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  • 1.
    Andersson Escher, Stefan
    et al.
    Umeå universitet, Teknisk-naturvetenskapliga fakulteten, Institutionen för molekylärbiologi (Teknisk-naturvetenskaplig fakultet).
    Ekenstedt, J
    Elberg, K
    Saura, Anssi
    Umeå universitet, Teknisk-naturvetenskapliga fakulteten, Institutionen för molekylärbiologi (Teknisk-naturvetenskaplig fakultet).
    The Drosophilidae (Diptera) of Estonia2006Inngår i: Entomologica Fennica, Vol. 17, s. 13-20Artikkel i tidsskrift (Fagfellevurdert)
  • 2. Brown Jr, Keith S
    et al.
    Freitas, André V L
    von Schoultz, Barbara
    Saura, Anja O
    Saura, Anssi
    Umeå universitet, Teknisk-naturvetenskaplig fakultet, Molekylärbiologi (Teknisk-naturvetenskaplig fakultet).
    Chromosomal evolution of South American frugivorous butterflies in the Satyroid clade (Nymphalidae: Charaxinae, Morphinae and Satyrinae)2007Inngår i: Biological Journal of the Linnean Society, Vol. 92, s. 467-481Artikkel i tidsskrift (Fagfellevurdert)
  • 3. Brown, Keith S
    et al.
    Freitas, André Victor Lucci
    Wahlberg, Niklas
    Von Schoultz, Barbara
    Saura, Anja O
    Saura, Anssi
    Umeå universitet, Teknisk-naturvetenskaplig fakultet, Molekylärbiologi (Teknisk-naturvetenskaplig fakultet).
    Chromosomal evolution in the South American Nymphalidae.2007Inngår i: Hereditas, ISSN 1601-5223, Vol. 144, nr 4, s. 137-48Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    We give the chromosome numbers of about 80 species or subspecies of Biblidinae as well as of numbers of neotropical Libytheinae (one species), Cyrestinae (4) Apaturinae (7), Nymphalinae (about 40), Limenitidinae (16) and Heliconiinae (11). Libytheana has about n=32, the Biblidinae, Apaturinae and Nymphalinae have in general n=31, the Limenitidinae have n=30, the few Argynnini n=31 and the few species of Acraeni studied have also mostly n=31. The results agree with earlier data from the Afrotropical species of these taxa. We supplement these data with our earlier observations on Heliconiini, Danainae and the Neotropical Satyroid taxa. The lepidopteran modal n=29-31 represents clearly the ancestral condition among the Nymphalidae, from which taxa with various chromosome numbers have differentiated. The overall results show that Neotropical taxa have a tendency to evolve karyotype instability, which is in stark contrast to the otherwise stable chromosome numbers that characterize both Lepidoptera and Trichoptera.

  • 4. Brown, Keith S., Jr.
    et al.
    von Schoultz, Barbara
    Saura, Anja O.
    Saura, Anssi
    Umeå universitet, Teknisk-naturvetenskapliga fakulteten, Institutionen för molekylärbiologi (Teknisk-naturvetenskaplig fakultet).
    Chromosomal evolution in the South American Riodinidae (Lepidoptera Papilionoidea)2012Inngår i: Hereditas, ISSN 0018-0661, E-ISSN 1601-5223, Vol. 149, nr 4, s. 128-138Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    We give the haploid chromosome numbers of 173 species or subspecies of Riodinidae as well as of 17 species or subspecies of neotropical Lycaenidae for comparison. The chromosome numbers of riodinids have thus far been very poorly known. We find that their range of variation extends from n =?9 to n =?110 but numbers above n =?31 are rare. While lepidopterans in general have stable chromosome numbers, or variation is limited at most a subfamily or genus, the entire family Riodinidae shows variation within genera, tribes and subfamilies with no single modal number. In particular, a stepwise pattern with chromosome numbers that are about even multiples is seen in several unrelated genera. We propose that this variation is attributable to the small population sizes, fragmented populations with little migration, and the behavior of these butterflies. Small and isolated riodinid populations would allow for inbreeding to take place. Newly arisen chromosomal variants could become fixed and contribute to reproductive isolation and speciation. In contrast to the riodinids, the neotropical Lycaenidae (Theclinae and Polyommatinae) conform to the modal n =?24 that characterizes the family.

