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Nayuta Yamashita - One of the best experts on this subject based on the ideXlab platform.

  • molar morphology and variation in two malagasy lemur families lemuridae and Indriidae
    Journal of Human Evolution, 1998
    Co-Authors: Nayuta Yamashita
    Abstract:

    Abstract The lemurs of Madagascar represent a radiation of primates exhibiting considerable ecological and morphological diversity. Dentally, all lemurs possess the characteristic strepsirhine anterior tooth comb, but exhibit variation in their postcanine teeth that may be related to dietary differences. In this study, I examine two factors that could complicate a strictly functional interpretation of tooth form variation in two families of Malagasy primates, the Lemuridae and Indriidae. (1) Allometry may be responsible for observed variation. Body size, not specific tooth features, may be the object of selection; tooth features may vary among taxa as a consequence of differences in body size. (2) Taxonomic affiliation may “explain” variation without recourse to functional explanations. Tooth morphology among closely-related taxa may be constrained developmentally or as a result of stabilizing selection. Morphological variation between families, therefore, may not be the result of current functional differences related to physical dietary properties, but may result from past events that are lineage-specific. Morphological features from the upper and lower second molars of seven lemurid and four indriid taxa are compared. The results of this study indicate that the majority of second molar features scale isometrically. Initial separation by families is warranted by the homogeneous slopes but different elevations in analyses of covariance between families. Intrafamilial variation is considerable for lemurids, but more discrete among indriids. Functional explanations for tooth form variability should take into consideration the degree of variation within taxa. For this particular dataset, the two families should be analyzed separately, and, because of the considerable overlap of subspecies with full species among lemurids, the lowest taxonomic unit recognized should be used.

  • Seasonally and site specificity of mechanical dietary patterns in two malagasy lemur families (Lemuridae and Indriidae)
    International Journal of Primatology, 1996
    Co-Authors: Nayuta Yamashita
    Abstract:

    Relationships between tooth morphology and physical food properties are well established. Because food breakdown is initiated by the dentition, one may posit that variations in tooth form are related functionally to the physical demands placed on them by the diet. Yet classification of diets as leaves, fruits , and insects does not adequately describe foods in mechanically significant ways. Furthermore, physical dietary properties have not been well quantified. I describe patterns of two physical food properties — hardness and shear strength — in the diets of five lemur taxa in Madagascar— Propithecus diadema edwardsi, Lemur fulvus rufus, and Lemur rubriventer— in the rain forest site of Ranomafana National Park and Propithecus v. verreauxi and Lemur catta at the dry forest site of Beza Mahafaly special reserve. I compared mean plant values for each lemur taxon, the most stressful foods eaten and the amount of time spent feeding on each dietary item. Variation in food hardness is a site phenomenon with fluctuations within sites. Shear strength is strongly seasonal. Lemur diets, as traditionally classified, are not mechanically uniform since frugivores and folivores could be separated on the basis of the physical properties of their foods. Finally, I assign taxa to dietary categories that are mechanically descriptive and derive several predictions regarding expected tooth morphologies from them .

Christian Roos - One of the best experts on this subject based on the ideXlab platform.

  • An Alu-Based Phylogeny of Lemurs (Infraorder: Lemuriformes)
    PLOS ONE, 2012
    Co-Authors: Adam T Mclain, Scott W. Herke, J. Michael Oldenburg, Matthew G. Bourgeois, Camille F. Abshire, Christian Roos, Christopher Faulk, Mark A Batzer
    Abstract:

    Lemurs (infraorder: Lemuriformes) are a radiation of strepsirrhine primates endemic to the island of Madagascar. As of 2012, 101 lemur species, divided among five families, have been described. Genetic and morphological evidence indicates all species are descended from a common ancestor that arrived in Madagascar ∼55–60 million years ago (mya). Phylogenetic relationships in this species-rich infraorder have been the subject of debate. Here we use Alu elements, a family of primate-specific Short INterspersed Elements (SINEs), to construct a phylogeny of infraorder Lemuriformes. Alu elements are particularly useful SINEs for the purpose of phylogeny reconstruction because they are identical by descent and confounding events between loci are easily resolved by sequencing. The genome of the grey mouse lemur (Microcebus murinus) was computationally assayed for synapomorphic Alu elements. Those that were identified as Lemuriformes-specific were analyzed against other available primate genomes for orthologous sequence in which to design primers for PCR (polymerase chain reaction) verification. A primate phylogenetic panel of 24 species, including 22 lemur species from all five families, was examined for the presence/absence of 138 Alu elements via PCR to establish relationships among species. Of these, 111 were phylogenetically informative. A phylogenetic tree was generated based on the results of this analysis. We demonstrate strong support for the monophyly of Lemuriformes to the exclusion of other primates, with Daubentoniidae, the aye-aye, as the basal lineage within the infraorder. Our results also suggest Lepilemuridae as a sister lineage to Cheirogaleidae, and Indriidae as sister to Lemuridae. Among the Cheirogaleidae, we show strong support for Microcebus and Mirza as sister genera, with Cheirogaleus the sister lineage to both. Our results also support the monophyly of the Lemuridae. Within Lemuridae we place Lemur and Hapalemur together to the exclusion of Eulemur and Varecia, with Varecia the sister lineage to the other three genera.

