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Peter M. Kappeler - One of the best experts on this subject based on the ideXlab platform.
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The role of facial pattern variation for species recognition in red-fronted lemurs (Eulemur rufifrons).
BMC Evolutionary Biology, 2018Co-Authors: Hanitriniaina Rakotonirina, Peter M. Kappeler, Claudia FichtelAbstract:Species recognition, i.e., the ability to distinguish conspecifics from heterospecifics, plays an essential role in reproduction. The role of facial cues for species recognition has been investigated in several non-human primate species except for lemurs. We therefore investigated the role of facial cues for species recognition in wild red-fronted lemurs (Eulemur rufifrons) at Kirindy Forest. We presented adult red-fronted lemurs pictures of male faces from five species including red-fronted lemurs, three closely related species, white-fronted lemurs (E. albifrons), brown lemurs (E. fulvus), rufous brown lemurs (E. rufus), and genetically more distant red-bellied lemurs (E. rubriventer), occurring in allopatry with the study population. We predicted that red-fronted lemurs respond stronger to conspecific than to heterospecific pictures and that females show stronger responses than males. In addition, if genetic drift has played a role in the evolution of facial color patterns in the members of this genus, we predicted that responses of red-fronted lemurs correlate negatively with the genetic distance to the different species stimuli. Red-fronted lemurs looked significantly longer at pictures of their own species than at those of heterospecifics. Females spent less time looking at pictures of white-fronted, brown and red-bellied lemurs than males did, but not to pictures of red-bellied lemurs and a control stimulus. Individuals also exhibited sniffing behavior while looking at visual stimuli, and the time spent sniffing was significantly longer for pictures of conspecifics compared to those of heterospecifics. Moreover, the time spent looking and sniffing towards the pictures correlated negatively with the genetic distance between their own species and the species presented as stimulus. We conclude that red-fronted lemurs have the ability for species recognition using visual facial cues, which may allow them to avoid costly interbreeding. If so, sexual selection might have influenced the evolution of facial patterns in Eulemurs. Since responses also correlated with genetic distance, our findings suggest a potential role of genetic drift as well as sexual selection in influencing the evolution of facial variation in Eulemurs. Because study subjects looked and sniffed towards the presented pictures, red-fronted lemurs might have the ability for multi-modal species recognition.
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The role of facial pattern variation for species recognition in red-fronted lemurs (Eulemur rufifrons)
BMC, 2018Co-Authors: Hanitriniaina Rakotonirina, Peter M. Kappeler, Claudia FichtelAbstract:Abstract Background Species recognition, i.e., the ability to distinguish conspecifics from heterospecifics, plays an essential role in reproduction. The role of facial cues for species recognition has been investigated in several non-human primate species except for lemurs. We therefore investigated the role of facial cues for species recognition in wild red-fronted lemurs (Eulemur rufifrons) at Kirindy Forest. We presented adult red-fronted lemurs pictures of male faces from five species including red-fronted lemurs, three closely related species, white-fronted lemurs (E. albifrons), brown lemurs (E. fulvus), rufous brown lemurs (E. rufus), and genetically more distant red-bellied lemurs (E. rubriventer), occurring in allopatry with the study population. We predicted that red-fronted lemurs respond stronger to conspecific than to heterospecific pictures and that females show stronger responses than males. In addition, if genetic drift has played a role in the evolution of facial color patterns in the members of this genus, we predicted that responses of red-fronted lemurs correlate negatively with the genetic distance to the different species stimuli. Results Red-fronted lemurs looked significantly longer at pictures of their own species than at those of heterospecifics. Females spent less time looking at pictures of white-fronted, brown and red-bellied lemurs than males did, but not to pictures of red-bellied lemurs and a control stimulus. Individuals also exhibited sniffing behavior while looking at visual stimuli, and the time spent sniffing was significantly longer for pictures of conspecifics compared to those of heterospecifics. Moreover, the time spent looking and sniffing towards the pictures correlated negatively with the genetic distance between their own species and the species presented as stimulus. Conclusions We conclude that red-fronted lemurs have the ability for species recognition using visual facial cues, which may allow them to avoid costly interbreeding. If so, sexual selection might have influenced the evolution of facial patterns in Eulemurs. Since responses also correlated with genetic distance, our findings suggest a potential role of genetic drift as well as sexual selection in influencing the evolution of facial variation in Eulemurs. Because study subjects looked and sniffed towards the presented pictures, red-fronted lemurs might have the ability for multi-modal species recognition
