-context connections, no clear patterns of call use could be established. However, measurable differences in vocal behaviour between the seasons and the sexes indicate that calling is used in a reproductive context, similar to other nocturnal and diurnal primates.
-
spatiotemporal distribution of individuals as an indicator for the social system of lepiLemur sahamalaza
American Journal of Primatology, 2019Co-Authors: Isabella Mandl, Marc W Holderied, Christoph SchwitzerAbstract:Primate social systems are highly diverse, complicating the classification of particularly elusive species that are difficult to observe. The spatial distribution of individuals over time is a critica lindicator for the social organization and long-term studies are important to establish patterns of social interactions. In recent years, species of the cryptic, nocturnal Sportive Lemurs of the genus LepiLemur were found to live in pairs in which a single male and a single female share and defend a mutual home range. The present study aimed to forward research into this underrepresented genus by determining the social organization and structure of the Sahamalaza Sportive Lemur, L. sahamalaza. We collected 773.15 hr of behavioral and GPS data during a period of 10 months (between 2015 and 2016) on 14 individuals: eight females and six males. There was no evidence of pair-specific home range use as intra- and intersexual home range overlap was high. No pattern of social interactions between focal individuals could be distinguished despite high range overlap. Individuals met and interacted infrequently, resulting in an interaction rate of 0.32 interactions/hr. Sleeping associations between adult individuals were never observed. While both sexes had access to multiple potential mating partners, range sizes or ranging distances did not increase in mating periods. Overall, the social system of Sahamalaza Sportive Lemurs exhibits aspects of a solitary social organization and structure with potential for the polygamous mating system. These findings underline the importance of detailed social ecology studies that can provide the basis for understanding potential environmental influences on social system variability of closely related species.
-
use of space and home range characteristics of lepiLemur mittermeieri an endangered Sportive Lemur endemic to the ampasindava peninsula north west madagascar
American Journal of Primatology, 2019Co-Authors: Hajanirina Rakotondrainibe, Leslie Wilmet, Christoph Schwitzer, Pierre Devillers, Roseline Beudelsjamar, Cedric VermeulenAbstract: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.
-
The Effects of Climate Seasonality on Behavior and Sleeping Site Choice in Sahamalaza Sportive Lemurs, LepiLemur sahamalaza
International Journal of Primatology, 2018Co-Authors: Isabella Mandl, Marc Holderied, Christoph SchwitzerAbstract:Temperature, rainfall, and resource availability may vary greatly within a single year in primate habitats. Many primate species show behavioral and physiological adaptations to this environmental seasonality, including changes to their diets and activity. Sahamalaza Sportive Lemurs ( LepiLemur sahamalaza ) inhabit the northwest of Madagascar and have been studied only during the dry, colder period of the year. We investigated potential effects of climate seasonality on this species by collecting behavioral data between October 2015 and August 2016, encompassing both the warmer wet and the colder dry seasons. We collected 773.15 hours of behavioral data on 14 individual Sportive Lemurs to investigate year-round activity budgets, ranging behavior, and sleeping site locations. Additionally we recorded temperature and rainfall data at our study site to describe the environmental conditions during the study period. The study individuals significantly decreased their time spent traveling and increased their time spent resting in the dry season compared to the wet season. Although home range size and path lengths did not differ over the study period, sleeping locations were significantly different between seasons as the Lemurs focused on more confined areas in colder periods. Overall, the results indicate that Sahamalaza Sportive Lemur behavior varies with season, in line with reports for other primates.
-
home range size and social organization of the sahamalaza Sportive Lemur lepiLemur sahamalazensis
Primate Conservation, 2015Co-Authors: Melanie Seiler, Marc W Holderied, Christoph SchwitzerAbstract:Abstract: Knowledge of a species' social organization and spatial needs is essential to set up effective conservation measures. To date, there have been published studies on the home range size and social organization of only three of the 26 Sportive Lemur species currently recognized; there is no information available for the remaining 23. We studied home range size and social organization for the first time in the Critically Endangered Sahamalaza Sportive Lemur (LepiLemur sahamalazensis) by following eight radio-tagged individuals for 666 hours. Observations were made at night, recording interactions between them and the distances they travelled. Home ranges covered 0.38 ha and there was no overlap between adult individuals; nightly ranges were about 0.1 ha. Almost no social interactions were seen, and the very few observed sociopositive interactions took place between mother and kin, as suggested by size differences and diurnal observations. The small number of individuals observed makes conclusive inf...
