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Eviatar Nevo - One of the best experts on this subject based on the ideXlab platform.
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Differential expression profiling of the blind subterranean mole rat Spalax ehrenbergi Superspecies: bioprospecting for hypoxia tolerance. Physiol Genomics 2006
2016Co-Authors: Aaron Avivi, Eviatar Nevo, Leonid Brodsky, Mark R. B, Mark RAbstract:ehrenbergi Superspecies: bioprospecting for hypoxia toleranc
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Brain organization and evolution in subterranean mole rats
Journal of Zoological Systematics and Evolutionary Research, 2009Co-Authors: Paul Pirlot, Eviatar NevoAbstract:Relative brain component sizes have been analyzed in subterranean mole rats of the Spalax ehren-bergi Superspecies in Israel. Our results indicate that brain size and brain component sizes may have evolved in association with specific stresses underground involving the distinct development of vocalzation, olfaction and tactile sensory communication systems all compensating for the loss of vision.
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Differential expression profiling of the blind subterranean mole rat Spalax ehrenbergi Superspecies: bioprospecting for hypoxia tolerance
Physiological Genomics, 2006Co-Authors: Aaron Avivi, Eviatar Nevo, Leonid Brodsky, Mark BandAbstract:The blind subterranean mole rat of the Spalax ehrenbergi Superspecies, living underground and exposed to fluctuating oxygen and carbon dioxide levels, is an excellent model of hypoxic tolerance. Un...
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Arthropods in the mounds of mole rats, Spalax ehrenbergi Superspecies, in Israel
Ecologia mediterranea, 2005Co-Authors: Tomáš Pavlíček, Vladimir Chikatunov, Eviatar NevoAbstract:A complex of invertebrates (mites, Collembola, earthworms, snails, Diplopoda, Myriapoda, Chilopoda, Isopoda and insects) was uncovered in large breeding mounds made by the blind subterranean mole rat (belonging to the species Spalax carmeli Nevo & Ivanitskaya & Beiles, 2000 of the Spalax ehrenbergi (Nehring, 1898) Superspecies) in the Haifa region, situated in the Northern Coastal Plain of Israel. The described properties of this complex were based on the 56 beetle species found there, mostly collected from the outer compact wall of the breeding mounds by forceps and exhausters. Most of the recorded beetle species were xerophiles or mesophiles and carnivores or detritivores. Only few species were phytophages, coprophages or necrophages. Since the invertebrate complex derives from the unique breeding mounds architecture, the mole rats can be considered as ecological architects of this microscale ecosystem.
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Molecular evolution of cytochrome b of subterranean mole rats, Spalax ehrenbergi Superspecies, in Israel.
Journal of Molecular Evolution, 1999Co-Authors: Eviatar Nevo, Avigdor Beiles, Theresa A. SpradlingAbstract:We describe the molecular evolution of cytochrome b of blind subterranean mole rats. We examined 12 individuals for nucleotide differences in the region of 402 base pairs of mitochondrial cytochrome b. Each individual represents a different population from the entire ecological and speciational range of the four chromosomal species in Israel (2n= 52, 54, 58, and 60) belonging to the Spalax ehrenbergi Superspecies. Our results indicate the following. (i) There are seven first-position transitional differences, compared to 34 variable third positions, with no observed second-position substitutions. (ii) A maximum of four amino acids differences occurs across the range. (iii) Within-species diversity increases southward. Only 1 autoapomorphic substitution characterizes either 2n= 52 or 2n= 54, but 6–11 substitutions characterize 2n= 58, and 9–13 substitutions characterize 2n= 60. (iv) Both parsimony and maximum-likelihood trees suggest two monophyletic groups: (a) 2n= 52 and 54, and (b) 2n= 58 and 60, as identified earlier by other protein and DNA markers. (v) Mitochondrial cytochrome b heterogeneity is significantly correlated with climatic factors (rainfall) and biotic factors (body size and allozymes). We hypothesize that two selective regimes direct cytochrome b evolution in the S. ehrenbergi Superspecies: (i) purifying selection in the flooded, mesic, hypoxic northern range of 2n= 52 and 54 and (ii) diversifying selection in the climatically spatiotemporal, xeric, and variable southern range of 2n= 58 and 60. Thus, the molecular evolution of mitochondrial cytochrome b in S. ehrenbergi is explicable by opposite selective stresses across the range of S. ehrenbergi in Israel, associated with the ecological adaptive radiation of the complex.
