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  • 301.
    Jakobsson, M.
    et al.
    Department of Cell and Organism Biology, Genetics, Lund University.
    Säll, T.
    Department of Cell and Organism Biology, Genetics, Lund University.
    Lind-Halldén, Christina
    Kristianstad University, Department of Mathematics and Science.
    Halldén, Christer
    Department of Clinical Chemistry, Malmö University Hospital.
    The evolutionary history of the common chloroplast genome of Arabidopsis thaliana and A. suecica2007In: Journal of Evolutionary Biology, ISSN 1010-061X, E-ISSN 1420-9101, Vol. 20, no 1, p. 104-121Article in journal (Refereed)
    Abstract [en]

    The evolutionary history of the common chloroplast (cp) genome of the allotetraploid Arabidopsis suecica and its maternal parent A. thaliana was investigated by sequencing 50 fragments of cpDNA, resulting in 98 polymorphic sites. The variation in the A. suecica sample was small, in contrast to that of the A. thaliana sample. The time to the most recent common ancestor (T(MRCA)) of the A. suecica cp genome alone was estimated to be about one 37th of the T(MRCA) of both the A. thaliana and A. suecica cp genomes. This corresponds to A. suecica having a MRCA between 10 000 and 50 000 years ago, suggesting that the entire species originated during, or before, this period of time, although the estimates are sensitive to assumptions made about population size and mutation rate. The data was also consistent with the hypothesis of A. suecica being of single origin. Isolation-by-distance and population structure in A. thaliana depended upon the geographical scale analysed; isolation-by-distance was found to be weak on the global scale but locally pronounced. Within the genealogical cp tree of A. thaliana, there were indications that the root of the A. suecica species is located among accessions of A. thaliana that come primarily from central Europe. Selective neutrality of the cp genome could not be rejected, despite the fact that it contains several completely linked protein-coding genes.

  • 302.
    Jakobsson, Mattias
    et al.
    Bioinformatics Program, Department of Human Genetics, University of Michigan.
    Hagenblad, Jenny
    Department of Biology, Linköping University.
    Tavaré, Simon
    Molecular and Computational Biology, University of Southern California.
    Säll, Torbjörn
    Department of Cell and Organism Biology, Genetics, Lund University.
    Halldén, Christer
    Department of Clinical Chemistry, Malmö University Hospital.
    Lind-Halldén, Christina
    Kristianstad University, Department of Mathematics and Science.
    Nordborg, Magnus
    Molecular and Computational Biology, University of Southern California.
    A unique recent origin of the allotetraploid species Arabidopsis suecica: evidence from nuclear DNA markers2006In: Molecular biology and evolution, ISSN 0737-4038, E-ISSN 1537-1719, Vol. 23, no 6, p. 1217-1231Article in journal (Refereed)
    Abstract [en]

    A coalescent-based method was used to investigate the origins of the allotetraploid Arabidopsis suecica, using 52 nuclear microsatellite loci typed in eight individuals of A. suecica and 14 individuals of its maternal parent Arabidopsis thaliana, and four short fragments of genomic DNA sequenced in a sample of four individuals of A. suecica and in both its parental species A. thaliana and Arabidopsis arenosa. All loci were variable in A. thaliana but only 24 of the 52 microsatellite loci and none of the four sequence fragments were variable in A. suecica. We explore a number of possible evolutionary scenarios for A. suecica and conclude that it is likely that A. suecica has a recent, unique origin between 12,000 and 300,000 years ago. The time estimates depend strongly on what is assumed about population growth and rates of mutation. When combined with what is known about the history of glaciations, our results suggest that A. suecica originated south of its present distribution in Sweden and Finland and then migrated north, perhaps in the wake of the retreating ice.

  • 303.
    Jamell, Sanna
    Kristianstad University, School of Education and Environment.
    Differences in desiccation and freezing tolerance in limnic and limno-terrestrial tardigrades2015Independent thesis Advanced level (degree of Master (One Year)), 20 credits / 30 HE creditsStudent thesis
    Abstract [en]

    Tardigrades are microscopic aquatic invertebrates that are known for their ability to survive extreme conditions. Different species of tardigrades tolerate extreme conditions to a varying degree. It has been suggested that limnic tardigrades would have a lower tolerance to desiccation compared to limno-terrestrial tardigrades. In this study limno-terrestrial species Ramazzottius oberhaeuseri and the limnic species Hypsibius dujardini is compared in regard to their tolerance to desiccation and freezing. The results show that there indeed is a difference in the tolerance and that Ramazzottius oberhaeuseri show better tolerance.

  • 304.
    Johanna, Grönroos
    et al.
    Kristianstad University, School of Education and Environment, Avdelningen för Naturvetenskap. Kristianstad University, Research environment Man & Biosphere Health (MABH).
    Alerstam, Thomas
    Lunds universitet.
    Green, Martin
    Lunds universitet.
    Orientation of shorebirds in relation to wind: both drift and compensation in the same region2013In: Journal of Ornithology, ISSN 2193-7192, E-ISSN 2193-7206, Vol. 154, p. 385-392Article in journal (Refereed)
    Abstract [en]