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the role of acoustic signals for species recognition in redfronted lemurs Eulemur rufifrons
BMC Evolutionary Biology, 2016Co-Authors: Hanitriniaina Rakotonirina, Peter M. Kappeler, Claudia FichtelAbstract:Signals are essential for communication and play a fundamental role in the evolution and diversification of species. Olfactory, visual and acoustic species-specific signals have been shown to function for species recognition in non-human primates, but the relative contributions of selection for species recognition driven by sexual selection, natural selection, or genetic drift for the diversification of these signals remain largely unexplored. This study investigates the importance of acoustic signals for species recognition in redfronted lemurs (Eulemur rufifrons). We conducted playback experiments in both major populations of this species separated by several hundred kilometers: Kirindy Forest in the west and Ranomafana National Park in the east of Madagascar. The playback stimuli were composed of species-specific loud calls of E. rufifrons, three closely related species (E. albifrons, E. fulvus and E. rufus) and one genetically more distant species (E. rubriventer) that occurs in sympatry with eastern redfronted lemurs. We tested the ability of redfronted lemurs to discriminate conspecific from heterospecific loud calls by measuring the time spent looking towards the speaker after presentation of each loud call. We also tested the difference between female and male responses because loud calls may play a role in mate choice and the avoidance of heterospecific mating. Redfronted lemurs in Kirindy Forest did not discriminate their own loud calls from those of E. albifrons, E. fulvus and E. rufus, but they discriminated loud calls of E. rubriventer from their own. The Ranomafana population was tested only with three playback stimuli (E. rufifrons, E. albifrons, E. rubriventer) and did not discriminate between their own loud calls and those of E. albifrons and E. rubriventer. The response of females and males to playbacks did not differ in both populations. However, subjects in Ranomafana National Park responded more strongly to playback stimuli from E. rubriventer than subjects in Kirindy Forest. We conclude that in both populations individuals were not able to discriminate between loud calls of closely related species living in allopatry and that responses to more distantly related congeners are likely to be modulated by experience. Subjects in Ranomafana paid more attention to loud calls of syntopic E. rubriventer in comparison to the Kirindy subjects, suggesting that experience is important in facilitating discrimination. Because acoustic and genetic distances among Eulemurs are correlated, diversification in their acoustic signals might be the result of genetic drift.
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Kappeler_Fichtel
2016Co-Authors: Peter M. Kappeler, Claudia FichtelAbstract:The file contains demographic data on Eulemur rufifrons collected in Kirindy forest, Madagascar
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The Evolution of Eulemur Social Organization
International Journal of Primatology, 2015Co-Authors: Peter M. Kappeler, Claudia FichtelAbstract:Recent comparative studies on the evolution of mammalian sociality came to opposite conclusions regarding the direction and drivers of evolutionary transitions in social organization, particularly concerning the evolution of pair-living among primates. Because the genus Eulemur is one of the few exceptional primate genera that contain both group- and pair-living species, Eulemurs offer a rare opportunity to illuminate the processes driving social diversity among species with very similar life histories and ecologies. The aims of our study were therefore 1) to reconstruct the evolution of social organization in Eulemurs with new demographic and phylogenetic data and 2) to evaluate several hypotheses about the evolution of pair-living with data from our long-term study of Eulemur rufifrons and published data on other Eulemurs. Our review of published data confirmed that E. mongoz and E. rubriventer are pair-living, whereas the 10 other species of Eulemur live in groups with multiple adult males and females. Furthermore, pair-living evolved at least once among Eulemurs from group-living ancestors. The available comparative evidence indicated that this evolutionary transition was probably not driven by male infanticide, social instability, or singular ecological factors. Instead, we propose that female competition has favored small female group size and that this effect may have been exacerbated by interspecific competition with sympatric congeners in the ancestors of the pair-living species. In conclusion, we confirmed that the evolution of pair-living from group-living ancestors among true lemurs is exceptional, but not unique, among mammals, and that commonly invoked hypotheses for the evolution of pair-living do not appear to be supported for this genus.
Claudia Fichtel - One of the best experts on this subject based on the ideXlab platform.
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The role of facial pattern variation for species recognition in red-fronted lemurs (Eulemur rufifrons).