  • 5. Drotz, Marcus K.
    et al.
    Brodin, Tomas
    Umeå universitet, Teknisk-naturvetenskapliga fakulteten, Institutionen för ekologi, miljö och geovetenskap.
    Saura, Anssi
    Umeå universitet, Teknisk-naturvetenskapliga fakulteten, Institutionen för molekylärbiologi (Teknisk-naturvetenskaplig fakultet).
    Giles, Barbara E.
    Umeå universitet, Teknisk-naturvetenskapliga fakulteten, Institutionen för ekologi, miljö och geovetenskap.
    Ecotype Differentiation in the Face of Gene Flow within the Diving Beetle Agabus bipustulatus (Linnaeus, 1767) in Northern Scandinavia2012Inngår i: PLoS ONE, ISSN 1932-6203, E-ISSN 1932-6203, Vol. 7, nr 2, s. e31381-Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    The repeated occurrence of habitat-specific polyphyletic evolved ecotypes throughout the ranges of widely distributed species implies that multiple, independent and parallel selection events have taken place. Ecological transitions across altitudinal gradients over short geographical distances are often associated with variation in habitat-related fitness, these patterns suggest the action of strong selective forces. Genetic markers will therefore contribute differently to differences between ecotypes in local hybrid zones. Here we have studied the adaptive divergence between ecotypes of the water beetle Agabus bipustulatus along several parallel altitudinal gradients in northern Scandinavia. This water beetle is well known for its remarkable morphological variation associated with mountain regions throughout the western Palaearctic. Two morphological ecotypes are recognised: a montane type with reduced flight muscles and a lowland type with fully developed muscles. Using a multilocus survey of allozyme variation and a morphological analysis with landmark-based morphometrics, across thirty-three populations and seven altitudinal gradients, we studied the local adaptive process of gene flow and selection in detail. Populations were sampled at three different elevations: below, at and above the tree line. The results indicate that the levels of divergence observed between ecotypes in morphology and allele frequencies at alpha-Glycerophosphate dehydrogenase relative to those shown by neutral molecular markers reflects local diversifying selection in situ. Four main lines of evidence are shown here: (1) A repeated morphological pattern of differentiation is observed across all altitudinal transects, with high reclassification probabilities. (2) Allele and genotype frequencies at the alpha-Gpdh locus are strongly correlated with altitude, in sharp contrast to the presumable neutral markers. (3) Genetic differentiation is two to three times higher among populations across the tree line than among populations at or below. (4) Genetic differentiation between ecotypes within independent mountain areas is reflected by different sets of allozymes.

  • 6. Drotz, Marcus K.
    et al.
    Savolainen, Eino
    Saura, Anssi
    Umeå universitet, Teknisk-naturvetenskapliga fakulteten, Institutionen för molekylärbiologi (Teknisk-naturvetenskaplig fakultet).
    Stahls, Gunilla
    The genetic population structure of lotic and lentic mayflies of the Baetis vernus group (Ephemeroptera: Baetidae)2012Inngår i: Canadian Entomologist, ISSN 0008-347X, E-ISSN 1918-3240, Vol. 144, nr 5, s. 679-690Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    Nymphs of lotic mayflies live in environments that are expected to give rise to different degrees of population structuring. Here we investigate two taxa adapted to different lifestyles. Baetis macani Kimmins (Ephemeroptera: Baetidae) lives in flowing water; brooks that may periodically dry out in the summer or freeze to the bottom in winter. Baetis jaervii Savolainen is mostly found in sedge belts along the shores of lakes. Most insects living in flowing water show low levels of among-population genetic differentiation within and among catchments. Levels of differentiation in the lotic species are therefore assumed to be lower than in lentic B. jaervii. Here we test this hypothesis. Mitochondrial DNA and allele frequencies of nuclear genes were used to detect population structure in specimens originating from an extensive area from northern Finland. The genetic differentiation among populations of the lotic B. macani is more than twice the corresponding value for the lentic B. jaervii (F-ST 0.33 versus 0.15, while the mean F-ST between species was 0.33 and significant). The result is congruent within the cytochrome c oxidase subunit I gene (COI) partial gene frequencies. We argue that the significant genetic population structure, which only was found in the lotic B. macani, is differentiated as a consequence to the unpredictable environment as contrasted to the stable environment in standing bodies of water.

