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John A Finarelli - One of the best experts on this subject based on the ideXlab platform.
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Diversification histories for North American and Eurasian carnivorans
Biological Journal of the Linnean Society, 2016Co-Authors: John A Finarelli, Lee Hsiang LiowAbstract:The evolutionary processes that formed present-day biological diversity can be inferred through modelling past rates of extinction and origination from observations in the fossil record. We analyzed observations of over 5800 records from North America and Eurasia for 972 species in the mammalian order Carnivora. Using these records of carnivoran fossils, we estimated extinction, speciation and net diversification, while simultaneously estimating sampling probability, for the past 28 Myr. While global carnivoran diversification through the Neogene showed a pattern of surprisingly stability, diversification dynamics differ considerably between North America and Eurasia. This is particularly evident in the interval from 9 to 8 Mya, in which there is a pronounced peak of positive diversification in Eurasia that is not observed in the North American record, and from 6 to 5 Mya, in which North America experienced high rates of positive diversification, while Eurasia experienced significantly negative diversification. Our results indicate that North American members of the dogs, bears and amphicyonids, as well as other basal members of the Caniformia have lower rates of average net diversification than their counterparts in Eurasia, due to lower rates of speciation. However, average rates net diversification and their components are not distinguishable among other subclades of carnivorans in the on the two continents. In fact, most carnivoran subclades do not have significantly different estimates of average net rates of diversification.
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over 20 million years A dynamic global equilibrium in carnivoran diversification
2014Co-Authors: Lee Hsiang Liow, John A FinarelliAbstract:Cite this article: Liow LH, Finarelli JA. 2014A dynamic global equilibrium in carnivorandiversification over 20 million years.Proc. R. Soc. B 281: 20132312.http://dx.doi.org/10.1098/rspb.2013.2312Received: 5 September 2013Accepted: 20 December 2013Subject Areas:palaeontology, evolution, ecologyKeywords:capture–mark–recapture model, Caniformia,Feliformia, Pradel modelAuthor for correspondence:Lee Hsiang Liowe-mail: l.h.liow@ibv.uio.noElectronic supplementary material is availableat http://dx.doi.org/10.1098/rspb.2013.2312 orvia http://rspb.royalsocietypublishing.org.
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Brain-size evolution and sociality in Carnivora
Proceedings of the National Academy of Sciences of the United States of America, 2009Co-Authors: John A Finarelli, John J. FlynnAbstract:Increased encephalization, or larger brain volume relative to body mass, is a repeated theme in vertebrate evolution. Here we present an extensive sampling of relative brain sizes in fossil and extant taxa in the mammalian order Carnivora (cats, dogs, bears, weasels, and their relatives). By using Akaike Information Criterion model selection and endocranial volume and body mass data for 289 species (including 125 fossil taxa), we document clade-specific evolutionary transformations in encephalization allometries. These evolutionary transformations include multiple independent encephalization increases and decreases in addition to a remarkably static basal Carnivora allometry that characterizes much of the suborder Feliformia and some taxa in the suborder Caniformia across much of their evolutionary history, emphasizing that complex processes shaped the modern distribution of encephalization across Carnivora. This analysis also permits critical evaluation of the social brain hypothesis (SBH), which predicts a close association between sociality and increased encephalization. Previous analyses based on living species alone appeared to support the SBH with respect to Carnivora, but those results are entirely dependent on data from modern Canidae (dogs). Incorporation of fossil data further reveals that no association exists between sociality and encephalization across Carnivora and that support for sociality as a causal agent of encephalization increase disappears for this clade.
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testing hypotheses of the evolution of encephalization in the canidae carnivora mammalia
Paleobiology, 2008Co-Authors: John A FinarelliAbstract:Evolutionary trends observed over large clades have the potential to mask underlying trends that occur within their constituent subclades. A recent study of encephalization in the Caniformia (Carnivora, Mammalia) found evidence for an abrupt increase in median log-encephalization quotients (logEQs), indicating higher brain volume relative to body mass, at the end-Miocene, but gradual increase in the variance of logEQs. In this study, new endocranial volume estimates for fossil taxa in the well-sampled caniform subclade Canidae are reported. Using the encephalization data for the Canidae, hypotheses of evolution in encephalization allometries were tested with respect to canid phylogeny. The Akaike Information Criterion and likelihood ratios recovered support for a preferred hypothesis of the evolution of canid encephalization, which proposed two distinct allometric relationships: (1) a plesiomorphic grade of encephalization in the subfamilies Hesperocyoninae and Borophaginae and the paraphyletic canine genus Leptocyon , and (2) an apomorphic grade in the crown radiation of Caninae. This defines a shift in to higher encephalization, but without an associated change in the variance around the allometry. Increased canid encephalization coincides with a reorganization of the brain and the observed trend may reflect the evolution of complex social behavior in this clade.