BMC Evolutionary Biology, 2018Co-Authors: Hanitriniaina Rakotonirina, Peter M. Kappeler, Claudia FichtelAbstract:Species recognition, i.e., the ability to distinguish conspecifics from heterospecifics, plays an essential role in reproduction. The role of facial cues for species recognition has been investigated in several non-human primate species except for lemurs. We therefore investigated the role of facial cues for species recognition in wild red-fronted lemurs (Eulemur rufifrons) at Kirindy Forest. We presented adult red-fronted lemurs pictures of male faces from five species including red-fronted lemurs, three closely related species, white-fronted lemurs (E. albifrons), brown lemurs (E. fulvus), rufous brown lemurs (E. rufus), and genetically more distant red-bellied lemurs (E. rubriventer), occurring in allopatry with the study population. We predicted that red-fronted lemurs respond stronger to conspecific than to heterospecific pictures and that females show stronger responses than males. In addition, if genetic drift has played a role in the evolution of facial color patterns in the members of this genus, we predicted that responses of red-fronted lemurs correlate negatively with the genetic distance to the different species stimuli. Red-fronted lemurs looked significantly longer at pictures of their own species than at those of heterospecifics. Females spent less time looking at pictures of white-fronted, brown and red-bellied lemurs than males did, but not to pictures of red-bellied lemurs and a control stimulus. Individuals also exhibited sniffing behavior while looking at visual stimuli, and the time spent sniffing was significantly longer for pictures of conspecifics compared to those of heterospecifics. Moreover, the time spent looking and sniffing towards the pictures correlated negatively with the genetic distance between their own species and the species presented as stimulus. We conclude that red-fronted lemurs have the ability for species recognition using visual facial cues, which may allow them to avoid costly interbreeding. If so, sexual selection might have influenced the evolution of facial patterns in Eulemurs. Since responses also correlated with genetic distance, our findings suggest a potential role of genetic drift as well as sexual selection in influencing the evolution of facial variation in Eulemurs. Because study subjects looked and sniffed towards the presented pictures, red-fronted lemurs might have the ability for multi-modal species recognition.
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The role of facial pattern variation for species recognition in red-fronted lemurs (Eulemur rufifrons)
BMC, 2018Co-Authors: Hanitriniaina Rakotonirina, Peter M. Kappeler, Claudia FichtelAbstract:Abstract Background Species recognition, i.e., the ability to distinguish conspecifics from heterospecifics, plays an essential role in reproduction. The role of facial cues for species recognition has been investigated in several non-human primate species except for lemurs. We therefore investigated the role of facial cues for species recognition in wild red-fronted lemurs (Eulemur rufifrons) at Kirindy Forest. We presented adult red-fronted lemurs pictures of male faces from five species including red-fronted lemurs, three closely related species, white-fronted lemurs (E. albifrons), brown lemurs (E. fulvus), rufous brown lemurs (E. rufus), and genetically more distant red-bellied lemurs (E. rubriventer), occurring in allopatry with the study population. We predicted that red-fronted lemurs respond stronger to conspecific than to heterospecific pictures and that females show stronger responses than males. In addition, if genetic drift has played a role in the evolution of facial color patterns in the members of this genus, we predicted that responses of red-fronted lemurs correlate negatively with the genetic distance to the different species stimuli. Results Red-fronted lemurs looked significantly longer at pictures of their own species than at those of heterospecifics. Females spent less time looking at pictures of white-fronted, brown and red-bellied lemurs than males did, but not to pictures of red-bellied lemurs and a control stimulus. Individuals also exhibited sniffing behavior while looking at visual stimuli, and the time spent sniffing was significantly longer for pictures of conspecifics compared to those of heterospecifics. Moreover, the time spent looking and sniffing towards the pictures correlated negatively with the genetic distance between their own species and the species presented as stimulus. Conclusions We conclude that red-fronted lemurs have the ability for species recognition using visual facial cues, which may allow them to avoid costly interbreeding. If so, sexual selection might have influenced the evolution of facial patterns in Eulemurs. Since responses also correlated with genetic distance, our findings suggest a potential role of genetic drift as well as sexual selection in influencing the evolution of facial variation in Eulemurs. Because study subjects looked and sniffed towards the presented pictures, red-fronted lemurs might have the ability for multi-modal species recognition
