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Peter M. Kappeler - One of the best experts on this subject based on the ideXlab platform.
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Shared evolutionary origin of major histocompatibility complex polymorphism in sympatric lemurs
Molecular Ecology, 2017Co-Authors: Eva Kaesler, Peter M. Kappeler, Markus Brameier, Janina Demeler, Cornelia Kraus, Josué H. Rakotoniaina, Anni Hämäläinen, Elise HuchardAbstract:Genes of the Major Histocompatibility Complex (MHC) play a central role in adaptive immune responses of vertebrates. They exhibit remarkable polymorphism, often crossing species boundaries with similar alleles or allelic motifs shared across species. This pattern may reflect parallel parasite-mediated selective pressures, either favouring the long maintenance of ancestral MHC allelic lineages across successive speciation events by balancing selection (‘trans-species polymorphism’), or alternatively favouring the independent emergence of functionally similar alleles post-speciation via convergent evolution. Here we investigate the origins of MHC similarity across several species of dwarf and mouse lemurs (Cheirogaleidae). We examined MHC class II variation in two highly polymorphic loci (DRB, DQB) and evaluated the overlap of gut-parasite communities in four sympatric lemurs. We tested for parasite-MHC associations across species to determine whether similar parasite pressures may select for similar MHC alleles in different species. Next, we integrated our MHC data with those previously obtained from other Cheirogaleidae to investigate the relative contribution of convergent evolution and co-ancestry to shared MHC polymorphism by contrasting patterns of codon usage at functional versus neutral sites. Our results indicate that parasites shared across species may select for functionally similar MHC alleles, implying that the dynamics of MHC-parasite co-evolution should be envisaged at the community level. We further show that balancing selection maintaining trans-species polymorphism, rather than convergent evolution, is the primary mechanism explaining shared MHC sequence motifs between species that diverged up to 30 million years ago. This article is protected by copyright. All rights reserved.
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Agent-mediated spatial storage effect in heterogeneous habitat stabilizes competitive mouse lemur coexistence in Menabe Central, Western Madagascar
BMC Ecology, 2015Co-Authors: Livia Schäffler, Joachim Saborowski, Peter M. KappelerAbstract:Background Spatio-temporal distribution patterns of species in response to natural and anthropogenic drivers provide insight into the ecological processes that determine community composition. We investigated determinants of ecological structure in a species assemblage of 4 closely related primate species of the family Cheirogaleidae (Microcebus berthae, Microcebus murinus, Cheirogaleus medius, Mirza coquereli) in western Madagascar by extensive line transect surveys across spatial and temporal heterogeneities with the specific goal of elucidating the mechanisms stabilizing competitive coexistence of the two mouse lemur species (Microcebus spp.).
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Agent-mediated spatial storage effect in heterogeneous habitat stabilizes competitive mouse lemur coexistence in Menabe Central, Western Madagascar
BMC Ecology, 2015Co-Authors: Livia Schäffler, Joachim Saborowski, Peter M. KappelerAbstract:Background Spatio-temporal distribution patterns of species in response to natural and anthropogenic drivers provide insight into the ecological processes that determine community composition. We investigated determinants of ecological structure in a species assemblage of 4 closely related primate species of the family Cheirogaleidae ( Microcebus berthae , Microcebus murinus, Cheirogaleus medius, Mirza coquereli ) in western Madagascar by extensive line transect surveys across spatial and temporal heterogeneities with the specific goal of elucidating the mechanisms stabilizing competitive coexistence of the two mouse lemur species ( Microcebus spp.). Results Interspecific competition between the mouse lemurs was indicated by negative spatial associations in degraded habitat and by habitat partitioning along anthropogenic disturbance gradients during dry seasons with resource scarcity. In non-degraded habitat, intraguild predator M. coquereli , but not C. medius, was negatively associated with M. murinus on the population level, whereas its regional distribution overlapped spatially with that of M. berthae . The species’ interspecific distribution pattern across spatial and temporal heterogeneities corresponded to predictions for agent-mediated coexistence and thus confirmed M. coquereli ’s stabilizing impact on the coexistence of mouse lemurs. Conclusions Interspecific interactions contribute to ecological structure in this cheirogaleid assemblage and determinants vary across spatio-temporal heterogeneities. Coexistence of Microcebus spp. is stabilized by an agent-mediated spatial storage effect: M. coquereli creates refuges from competition for M. berthae in intact habitat, whereas anthropogenic environments provide M. murinus with an escape from resource competition and intraguild predation. Species persistence in the assemblage therefore depends on the conservation of habitat content and context that stabilizing mechanisms rely on. Our large-scale population level approach did not allow for considering all potential functional and stochastic drivers of ecological structure, a key limitation that accounts for the large proportion of unexplained variance in our models.