  • 7.
    Lundmark, Magnus
    et al.
    Umeå universitet, Teknisk-naturvetenskapliga fakulteten, Institutionen för molekylärbiologi (Teknisk-naturvetenskaplig fakultet).
    Saura, Anssi
    Umeå universitet, Teknisk-naturvetenskapliga fakulteten, Institutionen för molekylärbiologi (Teknisk-naturvetenskaplig fakultet).
    Asexuality alone does not explain the success of clonal forms in insects with geographical parthenogenesis2006Inngår i: Hereditas, ISSN 0018-0661, E-ISSN 1601-5223, Vol. 143, nr 2006, s. 23-32Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    Asexual forms of invertebrates are relatively common. They are often more successful than their sexual progenitors. Especially in insects, the pattern called geographical parthenogenesis shows that asexuality is important in speciation and ecological adaptation. In geographical parthenogenesis the clones have a wider distribution than the sexual forms they originate from. This indicates that they have a broader niche they may utilize successfully. The cause of this apparent success is, however, hard to come by as the term asexuality covers separate phenomena that are hard to disentangle from the mode of reproduction itself. Asexual insects are often polyploid, of hybrid origin, or both and these phenomena have been argued to explain the distribution patterns better than clonality. In this study we survey the literature on arthropods with geographical parthenogenesis in an attempt to clarify what evidence there is for the different phenomena explaining the success of the clonal forms. We focus on the few species where knowledge of distribution of different ploidy levels allows for a distinction of contributions from different phenomena to be made. Our survey support that asexuality is not the only factor underlying the success of all asexuals. Evidence about the importance of a hybrid origin of the clones is found to be meagre as the origin of clones is unknown in the majority of cases. Asexuality, hybridity and polyploidy are intertwined phenomena that each and all may contribute to the success of clonal taxa. Polyploidy, however, emerges as the most parsimonious factor explaining the success of these asexual invertebrate taxa.

  • 8. Nyberg Berglund, Anna-Britt
    et al.
    Saura, Anssi
    Umeå universitet, Teknisk-naturvetenskaplig fakultet, Molekylärbiologi (Teknisk-naturvetenskaplig fakultet).
    Westerbergh, Anna
    Electrophoretic evidence for disomic inheritance and allopolyploid origin of the octoploid Cerastium alpinum (Caryophyllaceae).2006Inngår i: J Hered, ISSN 0022-1503, Vol. 97, nr 3, s. 296-302Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    The mode of inheritance of six enzyme markers in the octoploid alpine plant Cerastium alpinum was analyzed. Offspring from crosses between heterozygotes showed fixed heterozygosity at malate dehydrogenase-2, phosphoglucoisomerase-2, triosephosphate isomerase-2, and triosephosphate isomerase-3. Phosphoglucomutase-1 also showed fixed heterozygosity except in offspring from one cross. Fixed heterozygosity in five enzyme systems suggests that C. alpinum has originated through at least some allopolyploidization. Offspring from plants heterozygous for two alleles at the menadione reductase-1 (Mr-1) locus did not deviate significantly from a 1:2:1 ratio. The large proportion of homozygotes suggests disomic inheritance because any kind of polysomic inheritance would result in a substantially increased proportion of heterozygotes relative to disomic inheritance. Assuming a diploid model for Mr-1, this locus was used to analyze the population genetic structure within C. alpinum populations. Inbreeding was found in many alpine populations. This may help explain the large genetic distances found among alpine populations in a previous study. The analysis is only based on one segregating locus, and the results should therefore be treated with caution. However, by establishing the mode of inheritance through crosses, we have been able to use a codominant marker in population genetic analysis of an octoploid plant.

