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At least 19 recordsLinked to original sources
PubMed1990

Molecular phylogeny of Rodentia, Lagomorpha, Primates, Artiodactyla, and Carnivora and molecular clocks.

Phylogenetic analysis of DNA sequences from primates, rodents, lagomorphs, artiodactyls, carnivores, and birds strongly suggests that the order Rodentia is an outgroup to the other four mammalian orders and that Artiodactyla and Carnivora belong to a superordinal clade. Further, there is strong evidence against the Glires concept, which unites Lagomorpha and Rodentia. The radiation among Lagomorpha, Primates, and Artiodactyla--Carnivora is very bush-like, but there is some evidence that Lagomorpha has branched off first. Thus, the branching sequence for these five orders of mammals seems to be Rodentia, Lagomorpha, Primates, Artiodactyla, and Carnivora. The branching date for Rodentia could be as early as 100 million years ago. The rate of nucleotide substitution in the rodent lineage is shown to be at least 1.5 times higher than those in the other four mammalian lineages.

Animals↗
PubMed1996

Phylogenetic position of the order Lagomorpha (rabbits, hares and allies)

Ever since they have been classified as ruminants in the Old Testament (Leviticus 11:6, Deuteronomy 14:7) and equated with hyraxes in the vulgate Latin translation, rabbits and their relatives (order Lagomorpha) have frequently experienced radical changes in taxonomic rank. By using 91 orthologous protein sequences, we have attempted to answer the classical question "What, if anything, is a rabbit?". Here we show that Lagomorpha is significantly more closely related to Primates and Scandentia (tree shrews) than it is to rodents. This newly determined phylogenetic position invalidates the superordinal taxon Glires (Lagomorpha + Rodentia), and indicates that the morphological 'synapomorphies' previously used to cluster rodents and lagomorphs into Glires, may actually represent symplesiomorphies or homoplasies that are of no phylogenetic value. This raises the possibility that the ancestral eutherian morphotype may have possessed many rodent-like morphological characters.

Animals↗
PubMedDate not supplied

[Nematodirinae (Nematoda) from Ruminants and from lagomorpha. (author's transl)].

Study of eight species of Nematodirinae with special emphasis on their synlophe: Nematodirus filicollis (Rudolphi, 1802), N. spathiger (Railliet, 1896). N. helvetianus May, 1920, N. battus Crofton & Thomas, 1951, N. tortuosus Tucker, 1942, Nematodirella dromedarii (May, 1920), Nematodiroides zembrae (Bernard, 1965) and Rauschia triangularis, type species of the new genus Rauschia. Furthermore, bibliographical data permit to know the structure of the synlophe in four other species. In each of these species the synlophe retains the primitive bilateral symmetry observed in the Molineidae; in species parasitic in Ruminants and Rodents, the synlophe shows non pronounced size gradient, nor a pronounced peculiar orientation of the tip of the crests. These last specialized characters are observed, on the contrary, in species parasitic in Lagomorpha. These latter show, starting from synlophes of the "Anoplostrongylinae"-type, various evolutionary essays; the most remarkable is an hypertrophy of the dorsal crests which leads at the end of the evolution, to a dextral coiling, the back of the animal being inside the spire: such a position appears unique in the superfamily. Rauschia gen. nov. (type species: R. triangularis) is created for species previously pertaining to Nematodirus parasite of Lagomorpha, and in which the synlophe, very complex, differs from the synlophe of the parasite of Ruminants. A dichotomic key of the six genera of Nematodirinae is proposed.

Animals↗
PubMed1999

Cytochrome b phylogeny of North American hares and jackrabbits (Lepus, lagomorpha) and the effects of saturation in outgroup taxa.

Jackrabbits and hares, members of the genus Lepus, comprise over half of the species within the family Leporidae (Lagomorpha). Despite their ecological importance, potential economic impact, and worldwide distribution, the evolution of hares and jackrabbits has been poorly studied. We provide an initial phylogenetic framework for jackrabbits and hares so that explicit hypotheses about their evolution can be developed and tested. To this end, we have collected DNA sequence data from a 702-bp region of the mitochondrial cytochrome b gene and reconstructed the evolutionary history (via parsimony, neighbor joining, and maximum likelihood) of 11 species of Lepus, focusing on North American taxa. Due to problems of saturation, induced by multiple substitutions, at synonymous coding positions between the ingroup taxa and the outgroups (Oryctolagus and Sylvilagus), both rooted and unrooted trees were examined. Variation in tree topologies generated by different reconstruction methods was observed in analyses including the outgroups, but not in the analyses of unrooted ingroup networks. Apparently, substitutional saturation hindered the analyses when outgroups were considered. The trees based on the cytochrome b data indicate that the taxonomic status of some species needs to be reassessed and that species of Lepus within North America do not form a monophyletic entity.