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the role of acoustic signals for species recognition in redfronted lemurs Eulemur rufifrons
BMC Evolutionary Biology, 2016Co-Authors: Hanitriniaina Rakotonirina, Peter M. Kappeler, Claudia FichtelAbstract:Signals are essential for communication and play a fundamental role in the evolution and diversification of species. Olfactory, visual and acoustic species-specific signals have been shown to function for species recognition in non-human primates, but the relative contributions of selection for species recognition driven by sexual selection, natural selection, or genetic drift for the diversification of these signals remain largely unexplored. This study investigates the importance of acoustic signals for species recognition in redfronted lemurs (Eulemur rufifrons). We conducted playback experiments in both major populations of this species separated by several hundred kilometers: Kirindy Forest in the west and Ranomafana National Park in the east of Madagascar. The playback stimuli were composed of species-specific loud calls of E. rufifrons, three closely related species (E. albifrons, E. fulvus and E. rufus) and one genetically more distant species (E. rubriventer) that occurs in sympatry with eastern redfronted lemurs. We tested the ability of redfronted lemurs to discriminate conspecific from heterospecific loud calls by measuring the time spent looking towards the speaker after presentation of each loud call. We also tested the difference between female and male responses because loud calls may play a role in mate choice and the avoidance of heterospecific mating. Redfronted lemurs in Kirindy Forest did not discriminate their own loud calls from those of E. albifrons, E. fulvus and E. rufus, but they discriminated loud calls of E. rubriventer from their own. The Ranomafana population was tested only with three playback stimuli (E. rufifrons, E. albifrons, E. rubriventer) and did not discriminate between their own loud calls and those of E. albifrons and E. rubriventer. The response of females and males to playbacks did not differ in both populations. However, subjects in Ranomafana National Park responded more strongly to playback stimuli from E. rubriventer than subjects in Kirindy Forest. We conclude that in both populations individuals were not able to discriminate between loud calls of closely related species living in allopatry and that responses to more distantly related congeners are likely to be modulated by experience. Subjects in Ranomafana paid more attention to loud calls of syntopic E. rubriventer in comparison to the Kirindy subjects, suggesting that experience is important in facilitating discrimination. Because acoustic and genetic distances among Eulemurs are correlated, diversification in their acoustic signals might be the result of genetic drift.
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Kappeler_Fichtel
2016Co-Authors: Peter M. Kappeler, Claudia FichtelAbstract:The file contains demographic data on Eulemur rufifrons collected in Kirindy forest, Madagascar
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The Evolution of Eulemur Social Organization
International Journal of Primatology, 2015Co-Authors: Peter M. Kappeler, Claudia FichtelAbstract:Recent comparative studies on the evolution of mammalian sociality came to opposite conclusions regarding the direction and drivers of evolutionary transitions in social organization, particularly concerning the evolution of pair-living among primates. Because the genus Eulemur is one of the few exceptional primate genera that contain both group- and pair-living species, Eulemurs offer a rare opportunity to illuminate the processes driving social diversity among species with very similar life histories and ecologies. The aims of our study were therefore 1) to reconstruct the evolution of social organization in Eulemurs with new demographic and phylogenetic data and 2) to evaluate several hypotheses about the evolution of pair-living with data from our long-term study of Eulemur rufifrons and published data on other Eulemurs. Our review of published data confirmed that E. mongoz and E. rubriventer are pair-living, whereas the 10 other species of Eulemur live in groups with multiple adult males and females. Furthermore, pair-living evolved at least once among Eulemurs from group-living ancestors. The available comparative evidence indicated that this evolutionary transition was probably not driven by male infanticide, social instability, or singular ecological factors. Instead, we propose that female competition has favored small female group size and that this effect may have been exacerbated by interspecific competition with sympatric congeners in the ancestors of the pair-living species. In conclusion, we confirmed that the evolution of pair-living from group-living ancestors among true lemurs is exceptional, but not unique, among mammals, and that commonly invoked hypotheses for the evolution of pair-living do not appear to be supported for this genus.
Deborah J. Overdorff - One of the best experts on this subject based on the ideXlab platform.