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Two New Species of Mouse Lemurs (Cheirogaleidae: Microcebus) from Eastern Madagascar
International Journal of Primatology, 2013Co-Authors: Rodin M. Rasoloarison, David W. Weisrock, Anne D. Yoder, Daniel Rakotondravony, Peter M. KappelerAbstract:The number of newly discovered Malagasy vertebrate taxa has multiplied in recent years, emphasizing the importance of complete taxon sampling for phylogenetics, biogeography, functional ecology, and conservation biology, especially in such a biodiversity hotspot. In particular, the diversity of extant lemurs is much higher than previously thought, and we have yet to comprehend fully the full extent of lemuriform biodiversity. A recent genetic analysis of mtDNA and nDNA sequence data in Malagasy mouse lemurs revealed the existence of several novel mtDNA clades based on new field sampling. These geographically defined and previously unrecognized mtDNA clades corresponded precisely to patterns of population structure revealed in the analysis of the nDNA data, thus confirming their evolutionary divergence from other mouse lemur clades. Two of these independently evolving lineages correspond to specimens that were collected by us in the Marolambo and Manantantely/Ivorona regions. Here we summarize the genetic evidence and report on the morphometric and external characteristics of these animals, formally describing them as new species. This report thus brings the number of currently recognized and described mouse lemur species to 20. The forests in which these mouse lemurs were discovered have been heavily degraded in the past decade, prompting the classification of one of the new species as Endangered by the IUCN, even before its formal description. As with several other newly described lemur species, immediate field studies and appropriate conservation actions are therefore urgent.
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Concatenation and concordance in the reconstruction of mouse lemur phylogeny: an empirical demonstration of the effect of allele sampling in phylogenetics
Molecular Biology and Evolution, 2012Co-Authors: David W. Weisrock, Peter M. Kappeler, Stacey D. Smith, Lauren M. Chan, Karla Biebouw, Anne D. YoderAbstract:The systematics and speciation literature is rich with discussion relating to the potential for gene tree/species tree discordance. Numerous mechanisms have been proposed to generate discordance, including differential selection, longbranch attraction, gene duplication, genetic introgression, and/or incomplete lineage sorting. For speciose clades in which divergence has occurred recently and rapidly, recovering the true species tree can be particularly problematic due to incomplete lineage sorting. Unfortunately, the availability of multilocus or ‘‘phylogenomic’’ data sets does not simply solve the problem, particularly when the data are analyzed with standard concatenation techniques. In our study, we conduct a phylogenetic study for a nearly complete species sample of the dwarf and mouse lemur clade, Cheirogaleidae. Mouse lemurs (genus, Microcebus) have been intensively studied over the past decade for reasons relating to their high level of cryptic species diversity, and although there has been emerging consensus regarding the evolutionary diversity contained within the genus, there is no agreement as to the inter-specific relationships within the group. We attempt to resolve cheirogaleid phylogeny, focusing especially on the mouse lemurs, by employing a large multilocus data set. We compare the results of Bayesian concordance methods with those of standard gene concatenation, finding that though concatenation yields the strongest results as measured by statistical support, these results are found to be highly misleading. By employing an approach where individual alleles are treated as operational taxonomic units, we show that phylogenetic results are substantially influenced by the selection of alleles in the concatenation process.