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The evolution of encephalization in caniform carnivorans.
Evolution; international journal of organic evolution, 2007Co-Authors: John A Finarelli, John J. FlynnAbstract:A weighted-average model, which reliably estimates endocranial volume from three external measurements of the neurocranium of extant taxa in the mammalian order Carnivora, was tested for its applicability to fossil taxa by comparing model-estimated endocranial volumes to known endocast volumes. The model accurately reproduces endocast volumes for a wide array of fossil taxa across the crown radiation of the Carnivora, three stem carnivoramorphan taxa, and Pleistocene fossils of two extant species. Applying this model to fossil taxa without known endocast volumes expanded the sample of fossil taxa with estimated brain volumes in the carnivoran suborder Caniformia from 11 to 60 taxa. This then allowed a comprehensive assessment of the evolution of relative brain size across this clade. An allometry of brain volume to body mass was calculated on phylogenetically independent contrasts for the set of extant taxa, and from this, log-transformed encephalization quotients (logEQs) were calculated for all taxa, extant, and fossil. A series of Mann–Whitney tests demonstrated that the distributions of logEQs for taxa early in caniform evolutionary history possessed significantly lower median logEQs than extant taxa. Median logEQ showed a pronounced shift around the Miocene–Pliocene transition. Support tests, based on likelihood ratios, demonstrated that the variances of these distributions also were significantly lower than among modern taxa, but logEQ variance increased gradually through the history of the clade, not abruptly. Reconstructions of ancestral logEQs using weighted squared-change parsimony demonstrate that increased encephalization is observed across all major caniform clades (with the possible exception of skunks) and that these increases were achieved in parallel, although an “ancestor-descendant differencing” method could not rule out drift as a hypothesis. Peculiarities in the estimated logEQs for the extinct caniform family Amphicyonidae were also investigated; these unusual patterns are likely due to a unique allometry in scaling brain to body size in this single clade.
Gábor Á. Czirják - One of the best experts on this subject based on the ideXlab platform.
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species specific differences in toxoplasma gondii neospora caninum and besnoitia besnoiti seroprevalence in namibian wildlife
Parasites & Vectors, 2020Co-Authors: Anne Seltmann, Sonja K. Heinrich, Bettina Wachter, Ortwin Aschenborn, Susanne Thalwitzer, Gereon Schares, Gábor Á. CzirjákAbstract:Knowledge about parasitic infections is crucial information for animal health, particularly of free-ranging species that might come into contact with livestock and humans. We investigated the seroprevalence of three tissue-cyst-forming apicomplexan parasites (Toxoplasma gondii, Neospora caninum and Besnoitia besnoiti) in 506 individuals of 12 wildlife species in Namibia using in-house enzyme linked immunosorbent assays (indirect ELISAs applying purified antigens) for screening and immunoblots as confirmatory tests. We included six species of the suborder Feliformia, four species of the suborder Caniformia and two species of the suborder Ruminantia. For the two species for which we had most samples and life-history information, i.e. cheetahs (Acinonyx jubatus, n = 250) and leopards (Panthera pardus, n = 58), we investigated T. gondii seroprevalence in relation to age class, sex, sociality (solitary, mother-offspring group, independent sibling group, coalition group) and site (natural habitat vs farmland). All but one carnivore species (bat-eared fox Otocyon megalotis, n = 4) were seropositive to T. gondii, with a seroprevalence ranging from 52.4% (131/250) in cheetahs to 93.2% (55/59) in African lions (Panthera leo). We also detected antibodies to T. gondii in 10.0% (2/20) of blue wildebeest (Connochaetes taurinus). Adult cheetahs and leopards were more likely to be seropositive to T. gondii than subadult conspecifics, whereas seroprevalence did not vary with sex, sociality and site. Furthermore, we measured antibodies to N. caninum in 15.4% (2/13) of brown hyenas (Hyaena brunnea) and 2.6% (1/39) of black-backed jackals (Canis mesomelas). Antibodies to B. besnoiti were detected in 3.4% (2/59) of African lions and 20.0% (4/20) of blue wildebeest. Our results demonstrate that Namibian wildlife species were exposed to apicomplexan parasites at different prevalences, depending on parasite and host species. In addition to serological work, molecular work is also needed to better understand the sylvatic cycle and the clear role of wildlife in the epidemiology of these parasites in southern Africa.