Solofonirina Rasoloharijaona - One of the best experts on this subject based on the ideXlab platform.
-
Are sleeping site ecology and season linked to intestinal helminth prevalence and diversity in two sympatric, nocturnal and arboreal primate hosts (LepiLemur edwardsi and Avahi occidentalis)?
BMC Ecology, 2018Co-Authors: May Hokan, Bertrand Andriatsitohaina, Ute Radespiel, Elke Zimmermann, Solofonirina RasoloharijaonaAbstract:Background Various factors, such as climate, body size and sociality are often linked to parasitism. This constrains the identification of other determinants driving parasite infections. Here, we investigate for the first time intestinal parasites in two sympatric arboreal primate species, which share similar activity patterns, feeding ecology, body size and sociality, and cope with the same climate conditions, but differ in sleeping site ecology: the Milne-Edward’s Sportive Lemur ( LepiLemur edwardsi ) and the Western woolly Lemur ( Avahi occidentalis ). Comparison of these two species aimed to test whether differences in sleeping sites are related to differences in parasite infection patterns. Additionally, gender and seasonal factors were taken into account. Animals were radio-collared to record their sleeping site dynamics and to collect fecal samples to assess intestinal parasitism during both the dry and the rainy season. Results Only low parasite diversity was detected, which is attributable to the strict arboreal lifestyle of these Lemurs, limiting their contact with infective parasite stages. L. edwardsi , which sleeps in tree holes and repeatedly uses the same sleeping site, excreted eggs of strongyle and oxyurid nematodes, whereby strongyles always occurred in coinfection with oxyurids. In contrast, A. occidentalis , which sleeps on open branches and frequently changes sleeping sites, only excreted eggs of strongyle nematodes. This difference can be attributed to a potential favorable environment presented by tree holes for infective stages, facilitating parasitic transmission. Additionally, Strongylida in A. occidentalis were only observed in the rainy season, suggesting an arrested development during the dry season in the nematodes’ life cycle. Males and females of both Lemur species showed the same frequency of parasitism. No differences in body mass of infected and non-infected individuals were observed, indicating that the animals’ body condition remains unaffected by the detected gastrointestinal parasites. Conclusions The comparison of two primate hosts with a very similar lifestyle suggests an influence of the sleeping site ecology on intestinal parasites. In A. occidentalis there was a clear seasonal difference in strongyle egg excretion. These results improve our understanding of the parasite ecology in these endangered primate species, which may be critical in the light of species conservation.
-
Are sleeping site ecology and season linked to intestinal helminth prevalence and diversity in two sympatric, nocturnal and arboreal primate hosts (LepiLemur edwardsi and Avahi occidentalis)?
BMC Ecology, 2018Co-Authors: May Hokan, Bertrand Andriatsitohaina, Solofonirina Rasoloharijaona, Ute Radespiel, Elke Zimmermann, Christina StrubeAbstract:Background Various factors, such as climate, body size and sociality are often linked to parasitism. This constrains the identification of other determinants driving parasite infections. Here, we investigate for the first time intestinal parasites in two sympatric arboreal primate species, which share similar activity patterns, feeding ecology, body size and sociality, and cope with the same climate conditions, but differ in sleeping site ecology: the Milne-Edward’s Sportive Lemur ( LepiLemur edwardsi ) and the Western woolly Lemur ( Avahi occidentalis ). Comparison of these two species aimed to test whether differences in sleeping sites are related to differences in parasite infection patterns. Additionally, gender and seasonal factors were taken into account. Animals were radio-collared to record their sleeping site dynamics and to collect fecal samples to assess intestinal parasitism during both the dry and the rainy season. Results Only low parasite diversity was detected, which is attributable to the strict arboreal lifestyle of these Lemurs, limiting their contact with infective parasite stages. L. edwardsi , which sleeps in tree holes and repeatedly uses the same sleeping site, excreted eggs of strongyle and oxyurid nematodes, whereby strongyles always occurred in coinfection with oxyurids. In contrast, A. occidentalis , which sleeps on open branches and frequently changes sleeping sites, only excreted eggs of strongyle nematodes. This difference can be attributed to a potential favorable environment presented by tree holes for infective stages, facilitating parasitic transmission. Additionally, Strongylida in A. occidentalis were only observed in the rainy season, suggesting an arrested development during the dry season in the nematodes’ life cycle. Males and females of both Lemur species showed the same frequency of parasitism. No differences in body mass of infected and non-infected individuals were observed, indicating that the animals’ body condition remains unaffected by the detected gastrointestinal parasites. Conclusions The comparison of two primate hosts with a very similar lifestyle suggests an influence of the sleeping site ecology on intestinal parasites. In A. occidentalis there was a clear seasonal difference in strongyle egg excretion. These results improve our understanding of the parasite ecology in these endangered primate species, which may be critical in the light of species conservation.
