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Emmanuel J P Douzery - One of the best experts on this subject based on the ideXlab platform.
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What is a Suiforme (Artiodactyla)?: Contribution of Cranioskeletal and Mitochondrial DNA Data
Molecular Phylogenetics and Evolution, 1998Co-Authors: Claudine Montgelard, Stephane Ducrocq, Emmanuel J P DouzeryAbstract:Abstract Suiformes (Artiodactyla) traditionally includes three families: Suidae, Tayassuidae, and Hippopotamidae but the monophyly of this suborder has recently been questioned from molecular data. A maximum parsimony analysis of molecular, morphological, and combined data was performed on the same set of taxa including representatives of the three Artiodactyla suborders (Suiformes, Ruminantia, and Tylopoda) and Perissodactyla as outgroup. Mitochondrial (cytochromeband 12S rRNA) sequence comparisons support the monophyly of Suina (Suidae and Tayassuidae) and Ancodonta (Hippopotamidae) but not the monophyly of Suiformes. Inversely, our preliminary morphological analysis supports the monophyly of Suiformes whereas relationships among the three families are not resolved. The combined data set does not resolve the relationships between Suina, Ancodonta, and Ruminantia. These results are discussed in relation to morphological characters and paleontological data. Some improvements are suggested to clarify the morphological definition of Suiformes and relationships among them.
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new phylogenetic perspectives on the cervidae Artiodactyla are provided by the mitochondrial cytochrome b gene
Proceedings of The Royal Society B: Biological Sciences, 1998Co-Authors: Ettore Randi, Nadia Mucci, M Pierpaoli, Emmanuel J P DouzeryAbstract:The entire mitochondrial cytochrome b (cyt b) gene was compared for 11 species of the artiodactyl family Cervidae, representing all living subfamilies, i.e. the antlered Cervinae (Cervus elaphus, C...
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phylogenetic relationships of artiodactyls and cetaceans as deduced from the comparison of cytochrome b and 12s rrna mitochondrial sequences
Molecular Biology and Evolution, 1997Co-Authors: Claudine Montgelard, Francois Catzeflis, Emmanuel J P DouzeryAbstract:: A data set of complete mitochondrial cytochrome b and 12S rDNA sequences is presented here for 17 representatives of Artiodactyla and Cetacea, together with potential outgroups (two Perissodactyla, two Carnivora, two Tethytheria, four Rodentia, and two Marsupialia). We include seven sequences not previously published from Hippopotamidae (Ancodonta) and Camelidae (Tylopoda), yielding a total of nearly 2.1 kb for both genes combined. Distance and parsimony analyses of each gene indicate that 11 clades are well supported, including the artiodactyl taxa Pecora, Ruminantia (with low 12S rRNA support), Tylopoda, Suina, and Ancodonta, as well as Cetacea, Perissodactyla, Carnivora, Tethytheria, Muridae, and Caviomorpha. Neither the cytochrome b nor the 12S rDNA genes resolve the relationships between these major clades. The combined analysis of the two genes suggests a monophyletic Cetacea +Artiodactyla clade (defined as "CetArtiodactyla"), whereas Perissodactyla, Carnivora, and Tethytheria fall outside this clade. Perissodactyla could represent the sister taxon of CetArtiodactyla, as deduced from resampling studies among outgroup lineages. CetArtiodactyla includes five major lineages: Ruminantia, Tylopoda, Suina, Ancodonta, and Cetacea, among which the phylogenetic relationships are not resolved. Thus, Suiformes do not appear to be monophyletic, justifying their split into the Suina and Ancodonta infraorders. An association between Cetacea and Hippopotamidae is supported by the cytochrome b gene but not by the 12S rRNA gene. Calculation of divergence dates suggests that the CetArtiodactyla could have diverged from other Ferungulata about 60 MYA.
J L Williams - One of the best experts on this subject based on the ideXlab platform.