Avigdor Beiles - One of the best experts on this subject based on the ideXlab platform.
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Molecular evolution of cytochrome b of subterranean mole rats, Spalax ehrenbergi Superspecies, in Israel.
Journal of Molecular Evolution, 1999Co-Authors: Eviatar Nevo, Avigdor Beiles, Theresa A. SpradlingAbstract:We describe the molecular evolution of cytochrome b of blind subterranean mole rats. We examined 12 individuals for nucleotide differences in the region of 402 base pairs of mitochondrial cytochrome b. Each individual represents a different population from the entire ecological and speciational range of the four chromosomal species in Israel (2n= 52, 54, 58, and 60) belonging to the Spalax ehrenbergi Superspecies. Our results indicate the following. (i) There are seven first-position transitional differences, compared to 34 variable third positions, with no observed second-position substitutions. (ii) A maximum of four amino acids differences occurs across the range. (iii) Within-species diversity increases southward. Only 1 autoapomorphic substitution characterizes either 2n= 52 or 2n= 54, but 6–11 substitutions characterize 2n= 58, and 9–13 substitutions characterize 2n= 60. (iv) Both parsimony and maximum-likelihood trees suggest two monophyletic groups: (a) 2n= 52 and 54, and (b) 2n= 58 and 60, as identified earlier by other protein and DNA markers. (v) Mitochondrial cytochrome b heterogeneity is significantly correlated with climatic factors (rainfall) and biotic factors (body size and allozymes). We hypothesize that two selective regimes direct cytochrome b evolution in the S. ehrenbergi Superspecies: (i) purifying selection in the flooded, mesic, hypoxic northern range of 2n= 52 and 54 and (ii) diversifying selection in the climatically spatiotemporal, xeric, and variable southern range of 2n= 58 and 60. Thus, the molecular evolution of mitochondrial cytochrome b in S. ehrenbergi is explicable by opposite selective stresses across the range of S. ehrenbergi in Israel, associated with the ecological adaptive radiation of the complex.
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karyotype and genetic evolution in speciation of subterranean mole rats of the genus spalax in turkey
Biological Journal of The Linnean Society, 1995Co-Authors: Eviatar Nevo, Giora Heth, Maria Grazia Filippucci, Carlo Alberto Redi, Shimon Simson, Avigdor BeilesAbstract:Karyotype (2n) and allozyme diversity at 37 gene loci were determined in 69 subterranean mole rats in Turkey belonging to the two Superspecies: the ancestor Spalax leucodon (n = 55; 20 populations) and the descendant S. ehrenbergi (n = 14: four populations. We identified remarkable variation of diploid chromosome numbers in the S. leucodon Superspecies: 2n = 38, 40, 50, 54, 60 and 62; and in the S. ehrenbergi Superspecies: 2n = 52, 56 and 58. Genetic diversity indices were low on average in both S. leucodon and S. ehrenbergi Superspecies: Allele diversity, A = 1.081 and 1.074; polymorphism, P-50 0 = 0.077 and 0.068; heterozygosity, H = 0.038 and 0.027; and gene diversity, H = 0.038 and 0.034, respectively. H ranged from 0 in mesic or semimesic regions to 0.088 in arid Anatolia. We consider the populations with different diploid chromosome numbers, 2n, as good biological species. Karyotypic diversity may mark extensive ecological speciation. Nee's genetic distances, D average 0.174, range 0.002 0.422) and ecogeographical criteria suggest that almost each population may represent a different biological species, but critical future testing is necessary to support this claim. Karyotypes and allozymes are nonrandomly distributed across Turkey, displaying remarkable correlations with climatic and biotic factors. Both 2n and H are significantly correlated with aridity stress (2n/rainfall. r = −0.74; P < 0.001), and in our region also with climatic unpredictability. These results support the niche-width genetic variation hypothesis in space and time. Climatic selection in Turkey appears to be a major architect of karyotype and genetic (allozyme) diversity and divergence in mole rat evolution, in both speciation and adaptation.
