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Saura, Anssi
Alternative names
Publications (10 of 22) Show all publications
Saura, A. (2014). A tale of two papers. Hereditas, 151(6), 119-122
Open this publication in new window or tab >>A tale of two papers
2014 (English)In: Hereditas, ISSN 0018-0661, E-ISSN 1601-5223, Vol. 151, no 6, p. 119-122Article in journal (Refereed) Published
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.

National Category
History of Ideas Genetics
Identifiers
urn:nbn:se:umu:diva-100155 (URN)10.1111/hrd2.00073 (DOI)000348573000004 ()25588299 (PubMedID)
Available from: 2015-02-26 Created: 2015-02-24 Last updated: 2018-06-07Bibliographically approved
Savolainen, E., Drotz, M. K., Saura, A. & Stahls, G. (2014). Baetis bundyae (Ephemeroptera: Baetidae), described from Arctic Canada is found in northernmost Europe. Canadian Entomologist, 146(6), 621-629
Open this publication in new window or tab >>Baetis bundyae (Ephemeroptera: Baetidae), described from Arctic Canada is found in northernmost Europe
2014 (English)In: Canadian Entomologist, ISSN 0008-347X, E-ISSN 1918-3240, Vol. 146, no 6, p. 621-629Article in journal (Refereed) Published
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.

National Category
Medical and Health Sciences
Identifiers
urn:nbn:se:umu:diva-98555 (URN)10.4039/tce.2014.21 (DOI)000345121600005 ()
Available from: 2015-01-30 Created: 2015-01-23 Last updated: 2018-06-07Bibliographically approved
Saura, A., Von Schoultz, B., Saura, A. O. & Brown, K. S. . (2013). Chromosome evolution in Neotropical butterflies. Hereditas, 150(2-3), 26-37
Open this publication in new window or tab >>Chromosome evolution in Neotropical butterflies
2013 (English)In: Hereditas, ISSN 0018-0661, E-ISSN 1601-5223, Vol. 150, no 2-3, p. 26-37Article in journal (Refereed) Published
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.

National Category
Natural Sciences
Identifiers
urn:nbn:se:umu:diva-79442 (URN)10.1111/j.1601-5223.2013.00008.x (DOI)000321962600002 ()
Available from: 2013-08-21 Created: 2013-08-19 Last updated: 2018-06-08Bibliographically approved
Stenberg, P. & Saura, A. (2013). Meiosis and Its Deviations in Polyploid Animals. Cytogenetic and Genome Research, 140(2-4), 185-203
Open this publication in new window or tab >>Meiosis and Its Deviations in Polyploid Animals
2013 (English)In: Cytogenetic and Genome Research, ISSN 1424-8581, E-ISSN 1424-859X, Vol. 140, no 2-4, p. 185-203Article in journal (Refereed) Published
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.

Keywords
Gynogenesis, Hybridogenesis, Kleptogenesis, Parthenogenesis
National Category
Cell and Molecular Biology
Identifiers
urn:nbn:se:umu:diva-79922 (URN)10.1159/000351731 (DOI)000322770900008 ()
Available from: 2013-09-04 Created: 2013-09-04 Last updated: 2018-06-08Bibliographically approved
Brown, K. S. ., von Schoultz, B., Saura, A. O. & Saura, A. (2012). Chromosomal evolution in the South American Riodinidae (Lepidoptera Papilionoidea). Hereditas, 149(4), 128-138
Open this publication in new window or tab >>Chromosomal evolution in the South American Riodinidae (Lepidoptera Papilionoidea)
2012 (English)In: Hereditas, ISSN 0018-0661, E-ISSN 1601-5223, Vol. 149, no 4, p. 128-138Article in journal (Refereed) Published
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.

National Category
Genetics
Identifiers
urn:nbn:se:umu:diva-60656 (URN)10.1111/j.1601-5223.2012.02250.x (DOI)000308639600002 ()
Available from: 2012-10-26 Created: 2012-10-22 Last updated: 2018-06-08Bibliographically approved
Drotz, M. K., Brodin, T., Saura, A. & Giles, B. E. (2012). Ecotype Differentiation in the Face of Gene Flow within the Diving Beetle Agabus bipustulatus (Linnaeus, 1767) in Northern Scandinavia. PLoS ONE, 7(2), e31381
Open this publication in new window or tab >>Ecotype Differentiation in the Face of Gene Flow within the Diving Beetle Agabus bipustulatus (Linnaeus, 1767) in Northern Scandinavia
2012 (English)In: PLoS ONE, ISSN 1932-6203, E-ISSN 1932-6203, Vol. 7, no 2, p. e31381-Article in journal (Refereed) Published
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.