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Species-specific differences in Toxoplasma gondii, Neospora caninum and Besnoitia besnoiti seroprevalence in Namibian wildlife
Parasites & Vectors, 2020Co-Authors: Anne Seltmann, Sonja K. Heinrich, Bettina Wachter, Susanne Thalwitzer, Gereon Schares, Ortwin H. K. Aschenborn, Gábor Á. CzirjákAbstract:Background Knowledge about parasitic infections is crucial information for animal health, particularly of free-ranging species that might come into contact with livestock and humans. Methods We investigated the seroprevalence of three tissue-cyst-forming apicomplexan parasites ( Toxoplasma gondii , Neospora caninum and Besnoitia besnoiti ) in 506 individuals of 12 wildlife species in Namibia using in-house enzyme linked immunosorbent assays (indirect ELISAs applying purified antigens) for screening and immunoblots as confirmatory tests. We included six species of the suborder Feliformia, four species of the suborder Caniformia and two species of the suborder Ruminantia. For the two species for which we had most samples and life-history information, i.e. cheetahs ( Acinonyx jubatus , n = 250) and leopards ( Panthera pardus , n = 58), we investigated T. gondii seroprevalence in relation to age class, sex, sociality (solitary, mother-offspring group, independent sibling group, coalition group) and site (natural habitat vs farmland). Results All but one carnivore species (bat-eared fox Otocyon megalotis , n = 4) were seropositive to T. gondii , with a seroprevalence ranging from 52.4% (131/250) in cheetahs to 93.2% (55/59) in African lions ( Panthera leo ). We also detected antibodies to T. gondii in 10.0% (2/20) of blue wildebeest ( Connochaetes taurinus ). Adult cheetahs and leopards were more likely to be seropositive to T. gondii than subadult conspecifics, whereas seroprevalence did not vary with sex, sociality and site. Furthermore, we measured antibodies to N. caninum in 15.4% (2/13) of brown hyenas ( Hyaena brunnea ) and 2.6% (1/39) of black-backed jackals ( Canis mesomelas ). Antibodies to B. besnoiti were detected in 3.4% (2/59) of African lions and 20.0% (4/20) of blue wildebeest. Conclusions Our results demonstrate that Namibian wildlife species were exposed to apicomplexan parasites at different prevalences, depending on parasite and host species. In addition to serological work, molecular work is also needed to better understand the sylvatic cycle and the clear role of wildlife in the epidemiology of these parasites in southern Africa.
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Feliform carnivores have a distinguished constitutive innate immune response.
Biology open, 2016Co-Authors: Sonja K. Heinrich, Bettina Wachter, Ortwin Aschenborn, Susanne Thalwitzer, Jörg Melzheimer, Heribert Hofer, Gábor Á. CzirjákAbstract:Determining the immunological phenotype of endangered and threatened populations is important to identify those vulnerable to novel pathogens. Among mammals, members of the order Carnivora are particularly threatened by diseases. We therefore examined the constitutive innate immune system, the first line of protection against invading microbes, of six free-ranging carnivore species; the black-backed jackal (Canis mesomelas), the brown hyena (Hyena brunnea), the caracal (Caracal caracal), the cheetah (Acinonyx jubatus), the leopard (Panthera pardus) and the lion (Panthera leo) using a bacterial killing assay. The differences in immune responses amongst the six species were independent of their foraging behaviour, body mass or social organisation but reflected their phylogenetic relatedness. The bacterial killing capacity of black-backed jackals, a member of the suborder Caniformia, followed the pattern established for a wide variety of vertebrates. In contrast, the five representatives of the suborder Feliformia demonstrated a killing capacity at least an order of magnitude higher than any species reported previously, with a particularly high capacity in caracals and cheetahs. Our results suggest that the immunocompetence of threatened felids such as the cheetah has been underestimated and its assessment ought to consider both innate and adaptive components of the immune system.