-
sleeping site ecology in a rain forest dwelling nocturnal Lemur lepiLemur mustelinus implications for sociality and conservation
American Journal of Primatology, 2008Co-Authors: Blanchard Randrianambinina, Solofonirina Rasoloharijaona, Elke ZimmermannAbstract:Suitable sleeping sites as potentially restricted resources are suggested to shape sociality in primates. We investigated sleeping site ecology of a rain-forest dwelling Sportive Lemur in eastern Madagascar for the first time. Using radiotelemetry, we characterized the type, quality and usage of sleeping sites as well as social sleeping habits of 11 focal individuals of the weasel Sportive Lemur (LepiLemur mustelinus) during the dry and the onset of the rainy season. Morphometric measurements provided additional information. The sexes showed an unusual sexual dimorphism for primates. Males and females did not differ in body length, but females surpassed males in body mass suggesting female dominance. Both sexes used dense vegetation and holes in hollow trees high above the ground as shelters for sleeping during the day. No sex difference in the quality of tree holes was found, but focal individuals used tree holes more often than open sleeping sites in dense vegetation. Both sexes showed high sleeping site fidelity limited to two to six different sites that they used primarily solitarily. The results imply that suitable sleeping sites are limited and survival of this species will strongly depend on the availability of mature rain forests with suitable hollow trees. Furthermore, these findings provide evidence of a solitary sleeping and ranging system in this rain-forest dwelling Sportive Lemur with suitable sleeping sites as defendable resources.
-
Unexpected species diversity of Malagasy primates (LepiLemur spp.) in the same biogeographical zone: a morphological and molecular approach with the description of two new species
BMC Evolutionary Biology, 2007Co-Authors: Mathias Craul, Blanchard Randrianambinina, Solofonirina Rasoloharijaona, Elke Zimmermann, Ute RadespielAbstract:Background The Lemurs of Madagascar provide an excellent mammalian radiation to explore mechanisms and processes favouring species diversity and evolution. Species diversity, in particular of nocturnal species, increased considerably during the last decade. However, the factors contributing to this high diversity are not well understood. We tested predictions derived from two existing biogeographic models by exploring the genetic and morphological divergence among populations of a widely distributed Lemur genus, the Sportive Lemur ( LepiLemur ssp.) along a 560 km long transect from western to northern Madagascar. Results By using the phylogenetic analyses of mtDNA sequence data, molecular diagnostic sites and phenotypic morphometric traits, we uncovered two previously undetected species whose distributions contradict the two existing biogeographic models. Brief species descriptions are provided and a new biogeographic model is proposed (the ”large river model“). Conclusion According to the ”large river model“, large rivers in north and northwestern Madagascar acted as geographical barriers for gene flow and facilitated speciation events on a much smaller spatial scale than previously thought. Thereby, this study does not only show that species diversity in nocturnal Malagasy primates is continuously underestimated but aims to emphasize the need for conservation actions if those species with small ranges shall not face extinction in the near future.
-
Unexpected species diversity of Malagasy primates (LepiLemur spp.) in the same biogeographical zone: a morphological and molecular approach with the description of two new species.