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bovine microsatellite loci are highly conserved in red deer cervus elaphus sika deer cervus nippon and soay sheep ovis aries
Animal Genetics, 1998Co-Authors: Jon Slate, David W Coltman, Simon J Goodman, I Maclean, Josephine M Pemberton, J L WilliamsAbstract:We tested 174 bovine microsatellite primer pairs for use in a primitive breed of sheep and two species of deer. Of 173 markers, 127 (73.4%) gave a product in Soay sheep (Ovis aries) of which 54 (42.5%) were polymorphic. One hundred and twenty-nine of 174 (74.1%) markers gave a product in red deer (Cervus elaphus) of which 72 (55.8%) were polymorphic. In sika deer (Cervus nippon) 126 of 171 (73.7%) microsatellite primers gave a product with 47 (37.3%) polymorphic. The proportion of bovine microsatellite loci conserved across artiodactyl species was significantly greater in this study than previously reported. Reasons for this high degree of microsatellite conservation are discussed. We suggest that a high resolution comparative map of the artiodactyls can be constructed using microsatellites.
Ulfur Arnason - One of the best experts on this subject based on the ideXlab platform.
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The mitochondrial genome of the sperm whale and a new molecular reference for estimating eutherian divergence dates
Journal of Molecular Evolution, 2000Co-Authors: Ulfur Arnason, B Ursing, Anette Gullberg, Solveig Gretarsdottir, Axel JankeAbstract:Extant cetaceans are systematically divided into two suborders: Mysticeti (baleen whales) and Odontoceti (toothed whales). In this study, we have sequenced the complete mitochondrial (mt) genome of an odontocete, the sperm whale (Physeter macrocephalus), and included it in phylogenetic analyses together with the previously sequenced complete mtDNAs of two mysticetes (the fin and blue whales) and a number of other mammals, including five artiodactyls (the hippopotamus, cow, sheep, alpaca, and pig). The most strongly supported cetartiodactyl relationship was: outgroup,((pig, al- paca),((cow, sheep),(hippopotamus,(sperm whale,(ba- leen whales))))). As in previous analyses of complete mtDNAs, the sister-group relationship between the hippopotamus and the whales received strong support, making both Artiodactyla and Suiformes (pigs, peccaries, and hippopotamuses) paraphyletic. In addition, the analyses identified a sister-group relationship between Suina (the pig) and Tylopoda (the alpaca), although this relationship was not strongly supported. The paleontological records of both mysticetes and odontocetes extend into the Oligocene, suggesting that the mysticete and odontocete lineages diverged 32–34 million years before present (MYBP). Use of this divergence date and the complete mtDNAs of the sperm whale and the two baleen whales allowed the establishment of a new molecular reference, O/M-33, for dating other eutherian divergences. There was a general consistency between O/M-33 and the two previously established eutherian references, A/C-60 and E/R-50. Cetacean (whale) origin, i.e., the divergence between the hippopotamus and the cetaceans, was dated to ≈55 MYBP, while basal artiodactyl divergences were dated to?65 MYBP. Molecular estimates of Tertiary eutherian divergences were consistent with the fossil record.
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the complete mitochondrial dna sequence of the greater indian rhinoceros rhinoceros unicornis and the phylogenetic relationship among carnivora perissodactyla and Artiodactyla cetacea
Molecular Biology and Evolution, 1996Co-Authors: Xiufeng Xu, Axel Janke, Ulfur ArnasonAbstract:The sequence (16,829 nt) of the complete mitochondrial genome of the greater Indian rhinoceros, Rhinoceros unicornis, was determined. Like other perissodactyls studied (horse and donkey) the rhinoceros demonstrates length variation (heteroplasmy) associated with different numbers of repetitive motifs in the control region. The 16,829-nt variety of the molecule includes 36 identical control region motifs. The evolution of individual peptide-coding genes was examined by comparison with a distantly related perissodactyl, the horse, and the relationships among the orders Carnivora, Perissodactyla, and Artiodactyla (+ Cetacea) were examined on the basis of concatenated sequences of 12 mitochondrial peptide-coding genes. The phylogenetic analyses grouped Carnivora, Perissodactyla, and Artiodactyla (+ Cetacea) into a superordinal clade and within this clade a sister group relationship was recognized between Carnivora and Perissodactyla to the exclusion of Artiodactyla (+ Cetacea). On the basis of the molecular difference between the rhinoceros and the horse and by applying as a reference the Artiodactyl/Cetacean divergence set at 60 million years ago (MYA), the evolutionary divergence between the families Rhinocerotidae and Equidae was dated to approximate to 50 MYA. (Less)
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cytochrome b nucleotide sequences and the identification of five primary lineages of extant cetaceans
Molecular Biology and Evolution, 1996Co-Authors: Ulfur Arnason, Anette GullbergAbstract:: Relationships among and within baleen and toothed whales were examined using the complete sequence of the mitochondrial cytochrome b gene. Based on parsimony analyses of conservative nucleotide substitutions, five primary evolutionary lineages of extant cetaceans were identified, one represented by baleen whales (Mysticeti) and four represented by odontocetes (toothed whales). Based on the most comprehensive representation of taxa, both cetaceans and artiodactyls, the most parsimonious relationship among the five lineages is (Mysticeti, Odontoceti (Platanistoidea (Physeteroidea (Ziphioidea (Delphinida))))). This relationship, however, is labile and sensitive to ingroup representation and the choice of outgroup. The short nodes among the five cetacean lineages suggest that the divergence among these lineages occurred over a narrow time period, a finding consistent with the limited fossil evidence that indicates a major cetacean radiation 30-34 Mya. The level of divergence among the five cetacean lineages, and that seen between cetaceans and artiodactyls, suggests that cetaceans and artiodactyls had a common ancestor approximately 60 Mya.