  • 9.
    Pecsenye, K
    et al.
    Department of Evolutionary Zoology, University of Debrecen, Debrecen, Hungary.
    Komlósi, I
    Department of Animal Breeding, Agricultural Centre, University of Debrecen, Debrecen, Hungary.
    Saura, A
    Umeå universitet, Medicinska fakulteten, Institutionen för medicinsk biovetenskap, Medicinsk och klinisk genetik.
    Heritabilities and additive genetic variances of the activities of some enzymes in Drosophila melanogaster populations living in different habitats2004Inngår i: Heredity, ISSN 0018-067X, E-ISSN 1365-2540, Vol. 93, s. 215-221Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    Drosophila melanogaster samples were collected from a large population in two habitats: farmyards and distilleries. Samples were taken from two villages in each habitat. Three isofemale lines were established from all four samples and full-sib crosses were set in each isofemale line. Activities of four enzymes (ADH, GPDH, IDH and 6PGDH) were measured in the offspring of each cross on starch gel after electrophoresis. Broad sense heritabilities and additive genetic variances were estimated in all four samples.Most of the activity variation was observed within the isofemale lines. The isofemale lines tended to be more different in the distilleries than in the farmyards. There was no significant difference in the average activities between the two habitats for any of the enzymes investigated. The additive genetic variance of the enzyme activities did not exhibit a consistent habitat pattern. In the farmyard habitat, we detected a higher activity variation in Tiszafüred than in the other village. Strong correlation was observed among the activities of the enzymes investigated. Correlation coefficients indicated higher level of correlation in the samples collected in Tiszafüred than in those originating from Tiszaszls. The heritability values were rather high and they had a considerable variation both between the habitats and across the enzymes.

  • 10. Pecsenye, Katalin
    et al.
    Saura, Anssi
    Umeå universitet, Teknisk-naturvetenskaplig fakultet, Molekylärbiologi (Teknisk-naturvetenskaplig fakultet).
    Enzyme activities and alcohol tolerance in isofemale lines of Drosophila melanogaster originating from different habitats.2004Inngår i: Genetica, ISSN 0016-6707, Vol. 121, nr 3, s. 277-83Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    Enzyme activity variation was studied in a Drosophila melanogaster population from two villages (Tiszafüred and Tiszaszolos) in Hungary. Two habitats (distillery and farmyard) were sampled in both villages and 8-9 isofemale lines were established from each sample with a total of 35 lines. The activities of ADH, alphaGPDH, IDH and 6PGDH were determined on starch gel after electrophoresis in 10 F1 females of each of the 35 isofemale lines. Three sublines were established from three selected isofemale lines of all four samples (altogether 36 sublines). Alcohol tolerance of the adult flies was assayed in these sublines. The activity of ADH was similar in the two habitats; so was the sensitivity to ethanol. Accordingly, no differences in adaptation to environmental ethanol were detected between the two habitats. The deviations between the two habitats in average activities and in the total variation of enzyme activities were not consistent in the two villages. These results suggest that founder effects and genetic drift are more pronounced in distilleries than selection. The association among enzyme activities varied greatly both between the two villages and between the two habitats. The two parameters of alcohol tolerance were not significantly different between the two habitats in any of the two villages.

  • 11.
    Saura, Anssi
    Umeå universitet, Medicinska fakulteten, Institutionen för molekylärbiologi (Medicinska fakulteten).
    A tale of two papers2014Inngår i: Hereditas, ISSN 0018-0661, E-ISSN 1601-5223, Vol. 151, nr 6, s. 119-122Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    Two papers published in HEREDITAS between 1921 and 1939 show how the attitude towards race biology changed in the course of the interwar period in the Nordic countries. In the early 1920s race biology was seen to constitute a legitimate science. Ordinary human genetics prevailed, however, over race biology already in the very beginning on the pages of HEREDITAS. Population thinking was introduced into the study of human heredity around the year 1930. It effectively contradicted the concept of the race. Interestingly, HEREDITAS does not carry a single paper on eugenics and sterilization. In 1939 we see a final repudiation of the doctrines on race. Times had changed and the National Socialists had usurped the doctrines of race in Germany.