BMC evolutionary biology, 2007Co-Authors: Mathias Craul, Blanchard Randrianambinina, Solofonirina Rasoloharijaona, Elke Zimmermann, Ute RadespielAbstract:The Lemurs of Madagascar provide an excellent mammalian radiation to explore mechanisms and processes favouring species diversity and evolution. Species diversity, in particular of nocturnal species, increased considerably during the last decade. However, the factors contributing to this high diversity are not well understood. We tested predictions derived from two existing biogeographic models by exploring the genetic and morphological divergence among populations of a widely distributed Lemur genus, the Sportive Lemur (LepiLemur ssp.) along a 560 km long transect from western to northern Madagascar. By using the phylogenetic analyses of mtDNA sequence data, molecular diagnostic sites and phenotypic morphometric traits, we uncovered two previously undetected species whose distributions contradict the two existing biogeographic models. Brief species descriptions are provided and a new biogeographic model is proposed (the ”large river model“). According to the ”large river model“, large rivers in north and northwestern Madagascar acted as geographical barriers for gene flow and facilitated speciation events on a much smaller spatial scale than previously thought. Thereby, this study does not only show that species diversity in nocturnal Malagasy primates is continuously underestimated but aims to emphasize the need for conservation actions if those species with small ranges shall not face extinction in the near future.
Marc W Holderied - One of the best experts on this subject based on the ideXlab platform.
-
sahamalaza Sportive Lemur lepiLemur sahamalaza vocal communication call use context and gradation
Folia Primatologica, 2019Co-Authors: Isabella Mandl, Christoph Schwitzer, Marc W HolderiedAbstract:Stereotypical vocalisations can facilitate long-distance communication in dense and, thus, sound-degrading forest habitats. Despite this, primate vocal repertoires often also include gradations between different call types that are used in social interactions. Because many nocturnal primates show a solitary social structure, it has been difficult to assess the role vocalisations play in mediating their social encounters. Here we aim to expand on the call types of Sahamalaza Sportive Lemurs, LepiLemur sahamalaza, as well as investigate their variability and use in social contexts. Through long-term behavioural observations with concurrent recording of vocalisations of known and unknown individuals between 2015 and 2016, we described three previously unrecorded calls and expanded the vocal repertoire to 12 different call types that were used in both targeted social and broadcast solitary contexts. Linear discriminant function and cluster analysis supported initial observations that vocalisations within call types were variable and that at least two call types can be classified as "graded," contrary to expectations. Despite variations in call-context connections, no clear patterns of call use could be established. However, measurable differences in vocal behaviour between the seasons and the sexes indicate that calling is used in a reproductive context, similar to other nocturnal and diurnal primates.
-
spatiotemporal distribution of individuals as an indicator for the social system of lepiLemur sahamalaza
American Journal of Primatology, 2019Co-Authors: Isabella Mandl, Marc W Holderied, Christoph SchwitzerAbstract:Primate social systems are highly diverse, complicating the classification of particularly elusive species that are difficult to observe. The spatial distribution of individuals over time is a critica lindicator for the social organization and long-term studies are important to establish patterns of social interactions. In recent years, species of the cryptic, nocturnal Sportive Lemurs of the genus LepiLemur were found to live in pairs in which a single male and a single female share and defend a mutual home range. The present study aimed to forward research into this underrepresented genus by determining the social organization and structure of the Sahamalaza Sportive Lemur, L. sahamalaza. We collected 773.15 hr of behavioral and GPS data during a period of 10 months (between 2015 and 2016) on 14 individuals: eight females and six males. There was no evidence of pair-specific home range use as intra- and intersexual home range overlap was high. No pattern of social interactions between focal individuals could be distinguished despite high range overlap. Individuals met and interacted infrequently, resulting in an interaction rate of 0.32 interactions/hr. Sleeping associations between adult individuals were never observed. While both sexes had access to multiple potential mating partners, range sizes or ranging distances did not increase in mating periods. Overall, the social system of Sahamalaza Sportive Lemurs exhibits aspects of a solitary social organization and structure with potential for the polygamous mating system. These findings underline the importance of detailed social ecology studies that can provide the basis for understanding potential environmental influences on social system variability of closely related species.