Axel Janke - One of the best experts on this subject based on the ideXlab platform.
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The mitochondrial genome of the sperm whale and a new molecular reference for estimating eutherian divergence dates
Journal of Molecular Evolution, 2000Co-Authors: Ulfur Arnason, B Ursing, Anette Gullberg, Solveig Gretarsdottir, Axel JankeAbstract:Extant cetaceans are systematically divided into two suborders: Mysticeti (baleen whales) and Odontoceti (toothed whales). In this study, we have sequenced the complete mitochondrial (mt) genome of an odontocete, the sperm whale (Physeter macrocephalus), and included it in phylogenetic analyses together with the previously sequenced complete mtDNAs of two mysticetes (the fin and blue whales) and a number of other mammals, including five artiodactyls (the hippopotamus, cow, sheep, alpaca, and pig). The most strongly supported cetartiodactyl relationship was: outgroup,((pig, al- paca),((cow, sheep),(hippopotamus,(sperm whale,(ba- leen whales))))). As in previous analyses of complete mtDNAs, the sister-group relationship between the hippopotamus and the whales received strong support, making both Artiodactyla and Suiformes (pigs, peccaries, and hippopotamuses) paraphyletic. In addition, the analyses identified a sister-group relationship between Suina (the pig) and Tylopoda (the alpaca), although this relationship was not strongly supported. The paleontological records of both mysticetes and odontocetes extend into the Oligocene, suggesting that the mysticete and odontocete lineages diverged 32–34 million years before present (MYBP). Use of this divergence date and the complete mtDNAs of the sperm whale and the two baleen whales allowed the establishment of a new molecular reference, O/M-33, for dating other eutherian divergences. There was a general consistency between O/M-33 and the two previously established eutherian references, A/C-60 and E/R-50. Cetacean (whale) origin, i.e., the divergence between the hippopotamus and the cetaceans, was dated to ≈55 MYBP, while basal artiodactyl divergences were dated to?65 MYBP. Molecular estimates of Tertiary eutherian divergences were consistent with the fossil record.