    Migratorymovements in air or water are strongly affected by wind and ocean currents and an animal which does not compensate for lateral flow will be drifted from its intended direction of movement. We investigated whether arctic shorebirds during autumn migration in the region of South Sweden and the southern Baltic Sea compensate for wind drift or allow themselves to be drifted when approaching a known goal area under different circumstances (over sea, over land, at low and high altitude) using two different approaches, visual telescope observations and tracking radar. The shorebirds showed clearly different responses to crosswinds along this short section (\200 km) of the migratory journey, from almost full drift when departing over the sea, followed by partial drift and almost full compensation at higher altitudes over land during later stages. Our study demonstrates that shorebirds are also remarkably variable in their response to crosswinds during short sections of their migratory journey. The recorded initial drift close to departure is probably not adaptive but rather a result of constraints in the capacity of the birds to compensate in some situations, e.g. in low-altitude climbing flight over the sea. We found no difference in orientation response to wind between adult and juvenile birds. This study indicates, in addition to adaptive orientation responses to wind, the importance of the nonadaptive wind drift that contributes to increasing the variability of drift/compensation behaviour between places that are separated by only short distances, depending on the local topographic and environmental conditions.

  • 305.
    Johanna, Grönroos
    et al.
    Lunds universitet.
    Green, Martin
    Lunds universitet.
    Alerstam, Thomas
    Lunds universitet.
    To fly or not to fly depending on winds: shorebird migration in different seasonal wind regimes2012In: Animal Behaviour, ISSN 0003-3472, E-ISSN 1095-8282, Vol. 83, no 6, p. 1449-1457Article in journal (Refereed)
    Abstract [en]

    Migratory birds are predicted to adapt their departure to wind, changing their threshold of departure and selectivity of the most favourable winds in relation to the mean, scatter and skewness of the wind regime. The optimal departure behaviour depends also on the importance of time and energy minimization during migration and on the ratio of cost of flight to cost of resting and waiting for more favourable winds. We compared departure and flight activity of shorebirds migrating in contrasting wind regimes during autumn (high probability of wind resistance) and spring (high probability of wind assistance) in southern Scandinavia, using data obtained by radiotelemetry, radar tracking and visual observations. The shorebirds changed their threshold for departure in relation to wind between the two seasons, flying almost exclusively with wind assistance in spring but regularly with wind resistance during autumn. The degree of wind selectivity in relation to the distributions of available wind effects was similar during autumn and spring indicating that reducing time and energy costs for migration was important during both seasons. These results demonstrate that migratory birds change departure behaviour in relation to the prevailing wind regime. It remains unknown whether they change behaviour not only seasonally but also in different zones along the migration route and whether they respond to differences not only in mean wind conditions but also in scatter and skewness between wind regimes. Our study indicates the possible existence of an adaptive flexibility in responses to wind regimes among migratory birds. (c) 2012 The Association for the Study of Animal Behaviour. Published by Elsevier Ltd. All rights reserved.

  • 306.
    Johanna, Grönroos
    et al.
    Lunds universitet.
    Muheim, Rachel
    Lunds universitet.
    Akesson, Susanne
    Lunds universitet.
    Orientation and autumn migration routes of juvenile sharp- tailed sandpipers at a staging site in Alaska2010In: Journal of Experimental Biology, ISSN 0022-0949, E-ISSN 1477-9145, Vol. 213, no 11, p. 1829-1835Article in journal (Refereed)
    Abstract [en]

    Arctic waders are well known for their impressive long-distance migrations between their high northerly breeding grounds and wintering areas in the Southern hemisphere. Performing such long migrations requires precise orientation mechanisms. We conducted orientation cage experiments with juvenile sharp-tailed sandpipers (Calidris acuminata) to investigate what cues they rely on when departing from Alaska on their long autumn migration flights across the Pacific Ocean to Australasia, and which possible migration routes they could use. Experiments were performed under natural clear skies, total overcast conditions and in manipulated magnetic fields at a staging site in Alaska. Under clear skies the juvenile sharp-tailed sandpipers oriented towards SSE, which coincides well with reported sun compass directions from their breeding grounds in Siberia towards Alaska and could reflect their true migratory direction towards Australasia assuming that they change direction towards SW somewhere along the route. Under overcast skies the sandpipers showed a mean direction towards SW which would lead them to Australasia, if they followed a sun compass route. However, because of unfavourable weather conditions (headwinds) associated with overcast conditions, these south-westerly directions could also reflect local movements. The juvenile sharp-tailed sandpipers responded clearly to the manipulated magnetic field under overcast skies, suggesting the use of a magnetic compass for selecting their courses.