-
home range size and social organization of the sahamalaza Sportive Lemur lepiLemur sahamalazensis
Primate Conservation, 2015Co-Authors: Melanie Seiler, Marc W Holderied, Christoph SchwitzerAbstract:Abstract: Knowledge of a species' social organization and spatial needs is essential to set up effective conservation measures. To date, there have been published studies on the home range size and social organization of only three of the 26 Sportive Lemur species currently recognized; there is no information available for the remaining 23. We studied home range size and social organization for the first time in the Critically Endangered Sahamalaza Sportive Lemur (LepiLemur sahamalazensis) by following eight radio-tagged individuals for 666 hours. Observations were made at night, recording interactions between them and the distances they travelled. Home ranges covered 0.38 ha and there was no overlap between adult individuals; nightly ranges were about 0.1 ha. Almost no social interactions were seen, and the very few observed sociopositive interactions took place between mother and kin, as suggested by size differences and diurnal observations. The small number of individuals observed makes conclusive inf...
-
call repertoire of the sahamalaza Sportive Lemur lepiLemur sahamalazensis
International Journal of Primatology, 2015Co-Authors: Melanie Seiler, Christoph Schwitzer, Marc W HolderiedAbstract:The acoustic structure of primate loud calls can be used as a powerful, inexpensive, and noninvasive tool for intra- and interspecific comparative analyses, reconstruction of phylogeny, and primate surveys. Despite the range of possibilities offered by acoustic analysis, only few studies so far have focused on quantitative descriptions of the acoustic structure of primate loud call repertoires. Here we aimed to assess the vocal repertoire of the solitary Sahamalaza Sportive Lemur, LepiLemur sahamalazensis, and to investigate potential communication functions. We recorded every Sportive Lemur vocalization we heard during 1000 h of nocturnal observations of eight collared individuals, as well as opportunistic searches in the Ankarafa Forest, Sahamalaza Peninsula in northwest Madagascar. In addition, we used playback experiments with four call types to clarify call function. We measured both temporal and spectral properties to describe calls quantitatively and used cross-validated discriminant function analysis to validate call types that we identified from a preliminary qualitative inspection of the spectrograms of 107 calls. We identified six distinct loud call types with the possibility of a seventh call type, with six loud call types similar to those of LepiLemur edwardsi and two loud call types similar to those of four other Sportive Lemur species. The described call types most likely function in mate advertisement, offspring care, and territorial defense. Future studies of loud calling of the Sahamalaza Sportive Lemur are needed to clarify if certain call types are sex specific and if loud calls could be used for recognition of individuals to enable noninvasive density measurements and species monitoring.
-
habitat selection and use in the critically endangered sahamalaza Sportive Lemur lepiLemur sahamalazensis in altered habitat
Endangered Species Research, 2014Co-Authors: Melanie Seiler, Marc W Holderied, Christoph SchwitzerAbstract:Habitat selection and use by primates is influenced by the trade-off between distri- bution of foraging resources and predation risk. So far, there are published studies on habitat use for 2 out of 26 Sportive Lemur species, but none document habitat selection. We studied habitat in home ranges as well as feeding preferences and nightly activity budgets in the Sahamalaza Sportive Lemur LepiLemur sahamalazensis. We describe the habitat structure of home ranges located in 4 forest fragments in Madagascar with varying habitat characteristics after following 8 radio-tagged individuals for a total of 666 h at night. With the limitation of small sample size, our results suggest that Sahamalaza Sportive Lemurs choose the locations of their home ranges on the basis of different habitat variables, with abundance of sleeping sites and feeding trees as well as tree density and canopy cover being the most important factors. The Sahamalaza Sportive Lemur is a highly folivorous generalist herbivore, feeding on at least 42 different tree species and prefer- ring the abundant species Clitoria lasciva, Mangifera indica, Garcinia pauciflora and Sorindeia madagascariensis. It has prolonged times of resting during its activity periods. Our results imply that despite its habitat selectivity, even the most degraded fragments on the Sahamalaza Penin- sula still adequately meet the species' habitat requirements. However, the small extent of the remaining forest and ongoing deforestation, forest degradation and poaching call the future sur- vival of this Critically Endangered species into question.