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the complete mitochondrial dna sequence of the greater indian rhinoceros rhinoceros unicornis and the phylogenetic relationship among carnivora perissodactyla and Artiodactyla cetacea
Molecular Biology and Evolution, 1996Co-Authors: Xiufeng Xu, Axel Janke, Ulfur ArnasonAbstract:The sequence (16,829 nt) of the complete mitochondrial genome of the greater Indian rhinoceros, Rhinoceros unicornis, was determined. Like other perissodactyls studied (horse and donkey) the rhinoceros demonstrates length variation (heteroplasmy) associated with different numbers of repetitive motifs in the control region. The 16,829-nt variety of the molecule includes 36 identical control region motifs. The evolution of individual peptide-coding genes was examined by comparison with a distantly related perissodactyl, the horse, and the relationships among the orders Carnivora, Perissodactyla, and Artiodactyla (+ Cetacea) were examined on the basis of concatenated sequences of 12 mitochondrial peptide-coding genes. The phylogenetic analyses grouped Carnivora, Perissodactyla, and Artiodactyla (+ Cetacea) into a superordinal clade and within this clade a sister group relationship was recognized between Carnivora and Perissodactyla to the exclusion of Artiodactyla (+ Cetacea). On the basis of the molecular difference between the rhinoceros and the horse and by applying as a reference the Artiodactyl/Cetacean divergence set at 60 million years ago (MYA), the evolutionary divergence between the families Rhinocerotidae and Equidae was dated to approximate to 50 MYA. (Less)
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phylogenetic relationships among eutherian orders estimated from inferred sequences of mitochondrial proteins instability of a tree based on a single gene
Journal of Molecular Evolution, 1994Co-Authors: Jun Adachi, Svante Pääbo, Axel Janke, Masami HasegawaAbstract:The phylogenetic relationships among Primates (human), Artiodactyla (cow), Cetacea (whale), Carnivora (seal), and Rodentia (mouse and rat) were estimated from the inferred amino acid sequences of the mitochondrial genomes using Marsupialia (opossum), Aves (chicken), and Amphibia (Xenopus) as an outgroup. The overall evidence of the maximum likelihood analysis suggests that Rodentia is an outgroup to the other four eutherian orders and that Cetacea and Artiodactyla form a clade with Carnivora as a sister taxon irrespective of the assumed model for amino acid substitutions. Although there remains an uncertainty concerning the relation among Artiodactyla, Cetacea, and Carnivora, the existence of a clade formed by these three orders and the outgroup status of Rodentia to the other eutherian orders seems to be firmly established. However, analyses of individual genes do not necessarily conform to this conclusion, and some of the genes reject the putatively correct tree with nearly 5% significance. Although this discrepancy can be due to convergent or parallel evolution in the specific genes, it was pointed out that, even without a particular reason, such a discrepancy can occur in 5% of the cases if the branching among the orders in question occurred within a short period. Due to uncertainty about the assumed model underlying the phylogenetic inference, this can occur even more frequently. This demonstrates the importance of analyzing enough sequences to avoid the danger of concluding an erroneous tree.
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the marsupial mitochondrial genome and the evolution of placental mammals
Genetics, 1994Co-Authors: Axel Janke, Gertraud Feldmaierfuchs, W K Thomas, Arndt Von Haeseler, Svante PääboAbstract:The entire nucleotide sequence of the mitochondrial genome of the American opossum, Didelphis virginiana, was determined. Two major features distinguish this genome from those of other mammals. First, five tRNA genes around the origin of light strand replication are rearranged. Second, the anticodon of tRNA(Asp) is posttranscriptionally changed by an RNA editing process such that its coding capacity is altered. When the complete protein-coding region of the mitochondrial genome is used as an outgroup for placental mammals it can be shown that rodents represent an earlier branch among placental mammals than primates and artiodactyls and that artiodactyls share a common ancestor with carnivores. The overall rates of evolution of most of the mitochondrial genome of placentals are clock-like. Furthermore, the data indicate that the lineages leading to the mouse and rat may have diverged from each other as much as 35 million years ago.
Emmanuel Gilissen - One of the best experts on this subject based on the ideXlab platform.
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virtual endocranial cast of earliest eocene diacodexis Artiodactyla mammalia and morphological diversity of early artiodactyl brains
Proceedings of The Royal Society B: Biological Sciences, 2012Co-Authors: Maeva J Orliac, Emmanuel GilissenAbstract:The study of brain evolution, particularly that of the neocortex, is of primary interest because it directly relates to how behavioural variations arose both between and within mammalian groups. Artiodactyla is one of the most diverse mammalian clades. However, the first 10 Myr of their brain evolution has remained undocumented so far. Here, we used high-resolution X-ray computed tomography to investigate the endocranial cast of Diacodexis ilicis of earliest Eocene age. Its virtual reconstruction provides unprecedented access to both metric parameters and fine anatomy of the most complete endocast of the earliest artiodactyl. This picture is assessed in a broad comparative context by reconstructing endocasts of 14 other Early and Middle Eocene representatives of basal artiodactyls, allowing the tracking of the neocortical structure of artiodactyls back to its simplest pattern. We show that the earliest artiodactyls share a simple neocortical pattern, so far never observed in other ungulates, with an almond-shaped gyrus instead of parallel sulci as previously hypothesized. Our results demonstrate that artiodactyls experienced a tardy pulse of encephalization during the Late Neogene, well after the onset of cortical complexity increase. Comparisons with Eocene perissodactyls show that the latter reached a high level of cortical complexity earlier than the artiodactyls.