  • 307.
    Jonsson, Lars J.
    Kristianstad University, School of Education and Environment, Avdelningen för Naturvetenskap. Kristianstad University, Research environment Man & Biosphere Health (MABH).
    Atlantplattfoting Polydesmus angustus - en för Sverige ny plattfoting2010In: Fauna och flora : populär tidskrift för biologi, ISSN 0014-8903, Vol. 105, no 1, p. 34-37Article in journal (Other academic)
  • 308.
    Jonsson, Lars J.
    Kristianstad University, School of Education and Environment, Avdelningen för Naturvetenskap. Kristianstad University, Research environment Man & Biosphere Health (MABH).
    Dvärgspindeln Baryphyma pratense (Blackw.) funnen i Sverige2004In: Fazett, ISSN 1100-2425, Vol. 17, no 2, p. 39-41Article in journal (Other academic)
  • 309.
    Jonsson, Lars J.
    Kristianstad University, School of Education and Environment, Avdelningen för Naturvetenskap. Kristianstad University, Research environment Man & Biosphere Health (MABH).
    Grenlocke Dicranopalpus ramosus -en för Sverige ny art av lockespindel2013In: Fauna och flora : populär tidskrift för biologi, ISSN 0014-8903, Vol. 108, no 1, p. 18-21Article in journal (Other academic)
  • 310.
    Jonsson, Lars J.
    Lund.
    Nachweis von Uloborus plumipes in einem Gewächshaus in Niedersachsen: A report on Uloborus plumipes from a greenhouse in Lower Saxony1993In: Arachnologische Mitteilungen, ISSN 1018-4171, no 6, p. 42-43Article in journal (Other academic)
  • 311.
    Jonsson, Lars J.
    Kristianstad University, School of Education and Environment, Avdelningen för Naturvetenskap. Kristianstad University, Research environment Man & Biosphere Health (MABH).
    Några intressanta spindelfynd från Gotland2002In: Fazett, ISSN 1100-2425, Vol. 15, no 2, p. 35-40Article in journal (Other academic)
  • 312.
    Jonsson, Lars J.
    Lund.
    Spiders of the Skäralid Gorge, southernmost Sweden1998In: Proceedings of the 17th European Colloquium of Arachnology, Edinburgh 1997 / [ed] P. A. Selden, British Arachnological Society, 1998, p. 273-276Conference paper (Refereed)
    Abstract [en]

    The spider fauna of the Skäralid Gorge, in southernmost Sweden, was investigated in 1994 and 1995. Nine stations in partially different biotopes were sampled with pitfall traps. Trees, bushes and cliffs were also investigated by various methods. The slopes and screes are sparsely populated. However, in most biotopes diversity is rather high. On the northern slopes and in the bottom of the gorge some cold-adapted northern species are found. In the rather dark, shaded and, moist bottom of the gorge live typical forest species, including some rare spiders such as Robertus neglectus, Lepthyphantes angulatus, Diplocentria bidentata and Coelotes atropos. The sunny slopes have the most interesting spider fauna, with rich populations of Atypus affinis, Pardosa alacris, Liocranum rupicola, Zelotes subterraneus, Scotina celans, and Sitticus pubescens. Three species of Pardosa lugubris s.l. live in Skäralid: P. lugubris s.s. in the shaded, forested parts, P. saltans on partially shaded slopes and P. alacris in sunnier and stonier parts of the southern slopes. On trees and bushes on the slopes some thermophilous species can be found, such as Araniella inconspicua. 

  • 313. Jonsson, Lars J.
    Spindlar på och i hus1996In: Fazett, ISSN 1100-2425, Vol. 9, no 2, p. 17-23Article in journal (Other academic)
  • 314.
    Jonsson, Lars J.
    Lund.
    Taggspindeln Cheiracanthium elegans, ny för Nordeuropa, med en kort översikt av släktets svenska arter1995In: Entomologisk Tidskrift, ISSN 0013-886X, Vol. 116, no 1-2, p. 55-58Article in journal (Other academic)
  • 315.
    Jonsson, Lars J.
    Lund.
    The distribution and habitat of Pocadicnemis and P. juncea (Araneae, Linyphiidae) in Sweden1995In: Arachnologische Mitteilungen, ISSN 1018-4171, Vol. 9, p. 46-48Article in journal (Refereed)
  • 316.
    Jonsson, Lars J.
    Lund.
    Tofsspindeln - en spindelart som invaderat Europas växthus1998In: Fauna och flora : populär tidskrift för biologi, ISSN 0014-8903, Vol. 93, no 3, p. 119-124Article in journal (Other academic)
  • 317.
    Jonsson, Lars J.
    Lund.
    Tre för Sverige nya spindelarter (Araneae)1990In: Entomologisk Tidskrift, ISSN 0013-886X, Vol. 111, no 3, p. 83-86Article in journal (Other academic)
  • 318.
    Jonsson, Lars J.
    et al.
    Kristianstad University, School of Education and Environment, Avdelningen för Naturvetenskap. Kristianstad University, Research environment Man & Biosphere Health (MABH).
    Andersson, Pia
    Spindlar och lockespindlar funna på Lilla Karlsö2008In: Körkmacken, Vol. 49, p. 14-16Article in journal (Other academic)
  • 319.
    Jonsson, Lars J.
    et al.
    Kristianstad University, School of Education and Environment, Avdelningen för Naturvetenskap. Kristianstad University, Research environment Man & Biosphere Health (MABH).
    Bergsten, Johannes
    Spindelfynd från Umetrakten med en komprimerad lista över Sveriges spindlar2005In: Natur i Norr, ISSN 0280-5618, Vol. 24, no 2, p. 97-102Article in journal (Other academic)
  • 320. Jourdain, Elsa
    et al.
    Gunnarsson, Gunnar
    Kristianstad University, School of Teacher Education.
    Wahlgren, John
    Latorre-Magalef, Neus
    Bröjer, Caroline
    Sahlin, Sofie
    Svensson, Lovisa
    Waldenström, Jonas
    Lundkvist, Åke
    Falk, Kerstin
    Olsen, Björn
    Experimental infection of mallards (Anas platyrhynchos) with low pathogenic avian influenza viruses: successive challenges with homologous and heterologous subtypes2009Conference paper (Refereed)
  • 321.
    Jourdain, Elsa
    et al.
    Section for Zoonotic Ecology and Epidemiology, School of Natural Sciences, Linnaeus University, Kalmar.
    Gunnarsson, Gunnar
    Kristianstad University, School of Teacher Education.
    Wahlgren, John
    Karolinska Institutet, Microbiology & Tumor Biology Center (MTC), Stockholm.
    Latorre-Margalef, Neus
    Section for Zoonotic Ecology and Epidemiology, School of Natural Sciences, Linnaeus University, Kalmar.
    Bröjer, Caroline
    National Veterinary Institute, Uppsala.
    Sahlin, Sofie
    Karolinska Institutet, Microbiology & Tumor Biology Center (MTC), Stockholm.
    Svensson, Lovisa
    Section for Zoonotic Ecology and Epidemiology, School of Natural Sciences, Linnaeus University, Kalmar.
    Waldenström, Jonas
    Section for Zoonotic Ecology and Epidemiology, School of Natural Sciences, Linnaeus University, Kalmar.
    Lundkvist, Åke
    Swedish Institute for Infectious Disease Control, Stockholm.
    Olsen, Björn
    Section for Zoonotic Ecology and Epidemiology, School of Natural Sciences, Linnaeus University, Kalmar.
    Influenza virus in a natural host, the Mallard: experimental infection data2010In: PLoS One, ISSN 1932-6203, Vol. 5, no 1, p. e8935-Article in journal (Refereed)
    Abstract [en]