Takuya Kato - One of the best experts on this subject based on the ideXlab platform.
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Possible transmission of Sarcoptes scabiei between herbivorous Japanese serows and omnivorous Caniformia in Japan: a cryptic transmission and persistence?
Parasites & Vectors, 2019Co-Authors: Ryota Matsuyama, Toshihiro Yabusaki, Natsuko Senjyu, Tsukasa Okano, Minoru Baba, Tomoka Tsuji-matsukane, Mayumi Yokoyama, Nobuhide Kido, Teruki Kadosaka, Takuya KatoAbstract:Background Two transmission patterns of Sarcoptes scabiei in host mammal communities have been reported based on microsatellite-level genetic studies in the last two decades. While one involves restrictions among different host taxa, the other is associated with predator–prey interactions between different host taxa. In contrast to these observations, the present study reports a possible irregular case of transmission of S. scabiei between herbivorous Japanese serow and omnivorous Caniformia mammals in Japan, though under very weak predator–prey relationships. Methods DNA from 93 Sarcoptes mites isolated from omnivorous Caniformia (such as the domestic dog, raccoon dog, raccoon and Japanese marten), omnivorous Cetartiodactyla (wild boar) and herbivorous Cetartiodactyla (Japanese serow) in Japan were analyzed by amplifying nine microsatellite markers. Principal components analyses (PCA), Bayesian clustering analyses using STRUCTURE software, and phylogenetic analyses by constructing a NeighborNet network were applied to determine the genetic relationships among mites associated with host populations. Results In all the analyses, the genetic differentiation of Sarcoptes mites from wild boars and Japanese serows was observed. Conversely, considerably close genetic relationships were detected between Caniformia-derived and Japanese serow-derived mites. Because the predator–prey interactions between the omnivorous Caniformia and herbivorous Japanese serow are quite limited and epidemiological history shows at least a 10-year lag between the emergence of sarcoptic mange in Japanese serow and that in Caniformia, the transmission of S. scabiei from Caniformia to Japanese serow is highly suspected. Conclusions The close genetic relationships among mites beyond Host–taxon relationships and without obvious predator–prey interactions in Caniformia and Japanese serow deviate from previously reported S. scabiei transmission patterns. This type of cryptic relationship of S. scabiei populations may exist in local mammalian communities worldwide and become a risk factor for the conservation of the remnant and fragmented populations of wild mammals.
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Possible transmission of Sarcoptes scabiei between herbivorous Japanese serows and omnivorous Caniformia in Japan: a cryptic transmission and persistence?
Parasites & vectors, 2019Co-Authors: Ryota Matsuyama, Toshihiro Yabusaki, Natsuko Senjyu, Tsukasa Okano, Minoru Baba, Tomoka Tsuji-matsukane, Mayumi Yokoyama, Nobuhide Kido, Teruki Kadosaka, Takuya KatoAbstract:Background Two transmission patterns of Sarcoptes scabiei in host mammal communities have been reported based on microsatellite-level genetic studies in the last two decades. While one involves restrictions among different host taxa, the other is associated with predator–prey interactions between different host taxa. In contrast to these observations, the present study reports a possible irregular case of transmission of S. scabiei between herbivorous Japanese serow and omnivorous Caniformia mammals in Japan, though under very weak predator–prey relationships.
John J. Flynn - One of the best experts on this subject based on the ideXlab platform.
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Indarctos and other Caniformia fossils of G.E. Lewis’ YPM collection from the Siwaliks
Historical Biology, 2019Co-Authors: Qigao Jiangzuo, John J. FlynnAbstract:ABSTRACTMaterial of Indarctos and other Caniformia fossils from the Yale Peabody Museum G.E. Lewis Siwalik expedition collections from Pakistan and northern India are described herein. The M2 of a ...