  • 12.
    Saura, Anssi
    Umeå universitet, Teknisk-naturvetenskaplig fakultet, Molekylärbiologi (Teknisk-naturvetenskaplig fakultet).
    Karl Gustav Lüning: Minnesanteckningar över avlidna ledamöter2004Inngår i: Fysiografiska Sällskapets Årsbok: Minnesanteckningar över avlidna ledamöter, 2004, s. 131-132Kapittel i bok, del av antologi (Annet (populærvitenskap, debatt, mm))
  • 13.
    Saura, Anssi
    et al.
    Umeå universitet, Teknisk-naturvetenskapliga fakulteten, Institutionen för molekylärbiologi (Teknisk-naturvetenskaplig fakultet).
    Von Schoultz, Barbara
    Saura, Anja O.
    Brown, Keith S., Jr.
    Chromosome evolution in Neotropical butterflies2013Inngår i: Hereditas, ISSN 0018-0661, E-ISSN 1601-5223, Vol. 150, nr 2-3, s. 26-37Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    We list the chromosome numbers for 65 species of Neotropical Hesperiidae and 104 species or subspecies of Pieridae. In Hesperiidae the tribe Pyrrhopygini have a modal n = 28, Eudaminae and Pyrgini a modal n = 31, while Hesperiinae have n = around 29. Among Pieridae, Coliadinae have a strong modal n = 31 and among Pierinae Anthocharidini are almost fixed for n = 15 while Pierini vary with n = 26 as the most common chromosome number. Dismorphiinae show wide variation. We discuss these results in the context of chromosome numbers of over 1400 Neotropical butterfly species and subspecies derived from about 3000 populations published here and in earlier papers of a series. The overall results show that many Neotropical groups are characterized by karyotype instability with several derived modal numbers or none at all, while almost all taxa of Lepidoptera studied from the other parts of the world have one of n = 29-31 as modal numbers. Possibly chromosome number changes become fixed in the course of speciation driven by biotic interactions. Population subdivision and structuring facilitate karyotype change. Factors that stabilize chromosome numbers include hybridization among species sharing the same number, migration, sexual selection and possibly the distribution of chromosomes within the nucleus.

  • 14. Savolainen, Eino
    et al.
    Drotz, Marcus K
    Per-Ola, Hoffsten
    Saura, Anssi
    Umeå universitet, Teknisk-naturvetenskaplig fakultet, Molekylärbiologi (Teknisk-naturvetenskaplig fakultet).
    The Baetis vernus group (Ephemeroptera: Baetidae) of northernmost Europe: an evidently diverse but poorly understood group of mayflies2007Inngår i: Entomologica Fennica, Vol. 6, s. 160-167Artikkel i tidsskrift (Fagfellevurdert)
  • 15. Savolainen, Eino
    et al.
    Drotz, Marcus K.
    Saura, Anssi
    Umeå universitet, Medicinska fakulteten, Institutionen för molekylärbiologi (Medicinska fakulteten).
    Stahls, Gunilla
    Baetis bundyae (Ephemeroptera: Baetidae), described from Arctic Canada is found in northernmost Europe2014Inngår i: Canadian Entomologist, ISSN 0008-347X, E-ISSN 1918-3240, Vol. 146, nr 6, s. 621-629Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    The taxonomy and identification of mayflies of the Baetis vernus group (Ephemeroptera: Baetidae) represents a major challenge in both Europe and North America. The recent description of B. jaervii Savolainen from Finland, a species taxonomically close to the Palaearctic taxon Baetis macani Kimmins and the Nearctic B. bundyae Lehmkuhl, called for clarification of the status and distribution of these species in northernmost Europe. We generated mtDNA COI sequences for establishing the identity of the collected samples. Based on these data we conclude that B. bundyae does occur in northeastern Finland in sympatry with B. macani. Accordingly, this taxon shows a highly interesting distributional pattern across the Nearctic and western Palaearctic regions.

  • 16. Stenberg, Per
    et al.
    Lundmark, Magnus
    Umeå universitet, Teknisk-naturvetenskapliga fakulteten, Institutionen för molekylärbiologi (Teknisk-naturvetenskaplig fakultet).
    Knutelski, Stanislaw
    Saura, Anssi
    Evolution of clonality and polyploidy in a weevil system2003Inngår i: Molecular biology and evolution, ISSN 0737-4038, Vol. 20, nr 10, s. 1626-1632Artikkel i tidsskrift (Fagfellevurdert)
  • 17. Stenberg, Per
    et al.
    Lundmark, Magnus
    Umeå universitet, Teknisk-naturvetenskapliga fakulteten, Institutionen för molekylärbiologi (Teknisk-naturvetenskaplig fakultet).
    Saura, Anssi
    MLGsim: a program for detecting clones using a simulation approach2003Inngår i: Molecular ecology notes, ISSN 1471-8278, Vol. 3, nr 2, s. 329-331Artikkel i tidsskrift (Fagfellevurdert)
  • 18.
    Stenberg, Per
    et al.
    Umeå universitet, Medicinska fakulteten, Institutionen för molekylärbiologi (Medicinska fakulteten). Umeå universitet, Medicinska fakulteten, Umeå centrum för molekylär patogenes (UCMP) (Medicinska fakulteten).
    Saura, Anssi
    Umeå universitet, Medicinska fakulteten, Institutionen för molekylärbiologi (Medicinska fakulteten).
    Cytology of Asexual Animals2009Inngår i: Lost Sex: The Evolutionary Biology of Parthenogenesis / [ed] Isa Schön, Koen Martens, Peter Dijk, Dordrecht: Springer Netherlands, 2009, s. 63-74Kapittel i bok, del av antologi (Annet vitenskapelig)
    Abstract [en]