    Wild waterfowl, particularly dabbling ducks such as mallards (Anas platyrhynchos), are considered the main reservoir of low-pathogenic avian influenza viruses (LPAIVs). They carry viruses that may evolve and become highly pathogenic for poultry or zoonotic. Understanding the ecology of LPAIVs in these natural hosts is therefore essential. We assessed the clinical response, viral shedding and antibody production of juvenile mallards after intra-esophageal inoculation of two LPAIV subtypes previously isolated from wild congeners. Six ducks, equipped with data loggers that continually monitored body temperature, heart rate and activity, were successively inoculated with an H7N7 LPAI isolate (day 0), the same H7N7 isolate again (day 21) and an H5N2 LPAI isolate (day 35). After the first H7N7 inoculation, the ducks remained alert with no modification of heart rate or activity. However, body temperature transiently increased in four individuals, suggesting that LPAIV strains may have minor clinical effects on their natural hosts. The excretion patterns observed after both re-inoculations differed strongly from those observed after the primary H7N7 inoculation, suggesting that not only homosubtypic but also heterosubtypic immunity exist. Our study suggests that LPAI infection has minor clinically measurable effects on mallards and that mallard ducks are able to mount immunological responses protective against heterologous infections. Because the transmission dynamics of LPAIVs in wild populations is greatly influenced by individual susceptibility and herd immunity, these findings are of high importance. Our study also shows the relevance of using telemetry to monitor disease in animals.

  • 322.
    Järhult, Josef D.
    et al.
    Section of Infectious Diseases, Department of Medical Sciences, Uppsala University.
    Muradrasoli, Shaman
    Section of Bacteriology and Food Safety, Department of.
    Wahlgren, John
    Swedish Institute for Infectious Disease Control and Karolinska Institute.
    Söderström, Hanna
    Department of Chemistry, Umeå University.
    Orozovic, Goran
    Section for Zoonotic Ecology and Epidemiology, School of Natural Sciences, Linnaeus University, Kalmar.
    Gunnarsson, Gunnar
    Kristianstad University, School of Education and Environment.
    Bröjer, Caroline
    National Veterinary Institute, Uppsala.
    Latorre-Margalef, Neus
    Section for Zoonotic Ecology and Epidemiology, School of Natural Sciences, Linnaeus University, Kalmar.
    Fick, Jerker
    Department of Chemistry, Umeå University.
    Grabic, Roman
    Department of Chemistry, Umeå University.
    Lennerstrand, Johan
    Section of Clinical Virology, Department of Medical Sciences, Uppsala University.
    Waldenström, Jonas
    Section for Zoonotic Ecology and Epidemiology, School of Natural Sciences, Linnaeus University, Kalmar.
    Lundkvist, Åke
    Swedish Institute for Infectious Disease Control and Karolinska Institute.
    Olsen, Björn
    Section of Infectious Diseases, Department of Medical Sciences, Uppsala University.
    Environmental levels of the antiviral oseltamivir induce development of resistance mutation H274Y in influenza A/H1N1 Virus in mallards2011In: PLoS ONE, ISSN 1932-6203, E-ISSN 1932-6203, Vol. 6, no 9, p. e24742-Article in journal (Refereed)
    Abstract [en]