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Brain-size evolution and sociality in Carnivora
Proceedings of the National Academy of Sciences of the United States of America, 2009Co-Authors: John A Finarelli, John J. FlynnAbstract:Increased encephalization, or larger brain volume relative to body mass, is a repeated theme in vertebrate evolution. Here we present an extensive sampling of relative brain sizes in fossil and extant taxa in the mammalian order Carnivora (cats, dogs, bears, weasels, and their relatives). By using Akaike Information Criterion model selection and endocranial volume and body mass data for 289 species (including 125 fossil taxa), we document clade-specific evolutionary transformations in encephalization allometries. These evolutionary transformations include multiple independent encephalization increases and decreases in addition to a remarkably static basal Carnivora allometry that characterizes much of the suborder Feliformia and some taxa in the suborder Caniformia across much of their evolutionary history, emphasizing that complex processes shaped the modern distribution of encephalization across Carnivora. This analysis also permits critical evaluation of the social brain hypothesis (SBH), which predicts a close association between sociality and increased encephalization. Previous analyses based on living species alone appeared to support the SBH with respect to Carnivora, but those results are entirely dependent on data from modern Canidae (dogs). Incorporation of fossil data further reveals that no association exists between sociality and encephalization across Carnivora and that support for sociality as a causal agent of encephalization increase disappears for this clade.
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The evolution of encephalization in caniform carnivorans.
Evolution; international journal of organic evolution, 2007Co-Authors: John A Finarelli, John J. FlynnAbstract:A weighted-average model, which reliably estimates endocranial volume from three external measurements of the neurocranium of extant taxa in the mammalian order Carnivora, was tested for its applicability to fossil taxa by comparing model-estimated endocranial volumes to known endocast volumes. The model accurately reproduces endocast volumes for a wide array of fossil taxa across the crown radiation of the Carnivora, three stem carnivoramorphan taxa, and Pleistocene fossils of two extant species. Applying this model to fossil taxa without known endocast volumes expanded the sample of fossil taxa with estimated brain volumes in the carnivoran suborder Caniformia from 11 to 60 taxa. This then allowed a comprehensive assessment of the evolution of relative brain size across this clade. An allometry of brain volume to body mass was calculated on phylogenetically independent contrasts for the set of extant taxa, and from this, log-transformed encephalization quotients (logEQs) were calculated for all taxa, extant, and fossil. A series of Mann–Whitney tests demonstrated that the distributions of logEQs for taxa early in caniform evolutionary history possessed significantly lower median logEQs than extant taxa. Median logEQ showed a pronounced shift around the Miocene–Pliocene transition. Support tests, based on likelihood ratios, demonstrated that the variances of these distributions also were significantly lower than among modern taxa, but logEQ variance increased gradually through the history of the clade, not abruptly. Reconstructions of ancestral logEQs using weighted squared-change parsimony demonstrate that increased encephalization is observed across all major caniform clades (with the possible exception of skunks) and that these increases were achieved in parallel, although an “ancestor-descendant differencing” method could not rule out drift as a hypothesis. Peculiarities in the estimated logEQs for the extinct caniform family Amphicyonidae were also investigated; these unusual patterns are likely due to a unique allometry in scaling brain to body size in this single clade.
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Ancestral State Reconstruction of Body Size in the Caniformia (Carnivora, Mammalia): The Effects of Incorporating Data from the Fossil Record
Systematic biology, 2006Co-Authors: John A Finarelli, John J. FlynnAbstract:A recent molecular phylogeny of the mammalian order Carnivora implied large body size as the ancestral condition for the caniform subclade Arctoidea using the distribution of species mean body sizes among living taxa. "Extant taxa-only" approaches such as these discount character state observations for fossil members of living clades and completely ignore data from extinct lineages. To more rigorously reconstruct body sizes of ancestral forms within the Caniformia, body size and first appearance data were collected for 149 extant and 367 extinct taxa. Body sizes were reconstructed for four ancestral nodes using weighted squared-change parsimony on log-transformed body mass data. Reconstructions based on extant taxa alone favored large body sizes (on the order of 10 to 50 kg) for the last common ancestors of both the Caniformia and Arctoidea. In contrast, reconstructions incorporating fossil data support small body sizes (< 5 kg) for the ancestors of those clades. When the temporal information associated with fossil data was discarded, body size reconstructions became ambiguous, demonstrating that incorporating both character state and temporal information from fossil taxa unambiguously supports a small ancestral body size, thereby falsifying hypotheses derived from extant taxa alone. Body size reconstructions for Caniformia, Arctoidea, and Musteloidea were not sensitive to potential errors introduced by uncertainty in the position of extinct lineages relative to the molecular topology, or to missing body size data for extinct members of an entire major clade (the aquatic Pinnipedia). Incorporating character state observations and temporal information from the fossil record into hypothesis testing has a significant impact on the ability to reconstruct ancestral characters and constrains the range of potential hypotheses of character evolution. Fossil data here provide the evidence to reliably document trends of both increasing and decreasing body size in several caniform clades. More generally, including fossils in such analyses incorporates evidence of directional trends, thereby yielding more reliable ancestral character state reconstructions.