National Category
Ecology
Identifiers
urn:nbn:se:umu:diva-55396 (URN)10.1371/journal.pone.0031381 (DOI)000302733900044 ()
Available from: 2012-05-15 Created: 2012-05-14 Last updated: 2018-06-08Bibliographically approved
Drotz, M. K., Savolainen, E., Saura, A. & Stahls, G. (2012). The genetic population structure of lotic and lentic mayflies of the Baetis vernus group (Ephemeroptera: Baetidae). Canadian Entomologist, 144(5), 679-690
Open this publication in new window or tab >>The genetic population structure of lotic and lentic mayflies of the Baetis vernus group (Ephemeroptera: Baetidae)
2012 (English)In: Canadian Entomologist, ISSN 0008-347X, E-ISSN 1918-3240, Vol. 144, no 5, p. 679-690Article in journal (Refereed) Published
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.

National Category
Biochemistry and Molecular Biology
Identifiers
urn:nbn:se:umu:diva-61173 (URN)10.4039/tce.2012.69 (DOI)000309114800007 ()
Available from: 2012-11-09 Created: 2012-11-07 Last updated: 2018-06-08Bibliographically approved
Terhivuo, J., Halmepuro, A.-M. & Saura, A. (2011). Clonal diversity and morphometry in the parthenogenetic earthworm Eiseniella tetraedra (Sav.) as affected by habitat characteristics including radioactive pollution. Paper presented at 9th International Symposium on Earthworm Ecology, Xalapa, Veracruz, Mexico, 5th – 10th September 2010. Pedobiologia, 54, S11-S18
Open this publication in new window or tab >>Clonal diversity and morphometry in the parthenogenetic earthworm Eiseniella tetraedra (Sav.) as affected by habitat characteristics including radioactive pollution
2011 (English)In: Pedobiologia, ISSN 0031-4056, E-ISSN 1873-1511, Vol. 54, p. S11-S18Article in journal (Refereed) Published
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.

Keywords
Earthworm, Eiseniella tetraedra, Parthenogenesis, Clone, Morphological characters, Environmental radiation
National Category
Soil Science Biological Sciences
Identifiers
urn:nbn:se:umu:diva-61486 (URN)10.1016/j.pedobi.2011.08.009 (DOI)000300211300003 ()
Conference
9th International Symposium on Earthworm Ecology, Xalapa, Veracruz, Mexico, 5th – 10th September 2010
Note

Supplement 1

Available from: 2012-11-15 Created: 2012-11-15 Last updated: 2018-06-08Bibliographically approved
Stenberg, P. & Saura, A. (2009). Cytology of Asexual Animals. In: Isa Schön, Koen Martens, Peter Dijk (Ed.), Lost Sex: The Evolutionary Biology of Parthenogenesis (pp. 63-74). Dordrecht: Springer Netherlands
Open this publication in new window or tab >>Cytology of Asexual Animals
2009 (English)In: Lost Sex: The Evolutionary Biology of Parthenogenesis / [ed] Isa Schön, Koen Martens, Peter Dijk, Dordrecht: Springer Netherlands, 2009, p. 63-74Chapter in book (Other academic)
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.

Place, publisher, year, edition, pages
Dordrecht: Springer Netherlands, 2009
National Category
Evolutionary Biology Zoology Botany Ecology
Identifiers
urn:nbn:se:umu:diva-76155 (URN)10.1007/978-90-481-2770-2_4 (DOI)000283623900004 ()978-90-481-2769-6 (ISBN)978-90-481-2770-2 (ISBN)
Available from: 2013-07-05 Created: 2013-07-04 Last updated: 2018-06-08Bibliographically approved
Terhivuo, J. & Saura, A. (2008). Clone distribution of the earthworm Eiseniella tetraedra (Sav.) (Oligochaeta: Lumbricidae) across an altitudinal gradient on subarctic mountains of NW Europe. Pedobiologia, 51(5-6), 375-384
Open this publication in new window or tab >>Clone distribution of the earthworm Eiseniella tetraedra (Sav.) (Oligochaeta: Lumbricidae) across an altitudinal gradient on subarctic mountains of NW Europe
2008 (English)In: Pedobiologia, ISSN 0031-4056, E-ISSN 1873-1511, Vol. 51, no 5-6, p. 375-384Article in journal (Refereed) Published
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.

Place, publisher, year, edition, pages
Jena: Elsevier, 2008
Keywords
lumbricidae, earthworm, Eiseniella tetraedra, clone, parthenogenesis
National Category
Ecology Soil Science Environmental Sciences related to Agriculture and Land-use
Identifiers
urn:nbn:se:umu:diva-117531 (URN)10.1016/j.pedobi.2007.10.001 (DOI)000255499300006 ()
Available from: 2016-03-01 Created: 2016-03-01 Last updated: 2018-06-07Bibliographically approved
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