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Homeobox DNA polymorphisms (RFLPs) in subterranean mammals of the Spalax ehrenbergi Superspecies in Israel: Patterns, correlates, and evolutionary significance
Journal of Experimental Zoology, 1992Co-Authors: Eviatar Nevo, Avigdor Beiles, Rachel Ben-shlomo, Charles P. Hart, Frank H. RuddleAbstract:Homeobox DNA polymorphisms (restriction fragment length polymorphisms, RFLPs) were first found in 13 individuals, and then in 121 subterranean mole rats of the Spalax ehrenbergi Superspecies in Israel. Spalacidae are adapted morphologically to life underground apparently since Oligocene times, 30 million years ago. The Superspecies S. ehrenbergi comprises four chromosomal species (2n = 52, 54, 58, and 60) displaying active speciation and dynamic adaptive radiation into four climatic regimes. A Hox-1.1 and -1.5 polymorphism was found with EcoRI, where three of four individuals of the species 2n = 60 were lacking the diagnostic locus-specific band present in all other nine individuals tested in the first stage. Next we found monomorphism in 121 animals in Hox-2.1 digested with five six-base recognition endonucleases (EcoRI, HindIII, BstEII, KpnI, BamHI, and one four-base enzyme, TaqI). However, we found in the same 121 animals from 13 populations of the four species in Hox-3.1 species-specific TaqI polymorphism in two populations of 2n = 54, and HindIII polymorphism in five populations, three of 2n = 54 and two of 2n = 58. The homeobox polymorphisms found display significant correlations with the burrow microclimates of mole rats. Furthermore, they are significantly correlated primarily with diverse morphological variables, and secondarily with protein (allozyme) and DNA polymorphisms, but very little with physiological and behavioral variables. We suggest that in subterranean mole rats, the variation in microclimatic factors, particularly in more unpredictable xeric regions, may maintain genetic polymorphisms by diversifying selection in the developmental control homeobox genes Hox-1.1, -1.5, and Hox-3.1, affecting regulatory morphogenetic processes in evolution. By contrast, the Hox-2.1 monomorphism suggests strong purifying selection for conservation across the Superspecies over long periods of evolutionary times. © 1992 Wiley-Liss, Inc.
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Selection for class II Mhc heterozygosity by parasites in subterranean mole rats.
Cellular and Molecular Life Sciences, 1992Co-Authors: Eviatar Nevo, Avigdor BeilesAbstract:Mhc organization and polymorphism have previously been studied26 in the four chromosomal species of theSpalax ehrenbergi Superspecies in Israel, serologically, and at the DNA, RFLP and sequence levels of class I and class II genes. Here we demonstrate that the observed heterozygosity ofMhc class II genesPα1 with 11 alleles, andQβ, with at least 14 alleles, is positively and significantly correlated with infectivities of ectoparasites (gamasid mites)17 and endoparasites (helminths)18.Mhc heterozygosity is highest in the most infected area, which is in the most humid-warm region of the Superspecies range, or where two zoogeographic regions overlap. We conclude that the evolutionary forces responsible for theMhc class II two-gene polymorphisms include selection for increased heterozygosity as a defense strategy against ecto- and endoparasite infections.
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Aldolase DNA polymorphism in subterranean mole-rats: genetic differentiation and environmental correlates
Heredity, 1990Co-Authors: Eviatar Nevo, Katsuji Hori, Avigdor BeilesAbstract:We analysed the genetic diversity and environmental correlates of the aldolase A and B genes by means of restriction endonucleases (DNA RFLP analysis), in the four chromosomal species (2n =52, 54, 58 and 60) of the actively speciating subterranean mole-rats of the Spalax ehrenbergi Superspecies in Israel. The results indicated that: (i) both aldolase genes are highly polymorphic; (ii) Fragment frequencies and fragment profiles display geographical patterns and significant ecological correlates; (iii) discriminant analysis largely succeeded in separating the four chromosomal species on the basis of variation of aldolase RFLPs.