  • Comparing chromosomal and mitochondrial phylogenies of the Indriidae (Primates, Lemuriformes)
    Chromosome Research, 2011
    Co-Authors: Y Rumpler, Christian Roos, Marcel Hauwy, Jean-luc Fausser, Alphonse Zaramody, Nicole Andriaholinirina, Dietmar Zinner
    Abstract:

    The Malagasy primate family Indriidae comprises three genera with up to 19 species. Cytogenetic and molecular phylogenies of the Indriidae have been performed with special attention to the genus Propithecus . Comparative R-banding and FISH with human paints were applied to karyotypes of representatives of all three genera and confirmed most of the earlier R-banding results. However, additional chromosomal rearrangements were detected. A reticulated and a cladistic phylogeny, the latter including hemiplasies, have been performed. Cladistic analysis of cytogenetic data resulted in a phylogenetic tree revealing (1) monophyly of the family Indriidae, (2) monophyly of the genus Avahi , (3) sister–group relationships between Propithecus diadema and Propithecus edwardsi , and (4) the grouping of the latter with Indri indri , Propithecus verreauxi , and Propithecus tattersalli , and thus suggesting paraphyly of the genus Propithecus . A molecular phylogeny based on complete mitochondrial cytochrome b sequences of 16 species indicated some identical relationships, such as the monophyly of Avahi and the sister–group relationships of the eastern ( P. diadema and P. edwardsi ) to the western Propithecus species ( P. verreauxi , Propithecus coquereli , and P. tattersalli ). However, the main difference between the molecular and cytogenetic phylogenies consists in an early divergence of Indri in the molecular phylogeny while in the chromosomal phylogeny it is nested within Propithecus . The similarities and differences between molecular and cytogenetic phylogenies in relation to data on the species’ geographic distributions and mating systems allow us to propose a scenario of the evolution of Indriidae. Chromosomal and molecular processes alone or in combination created a reproductive barrier that was then followed by further speciation processes.

  • Primate jumping genes elucidate strepsirrhine phylogeny.
    Proceedings of the National Academy of Sciences of the United States of America, 2004
    Co-Authors: Christian Roos, Jürgen Schmitz, Hans Zischler
    Abstract:

    Transposable elements provide a highly informative marker system for analyzing evolutionary histories. To solve controversially discussed topics in strepsirrhine phylogeny, we characterized 61 loci containing short interspersed elements (SINEs) and determined the SINE presence–absence pattern at orthologous loci in a representative strepsirrhine panel. This SINE monolocus study was complemented by a Southern blot analysis tracing multiple loci of two different strepsirrhine specific SINEs. The results thereof were combined with phylogenetic trees reconstructed on the basis of complete mitochondrial cytochrome b sequences from all recognized strepsirrhine genera. Here we present evidence for (i) a sister group relationship of Malagasy Chiromyiformes and Lemuriformes, (ii) Lorisidae being a monophyletic sister clade to the Galagidae, and (iii) common ancestry of African and Asian lorisids. Based on these findings, we conclude that strepsirrhines originated in Africa and that Madagascar and Asia were colonized by respective single immigration events. In agreement with paleocontinental data, the molecular analyses suggest a crossing of the Mozambique channel by rafting between the late Cretaceous and the middle Eocene, whereas Asia was most likely colonized between the early Eocene and the middle Oligocene on a continental route. Furthermore, one SINE integration links the two Lemuriformes families, Lemuridae and Indriidae, indicating a common origin of diurnality or cathemerality and a later reversal to nocturnality by the indriid genus Avahi.

Cathy V. Williams - One of the best experts on this subject based on the ideXlab platform.