Anne D. Yoder - One of the best experts on this subject based on the ideXlab platform.
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Two New Species of Mouse Lemurs (Cheirogaleidae: Microcebus) from Eastern Madagascar
International Journal of Primatology, 2013Co-Authors: Rodin M. Rasoloarison, David W. Weisrock, Anne D. Yoder, Daniel Rakotondravony, Peter M. KappelerAbstract:The number of newly discovered Malagasy vertebrate taxa has multiplied in recent years, emphasizing the importance of complete taxon sampling for phylogenetics, biogeography, functional ecology, and conservation biology, especially in such a biodiversity hotspot. In particular, the diversity of extant lemurs is much higher than previously thought, and we have yet to comprehend fully the full extent of lemuriform biodiversity. A recent genetic analysis of mtDNA and nDNA sequence data in Malagasy mouse lemurs revealed the existence of several novel mtDNA clades based on new field sampling. These geographically defined and previously unrecognized mtDNA clades corresponded precisely to patterns of population structure revealed in the analysis of the nDNA data, thus confirming their evolutionary divergence from other mouse lemur clades. Two of these independently evolving lineages correspond to specimens that were collected by us in the Marolambo and Manantantely/Ivorona regions. Here we summarize the genetic evidence and report on the morphometric and external characteristics of these animals, formally describing them as new species. This report thus brings the number of currently recognized and described mouse lemur species to 20. The forests in which these mouse lemurs were discovered have been heavily degraded in the past decade, prompting the classification of one of the new species as Endangered by the IUCN, even before its formal description. As with several other newly described lemur species, immediate field studies and appropriate conservation actions are therefore urgent.
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Concatenation and concordance in the reconstruction of mouse lemur phylogeny: an empirical demonstration of the effect of allele sampling in phylogenetics
Molecular Biology and Evolution, 2012Co-Authors: David W. Weisrock, Peter M. Kappeler, Stacey D. Smith, Lauren M. Chan, Karla Biebouw, Anne D. YoderAbstract:The systematics and speciation literature is rich with discussion relating to the potential for gene tree/species tree discordance. Numerous mechanisms have been proposed to generate discordance, including differential selection, longbranch attraction, gene duplication, genetic introgression, and/or incomplete lineage sorting. For speciose clades in which divergence has occurred recently and rapidly, recovering the true species tree can be particularly problematic due to incomplete lineage sorting. Unfortunately, the availability of multilocus or ‘‘phylogenomic’’ data sets does not simply solve the problem, particularly when the data are analyzed with standard concatenation techniques. In our study, we conduct a phylogenetic study for a nearly complete species sample of the dwarf and mouse lemur clade, Cheirogaleidae. Mouse lemurs (genus, Microcebus) have been intensively studied over the past decade for reasons relating to their high level of cryptic species diversity, and although there has been emerging consensus regarding the evolutionary diversity contained within the genus, there is no agreement as to the inter-specific relationships within the group. We attempt to resolve cheirogaleid phylogeny, focusing especially on the mouse lemurs, by employing a large multilocus data set. We compare the results of Bayesian concordance methods with those of standard gene concatenation, finding that though concatenation yields the strongest results as measured by statistical support, these results are found to be highly misleading. By employing an approach where individual alleles are treated as operational taxonomic units, we show that phylogenetic results are substantially influenced by the selection of alleles in the concatenation process.