    Oseltamivir (Tamiflu) is the most widely used drug against influenza infections and is extensively stockpiled worldwide as part of pandemic preparedness plans. However, resistance is a growing problem and in 2008–2009, seasonal human influenza A/H1N1 virus strains in most parts of the world carried the mutation H274Y in the neuraminidase gene which causes resistance to the drug. The active metabolite of oseltamivir, oseltamivir carboxylate (OC), is poorly degraded in sewage treatment plants and surface water and has been detected in aquatic environments where the natural influenza reservoir, dabbling ducks, can be exposed to the substance. To assess if resistance can develop under these circumstances, we infected mallards with influenza A/H1N1 virus and exposed the birds to 80 ng/L, 1 mg/L and 80m g/L of OC through their sole water source. By sequencing the neuraminidase gene from fecal samples, we found that H274Y occurred at 1 mg/L of OC and rapidly dominated the viral population at 80 mg/L. IC50 for OC was increased from 2–4 nM in wild-type viruses to 400–700 nM in H274Y mutants as measured by a neuraminidase inhibition assay. This is consistent with the decrease in sensitivity to OC that has been noted among human clinical isolates carrying H274Y. Environmental OC levels have been measured to 58–293 ng/L during seasonal outbreaks and are expected to reach mg/L-levels during pandemics. Thus, resistance could be induced in influenza viruses circulating among wild ducks. As influenza viruses can cross species barriers, oseltamivir resistance could spread to human-adapted strains with pandemic potential disabling oseltamivir, a cornerstone in pandemic preparedness planning. We propose surveillance in wild birds as a measure to understand the resistance situation in nature and to monitor it over time. Strategies to lower environmental levels of OC include improved sewage treatment and, more importantly, a prudent use of antivirals.

  • 323.
    Jönsson, Ingemar
    et al.
    Kristianstad University, School of Education and Environment, Avdelningen för Naturvetenskap. Kristianstad University, Forskningsmiljön Man and Biosphere Health (MABH).
    Beltran-Pardo, Eliana
    Pontificia Universidad Javeriana, Instituto de Genética Humana, Bogotá.
    Haghdoost, Siamak
    Department of Molecular Biosciences, The Wenner-Gren Institute, Stockholm University.
    Wojcik, Andrzej
    Department of Molecular Biosciences, The Wenner-Gren Institute, Stockholm University.
    Bermúdez-Cruz, Rosa María
    Centro de Investigación y Estudios Avanzados del Instituto Politécnico Nacional - CINVESTAV, Mexico City.
    Bernal Villegas, Jaime E.
    Pontificia Universidad Javeriana, Instituto de Genética Humana, Bogotá.
    Harms-Ringdahl, Mats
    Department of Molecular Biosciences, The Wenner-Gren Institute, Stockholm University.
    Tolerance to gamma-irradiation in eggs of the tardigrade Richtersius coronifer depends on stage of development2013In: Journal of limnology, ISSN 1129-5767, E-ISSN 1723-8633, Vol. 72, no s1, p. 73-79Article in journal (Refereed)
    Abstract [en]

    Tardigrades are known as one of the most radiation tolerant animals on Earth, and several studies on tolerance in adult tardigrades have been published. In contrast, very few studies on radiation tolerance of embryonic stages have been reported. Here we report a study on tolerance to gamma irradiation in eggs of the eutardigrade Richtersius coronifer. Irradiation of eggs collected directly from a natural substrate (moss) showed a clear dose-response, with a steep decline in hatchability at doses up to 0.4 kGy followed by a relatively constant hatchability around 25% up to 2 kGy, and a decline to ca. 5% at 4 kGy above which no eggs hatched. Analysis of the time required for eggs to hatch after irradiation (residual development time) showed that hatching of eggs after exposure to high doses of gamma radiation was associated with short residual development time. Since short residual development time means that the egg was irradiated at a late developmental stage, this suggests that eggs were more tolerant to radiation late in development. This was also confirmed in another experiment in which stage of development at irradiation was controlled. No eggs irradiated at the early developmental stage hatched, and only one egg at middle stage hatched, while eggs irradiated in the late stage hatched at a rate indistinguishable from controls. This suggests that the eggs are more sensitive to radiation in the early stages of development, or that tolerance to radiation is acquired only late in development, shortly before the eggs hatch, hypotheses that are not mutually exclusive. Our study emphasizes the importance of considering specific cell cycle phases and developmental stages in studies of tolerance to radiation in tardigrades, and the potential importance of embryonic studies in revealing the mechanisms behind the radiation tolerance of tardigrades and other cryptobiotic animals.

  • 324.
    Jönsson, K. Ingemar
    Lund University.
    Björndjur2001In: Biologen, ISSN 0345-1127, no 1, p. 43-47Article in journal (Other (popular science, discussion, etc.))
  • 325.
    Jönsson, K. Ingemar
    Lund University.
    Djuret som pendlar mellan liv och död2001In: Finlands natur, ISSN 0356-4509, no 3, p. 22-24Article in journal (Other (popular science, discussion, etc.))
  • 326.
    Jönsson, K. Ingemar
    Lund University.
    Inget liv utan vatten2001In: Forskning och framsteg, ISSN 0015-7937, no 6, p. 59-Article in journal (Other (popular science, discussion, etc.))
  • 327.
    Jönsson, K. Ingemar
    Lunds universitet.
    On the disparate terminological use of the concept cryptobiosis2004In: Journal of Fish Diseases, ISSN 0140-7775, E-ISSN 1365-2761, Vol. 27, no 3, p. 175-176Article in journal (Refereed)
    Abstract [en]

    Conceptual and terminological consistency is an important component of science, promoting clarity and preventing confusion. Scientists should therefore always try to avoid giving different meanings to the same term. Apart from this general aspect, multiple definitions of a single term also give rise to practical problems, particularly in connection with literature search. In this note, I will bring attention to a term, cryptobiosis, that has relatively recently appeared in the field of fish disease research, but which has a much longer history and use in a completely different area.