Animals↗
PubMedDate not supplied

Identification of new medium reiteration frequency repeats in the genomes of Primates, Rodentia and Lagomorpha.

We report eleven new families of MEdium Reiteration frequency (MER) interspersed repeats in the genomes of Primates, Rodentia, and Lagomorpha. Two families of the human repeats, MER 46 and MER 47, represent non-autonomous DNA transposons. These sequences are flanked by TA target site duplications and have terminal inverted repeats (TIRs) similar to TIRs of DNA transposons. The sequences of five other families of repeats, MER41, MER48, MER50, MER51, and RMER3, resemble long terminal repeats of retroviruses. A potential involvement of some of the reported MER repeats in the regulation of transcription and genetic rearrangements is suggested. Age estimations place the origin of most MER repeats at the time of decline in MIR (Mammalian-wide Interspersed Repeats) retroposition and before the origin of the Alu family.

Animals↗
PubMed1990

The Syphaciinae (Oxyuridae, Nematoda) parasitic in rodents and lagomorpha. Numerical taxonomy. Cladistic analysis of evolution.

Two different methods are successively used for the systematic study of the Syphaciinae, a parasitic group of pin-worms specific for the Rodents and Lagomorpha. The statistical method permits to build a "phenetic classification"; the cladistic method permits to build a "phylogenetic classification". The classification finally proposed is principally found on the results of the morphological study of the parasites, but has also in view the integration of all available data concerning the biology, the biogeography and the phylogeny of the hosts.

Animals↗
PubMed2005

Coevolution and biogeography among Nematodirinae (Nematoda: Trichostrongylina) Lagomorpha and Artiodactyla (Mammalia): exploring determinants of history and structure for the northern fauna across the holarctic.

Nematodes of the subfamily Nematodirinae are characteristic components of a Holarctic fauna. The topology of a generic-level phylogenetic hypothesis, patterns of diversity, and geographic distributions for respective nematode taxa in conjunction with data for host occurrence are consistent with primary distributions determined across Beringia for species of Murielus, Rauschia, Nematodirus, and Nematodirella. Ancestral hosts are represented by Lagomorpha, with evidence for a minimum of 1 host-switching-event and subsequent radiation in the Artiodactyla. Diversification may reflect vicariance of respective faunas along with episodic or cyclical range expansion and isolation across Beringia during the late Tertiary and Quaternary. Secondarily, species of Nematodirus attained a distribution in the Neotropical region with minimal diversification of an endemic fauna represented by Nematodirus molini among tayassuids, Nematodirus lamae among camelids and Nematodirus urichi in cervids during the Pleistocene. Nematodirines are a core component of an Arctic-Boreal fauna of zooparasitic nematodes (defined by latitude and altitude) adapted to transmission in extreme environments characterized by seasonally low temperatures and varying degrees of desiccation. The history and distribution of this fauna is examined in the context of biotic and abiotic determinants for geographic colonization and host switching with an exploration of predicted responses of complex host-parasite systems to ecological perturbation under a regime of global climate change.

Animals↗
PubMed1986

A Golgi study of the sixth layer of the cerebral cortex. I. The lissencephalic brain of Rodentia, Lagomorpha, Insectivora and Chiroptera.