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Development and application of a phylogenomic toolkit: Resolving the evolutionary history of Madagascar’s lemurs
Genome Research, 2008Co-Authors: Julie E. Horvath, Peter M. Kappeler, David W. Weisrock, Stephanie L. Embry, Isabella Fiorentino, James P. Balhoff, Gregory A. Wray, Huntington F. Willard, Anne D. YoderAbstract:Lemurs and the other strepsirrhine primates are of great interest to the primate genomics community due to their phylogenetic placement as the sister lineage to all other primates. Previous attempts to resolve the phylogeny of lemurs employed limited mitochondrial or small nuclear data sets, with many relationships poorly supported or entirely unresolved. We used genomic resources to develop 11 novel markers from nine chromosomes, representing ∼9 kb of nuclear sequence data. In combination with previously published nuclear and mitochondrial loci, this yields a data set of more than 16 kb and adds ∼275 kb of DNA sequence to current databases. Our phylogenetic analyses confirm hypotheses of lemuriform monophyly and provide robust resolution of the phylogenetic relationships among the five lemuriform families. We verify that the genus Daubentonia is the sister lineage to all other lemurs. The Cheirogaleidae and Lepilemuridae are sister taxa and together form the sister lineage to the Indriidae; this clade is the sister lineage to the Lemuridae. Divergence time estimates indicate that lemurs are an ancient group, with their initial diversification occurring around the Cretaceous-Tertiary boundary. Given the power of this data set to resolve branches in a notoriously problematic area of primate phylogeny, we anticipate that our phylogenomic toolkit will be of value to other studies of primate phylogeny and diversification. Moreover, the methods applied will be broadly applicable to other taxonomic groups where phylogenetic relationships have been notoriously difficult to resolve. [Supplemental material is available online at www.genome.org. The sequence data from this study have been submitted to GenBank under accession nos. EU057196–EU057514 and EU342218–EU342345.]
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THE USE OF PHYLOGENY FOR RECONSTRUCTING LEMSJRIFORM BIOGEOGRAPEW
1996Co-Authors: Anne D. YoderAbstract:t ABSTRACT.- The Malagasy primates (Infiaorder Lemuriformes) are a highly diverse taxonomic assemblage whose phylogenetic aftinities have been the subject of extended debate. There have been ' . nwnerous proposals to suggest that the lemuriforms are not monophyletic and that there have been multiple migrations of primates between Madagascar and other land masses during primate evolutionary history. The phylogenetic analysis of a comprehensive morphological data set and DNA sequences from the complete mitochondrial cytochrome b gene suggests otherwise, however. These data, whether analyzed separately or together, give support to the hypothesis that the Malagasy primates, including the family Cheirogaleidae and the genus Daubentonia, are monophyletic. A distance analysis of the cytochrome b data further suggests that lemurs arrived on Madagascar and began to divers@ by the early Eocene. Current species distributions and phylogenetic branching patterns indicate that the lemuriform stem lineage originated on Afrca and probably traveled to Madagascar via rafting. KEY-W0RDS.- Primates, Strepsirrhini, Phylogeny, Evolutionary rates, Biogeography RESUME.- Les Primates malgaches (Lemuriformes) representent un assemblage taxonomique extremement diverse .dont les aiTinites phylogenetiques ont ete le sujet de larges debats. L'idee qu'ils ne representait pas une lignee monophyletique et qu'il y a eu de nombreuses migrations de Primates entre Madagascar et d'autres continents pendant l'histoire de leur evolution a souvent ete avancee. L'analyse phylogenetique des donnees morphologiques detaillees et des sequences de ADN provenant du gene mitochondrial b contredit cependant ces hypotheses. Qu'elles soient analysees separement ou ensemble, ces donnees soutiennent l'idee que les Primates malgaches y compris la famille des Cheirogaleidae et le genre Daubentonia, sont monophyletiques. L'analyse des donnees du cytochrome b suggere davantage que les Lemuriens sont arrives a Madagascar et ont commence a se diversifier au debut de 1'Eocene. Les distributions actuelles des especes et les modeles phylogenetiques indiquent que la souche des Lemuriens a son origine en Afrique et a probablement atteint Madagascar par radeaux. MOTS-CLES.- Primates, Strepsirrhini, Phylogenie, Taux evolutif$ Biogeographie