    The concept of cryptobiosis was introduced by Keilin (1959) and defined as ‘the state of an organism when it shows no visible signs of life and when its metabolic activity becomes hardly measurable, or comes reversibly to a standstill’ (Keilin 1959, p. 166). Cryptobiosis replaced the earlier term anabiosis, and is today generally accepted as the common term for different ametabolic life forms (e.g. Clegg 2001; Wright 2001). Cryptobiosis means ‘hidden life’, an appropriate name for a state in which all traditional attributes of life (metabolism, reproduction, DNA replication) are absent. Cryptobiotic life forms have been documented in a variety of organisms, including both plants and animals, but in the latter category mainly among invertebrates (Wright, Westh & Ramløv 1992). Cryptobiosis is commonly induced by desiccation (so-called anhydrobiosis; e.g. Keilin 1959; Jönsson 2001), and aquatic invertebrates such as rotifers, nematodes and tardigrades living in microhabitats exposed to rapid desiccation frequently enter a cryptobiotic state. The research field dealing with cryptobiotic, sensu ametabolic, life forms has expanded considerably during the last 30 years, to a large extent fuelled by the detection of the ability of the disaccharide trehalose to protect dry and frozen biological cells (Crowe 2002).

    More recently, a completely different use of the term cryptobiosis has appeared in the literature on fish disease. In this literature, the term refers to infections of fish by biflagellated protozoa of the genus Cryptobia. Because of the economic importance of salmonid fish, much of the Cryptobia research has focused on Cryptobia salmositica (Katz) that infects salmonids (Woo 2001). The origin of the term cryptobiosis within fish pathology and studies of Cryptobia is unclear, but the earliest record of the term that I have found is Obradovic & Fijan (1979) who used it in a paper on chemotherapeutic treatment against Cryptobia in carp. From 1987 onwards, Woo et al. have used the term frequently (e.g. Woo, Leatherland & Lee 1987; Woo 1987, 1998, 2001), but apparently without any comments on the original proposal of the term. Curiously, few other researchers on Cryptobia seem to have adopted the cryptobiosis terminology, at least as judged from an examination of published titles. Other authors have instead used the expression ‘infections by Cryptobia’. Although using cryptobiosis as a term for infections by Cryptobia is consistent with the rule of creating names for infectious diseases by putting -osis as a post-fix to the name of the infecting organism, in the current case it creates terminological confusion.

    The problems of using the term cryptobiosis in several unrelated fields are obvious. A title such as ‘The biology of cryptobiosis’ would attract the attention of many students interested in ametabolic life forms. They would be disappointed, however, if the paper turned out to be about Cryptobia infection biology. Similarly, fish biologists would find the publication irrelevant to their research if it were properly confined to ametabolic life forms.

    Because ‘cryptobiosis’ as a term for ametabolic life forms is well established and has been used for more than 40 years, it should have priority over the more recent and limited use within fish pathology. I therefore hope that fish pathologists will avoid using the term cryptobiosis and instead use ‘infections by Cryptobia’, ‘cryptobiasis’ or some other term that does not interfere with already established terminology.

  • 328.
    Jönsson, K. Ingemar
    Lund University.
    Population density and species composition of moss-living tardigrades in a boreo-nemoral forest2003In: Ecography, ISSN 0906-7590, E-ISSN 1600-0587, Vol. 26, no 3, p. 356-364Article in journal (Refereed)
    Abstract [en]

    This study investigates for the first time the tardigrade fauna in a variety of different mosses from a coniferous forest and an adjacent clear-cut area in southern Sweden. Tardigrades were found in a majority of the samples. Sixteen species were recorded, of which the cosmopolitan species Macrobiotus hufelandi was the far most common. Some mosses, particularly species with "wefts" growth form, contained more tardigrades than other mosses, indicating that growth form may have an impact on tardigrade abundance. Mosses of the same species collected from a forest and from a clear-cut, respectively, did not show a general trend in the overall abundance of tardigrades, but the forest tended to contain more species. Five species of tardigrades (Murrayon dianae, Isohypsibius sattleri, Platicrista angustata, Diphascon belgicae and Diphascon pingue) never previously reported from Sweden were recorded.

  • 329.
    Jönsson, K. Ingemar
    Kristianstad University, Faculty of Natural Science, Research environment Man & Biosphere Health (MABH). Kristianstad University, Faculty of Natural Science, Avdelningen för miljö- och biovetenskap.
    Radiation tolerance in tardigrades: current knowledge and potential applications in medicine2019In: Cancers, ISSN 2072-6694, Vol. 11, no 9Article, review/survey (Refereed)
    Abstract [en]

    Tardigrades represent a phylum of very small aquatic animals in which many species have evolved adaptations to survive under extreme environmental conditions, such as desiccation and freezing. Studies on several species have documented that tardigrades also belong to the most radiation-tolerant animals on Earth. This paper gives an overview of our current knowledge on radiation tolerance of tardigrades, with respect to dose-responses, developmental stages, and different radiation sources. The molecular mechanisms behind radiation tolerance in tardigrades are still largely unknown, but omics studies suggest that both mechanisms related to the avoidance of DNA damage and mechanisms of DNA repair are involved. The potential of tardigrades to provide knowledge of importance for medical sciences has long been recognized, but it is not until recently that more apparent evidence of such potential has appeared. Recent studies show that stress-related tardigrade genes may be transfected to human cells and provide increased tolerance to osmotic stress and ionizing radiation. With the recent sequencing of the tardigrade genome, more studies applying tardigrade omics to relevant aspects of human medicine are expected. In particular, the cancer research field has potential to learn from studies on tardigrades about molecular mechanisms evolved to maintain genome integrity.