    We review the cytological mechanisms underlying asexual reproduction, i.e. reproduction without fertilization, in animals. Asexuality or parthenogenesis has evolved many times and the cytological mechanisms to restore the parental chromosome number can vary between and even within species. In automictic or meiotic parthenogenesis, meiosis takes place but the chromosomal constitution of the mother is restored through one or several different mechanisms. Some of these mechanisms enforce homozygosity at all loci while some other mechanisms pass the genome of the mother intact to the offspring. In apomictic or mitotic parthenogenesis the eggs are formed through what is essentially a set of mitoses. Polyploidy, is in general incompatible with chromosomal sex determination and is a rare condition in animals. However, many asexual and hermaphroditic forms are polyploid to various degrees. Polyploidy is divided into allo- and autopolyploidy. In the former mode the chromosome sets are derived from two or more different species while in autopolyploidy the multiplication has taken place within one species. We discuss the evolutionary consequences of the different cytological mechanisms involved in asexual reproduction.

  • 19.
    Stenberg, Per
    et al.
    Umeå universitet, Teknisk-naturvetenskapliga fakulteten, Institutionen för molekylärbiologi (Teknisk-naturvetenskaplig fakultet).
    Saura, Anssi
    Umeå universitet, Teknisk-naturvetenskapliga fakulteten, Institutionen för molekylärbiologi (Teknisk-naturvetenskaplig fakultet).
    Meiosis and Its Deviations in Polyploid Animals2013Inngår i: Cytogenetic and Genome Research, ISSN 1424-8581, E-ISSN 1424-859X, Vol. 140, nr 2-4, s. 185-203Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    We review the different modes of meiosis and its deviations encountered in polyploid animals. Bisexual reproduction involving normal meiosis occurs in some allopolyploid frogs with variable degrees of polyploidy. Aberrant modes of bisexual reproduction include gynogenesis, where a sperm stimulates the egg to develop. The sperm may enter the egg but there is no fertilization and syngamy. In hybridogenesis, a genome is eliminated to produce haploid or diploid eggs or sperm. Ploidy can be elevated by fertilization with a haploid sperm in meiotic hybridogenesis, which elevates the ploidy of hybrid offspring such that they produce diploid gametes. Polyploids are then produced in the next generation. In kleptogenesis, females acquire full or partial genomes from their partners. In pre-equalizing hybrid meiosis, one genome is transmitted in the Mendelian fashion, while the other is transmitted clonally. Parthenogenetic animals have a very wide range of mechanisms for restoring or maintaining the mother's ploidy level, including gamete duplication, terminal fusion, central fusion, fusion of the first polar nucleus with the product of the first division, and premeiotic duplication followed by a normal meiosis. In apomictic parthenogenesis, meiosis is replaced by what is effectively mitotic cell division. The above modes have different evolutionary consequences, which are discussed. See also the sister article by Grandont et al. in this themed issue.