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relative position of the Cheirogaleidae in strepsirhine phylogeny a comparison of morphological and molecular methods and results
American Journal of Physical Anthropology, 1994Co-Authors: Anne D. YoderAbstract:An examination of previous morphological and molecular studies of strepsirhine systematics suggests a conflict between the two types of data. Cladistic analyses of morphological data have indicated that the Malagasy primate family Cheirogaleidae is the sister taxon of the Afro-Asian lorisiforms and that together, cheirogaleids and lorisiforms comprise a monophyletic clade that excludes the Malagasy lemuriforms. Molecular studies, on the other hand, have consistently found that cheirogaleids and lemuriforms together are monophyletic to the exclusion of lorisiforms. Both types of studies, however, have suffered from methodological weaknesses: the morphological studies looked at too few characters and the molecular studies looked at too few taxa. This study examines a large and diverse morphological data set as well as molecular data from a comprehensive sample of strepsirhine taxa. The data sets are considered independently and jointly. When they are analyzed independently, the morphological data give weak support, and the molecular data strong support, to the hypothesis of Malagasy primate monophyly. When the two data sets are combined in a single analysis, the results are decisive. The “total evidence” approach yields compelling support to the hypothesis that cheirogaleids and remaining Malagasy lemuriforms comprise a monophyletic assemblage that excludes lorisiforms. © 1994 Wiley-Liss, Inc.
Julia Ostner - One of the best experts on this subject based on the ideXlab platform.
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big times for dwarfs social organization sexual selection and cooperation in the Cheirogaleidae
Evolutionary Anthropology, 2005Co-Authors: Oliver Schulke, Julia OstnerAbstract:The latest phylogenetic reconstructions place the cheirogaleid family very close to the root of the lemur tree.3 Today most authors agree that Madagascar was colonized in a single event, that lemurs are monophyletic, and that the aye-aye, Daubentonia madagascariensis, diverged first from their ancestral stock.4–7 Cheirogaleidae probably were the second family that branched off,3,8 which would support the notion that they retained many characters that are ancestral to all lemurs and primates in general. In addition to the smallest living primates, those of the genus Microcebus (8 species), the family Cheirogaleidae comprises four genera: Phaner (4 species), Cheirogaleus (7 species), Mirza (1 species), and Allocebus (1 species) (Fig. 1). Morphological and genetic traits, but not behavioral traits, suggest that Phaner may be classified as a subfamily or even a separate family.9,10 (Taxonomy within genera has changed rapidly. The first systematic studies covering large areas of the distribution demonstrated high species diversity in Microcebus11,12 and Cheirogaleus,13 and elevated subspecies to the species level in Phaner.14) As a family, the cheirogaleids have colonized the entire Island of Madagascar (Fig. 2), inhabiting the spiny forest and dry forests in the south and west, and wet evergreen forests and marsh habitats in the east and north.15
Jennifer Pastorini - One of the best experts on this subject based on the ideXlab platform.
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molecular phylogeny of the lemur family Cheirogaleidae primates based on mitochondrial dna sequences
Molecular Phylogenetics and Evolution, 2001Co-Authors: Elke Zimmermann, Jennifer Pastorini, Robert D Martin, Petra Ehresmann, Michael R J ForstnerAbstract:Abstract Cheirogaleidae currently comprises five genera whose relationships remain contentious. The taxonomic status and phylogenetic position of both Mirza coquereli and Allocebus trichotis are still unclear. The taxonomic status of the recently discovered Microcebus ravelobensis (a sympatric sibling species of Microcebus murinus) and its phylogenetic position also require further examination. A ∼2.4-kb mitochondrial DNA sequence including part of the COIII gene, complete ND3, ND4L, and ND4 genes, and 5 tRNAs was used to clarify relationships among cheirogaleids. Mirza and Microcebus form a clade representing the sister group of Allocebus, with a clade containing Cheirogaleus major and Cheirogaleus medius diverging first. M. ravelobensis and Microcebus rufus form a subclade within Microcebus, with M. murinus as its sister group. The molecular data support the generic status of Mirza coquereli and species-level divergence of M. ravelobensis. Furthermore, “M. rufus” may well represent more than one species.