  • 330.
    Jönsson, K. Ingemar
    Kristianstad University, School of Education and Environment, Avdelningen för Naturvetenskap. Kristianstad University, Research environment Man & Biosphere Health (MABH).
    Radiation tolerance in tardigrades: evidence and implications2008In: Comparative Biochemistry and Physiology A, ISSN 1095-6433, E-ISSN 1531-4332, Vol. 151, no Suppl. 1, p. S33-Article in journal (Other academic)
    Abstract [en]

    Tardigrades belong to the most desiccation-tolerant animals on Earth, and are able to lose practically all water in their cells without dying. Recent investigations have also confirmed a seminal study from 1964 showing that tardigrades have an extraordinary tolerance also to ionizing radiation. The biochemical and physiological mechanisms behind these two tolerance phenomena, and the possible functional link between them, is currently not understood. However, the finding that desiccated and non-desiccated tardigrades show similar tolerances to ionizing radiation suggests that radiation tolerance in these animals is not a physical function of the dry state. Rather, both mechanisms preventing damage and mechanisms repairing damage to cell components are likely to be involved. The possible involvement of DNA repair mechanisms in tolerances of anhydrobiotic animals make them of special interest for understanding naturally evolved adaptations for coping with environmental agents inducing damage to DNA. I will summarize our current knowledge about radiation tolerance in tardigrades and other anhydrobiotic animals, discuss some of its implications for our understanding of desiccation tolerance, and also present some recent data on radiation tolerance in tardigrade embryos.

  • 331.
    Jönsson, K. Ingemar
    Lund University.
    Skendödens mästare1999In: Forskning och framsteg, ISSN 0015-7937, no 7, p. 38-41Article in journal (Other (popular science, discussion, etc.))
  • 332.
    Jönsson, K. Ingemar
    Lund University.
    The evolution of life histories in holo-anhydrobiotic animals: a first approach2005In: Integrative and Comparative Biology, ISSN 1540-7063, E-ISSN 1557-7023, Vol. 45, no 5, p. 764-770Article in journal (Refereed)
    Abstract [en]

    The life histories of holo-anhydrobiotic animals differ from those of all other organisms by a regular or irregular entrance into an ametabolic state induced by desiccation. Such ametabolic periods will arrest growth and reproduction completely and thus affect primary life history parameters dramatically. The selective forces and the genetic and physiological trade-offs acting on anhydrobiotic animals are to a large extent unknown. Assuming low growth rates and low juvenile to adult survival, general theoretical models on life history responses to stress predict that anhydrobiotic animals will be selected for a high degree of iteroparity, with low fecundity, large egg size, and low total reproductive investment. A high degree of variability in growth and reproduction should create a selective force in the same direction. Although basic empirical data on life history parameters are very scarce, available observations seem to be consistent with this prediction.

  • 333.
    Jönsson, K. Ingemar
    Kristianstad University, Faculty of Natural Science, Research environment Man & Biosphere Health (MABH). Kristianstad University, Faculty of Natural Science, Avdelningen för miljö- och biovetenskap.
    Transdisciplinär forskning visar vägen mot en hållbar ekologisk utveckling2018In: Man and Biosphere Health: en komplett akademisk miljö / [ed] Ann-Sofi Rehnstam-Holm, Kristianstad: Högskolan Kristianstad , 2018, p. 48-56Chapter in book (Other academic)
  • 334.
    Jönsson, K. Ingemar
    Kristianstad University, School of Education and Environment, Avdelningen för Naturvetenskap. Kristianstad University, Research environment Man & Biosphere Health (MABH).
    Tuffa djur prövas i rymden2007In: Populär astronomi, ISSN 1650-7177, Vol. 8, no 4, p. 10-Article in journal (Other (popular science, discussion, etc.))
  • 335.
    Jönsson, K. Ingemar
    et al.
    Kristianstad University, School of Education and Environment, Avdelningen för Naturvetenskap. Kristianstad University, Research environment Man & Biosphere Health (MABH).
    Czarnezki, J
    Eco-labeling policy in light of human behavioral ecology and evolutionary psychology2013Conference paper (Other academic)
    Abstract [en]

    Eco-labeling can foster environmentally friendly consumer behavior and, in the aggregate, influenceand reduce environmental harm. In light of consumer interest and perceived economics gains for producers and retailers for making and selling a value-added product, eco-labels have proliferated. Despite the increase in green labels, there are concerns about consumer confusion and best practices, and there is limited information on the best process in creating an eco-label, what types of eco-labels are effective in changing consumer behavior, and how they should be designed. Our approach to eco-labeling is that a successful labeling should be rooted in the basic evolutionary psychological mechanisms underlying human decisions and behavior. Thus, development of eco-labeling strategies may benefit from exploration of evolutionary theories on human behavior. Based on this premise we analyse various aspects of eco-labeling and discuss what eco-label strategies anddesigns are expected to be successful and which may not be so.