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Molecular phylogeny of the carnivora (mammalia): assessing the impact of increased sampling on resolving enigmatic relationships.
Systematic biology, 2005Co-Authors: John J. Flynn, John A Finarelli, Sarah Zehr, Johnny Hsu, Michael A. NedbalAbstract:This study analyzed 76 species of Carnivora using a concatenated sequence of 6243 bp from six genes (nuclear TR-i-I, TBG, and IRBP; mitochondrial ND2, CYTB, and 12S rRNA), representing the most comprehensive sampling yet undertaken for reconstructing the phylogeny of this clade. Maximum parsimony and Bayesian methods were remarkably congruent in topologies observed and in nodal support measures. We recovered all of the higher level carnivoran clades that had been robustly supported in previous analyses (by analyses of morphological and molecular data), including the monophyly of Caniformia, Feliformia, Arctoidea, Pinnipedia, Musteloidea, Procyonidae + Mustelidae sensu stricto, and a clade of (Hyaenidae + (Herpestidae + Malagasy carnivorans)). All of the traditional "families," with the exception of Viverridae and Mustelidae, were robustly supported as monophyletic groups. We further have determined the relative positions of the major lineages within the Caniformia, which previous studies could not resolve, including the first robust support for the phylogenetic position of marine carnivorans (Pinnipedia) within the Arctoidea (as the sister-group to musteloids [sensu lato], with ursids as their sister group). Within the pinnipeds, Odobenidae (walrus) was more closely allied with otariids (sea lions/fur seals) than with phocids ("true" seals). In addition, we recovered a monophyletic clade of skunks and stink badgers (Mephitidae) and resolved the topology of musteloid interrelationships as: Ailurus (Mephitidae (Procyonidae, Mustelidae [sensu stricto])). This pattern of interrelationships of living caniforms suggests a novel inference that large body size may have been the primitive condition for Arctoidea, with secondary size reduction evolving later in some musteloids. Within Mustelidae, Bayesian analyses are unambiguous in supporting otter monophyly (Lutrinae), and in both MP and Bayesian analyses Martes is paraphyletic with respect to Gulo and Eira, as has been observed in some previous molecular studies. Within Feliformia, we have confirmed that Nandinia is the outgroup to all other extant feliforms, and that the Malagasy Carnivora are a monophyletic clade closely allied with the mongooses (Herpestidae [sensu stricto]). Although the monophyly of each of the three major feliform clades (Viverridae sensu stricto, Felidae, and the clade of Hyaenidae + (Herpestidae + Malagasy carnivorans)) is robust in all of our analyses, the relative phylogenetic positions of these three lineages is not resolvable at present. Our analyses document the monophyly of the "social mongooses," strengthening evidence for a single origin of eusociality within the Herpestidae. For a single caniform node, the position of pinnipeds relative to Ursidae and Musteloidea, parsimony analyses of data for the entire Carnivora did not replicate the robust support observed for both parsimony and Bayesian analyses of the caniform ingroup alone. More detailed analyses and these results demonstrate that outgroup choice can have a considerable effect on the strength of support for a particular topology. Therefore, the use of exemplar taxa as proxies for entire clades with diverse evolutionary histories should be approached with caution. The Bayesian analysis likelihood functions generally were better able to reconstruct phylogenetic relationships (increased resolution and more robust support for various nodes) than parsimony analyses when incompletely sampled taxa were included. Bayesian analyses were not immune, however, to the effects of missing data; lower resolution and support in those analyses likely arise from non-overlap of gene sequence data among less well-sampled taxa. These issues are a concern for similar studies, in which different gene sequences are concatenated in an effort to increase resolving power.
Anne Seltmann - One of the best experts on this subject based on the ideXlab platform.