  • ectoparasites of propithecus diadema primates Indriidae with notes on unusual attachment site selection by haemaphysalis lemuris parasitiformes ixodidae
    Journal of Medical Entomology, 2015
    Co-Authors: Hans Klompen, Randall E. Junge, Cathy V. Williams
    Abstract:

    An examination of ectoparasite loads in two populations of wild diademed sifakas, Propithecus diadema Bennett, yielded seven species-four mite species, a louse, a hippoboscid fly, and a leech. Prevalence of the tick Haemaphysalis lemuris Hoogstraal, the mites Liponyssella madagascariensis (Hirst) and Lemuralges propithecus Bochkov et al., and the louse Trichophilopterus babakotophilus Stobbe was quite high, at least 20%. H. lemuris was the most common ectoparasite in one population, while completely absent in a second one. When present, the most common attachment site for H. lemuris males was in the nares of their hosts.

  • Lemuralges propithecus sp. n. (Acariformes: Psoroptidae), an ectoparasite of the diademed sifaka Propithecus diadema (Primates: Indriidae).
    Folia parasitologica, 2015
    Co-Authors: Andre V. Bochkov, Hans Klompen, Randall E. Junge, Cathy V. Williams
    Abstract:

    A new species of the genus Lemuralges Fain, 1963 (Acariformes: Psoroptidae: Makialginae) is described from the Malagasy lemur Propithecus diadema (Bennett) (Primates: Indriidae) based on all postembryonic instars. This new species differs from the only known species in this genus, Lemuralges intermedius Fain, 1963, by the following features: both sexes of L. propithecus sp. n. show a pair of medioventral projections of the subcapitulum (vs without projections in L. intermedius) and the propodonotal shield is slightly ornamented (vs unornamented); in males the hysteronotal shield is completely covered by longitudinal striae (vs median part without striae), setae c2 are 120-140 µm long (vs 200-210 µm long), and femur III has a short transverse furrow dorsally (vs a longitudinal furrow); in females, setae h2 are, at least, 2 times shorter than h3 (vs slightly longer, or subequal to, h3), tibia IV has a ventro-apical projection (vs without projection). Larvae and protonymphs of the new species show some unique developmental delays. Female and male tritonymphs differ by their external morphology.

Y Rumpler - One of the best experts on this subject based on the ideXlab platform.

  • Comparing chromosomal and mitochondrial phylogenies of the Indriidae (Primates, Lemuriformes)
    Chromosome Research, 2011
    Co-Authors: Y Rumpler, Christian Roos, Marcel Hauwy, Jean-luc Fausser, Alphonse Zaramody, Nicole Andriaholinirina, Dietmar Zinner
    Abstract:

    The Malagasy primate family Indriidae comprises three genera with up to 19 species. Cytogenetic and molecular phylogenies of the Indriidae have been performed with special attention to the genus Propithecus . Comparative R-banding and FISH with human paints were applied to karyotypes of representatives of all three genera and confirmed most of the earlier R-banding results. However, additional chromosomal rearrangements were detected. A reticulated and a cladistic phylogeny, the latter including hemiplasies, have been performed. Cladistic analysis of cytogenetic data resulted in a phylogenetic tree revealing (1) monophyly of the family Indriidae, (2) monophyly of the genus Avahi , (3) sister–group relationships between Propithecus diadema and Propithecus edwardsi , and (4) the grouping of the latter with Indri indri , Propithecus verreauxi , and Propithecus tattersalli , and thus suggesting paraphyly of the genus Propithecus . A molecular phylogeny based on complete mitochondrial cytochrome b sequences of 16 species indicated some identical relationships, such as the monophyly of Avahi and the sister–group relationships of the eastern ( P. diadema and P. edwardsi ) to the western Propithecus species ( P. verreauxi , Propithecus coquereli , and P. tattersalli ). However, the main difference between the molecular and cytogenetic phylogenies consists in an early divergence of Indri in the molecular phylogeny while in the chromosomal phylogeny it is nested within Propithecus . The similarities and differences between molecular and cytogenetic phylogenies in relation to data on the species’ geographic distributions and mating systems allow us to propose a scenario of the evolution of Indriidae. Chromosomal and molecular processes alone or in combination created a reproductive barrier that was then followed by further speciation processes.