Giora Heth - One of the best experts on this subject based on the ideXlab platform.
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Individual odour similarities across species parallel phylogenetic relationships in the S. ehrenbergi Superspecies of mole-rats.
Animal Behaviour, 2000Co-Authors: Giora Heth, Josephine TodrankAbstract:Research using habituation techniques has shown that rodents from the same kin group, population, or species share similarities in their individual odours that covary with shared genetic similarities between them, that is, the closer their genetic relatedness, the more similar their odours. We assessed similarities in individual odours across four sibling species of subterranean mole-rats from the Spalax ehrenbergi Superspecies in Israel. Mole-rats were habituated to the urine odour of a same-sex individual from one species then tested with urine odours of individuals from two different species of the Superspecies. Subjects treated urine odours of individuals from more closely genetically related species as similar compared with the odours of individuals from a less closely related species, showing that the covariance between odours and genes extends across species. These similarities in odour also paralleled genetic similarities determined by molecular analysis: odours of descendent species were perceived as similar to those of their closest ancestral species, suggesting that some qualities of the odour of the ancestral species persist in the descendent species. It is generally assumed that during speciation incipient species develop species-specific markers, including, for example, odour markers, to facilitate discrimination of conspecifics from close ancestral heterospecifics. Our findings indicate that similarities in odours across species are more salient than species-specific odour markers. Such findings may also have important implications for mechanisms of species recognition.
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Seasonal changes in urinary odors and in responses to them by blind subterranean mole rats
Physiology & Behavior, 1996Co-Authors: Giora Heth, Eviatar Nevo, Josephine TodrankAbstract:Breeding and nonbreeding season male and female mole rats from two chromosomal species of the Spalax ehrenbergi Superspecies were tested in a tunnel T-maze to assess their responses to urine collected from breeding- and nonbreeding season male and female conspecific and heterospecific donors. The results indicate that S. ehrenbergi mole rat urine contains species-, sex-, and season-specific chemosensory cues and that male and female mole rats change their responses to these chemosensory cues depending upon the season. During the nonbreeding season, mole rats avoid conspecific and heterospecific urine of both sexes. In contrast, during the breeding season, mole rats do not avoid conspecific urine and males do not avoid heterospecific urine. These changes in responses to the chemosensory cues in urine are adaptive to their seasonal life underground because they could help the animals avoid aggressive encounters during the nonbreeding season and facilitate their approaching potential mates and competitors during the breeding season. The results suggest that chemical communication could play a role in social encounters, reproduction, and species isolation in the S. ehrenbergi Superspecies.
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karyotype and genetic evolution in speciation of subterranean mole rats of the genus spalax in turkey
Biological Journal of The Linnean Society, 1995Co-Authors: Eviatar Nevo, Giora Heth, Maria Grazia Filippucci, Carlo Alberto Redi, Shimon Simson, Avigdor BeilesAbstract:Karyotype (2n) and allozyme diversity at 37 gene loci were determined in 69 subterranean mole rats in Turkey belonging to the two Superspecies: the ancestor Spalax leucodon (n = 55; 20 populations) and the descendant S. ehrenbergi (n = 14: four populations. We identified remarkable variation of diploid chromosome numbers in the S. leucodon Superspecies: 2n = 38, 40, 50, 54, 60 and 62; and in the S. ehrenbergi Superspecies: 2n = 52, 56 and 58. Genetic diversity indices were low on average in both S. leucodon and S. ehrenbergi Superspecies: Allele diversity, A = 1.081 and 1.074; polymorphism, P-50 0 = 0.077 and 0.068; heterozygosity, H = 0.038 and 0.027; and gene diversity, H = 0.038 and 0.034, respectively. H ranged from 0 in mesic or semimesic regions to 0.088 in arid Anatolia. We consider the populations with different diploid chromosome numbers, 2n, as good biological species. Karyotypic diversity may mark extensive ecological speciation. Nee's genetic distances, D average 0.174, range 0.002 0.422) and ecogeographical criteria suggest that almost each population may represent a different biological species, but critical future testing is necessary to support this claim. Karyotypes and allozymes are nonrandomly distributed across Turkey, displaying remarkable correlations with climatic and biotic factors. Both 2n and H are significantly correlated with aridity stress (2n/rainfall. r = −0.74; P < 0.001), and in our region also with climatic unpredictability. These results support the niche-width genetic variation hypothesis in space and time. Climatic selection in Turkey appears to be a major architect of karyotype and genetic (allozyme) diversity and divergence in mole rat evolution, in both speciation and adaptation.