Ute Radespiel - One of the best experts on this subject based on the ideXlab platform.
-
the impact of anthropogenic disturbance on the behavior of milne edwards Sportive Lemurs lepiLemur edwardsi
Winter Meeting of the Primate Society of Great Britain 2019, 2019Co-Authors: J Muir, Ute Radespiel, Rindrahatsarana Ramanankirahina, P LeeAbstract:Effective conservation action requires more research on threatened primate species, particularly Lemurs. Madagascar has experienced extensive habitat disturbance, affecting species such as the endangered Milne Edwards Sportive Lemur (LepiLemur edwardsi), while its behaviour and responses to disturbance remain almost unknown. This study investigated if Lemur abundance is affected by anthropogenic disturbance and whether vocalisations are related to habitat, animal abundance or light levels. This study was conducted over the June-July of 2016 in Mariarano, Northwest Madagascar, using systematic nocturnal surveys to determine abundance, opportunistic focal observations to record behaviour, and all occurrences recording of vocalisation across three sites with varying distances from areas of disturbance (village). More disturbed areas had lower abundance and increased activity, suggesting a negative response to disturbance, which implies they may not benefit from edge effects acting on leaf production, contrary to evidence in other folivores. Vocal rate increased with higher abundance, supporting a territory defence motive for vocalisations. With increased moonlight, vocal rate decreased, suggesting a predator avoidance response to changes in moonlight. These results shed more light on how L.edwardsi reacts to disturbance, the functions of vocalisations, responses to variation in moonlight, and provides a basis for further study. This information could help with evaluations of how much pressure from disturbance could be tolerated and so how important conservation action must be.
-
Are sleeping site ecology and season linked to intestinal helminth prevalence and diversity in two sympatric, nocturnal and arboreal primate hosts (LepiLemur edwardsi and Avahi occidentalis)?
BMC Ecology, 2018Co-Authors: May Hokan, Bertrand Andriatsitohaina, Ute Radespiel, Elke Zimmermann, Solofonirina RasoloharijaonaAbstract:Background Various factors, such as climate, body size and sociality are often linked to parasitism. This constrains the identification of other determinants driving parasite infections. Here, we investigate for the first time intestinal parasites in two sympatric arboreal primate species, which share similar activity patterns, feeding ecology, body size and sociality, and cope with the same climate conditions, but differ in sleeping site ecology: the Milne-Edward’s Sportive Lemur ( LepiLemur edwardsi ) and the Western woolly Lemur ( Avahi occidentalis ). Comparison of these two species aimed to test whether differences in sleeping sites are related to differences in parasite infection patterns. Additionally, gender and seasonal factors were taken into account. Animals were radio-collared to record their sleeping site dynamics and to collect fecal samples to assess intestinal parasitism during both the dry and the rainy season. Results Only low parasite diversity was detected, which is attributable to the strict arboreal lifestyle of these Lemurs, limiting their contact with infective parasite stages. L. edwardsi , which sleeps in tree holes and repeatedly uses the same sleeping site, excreted eggs of strongyle and oxyurid nematodes, whereby strongyles always occurred in coinfection with oxyurids. In contrast, A. occidentalis , which sleeps on open branches and frequently changes sleeping sites, only excreted eggs of strongyle nematodes. This difference can be attributed to a potential favorable environment presented by tree holes for infective stages, facilitating parasitic transmission. Additionally, Strongylida in A. occidentalis were only observed in the rainy season, suggesting an arrested development during the dry season in the nematodes’ life cycle. Males and females of both Lemur species showed the same frequency of parasitism. No differences in body mass of infected and non-infected individuals were observed, indicating that the animals’ body condition remains unaffected by the detected gastrointestinal parasites. Conclusions The comparison of two primate hosts with a very similar lifestyle suggests an influence of the sleeping site ecology on intestinal parasites. In A. occidentalis there was a clear seasonal difference in strongyle egg excretion. These results improve our understanding of the parasite ecology in these endangered primate species, which may be critical in the light of species conservation.
-
Are sleeping site ecology and season linked to intestinal helminth prevalence and diversity in two sympatric, nocturnal and arboreal primate hosts (LepiLemur edwardsi and Avahi occidentalis)?