Lance A Durden - One of the best experts on this subject based on the ideXlab platform.
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a new species of sucking louse phthiraptera anoplura polyplacidae from the gray mouse lemur microcebus murinus primates Cheirogaleidae in madagascar
Journal of Medical Entomology, 2018Co-Authors: Lance A Durden, Sharon E Kessler, Ute Radespiel, Elke Zimmermann, Alida F Hasiniaina, Sarah ZohdyAbstract:Lemurpediculus madagascariensis sp. nov. (Phthiraptera: Anoplura: Polyplacidae) is described from the Gray Mouse lemur, Microcebus murinus (J. F. Miller) (Primates: Cheirogaleidae), from Ankarafantsika National Park, Madagascar. Lemurs were trapped using Sherman Live Traps and visually inspected for lice, which were preserved in 90% ethanol. Adults of both sexes and the third-instar nymph of the new species are illustrated and distinguished from the four previously known species of Lemurpediculus: L. verruculosus (Ward); L. petterorum Paulian; L. claytoni Durden, Blanco, and Seabolt; and L. robbinsi Durden, Blanco, and Seabolt. It is not known if the new species of louse is a vector of any pathogens or parasites.
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two new species of sucking lice phthiraptera anoplura polyplacidae from endangered hibernating lemurs primates Cheirogaleidae
Journal of Medical Entomology, 2017Co-Authors: Lance A Durden, Marina B Blanco, Matthew H SeaboltAbstract:: Lemurpediculus robbinsi sp. nov. is described from Crossley's dwarf lemur, Cheirogaleus crossleyi A. Grandidier, and Lemurpediculus claytoni sp. nov. is described from Sibree's dwarf lemur, Cheirogaleus sibreei Forsyth Major, from Madagascar. Both sexes of each new louse species are illustrated and distinguished from the two previously known species of Lemurpediculus: L. verruculosus (Ward) and L. petterorum Paulian. With the addition of two new species to the genus, an amended description of Lemurpediculus is provided. The two hosts of the new louse species are morphologically similar, endangered, obligately hibernating lemurs. These two species of lemurs are sometimes sympatric in rainforests in eastern Madagascar. Despite the morphological similarity of the two host species, their lice are morphologically distinct and are easiest to identify based on the shape of the subgenital plate of the female and the shape of the genitalia in the male. Both new species of lice should be considered to be endangered because their hosts are endangered. It is not known if either of the new species of lice are vectors of pathogens or parasites to their hosts.
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genetic diversity of ixodid ticks parasitizing eastern mouse and dwarf lemurs in madagascar with descriptions of the larva nymph and male of ixodes lemuris acari ixodidae
Journal of Parasitology, 2013Co-Authors: Marina B Blanco, Lance A Durden, Mostafa A Elfawal, Lorenza Beati, Guang Xu, Laurie R Godfrey, Stephen M RichAbstract:Abstract: The ixodid ticks parasitizing small-bodied nocturnal mouse and dwarf lemurs (Primates, Cheirogaleidae) in Madagascar are poorly documented. At Tsinjoarivo, a high-altitude eastern rain forest, mouse and dwarf lemurs were parasitized by ixodid ticks. At Ranomafana, a montane southeastern rain forest, dwarf lemurs hosted a species of Ixodes, whereas mouse lemurs were parasitized by Haemaphysalis lemuris. Ixodes specimens represent all active stages, and females are morphologically consistent with previous descriptions of Ixodes lemuris females, the only described stage in the literature. Morphological comparisons and genetic analysis using fragments of COI gene confirm that all Ixodes ticks from Tsinjoarivo and Ranomafana forests belong to the same species, i.e., Ixodes lemuris. Thus, we are able to provide descriptions of the previously unknown larva, nymph, and male. Mouse lemurs at both locations were parasitized only by immature stages of I. lemuris (at Tsinjoarivo) or H. lemuris (at Ranomafa...