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population demography and social structure changes in Eulemur fulvus rufus from 1988 to 2003
American Journal of Physical Anthropology, 2008Co-Authors: Elizabeth M. Erhart, Deborah J. OverdorffAbstract:Eulemur fulvus rufus has been described as having stable multi-male/multi-female groups, a male- biased sex ratio, and female philopatry. However, in a 16- year study of this subspecies we documented a great deal of demographic change as several groups permanently fis- sioned, some groups disappeared, and new groups formed. We split the dataset into two periods, 1988 to 1993 and 1994 to 2003, which coincided with the first dis- appearance of a study group (in August 1994) and the first permanent group fission (in December 1994). The av- erage group size decreased by nearly half between the study periods (10.5-5.6), while the frequency of group membership changes increased (2.0-8.3 times/year), and the birth rate decreased (0.56-0.38). Females, as well as males, immigrated into study groups and transferred between groups, something that has been rarely seen in this subspecies. We also found a significant decline in the amount of fruit from the earliest part of the study to the latter part of the study. Study groups did not switch to other types of foods during periods of fruit shortage, but traveled outside of their home range areas more often over the study period. Finally, the density E. f. rufus decreased in the study area while the densities of their main food competitors, Varecia variegata and Eulemur rubriventer, increased. Although few primate populations are numerically stable over time, we suggest that female behavioral responses to decreases in fruit availability may have influenced some of the demographic changes we witnessed in this study. Am J Phys Anthropol
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Morphological variation in populations of Eulemur albocollaris and E. fulvus rufus
International Journal of Primatology, 2005Co-Authors: Steig E. Johnson, Deborah J. Overdorff, Adam D. Gordon, Rebecca M. Stumpf, Patricia C WrightAbstract:Sexual dimorphism in body size and canine weaponry is commonly associated with high levels of male-male competition. When group living species do not rely heavily on male-male competition for access to females, sperm competition may represent a viable alternative strategy. Unlike most haplorhine primates, lemurs are typically monomorphic in body weight and canine height. We assessed variability of body mass dimorphism and canine size dimorphism in brown lemurs using morphometric data from 3 populations in southeastern Madagascar: Eulemur fulvus rufus, E. albocollaris, and hybrids of the species. We found significant male-biased canine dimorphism in E. albocollaris in conjunction with body-size monomorphism. We observed similar patterns in the hybrids, but E. fulvus rufus exhibited significant female-biased size dimorphism and canine monomorphism. Testes volume was relatively high across study populations. Thus, sperm competition appears to be strong in brown lemurs. E. albocollaris males combine sperm competition with large canines, but not higher body mass, indicating a difference in sexual strategy from most lemurs. Patterns of body mass and canine size dimorphism are not uniform across brown lemur populations, indicating that future work on these populations can explicitly test models that predict relationships between size dimorphism and various types of competition.
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Adult Male Scent-Marking in Lemur catta and Eulemur fulvus rufus
International Journal of Primatology, 2002Co-Authors: Lisa Gould, Deborah J. OverdorffAbstract:Scent-marking and olfactory communication are used extensively by prosimians and can provide spatial and temporal records of group movement and behavior. We compare rates of male scent-marking in relation to reproductive seasons, male dominance rank, and habitat use in two related prosimians: Lemur catta and Eulemur fulvus rufus. We collected scent-marking data on adult male Lemur catta at Beza-Mahafaly Reserve (dry forest), and on Eulemur fulvus rufus at Ranomafana National Park (rainforest), Madagascar. In Lemur, rates of overall scent-marking differed significantly by reproductive season, with higher rates occurring in mating and lactation/migration periods, whereas in Eulemur, reproductive season did not appear to affect scent-marking rates. Dominance rank of male Lemur catta did not affect rates of scent-marking. Among male Eulemur fulvus, dominance relations were not apparent; however, 2 of the 5 focal males scent-marked somewhat more frequently during the mating season and also experienced greater mating success. In Lemur catta, higher rates of scent-marking in the mating season may relate to indirect reproductive competition during a period of high aggression, while such mating competition was not as marked in Eulemur fulvus. Furthermore, higher rates of marking in resident male Lemur catta during male migration may correlate with vigilance toward immigrating males. Greater overall scent-marking rates in ring-tailed lemurs may relate to extensive intergroup home range overlap and no area of exclusive use, whereas the red-fronted lemur groups tended to forage in areas of their home range where little-to-no intergroup overlap occurred.
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Census of brown lemurs (Eulemur fulvus sspp.) in southeastern Madagascar: methods-testing and conservation implications.
American Journal of Primatology, 1999Co-Authors: Steig E. Johnson, Deborah J. OverdorffAbstract:Four forest areas were censused in southeastern Madagascar from June-August 1995 to estimate local population densities and habitat conditions for two threatened subspecies of brown lemur (Eulemur fulvus collaris and Eulemur fulvus albocollaris). Survey transects varied in length (1-3.5 km) and in surveillance frequency (three to seven times). Additional test surveys were conducted at the Parc National de Ranomafana to compare transect methods in an area with known population densities of Eulemur fulvus. Based on these tests, we demonstrate that the use of existing trails for transects can result in a close estimate of local population size, although more replications and longer transects increase precision. Results from regional surveys indicate considerably smaller population densities for E. f. albocollaris (0.086 animals/ha). In contrast, E. f. collaris densities were relatively high (.107 animals/ha) at Midongy-Sud. We also noted variation among sites in the density of lianas, which was positively correlated with local population density (a possible indication of habitat degradation). More generally, habitats in E. f. albocollaris's range suffered from fragmentation, reduction in forest area, logging, and potentially greater hunting pressure. Based on these results, it is apparent that more immediate steps are necessary to preserve E. f. albocollaris populations and habitats.