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Seismic communication in the blind subterranean mole‐rat: patterns of head thumping and of their detection in the Spalax ehrenbergi Superspecies in Israel
Journal of Zoology, 1991Co-Authors: Giora Heth, Elizabeth Frankenberg, H. Pratt, Eviatar NevoAbstract:Patterns of seismic communication and somatosensory responses were studied in four chromosomal species (2n= 52, 54, 58, 60) of blind subterranean mole-rats, belonging to the Spalax ehrenbergi Superspecies in Israel. The patterns involved head thumping signals and surface-recorded cerebral potentials evoked by vibrational signals. The patterns correspond to the differences in territory size and population density which characterize the four species. It is suggested that this correspondence is related to the adaptive significance of the seismic communication.
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seismic communication in the blind subterranean mole rat patterns of head thumping and of their detection in the spalax ehrenbergi Superspecies in israel
Journal of Zoology, 1991Co-Authors: Giora Heth, Elizabeth Frankenberg, H. Pratt, Eviatar NevoAbstract:Patterns of seismic communication and somatosensory responses were studied in four chromosomal species (2n= 52, 54, 58, 60) of blind subterranean mole-rats, belonging to the Spalax ehrenbergi Superspecies in Israel. The patterns involved head thumping signals and surface-recorded cerebral potentials evoked by vibrational signals. The patterns correspond to the differences in territory size and population density which characterize the four species. It is suggested that this correspondence is related to the adaptive significance of the seismic communication.
Robert G. Moyle - One of the best experts on this subject based on the ideXlab platform.
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relationships of morphological groups in the northern flicker Superspecies complex colaptes auratus c chrysoides
Systematics and Biodiversity, 2017Co-Authors: Joseph D. Manthey, Mark Geiger, Robert G. MoyleAbstract:Many species complexes have diversified rapidly and recently, resulting in morphologically diverse populations; however, the rapid pace of diversification often prevents identification of clear phylogeographic structure. Recently, the use of large genomic and reduced-representation genomic datasets has improved resolution of the evolutionary histories in such species and allowed identification of lineages on distinct evolutionary trajectories. The northern flicker (Colaptes auratus) and gilded flicker (Colaptes chrysoides) form a polytypic Superspecies group with a complex taxonomic history. The Superspecies group includes up to 13 described subspecies, which represent slight geographic variation among five main morphological groups: red-shafted flickers of western North America (cafer group), yellow-shafted flickers of eastern North America (auratus group), Cuban flickers of the Caribbean (chrysocaulosus group), gilded flickers of the U.S. south-west and Mexican north-west (chrysoides group), and Guatema...
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Relationships of morphological groups in the northern flicker Superspecies complex (Colaptes auratus & C. chrysoides)
Systematics and Biodiversity, 2016Co-Authors: Joseph D. Manthey, Mark Geiger, Robert G. MoyleAbstract:Many species complexes have diversified rapidly and recently, resulting in morphologically diverse populations; however, the rapid pace of diversification often prevents identification of clear phylogeographic structure. Recently, the use of large genomic and reduced-representation genomic datasets has improved resolution of the evolutionary histories in such species and allowed identification of lineages on distinct evolutionary trajectories. The northern flicker (Colaptes auratus) and gilded flicker (Colaptes chrysoides) form a polytypic Superspecies group with a complex taxonomic history. The Superspecies group includes up to 13 described subspecies, which represent slight geographic variation among five main morphological groups: red-shafted flickers of western North America (cafer group), yellow-shafted flickers of eastern North America (auratus group), Cuban flickers of the Caribbean (chrysocaulosus group), gilded flickers of the U.S. south-west and Mexican north-west (chrysoides group), and Guatema...