BMC Ecology, 2018Co-Authors: May Hokan, Bertrand Andriatsitohaina, Solofonirina Rasoloharijaona, Ute Radespiel, Elke Zimmermann, Christina StrubeAbstract:Background Various factors, such as climate, body size and sociality are often linked to parasitism. This constrains the identification of other determinants driving parasite infections. Here, we investigate for the first time intestinal parasites in two sympatric arboreal primate species, which share similar activity patterns, feeding ecology, body size and sociality, and cope with the same climate conditions, but differ in sleeping site ecology: the Milne-Edward’s Sportive Lemur ( LepiLemur edwardsi ) and the Western woolly Lemur ( Avahi occidentalis ). Comparison of these two species aimed to test whether differences in sleeping sites are related to differences in parasite infection patterns. Additionally, gender and seasonal factors were taken into account. Animals were radio-collared to record their sleeping site dynamics and to collect fecal samples to assess intestinal parasitism during both the dry and the rainy season. Results Only low parasite diversity was detected, which is attributable to the strict arboreal lifestyle of these Lemurs, limiting their contact with infective parasite stages. L. edwardsi , which sleeps in tree holes and repeatedly uses the same sleeping site, excreted eggs of strongyle and oxyurid nematodes, whereby strongyles always occurred in coinfection with oxyurids. In contrast, A. occidentalis , which sleeps on open branches and frequently changes sleeping sites, only excreted eggs of strongyle nematodes. This difference can be attributed to a potential favorable environment presented by tree holes for infective stages, facilitating parasitic transmission. Additionally, Strongylida in A. occidentalis were only observed in the rainy season, suggesting an arrested development during the dry season in the nematodes’ life cycle. Males and females of both Lemur species showed the same frequency of parasitism. No differences in body mass of infected and non-infected individuals were observed, indicating that the animals’ body condition remains unaffected by the detected gastrointestinal parasites. Conclusions The comparison of two primate hosts with a very similar lifestyle suggests an influence of the sleeping site ecology on intestinal parasites. In A. occidentalis there was a clear seasonal difference in strongyle egg excretion. These results improve our understanding of the parasite ecology in these endangered primate species, which may be critical in the light of species conservation.
-
Sleeping site ecology, but not sex, affect ecto- and hemoparasite risk, in sympatric, arboreal primates (Avahi occidentalis and LepiLemur edwardsi)
Frontiers in Zoology, 2017Co-Authors: May Hokan, Ute Radespiel, Christina Strube, Elke ZimmermannAbstract:Background A central question in evolutionary parasitology is to what extent ecology impacts patterns of parasitism in wild host populations. In this study, we aim to disentangle factors influencing the risk of parasite exposure by exploring the impact of sleeping site ecology on infection with ectoparasites and vector-borne hemoparasites in two sympatric primates endemic to Madagascar. Both species live in the same dry deciduous forest of northwestern Madagascar and cope with the same climatic constraints, they are arboreal, nocturnal, cat-sized and pair-living but differ prominently in sleeping site ecology. The Western woolly Lemur ( Avahi occidentalis ) sleeps on open branches and frequently changes sleeping sites, whereas the Milne-Edward’s Sportive Lemur ( LepiLemur edwardsi ) uses tree holes, displaying strong sleeping site fidelity. Sleeping in tree holes should confer protection from mosquito-borne hemoparasites, but should enhance the risk for ectoparasite infestation with mites and nest-adapted ticks. Sex may affect parasite risk in both species comparably, with males bearing a higher risk than females due to an immunosuppressive effect of higher testosterone levels in males or to sex-specific behavior. To explore these hypotheses, ectoparasites and blood samples were collected from 22 individuals of A. occidentalis and 26 individuals of L. edwardsi during the dry and rainy season. Results L. edwardsi, but not A. occidentalis , harbored ectoparasites, namely ticks ( Haemaphysalis Lemuris [Ixodidae], Ornithodoros sp. [Argasidae]) and mites ( Aetholaelaps trilyssa , [Laelapidae]), suggesting that sleeping in tree holes promotes infestation with ectoparasites. Interestingly, ectoparasites were found solely in the hot, rainy season with a prevalence of 75% ( N = 16 animals). Blood smears were screened for the presence and infection intensity of hemoparasites. Microfilariae were detected in both species. Morphological characteristics suggested that each Lemur species harbored two different filarial species. Prevalence of microfilarial infection was significantly lower in L. edwardsi than in A. occidentalis. No significant difference in infection intensity between the two host species, and no effect of season, daytime of sampling or sex on prevalence or infection intensity was found. In neither host species, parasite infection showed an influence on body weight as an indicator for body condition. Conclusions Our findings support that sleeping site ecology affects ectoparasite infestation in nocturnal, arboreal mammalian hosts in the tropics, whereas there is no significant effect of host sex. The influence of sleeping site ecology to vector-borne hemoparasite risk is less pronounced. The observed parasite infections did not affect body condition and thus may be of minor importance for shaping reproductive fitness. Findings provide first evidence for the specific relevance of sleeping site ecology on parasitism in arboreal and social mammals. Further, our results increase the sparse knowledge on ecological drivers of primate host-parasite interactions and transmission pathways in natural tropical environments.