A study of the morphological characteristics of the neurons in layer VI of the cerebral cortex was carried out using the rapid Golgi method in several lissencephalic species including Rodentia (rat, mouse, vole (Microtus agrestis) and hamster), Lagomorpha (rabbit), Insectivora (hedgehog) and in the Chiroptera the dwarf bat (Pipistrellus pipistrellus). There was a basic uniformity in the structure of the sixth layer. Main neuronal types in lamina VIa were large pyramidal neurons, triangular or atypical pyramidal cells, multiapical pyramidal neurons, inverted pyramids, fusiform neurons, Martinotti cells and bi-tufted cells. Main neuronal types in lamina VIb were medium sized, flattened pyramids, large and small horizontal neurons, horizontal pyramidal cells, fan shaped neurons and multipolar spinous neurons with long descending axons. Sparsely spinous and spine-free multipolar neurons with short axons were present in the two laminae of layer VI, but sparsely spinous neurons with axons similar to those found in basket cells of other layers of the cortex were observed mainly in lamina VIa. Neuronal subsystems were tentatively classified on the basis of the course of the axons. Pyramidal neurons, fusiform neurons, multiapical pyramidal cells, inverted pyramidal cells, fan shaped neurons and multipolar neurons with large descending axons were interpreted as being the main source of long projection and association connections. Large horizontal neurons were interpreted as possible ipsilateral association neurons because the horizontal course of the axons over long distances followed the boundary of the deeper region of the sixth layer. Three intracortical (association) subsystems were included. Axons of Martinotti cells and collateral ascending axons of pyramidal neurons (including multiapical pyramidal neurons) formed the ascending interlaminar fibrillary subsystem. Axons of small horizontal cells and horizontal collaterals of pyramidal neurons formed the horizontal intracortical subsystem. Sparsely spinous and spine-free multipolar neurons and bi-tufted cells were the main source of the local, non-horizontal fibrillary subsystem.

Anatomy, Comparative↗
PubMed1983

Histochemical localization and functional significance of carbonic anhydrase in the salivary glands of some rodents and lagomorpha: an optical and electron microscopical study.

An investigation was carried out by light and electron microscopy on the localization of the carbonic anhydrase enzyme in the submandibular and sublingual glands of some rodents and lagomorpha. By means of the cobalt-bicarbonate technique, it was demonstrated that in the submandibular glands the carbonic anhydrase activity is more intense in the terminal tracts, and that in the sublingual glands the enzyme activity is present in an equal degree in the terminal tracts and in the intralobular ducts. The results obtained are compared to those of other authors, and conjectures are made as to the functional significance of the carbonic anhydrase activity in the salivary glands.

Animals↗
PubMed1984

Variability and ultrastructural histochemical localization of sulphates in the salivary glands of rodents and Lagomorpha.

Stainings were effected on an ultrastructural histochemical level to localize sulphomucins in the submandibular and sublingual glands of growing mice and rabbits. Sulphates behave in an entirely different way in the salivary glands of Lagomorpha and in those of Rodents. In growing rabbits sulphates can be demonstrated in both glands; at maturity they can be demonstrated only in the sublingual gland and no longer in the submandibular gland. In the salivary glands of Rodents, sulphates cannot be demonstrated histochemically in new born subjects or in adults. The histochemical results are compared to the biochemical ones, and discrepancies, where present, are discussed.

Aging↗
PubMed1974

Comparative study of erythrocyte glycolytic enzymes in man and in two species of Lagomorphae. (Ochotona rufescens rufescens and Oryctolagus cuniculus).

The authors made a comparative study of red cell enzyme glycolysis in man and in two species of Lagomorphae, the pika and the rabbit. The activities of the 12 enzymes of Embden-Meyerhoff pathway and of the two dehydrogenases of pentose shunt (glucose-6-phosphate dehydrogenase and 6-phosphogluconate dehydrogenase) were determined. Phosphoglycerate kinase and pyruvate kinase showed quite similar activities in pika erythrocytes and in erythrocytes from human umbilical cord. The levels of these enzymes differed significantly in the pika and in the rabbit. No differences were noted between pyruvate kinases from the rabbit and the neonatal man. The other activities gave values either identical to those found in the adult man or intermediate between the adult and the neonatal man. In the rabbit the levels of glycolitic enzymes were generally lower than in the pika except for lactate dehydrogenase and glycose-6-phosphate dehydrogenase. Some characteristics of erythrocyte metabolism specific to the pika may account for the differences observed in this species. The influence of red cell age cannot explain the variations observed for no significant reticulocytosis was observed in the circulating blood. The percentages found in the pika and the rabbit were essentially identical at determination.

Adult↗
PubMed1992

Role of Lagomorpha in the wild cycle of Rickettsia conorii in Salamanca (Spain).

In an endemic zone for Mediterranean spotted fever levels of antibodies to R. conorii were evaluated in serum samples from wild rabbits (Orytolagus cuniculus) and hares (Lepus granatensis) using an indirect microimmunofluorescence antibody test. The results of the study show that the wild rabbit may carry out in this area an important function in the maintenance of R. conorii in nature.

Animals↗
PubMed1999

Multiple substitutions affect the phylogenetic utility of cytochrome b and 12S rDNA data: examining a rapid radiation in leporid (Lagomorpha) evolution.