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Female Coordination of Group Travel in Wild Propithecus and Eulemur
International Journal of Primatology, 1999Co-Authors: Elizabeth M. Erhart, Deborah J. OverdorffAbstract:Coordination of primate group movements by individual group members is generally categorized as leadership behavior, which entails several steps: deciding where to move next, initiating travel, and leading a group between food, water sources, and rest sites. Presumably, leaders are able to influence their daily foraging efficiency and nutritional intake, which could influence an individual's feeding ecology and long-term reproductive success. Within anthropoid species, females lead group movements in most female-bonded groups, while males lead groups in most nonfemale-bonded groups. Group leadership has not been described for social prosimians, which are typically not female-bonded. We describe group movements in two nonfemale-bonded, lemurid species living in southeastern Madagascar, Propithecus diadema edwardsi and Eulemur fulvus rufus. Although several social lemurids exhibit female dominance Eulemur fulvus rufus does not, and evidence for female dominance is equivocal in Propithecus diadema edwardsi. Given the ecological stresses that females face during reproduction, we predict that females in these two species will implement alternative behavioral strategies such as group leadership in conjunction with, or in the absence of, dominance interactions to improve access to food. We found that females in both species initiated and led group movements significantly more often than males did. In groups with multiple females, one female was primarily responsible for initiating and leading group movements. We conclude that female nutritional needs may determine ranging behavior to a large extent in these prosimian species, at least during months of gestation and lactation.
Jean-jacques Roeder - One of the best experts on this subject based on the ideXlab platform.
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Transitive inference in two lemur species (Eulemur macaco and Eulemur fulvus)
American Journal of Primatology, 2014Co-Authors: D. Tromp, Hélène Meunier, Jean-jacques RoederAbstract:When confronted with tasks involving reasoning instead of simple learning through trial and error, lemurs appeared to be less competent than simians. Our study aims to investigate lemurs' capability for transitive inference, a form of deductive reasoning in which the subject deduces logical conclusions from preliminary information. Transitive inference may have an adaptative function, especially in species living in large, complex social groups and is proposed to play a major role in rank estimation and establishment of dominance hierarchies. We proposed to test the capacities of reasoning using transitive inference in two species of lemurs, the brown lemur (Eulemur fulvus) and the black lemur (Eulemur macaco), both living in multimale–multifemale societies. For that purpose, we designed an original setup providing, for the first time in this kind of cognitive task, pictures of conspecifics' faces as stimuli. Subjects were trained to differentiate six photographs of unknown conspecifics named randomly from A to F to establish the order A > B > C > D > E > F and select consistently the highest-ranking photograph in five adjacent pairs AB, BC, CD, DE, and EF. Then lemurs were presented with the same adjacent pairs and three new and non-adjacent pairs BD, BE, CE. The results showed that all subjects correctly selected the highest-ranking photograph in every non-adjacent pair, reflecting lemurs' capacity for transitive inference. Our results are discussed in the context of the still debated current theories about the mechanisms underlying this specific capacity. Am. J. Primatol. 77:338–345, 2015. © 2014 Wiley Periodicals, Inc.
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Recognition of faces of known individuals in two lemur species (Eulemur fulvus and E. macaco)
Animal Behaviour, 2010Co-Authors: Laëtitia Maréchal, Emily Genty, Jean-jacques RoederAbstract:Three brown lemurs, Eulemur fulvus, and two black lemurs, Eulemur macaco, were trained to select consistently the photograph of the face of a known individual (KI: belonging to the same social group) when it was presented simultaneously with a photograph of the face of an unfamiliar individual (UI: belonging to another social group). After the learning phase, the subjects were presented with new pairs of photographs (KI versus UI: photographs that were not used in the learning phase), the same pairs presented in different associations, and finally pairs of photographs that were completely novel (50 different pairs). All the subjects selected the KI significantly more often than the UI under all conditions. Additional tests showed that the subjects preferentially selected photographs of a UI belonging to their own species versus a UI belonging to the other species. No preference was observed when the subjects were presented with two KI or with their own photograph associated with a UI. These results reveal that the face contains information allowing lemurs to discriminate familiar individuals from unfamiliar ones.