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Relationships of morphological groups in the northern flicker Superspecies complex (Colaptes auratus & C. chrysoides)
2016Co-Authors: Joseph D. Manthey, Mark Geiger, Robert G. MoyleAbstract:Many species complexes have diversified rapidly and recently, resulting in morphologically diverse populations; however, the rapid pace of diversification often prevents identification of clear phylogeographic structure. Recently, the use of large genomic and reduced-representation genomic datasets has improved resolution of the evolutionary histories in such species and allowed identification of lineages on distinct evolutionary trajectories. The northern flicker (Colaptes auratus) and gilded flicker (Colaptes chrysoides) form a polytypic Superspecies group with a complex taxonomic history. The Superspecies group includes up to 13 described subspecies, which represent slight geographic variation among five main morphological groups: red-shafted flickers of western North America (cafer group), yellow-shafted flickers of eastern North America (auratus group), Cuban flickers of the Caribbean (chrysocaulosus group), gilded flickers of the U.S. south-west and Mexican north-west (chrysoides group), and Guatemalan flickers of Central America (mexicanoides group). These groups are largely differentiable by variation in feather shaft colour, malar colour, throat colour, crown colour, and back barring. Here, using mitochondrial DNA (mtDNA) and hundreds of single nucleotide polymorphisms (SNPs), we characterized the genetic relationships and genomic distinctiveness of the five morphological groups. We found the mexicanoides group to be the most genetically distinct in both mtDNA (∼1.4% sequence divergence) and large SNP panels. The chrysocaulosus group is differentiated by a single basepair mutation in a small mtDNA fragment. In both mtDNA and SNP panels, there is little genetic distinctiveness between auratus, cafer, and chrysoides morphological groups, with evidence of admixture and a lack of fixed differences.
Alexandre Aleixo - One of the best experts on this subject based on the ideXlab platform.
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HISTORICAL DIVERSIFICATION OF A TERRA‐FIRME FOREST BIRD Superspecies: A PHYLOGEOGRAPHIC PERSPECTIVE ON THE ROLE OF DIFFERENT HYPOTHESES OF AMAZONIAN DIVERSIFICATION
Evolution, 2004Co-Authors: Alexandre AleixoAbstract:Abstract Among those few hypotheses of Amazonian diversification amenable to falsification by phylogenetic and population genetics methods, three can be singled out because of their general application to vertebrates: the riverine barrier, the refuge, and the Miocene marine incursion hypotheses. I used phylogenetic and population genetics methods to reconstruct the diversification history of the upland (terra-firme) forest Superspecies Xiphorhynchus spixii/elegans (Aves: Dendrocolaptidae) in Amazonia, and to evaluate predictions of the riverine barrier, refuge, and Miocene marine incursion hypotheses. Phylogeographic and population genetics analyses of the X. spixii/elegans Superspecies indicated that the main prediction of the riverine barrier hypothesis (that sister lineages occur across major rivers) hold only for populations separated by “clear-water” rivers located on the Brazilian shield, in central and eastern Amazonia; in contrast, “white-water” rivers located in western Amazonia did not represent...
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historical diversification of a terra firme forest bird Superspecies a phylogeographic perspective on the role of different hypotheses of amazonian diversification
Evolution, 2004Co-Authors: Alexandre AleixoAbstract:Abstract Among those few hypotheses of Amazonian diversification amenable to falsification by phylogenetic and population genetics methods, three can be singled out because of their general application to vertebrates: the riverine barrier, the refuge, and the Miocene marine incursion hypotheses. I used phylogenetic and population genetics methods to reconstruct the diversification history of the upland (terra-firme) forest Superspecies Xiphorhynchus spixii/elegans (Aves: Dendrocolaptidae) in Amazonia, and to evaluate predictions of the riverine barrier, refuge, and Miocene marine incursion hypotheses. Phylogeographic and population genetics analyses of the X. spixii/elegans Superspecies indicated that the main prediction of the riverine barrier hypothesis (that sister lineages occur across major rivers) hold only for populations separated by “clear-water” rivers located on the Brazilian shield, in central and eastern Amazonia; in contrast, “white-water” rivers located in western Amazonia did not represent...