Partial sequences of two mitochondrial genes, the 12S ribosomal gene (739 bp) and the cytochrome b gene (672 bp), were analyzed in hopes of reconstructing the evolutionary relationships of 11 leporid species, representative of seven genera. However, partial cytochrome b sequences were of little phylogenetic value in this study. A suite of pairwise comparisons between taxa revealed that at the intergeneric level, the cytochrome b gene is saturated at synonymous coding positions due to multiple substitution events. Furthermore, variation at the nonsynonymous positions is limited, rendering the cytochrome b gene of little phylogenetic value for assessing the relationships between leporid genera. If the cytochrome b data are analyzed without accounting for these two classes of nucleotides (i.e., synonymous and nonsynonymous sites), one may incorrectly conclude that signal exists in the cytochrome b data. The mitochondrial 12S rRNA gene, on the other hand, has not experienced excessive saturation at either stem or loop positions. Phylogenies reconstructed from the 12S rDNA data support hypotheses based on fossil evidence that African rock rabbits (Pronolagus) are outside of the main leporid stock and that leporids experienced a rapid radiation. However, the molecular data suggest that this radiation event occurred in the mid-Miocene several millions of years earlier than the Pleistocene dates suggested by paleontological evidence.

Animals↗
PubMed1982

Uteroglobin-like antigens in species of Lagomorpha.

1. Uteroglobin-like antigens were found in the lung and uterus of the hare (Lepus) and the pika (Ochotona). These antigens presented an immunoreactivity indistinguishable from that of rabbit uteroglobin, as determined by radioimmunoassay. 2. The molecular weight and the subunit composition of these antigens were similar to those of rabbit uteroglobin as analyzed by SDS gel-electrophoresis. 3. Similar amounts of uteroglobin-like immunoreactivity were found in the respective lungs and uteri of hare and rabbit whereas the concentration of immunoreactivity in the pika organs was several-fold lower.

Animals↗
PubMed2001

Mitochondrial cytochrome b gene sequence diversity in the Korean hare, Lepus coreanus Thomas (Mammalia, Lagomorpha).

Partial sequences of the mitochondrial cytochrome b gene of the Korean hare (Lepus coreanus) were analyzed to determine the degree of genetic diversity. Nine haplotypes were observed, and the maximum Tamura-Nei nucleotide distance among them was 2.8%, indicating that genetic diversity of L. coreanus is moderate. In order to clarify the Korean hare's taxonomic status and relationship with the Manchurian hare (L. mandshuricus) and the Chinese hare (L. sinensis), these nine haplotypes of the Korean hare were compared with 13 haplotypes from five other species of eastern Asian Lepus including L. mandshuricus and L. sinensis. The Korean hare was distinct in its cytochrome b gene, and it is confirmed that L. coreanus is a valid species, as noted by Jones and Johnson (1965, Univ. Kansas Publ. (Mus. Nat. Hist.) 16:357). Further analyses of mtDNA cytochrome b gene with additional specimens of L. coreanus from North Korea and other species of Lepus from eastern Asia are needed to clarify the taxonomic status of the divergent mtDNA clades of L. mandshuricus and L. sinensis.

Animals↗
PubMed1983

Protein variation and its systematic implications for the South African Leporidae (Mammalia:Lagomorpha).

Analysis of 9 genetic loci by horizontal starch gel electrophoresis was performed on 203 specimens of South African representatives of the leporid genera Lepus and Pronolagus. Three loci were found to be polymorphic within samples of the various species of both genera: transferrin (Tf-I), esterase-1 (Es-I) and esterase-2 (Es-II). Only one system, carbonic anhydrase (CA-I), proved useful in species identification, this being restricted to the genus Lepus. Based on this system all Lepus specimens analysed would be assigned to one of two groups corresponding to the species L. capensis and L. saxatilis.

Animals↗
PubMed2005

Stem Lagomorpha and the antiquity of Glires.

We describe several fossils referable to Gomphos elkema from deposits close to the Paleocene-Eocene boundary at Tsagan Khushu, Mongolia. Gomphos shares a suite of cranioskeletal characters with extant rabbits, hares, and pikas but retains a primitive dentition and jaw compared to its modern relatives. Phylogenetic analysis supports the position of Gomphos as a stem lagomorph and excludes Cretaceous taxa from the crown radiation of placental mammals. Our results support the hypothesis that rodents and lagomorphs radiated during the Cenozoic and diverged from other placental mammals close to the Cretaceous-Tertiary boundary.

Animals↗