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Species-specific differences in Toxoplasma gondii, Neospora caninum and Besnoitia besnoiti seroprevalence in Namibian wildlife
Parasites & Vectors, 2020Co-Authors: Anne Seltmann, Sonja K. Heinrich, Bettina Wachter, Susanne Thalwitzer, Gereon Schares, Ortwin H. K. Aschenborn, Gábor Á. CzirjákAbstract:Background Knowledge about parasitic infections is crucial information for animal health, particularly of free-ranging species that might come into contact with livestock and humans. Methods We investigated the seroprevalence of three tissue-cyst-forming apicomplexan parasites ( Toxoplasma gondii , Neospora caninum and Besnoitia besnoiti ) in 506 individuals of 12 wildlife species in Namibia using in-house enzyme linked immunosorbent assays (indirect ELISAs applying purified antigens) for screening and immunoblots as confirmatory tests. We included six species of the suborder Feliformia, four species of the suborder Caniformia and two species of the suborder Ruminantia. For the two species for which we had most samples and life-history information, i.e. cheetahs ( Acinonyx jubatus , n = 250) and leopards ( Panthera pardus , n = 58), we investigated T. gondii seroprevalence in relation to age class, sex, sociality (solitary, mother-offspring group, independent sibling group, coalition group) and site (natural habitat vs farmland). Results All but one carnivore species (bat-eared fox Otocyon megalotis , n = 4) were seropositive to T. gondii , with a seroprevalence ranging from 52.4% (131/250) in cheetahs to 93.2% (55/59) in African lions ( Panthera leo ). We also detected antibodies to T. gondii in 10.0% (2/20) of blue wildebeest ( Connochaetes taurinus ). Adult cheetahs and leopards were more likely to be seropositive to T. gondii than subadult conspecifics, whereas seroprevalence did not vary with sex, sociality and site. Furthermore, we measured antibodies to N. caninum in 15.4% (2/13) of brown hyenas ( Hyaena brunnea ) and 2.6% (1/39) of black-backed jackals ( Canis mesomelas ). Antibodies to B. besnoiti were detected in 3.4% (2/59) of African lions and 20.0% (4/20) of blue wildebeest. Conclusions Our results demonstrate that Namibian wildlife species were exposed to apicomplexan parasites at different prevalences, depending on parasite and host species. In addition to serological work, molecular work is also needed to better understand the sylvatic cycle and the clear role of wildlife in the epidemiology of these parasites in southern Africa.
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species specific differences in toxoplasma gondii neospora caninum and besnoitia besnoiti seroprevalence in namibian wildlife
Parasites & Vectors, 2020Co-Authors: Anne Seltmann, Sonja K. Heinrich, Bettina Wachter, Ortwin Aschenborn, Susanne Thalwitzer, Gereon Schares, Gábor Á. CzirjákAbstract:Knowledge about parasitic infections is crucial information for animal health, particularly of free-ranging species that might come into contact with livestock and humans. We investigated the seroprevalence of three tissue-cyst-forming apicomplexan parasites (Toxoplasma gondii, Neospora caninum and Besnoitia besnoiti) in 506 individuals of 12 wildlife species in Namibia using in-house enzyme linked immunosorbent assays (indirect ELISAs applying purified antigens) for screening and immunoblots as confirmatory tests. We included six species of the suborder Feliformia, four species of the suborder Caniformia and two species of the suborder Ruminantia. For the two species for which we had most samples and life-history information, i.e. cheetahs (Acinonyx jubatus, n = 250) and leopards (Panthera pardus, n = 58), we investigated T. gondii seroprevalence in relation to age class, sex, sociality (solitary, mother-offspring group, independent sibling group, coalition group) and site (natural habitat vs farmland). All but one carnivore species (bat-eared fox Otocyon megalotis, n = 4) were seropositive to T. gondii, with a seroprevalence ranging from 52.4% (131/250) in cheetahs to 93.2% (55/59) in African lions (Panthera leo). We also detected antibodies to T. gondii in 10.0% (2/20) of blue wildebeest (Connochaetes taurinus). Adult cheetahs and leopards were more likely to be seropositive to T. gondii than subadult conspecifics, whereas seroprevalence did not vary with sex, sociality and site. Furthermore, we measured antibodies to N. caninum in 15.4% (2/13) of brown hyenas (Hyaena brunnea) and 2.6% (1/39) of black-backed jackals (Canis mesomelas). Antibodies to B. besnoiti were detected in 3.4% (2/59) of African lions and 20.0% (4/20) of blue wildebeest. Our results demonstrate that Namibian wildlife species were exposed to apicomplexan parasites at different prevalences, depending on parasite and host species. In addition to serological work, molecular work is also needed to better understand the sylvatic cycle and the clear role of wildlife in the epidemiology of these parasites in southern Africa.