  • interspecific nucleotide sequence differences in the cytochrome b gene of Indriidae primates strepsirhini
    Primates, 2000
    Co-Authors: Hanta Razafindraibe, Daniel Montagnon, Berthine I Ravoarimanana, Y Rumpler
    Abstract:

    The comparison of partial sequence of the mitochondrial cytochrome b gene nucleotides for different Indriidae allowed us to confirm the species status ofAvahi laniger, A. occidentalis, and Propithecus tattersalli. The nucleotide sequence allowed also to propose a phylogenetic tree which is discussed taking into account morphological, cytogenetic and former molecular biology data.

  • phylogenetic relationships among Indriidae primates strepsirhini inferred from highly repeated dna band patterns
    Comptes Rendus De L Academie Des Sciences Serie Iii-sciences De La Vie-life Sciences, 1997
    Co-Authors: Hanta Razafindraibe, Daniel Montagnon, Y Rumpler
    Abstract:

    Comparative studies of highly repeated DNA from different species of Indriidae (Primates, Strepsirhini) allowed confirmation of the specific status of Avahi occidentalis, A. laniger and Propithecus tattersalli. The comparison of their band patterns revealed the existence of specific and common bands from which a cladogram of the family is inferred. This cladogram shows that Avahi clade is the sister-group of Indri and Propithecus clade, and that P. verreauxi is related to P. diadema. These results were discussed in view of those obtained from cytogenetic, morphological and molecular data (mitochondrial DNA). This study shows the capacity of the repeated sequence pattern comparison to be used as a tool for confirming taxa status, (taxinomic classification is a primary determinant of management priorities for endangered species, neglect of distinct taxa may lead to their extinction), and for inferring phylogenetic relationships among related species.

Shawn M. Lehman - One of the best experts on this subject based on the ideXlab platform.

  • ecological and phylogenetic correlates to body size in the Indriidae
    International Journal of Primatology, 2007
    Co-Authors: Shawn M. Lehman
    Abstract:

    I investigated ecological and phylogenetic correlates to body size variations in 10 taxa of extant Indriidae (Indri, Avahi, and Propithecus). I also tested for phylogenetic niche conservatism as a model for the evolution of indriid body size. Phylogenetic niche conservatism refers to the shared attributes that related taxa have acquired because they tend to have occupied similar niches during their evolutionary history. I collected species-specific data on body mass, climate, density, and chemical properties of food items from the literature. I used 2 phylogenies in independent contrasts methods to control for phylogenetic relationships (Indri and Propithecus as sister taxa vs. Indri basal taxa to all indriids). Multivariate models indicated that lemur density and resource quality are the strongest ecological correlates to indriid body size variations. Partitioning methods revealed that 52.4–67% of indriid body size variation is explained by phylogenetic niche conservation. Thus, indriid body size variations may be the result of stabilizing selection. Though it is possible to identify constraints on lower than average body size, there are few data on selection against larger than average body size in indriids. Large body size in subfossil lemurs further complicates identification of constraints on larger than average body size in extant indriids. Researchers using independent contrast methods to control for phylogeny should be aware that some ecology-phenotype relationships are best explained as the result of the synergistic effects of ecology and phylogeny.

  • Ecological and Phylogenetic Correlates to Body Size in the Indriidae
    2005
    Co-Authors: Shawn M. Lehman
    Abstract:

    I investigated ecological and phylogenetic correlates to body size variations in 10 taxa of extant Indriidae (Indri, Avahi, and Propithecus). I also tested for phylogenetic niche conservatism as a model for the evolution of indriid body size. Phylogenetic niche conservatism refers to the shared attributes that related taxa have acquired because they tend to have occupied similar niches during their evolutionary history. I collected species-specific data on body mass, climate, density, and chemical properties of food items from the literature. I used 2 phylogenies in independent contrasts methods to control for phylogenetic relationships (Indri and Propithecus as sister taxa vs. Indri basal taxa to all indriids). Multivariate models indicated that lemur density and resource quality are the strongest ecological correlates to indriid body size variations. Partitioning methods revealed that 52.4–67 % of indriid body size variation is explained by phylogenetic niche conservation. Thus, indriid body size variations may be the result of stabilizing selection. Though it is possible to identify constraints on lower than average body size, there are few data on selection against larger than average body size in indriids. Large body size in subfossil lemurs further complicates identification of constraints on larger than average body size in extant indriids. Researchers using independent contrast methods to control for phylogeny should be aware that some ecology-phenotype relationships are best explained as the result of the synergistic effects of ecology and phylogeny. KEY WORDS: density; food quality; Indriidae; phylogenetic niche conservation; stabilizing selection