  • 20. Terhivuo, J.
    et al.
    Halmepuro, A.-M.
    Saura, Anssi
    Umeå universitet, Teknisk-naturvetenskapliga fakulteten, Institutionen för molekylärbiologi (Teknisk-naturvetenskaplig fakultet).
    Clonal diversity and morphometry in the parthenogenetic earthworm Eiseniella tetraedra (Sav.) as affected by habitat characteristics including radioactive pollution2011Inngår i: Pedobiologia, ISSN 0031-4056, E-ISSN 1873-1511, Vol. 54, s. S11-S18Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    Eiseniella tetraedra (Sav.) is a cosmopolitan earthworm reproducing by obligate parthenogenesis. Here, we examined whether habitat characteristics affected the clone pool diversities and morphometric variability of the stenotopic riparian species E. tetraedra along a west-east transect from the Scandinavian mountains to lowland habitats of the Swedish east coast through Finland and to Russia (the Komi Republic) near the Ural Mountains. The transect comprised a geographical distance that cuts through the maritime to continental climatological zones within the boreal forest belt. It terminated in the Komi Republic, thus adding habitat (soil) characteristics to the factor of radioactive pollution. We found that mountain brooks in Sweden hosted the lowest numbers of clones, but in the lowland samples the clone pool diversities decreased in general from Sweden through Finland and Russia, i.e. from west to east. Nevertheless, high levels of clonal variability were observed within the countries, so that even monomorphic pools were found. However, no clones were shared between the countries. The fresh body weights and posterior body lengths of adult earthworms decreased from west to east. The numbers of posterior segments did not, however, differ between the countries, clue to decreased segment size. The location of the clitellum, tubercula pubertatis and male pores showed no clear-cut morphometric clines along the W-E gradient, but the tubercula pubertatis and male pores were more clearly demarcated in adults of the Russian material than in those from the West. Eiseniella adults from the Swedish mountains carried spermatophores considerably more often than those from the other localities. E. tetraedra from localities with radioactive pollution in Russia (the Komi Republic) showed no clear-cut clone pool diversities in comparison to the clone pools of the other sites within the area. Monomorphic clone pools were recorded in localities with low as well as high levels of long-term ionizing radiation and exposure to heavy metals. We found no morphological malformations, such as dislocations of characters, in comparison to individuals from sites with lower levels of environmental radiation.

  • 21. Terhivuo, Juhani
    et al.
    Saura, Anssi
    Umeå universitet, Teknisk-naturvetenskapliga fakulteten, Institutionen för molekylärbiologi (Teknisk-naturvetenskaplig fakultet).
    Clone distribution of the earthworm Eiseniella tetraedra (Sav.) (Oligochaeta: Lumbricidae) across an altitudinal gradient on subarctic mountains of NW Europe2008Inngår i: Pedobiologia, ISSN 0031-4056, E-ISSN 1873-1511, Vol. 51, nr 5-6, s. 375-384Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    In earlier studies, we have shown that clone diversity of the parthenogenetic earthworm Eiseniella tetraedra increases from the upper reaches of rivers in northern Sweden towards their mouths. Now we survey brooks in the Scandes Mountains in the watershed between Sweden and Norway where major rivers originate. Using starch get enzyme electrophoresis, we found 37 clones in a total catch of 379 individuals from six mountains. The most abundant clone made up 48.3% of the individuals collected. It was present on most mountains and was found at different elevations. In comparison with other clones it may represent a general-purpose genotype adapted to environmental conditions ranging from alpine through to subalpine to boreal habitats in the mountains. Diversity of clone assemblages decreased with increasing elevation. On four mountains, one to two clones were found at higher elevations. Passive downstream dispersal of E. tetraedra propagules from wider areas of the mountains was responsible for the more diverse clone pools in the tower reaches of the brooks (i.e., "small rivers behave like large ones"). Two clone groups, which deviated from the norm clone in their number of enzyme variants, were evenly distributed among different elevations. Therefore, we could not correlate genotype differences (i.e., adaptation of clones to mountain elevations). Clone pool similarities among the mountains were tow on average (range 0-58%) but in a cluster of four mountains, similarities varied from 46% to 58%. Clone pool similarities between different elevations of the same mountain ranged from 27% to 83%. One mountain brook was sampled over 3 years to assess clone turnover. Only the norm clone was found in upstream habitats but it and three other clones were recorded downstream in at least 2 years. Ten clones were found once in the latter habitat as well.

  • 22. Terhivuo, Juhani
    et al.
    Saura, Anssi
    Umeå universitet, Teknisk-naturvetenskaplig fakultet, Molekylärbiologi (Teknisk-naturvetenskaplig fakultet).
    Dispersal and clonal diversity of North-European parthenogenetic earthworms.2006Inngår i: Biol Invasions, Vol. 8, s. 1205-18Artikkel i tidsskrift (Fagfellevurdert)
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