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can brown lemurs Eulemur fulvus learn to deceive a human competitor
Animal Cognition, 2008Co-Authors: Emilie Genty, Jane Foltz, Jean-jacques RoederAbstract:In the present study we asked whether lemurs could learn to manipulate information in order to deceive a human competitive trainer. Four brown lemurs were trained to communicate about the location of a hidden reward to a cooperative trainer, who rewarded the subject if he indicated the baited bowl. Next, a competitive trainer was introduced who kept the reward for himself if the subject indicated the baited bowl. In a first experiment, sessions were randomly assigned to be with either the cooperative or competitive trainer. No subject was able to show an efficient tactic with both trainers. In a second experiment, the participation of the two trainers was randomized across the trials for each session. When trials were mixed, one subject significantly chose baited location when interacting with the cooperative trainer, and reliably increased his choices of the unbaited location when presented with the competitive trainer. As with most other primate species tested under the same paradigm, associative learning may explain deceptive pointing by lemurs in this study.
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Transfer of self-control in black (Eulemur macaco) and brown (Eulemur fulvus) lemurs: choice of a less preferred food item under a reverse-reward contingency.
Journal of Comparative Psychology, 2007Co-Authors: Emilie Genty, Jean-jacques RoederAbstract:When presented a choice between two food-type arrays of equivalent size under a reverse-reward contingency, black (Eulemur macaco) and brown (Eulemur fulvus) lemurs transposed their self-control abilities, acquired in a previous experiment, to significantly select the less-desired food item in order to gain access to the more desired one. However, when presented with the choice between two different food-type arrays in which the amount of the less desired food array was larger than the more desired one, large individual differences were revealed: Some subjects established a consistent rule favoring quality or quantity, whereas others exhibited various point of trade-off. These results show that lemurs seem to manage the task considering not only food quantity but also food quality.
Hanitriniaina Rakotonirina - One of the best experts on this subject based on the ideXlab platform.
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The role of facial pattern variation for species recognition in red-fronted lemurs (Eulemur rufifrons).
BMC Evolutionary Biology, 2018Co-Authors: Hanitriniaina Rakotonirina, Peter M. Kappeler, Claudia FichtelAbstract:Species recognition, i.e., the ability to distinguish conspecifics from heterospecifics, plays an essential role in reproduction. The role of facial cues for species recognition has been investigated in several non-human primate species except for lemurs. We therefore investigated the role of facial cues for species recognition in wild red-fronted lemurs (Eulemur rufifrons) at Kirindy Forest. We presented adult red-fronted lemurs pictures of male faces from five species including red-fronted lemurs, three closely related species, white-fronted lemurs (E. albifrons), brown lemurs (E. fulvus), rufous brown lemurs (E. rufus), and genetically more distant red-bellied lemurs (E. rubriventer), occurring in allopatry with the study population. We predicted that red-fronted lemurs respond stronger to conspecific than to heterospecific pictures and that females show stronger responses than males. In addition, if genetic drift has played a role in the evolution of facial color patterns in the members of this genus, we predicted that responses of red-fronted lemurs correlate negatively with the genetic distance to the different species stimuli. Red-fronted lemurs looked significantly longer at pictures of their own species than at those of heterospecifics. Females spent less time looking at pictures of white-fronted, brown and red-bellied lemurs than males did, but not to pictures of red-bellied lemurs and a control stimulus. Individuals also exhibited sniffing behavior while looking at visual stimuli, and the time spent sniffing was significantly longer for pictures of conspecifics compared to those of heterospecifics. Moreover, the time spent looking and sniffing towards the pictures correlated negatively with the genetic distance between their own species and the species presented as stimulus. We conclude that red-fronted lemurs have the ability for species recognition using visual facial cues, which may allow them to avoid costly interbreeding. If so, sexual selection might have influenced the evolution of facial patterns in Eulemurs. Since responses also correlated with genetic distance, our findings suggest a potential role of genetic drift as well as sexual selection in influencing the evolution of facial variation in Eulemurs. Because study subjects looked and sniffed towards the presented pictures, red-fronted lemurs might have the ability for multi-modal species recognition.