-
sleeping site ecology but not sex affect ecto and hemoparasite risk in sympatric arboreal primates avahi occidentalis and lepiLemur edwardsi
Frontiers in Zoology, 2017Co-Authors: May Hokan, Ute Radespiel, Christina Strube, Elke ZimmermannAbstract:A central question in evolutionary parasitology is to what extent ecology impacts patterns of parasitism in wild host populations. In this study, we aim to disentangle factors influencing the risk of parasite exposure by exploring the impact of sleeping site ecology on infection with ectoparasites and vector-borne hemoparasites in two sympatric primates endemic to Madagascar. Both species live in the same dry deciduous forest of northwestern Madagascar and cope with the same climatic constraints, they are arboreal, nocturnal, cat-sized and pair-living but differ prominently in sleeping site ecology. The Western woolly Lemur (Avahi occidentalis) sleeps on open branches and frequently changes sleeping sites, whereas the Milne-Edward’s Sportive Lemur (LepiLemur edwardsi) uses tree holes, displaying strong sleeping site fidelity. Sleeping in tree holes should confer protection from mosquito-borne hemoparasites, but should enhance the risk for ectoparasite infestation with mites and nest-adapted ticks. Sex may affect parasite risk in both species comparably, with males bearing a higher risk than females due to an immunosuppressive effect of higher testosterone levels in males or to sex-specific behavior. To explore these hypotheses, ectoparasites and blood samples were collected from 22 individuals of A. occidentalis and 26 individuals of L. edwardsi during the dry and rainy season. L. edwardsi, but not A. occidentalis, harbored ectoparasites, namely ticks (Haemaphysalis Lemuris [Ixodidae], Ornithodoros sp. [Argasidae]) and mites (Aetholaelaps trilyssa, [Laelapidae]), suggesting that sleeping in tree holes promotes infestation with ectoparasites. Interestingly, ectoparasites were found solely in the hot, rainy season with a prevalence of 75% (N = 16 animals). Blood smears were screened for the presence and infection intensity of hemoparasites. Microfilariae were detected in both species. Morphological characteristics suggested that each Lemur species harbored two different filarial species. Prevalence of microfilarial infection was significantly lower in L. edwardsi than in A. occidentalis. No significant difference in infection intensity between the two host species, and no effect of season, daytime of sampling or sex on prevalence or infection intensity was found. In neither host species, parasite infection showed an influence on body weight as an indicator for body condition. Our findings support that sleeping site ecology affects ectoparasite infestation in nocturnal, arboreal mammalian hosts in the tropics, whereas there is no significant effect of host sex. The influence of sleeping site ecology to vector-borne hemoparasite risk is less pronounced. The observed parasite infections did not affect body condition and thus may be of minor importance for shaping reproductive fitness. Findings provide first evidence for the specific relevance of sleeping site ecology on parasitism in arboreal and social mammals. Further, our results increase the sparse knowledge on ecological drivers of primate host-parasite interactions and transmission pathways in natural tropical environments.