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The role of facial pattern variation for species recognition in red-fronted lemurs (Eulemur rufifrons)
BMC, 2018Co-Authors: Hanitriniaina Rakotonirina, Peter M. Kappeler, Claudia FichtelAbstract:Abstract Background Species recognition, i.e., the ability to distinguish conspecifics from heterospecifics, plays an essential role in reproduction. The role of facial cues for species recognition has been investigated in several non-human primate species except for lemurs. We therefore investigated the role of facial cues for species recognition in wild red-fronted lemurs (Eulemur rufifrons) at Kirindy Forest. We presented adult red-fronted lemurs pictures of male faces from five species including red-fronted lemurs, three closely related species, white-fronted lemurs (E. albifrons), brown lemurs (E. fulvus), rufous brown lemurs (E. rufus), and genetically more distant red-bellied lemurs (E. rubriventer), occurring in allopatry with the study population. We predicted that red-fronted lemurs respond stronger to conspecific than to heterospecific pictures and that females show stronger responses than males. In addition, if genetic drift has played a role in the evolution of facial color patterns in the members of this genus, we predicted that responses of red-fronted lemurs correlate negatively with the genetic distance to the different species stimuli. Results Red-fronted lemurs looked significantly longer at pictures of their own species than at those of heterospecifics. Females spent less time looking at pictures of white-fronted, brown and red-bellied lemurs than males did, but not to pictures of red-bellied lemurs and a control stimulus. Individuals also exhibited sniffing behavior while looking at visual stimuli, and the time spent sniffing was significantly longer for pictures of conspecifics compared to those of heterospecifics. Moreover, the time spent looking and sniffing towards the pictures correlated negatively with the genetic distance between their own species and the species presented as stimulus. Conclusions We conclude that red-fronted lemurs have the ability for species recognition using visual facial cues, which may allow them to avoid costly interbreeding. If so, sexual selection might have influenced the evolution of facial patterns in Eulemurs. Since responses also correlated with genetic distance, our findings suggest a potential role of genetic drift as well as sexual selection in influencing the evolution of facial variation in Eulemurs. Because study subjects looked and sniffed towards the presented pictures, red-fronted lemurs might have the ability for multi-modal species recognition
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the role of acoustic signals for species recognition in redfronted lemurs Eulemur rufifrons
BMC Evolutionary Biology, 2016Co-Authors: Hanitriniaina Rakotonirina, Peter M. Kappeler, Claudia FichtelAbstract:Signals are essential for communication and play a fundamental role in the evolution and diversification of species. Olfactory, visual and acoustic species-specific signals have been shown to function for species recognition in non-human primates, but the relative contributions of selection for species recognition driven by sexual selection, natural selection, or genetic drift for the diversification of these signals remain largely unexplored. This study investigates the importance of acoustic signals for species recognition in redfronted lemurs (Eulemur rufifrons). We conducted playback experiments in both major populations of this species separated by several hundred kilometers: Kirindy Forest in the west and Ranomafana National Park in the east of Madagascar. The playback stimuli were composed of species-specific loud calls of E. rufifrons, three closely related species (E. albifrons, E. fulvus and E. rufus) and one genetically more distant species (E. rubriventer) that occurs in sympatry with eastern redfronted lemurs. We tested the ability of redfronted lemurs to discriminate conspecific from heterospecific loud calls by measuring the time spent looking towards the speaker after presentation of each loud call. We also tested the difference between female and male responses because loud calls may play a role in mate choice and the avoidance of heterospecific mating. Redfronted lemurs in Kirindy Forest did not discriminate their own loud calls from those of E. albifrons, E. fulvus and E. rufus, but they discriminated loud calls of E. rubriventer from their own. The Ranomafana population was tested only with three playback stimuli (E. rufifrons, E. albifrons, E. rubriventer) and did not discriminate between their own loud calls and those of E. albifrons and E. rubriventer. The response of females and males to playbacks did not differ in both populations. However, subjects in Ranomafana National Park responded more strongly to playback stimuli from E. rubriventer than subjects in Kirindy Forest. We conclude that in both populations individuals were not able to discriminate between loud calls of closely related species living in allopatry and that responses to more distantly related congeners are likely to be modulated by experience. Subjects in Ranomafana paid more attention to loud calls of syntopic E. rubriventer in comparison to the Kirindy subjects, suggesting that experience is important in facilitating discrimination. Because acoustic and genetic distances among Eulemurs are correlated, diversification in their acoustic signals might be the result of genetic drift.
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true lemurs true species species delimitation using multiple data sources in the brown lemur complex
BMC Evolutionary Biology, 2013Co-Authors: Matthias Markolf, Peter M. Kappeler, Claudia Fichtel, Hanitriniaina Rakotonirina, Phillip Von Grumbkow, Markus BrameierAbstract:Background Species are the fundamental units in evolutionary biology. However, defining them as evolutionary independent lineages requires integration of several independent sources of information in order to develop robust hypotheses for taxonomic classification. Here, we exemplarily propose an integrative framework for species delimitation in the “brown lemur complex” (BLC) of Madagascar, which consists of seven allopatric populations of the genus Eulemur (Primates: Lemuridae), which were sampled extensively across northern, eastern and western Madagascar to collect fecal samples for DNA extraction as well as recordings of vocalizations. Our data base was extended by including museum specimens with reliable identification and locality information for skull shape and pelage color analysis.