  • 336.
    Jönsson, K. Ingemar
    et al.
    Lund University.
    Harms-Ringdahl, Mats
    Stockholm University, Sweden.
    Torudd, Jesper
    Stockholm University.
    Radiation tolerance in the eutardigrade Richtersius coronifer2005In: International Journal of Radiation Biology, ISSN 0955-3002, E-ISSN 1362-3095, Vol. 81, no 9, p. 649-656Article in journal (Refereed)
    Abstract [en]

    PURPOSE: Tardigrades have a reputation of being extremely tolerant to extreme environmental conditions including tolerance to ionizing radiation while in a desiccated, anhydrobiotic state. However, the evidence for radio-tolerance in tardigrades is based on only one previous report, and there is an obvious need for complementary studies. In this paper we report an investigation on radio-tolerance in desiccated and hydrated specimens of the eutardigrade Richtersius coronifer.

    MATERIALS AND METHODS: Groups of 30 - 50 tardigrades were exposed to gamma-radiation at doses between 1.0 - 9.0 (anhydrobiotic animals) or 0.5 - 5.0 (hydrated animals) kGy and the animals were followed until all were dead. Radiation tolerance of both desiccated and hydrated tardigrades was studied.

    RESULTS: Both desiccated and hydrated animals irradiated with 0.5 and 1 kGy did not deviate in survival from the control groups. Animals from all exposed groups underwent their moulting and egg production cycle, but at decreasing frequency for doses above 1 kGy. No eggs laid by irradiated animals hatched, while eggs laid by controls did so.

    CONCLUSION: Our study suggests that radiation tolerance in tardigrades is not due to biochemical protectants connected with the desiccated state. Rather, cryptobiotic tardigrades may rely on efficient mechanisms of DNA repair, the nature of which is currently unknown.

  • 337.
    Jönsson, K. Ingemar
    et al.
    Kristianstad University, School of Education and Environment, Avdelningen för Naturvetenskap. Kristianstad University, Research environment Man & Biosphere Health (MABH).
    Herczeg, Gabor
    Finland.
    O´Hara, Robert
    Finland.
    Söderman, Fredrik
    Uppsala University.
    ter Schure, Arnout
    USA.
    Larsson, Per
    Lund University.
    Merilä, Juha
    Finland.
    Sexual patterns of prebreeding energy reserves in the common frog Rana temporaria along a latitudinal gradient2009In: Ecography, ISSN 0906-7590, E-ISSN 1600-0587, Vol. 32, no 5, p. 831-839Article in journal (Refereed)
    Abstract [en]

    The ability to store energy is an important life history trait for organisms facing long periods without energy income, and in particular for capital breeders such as temperate zone amphibians, which rely on stored energy during reproduction. However, large scale comparative studies of energy stores in populations with different environmental constraints on energy allocation are scarce. We investigated energy storage patterns in spring (after hibernation and before reproduction) in eight common frog (Rana temporaria) populations exposed to different environmental conditions along a 1600 km latitudinal gradient across Scandinavia (range of annual activity period 3-7 months). Analyses of lean body weight (eviscerated body mass), weight of fat bodies, liver weight, and liver fat content, showed that (i) post-hibernation/pre-breeding energy stores increased with increasing latitude in both sexes, (ii) males generally had larger energy reserves than females and (iii) the difference in energy stores between sexes decreased towards the north. Larger energy reserves towards the north can serve as a buffer against less predictable and/or less benign weather conditions during the short activity period, and may also represent a risk-averse tactic connected with a more pronounced iteroparous life history. In females, the continuous and overlapping vitellogenic activity in the north may also demand more reserves in early spring. The general sexual difference could be a consequence of the fact that, at the time of our sampling, females had already invested their energy into reproduction in the given year (i.e. their eggs were already ovulated), while the males' main reproductive activities (e.g. calling, mate searching, sexual competition) occurred later in the season.

  • 338.
    Jönsson, K. Ingemar
    et al.
    Kristianstad University, Faculty of Natural Science, Research environment Man & Biosphere Health (MABH). Kristianstad University, Faculty of Natural Science, Avdelningen för miljö- och biovetenskap.
    Holm, Ingvar
    Kristianstad University, Faculty of Natural Science, Research environment Man & Biosphere Health (MABH). Kristianstad University, Faculty of Natural Science, Avdelningen för miljö- och biovetenskap.
    Tassidis, Helena
    Kristianstad University, School of Education and Environment, Avdelningen för Naturvetenskap. Kristianstad University, Faculty of Natural Science, Research environment Man & Biosphere Health (MABH).
    Cell biology of the tardigrades: current knowledge and perspectives2019In: Evo-Devo: Non-model species in cell and developmental biology / [ed] Tworzydlo W., Bilinski S., Cham: Springer, 2019, p. 231-249Chapter in book (Other academic)
    Abstract [en]

    The invertebrate phylum Tardigrada has received much attention for containing species adapted to the most challenging environmental conditions where an ability to survive complete desiccation or freezing in a cryptobiotic state is necessary for persistence. Although research on tardigrades has a long history, the last decade has seen a dramatic increase in molecular biological (“omics”) studies, most of them with the aim to reveal the biochemical mechanisms behind desiccation tolerance of tardigrades. Several other aspects of tardigrade cell biology have been studied, and we review some of them, including karyology, embryology, the role of storage cells, and the question of whether tardigrades are eutelic animals. We also review some of the theories about how anhydrobiotic organisms are able to maintain cell integrity under dry conditions, and our current knowledge on the role of vitrification and DNA protection and repair. Many aspects of tardigrade stress tolerance have relevance for human medicine, and the first transfers of tardigrade stress genes to human cells have now appeared. We expect this field to develop rapidly in the coming years, as more genomic information becomes available. However, many basic cell biological aspects remain to be investigated, such as immunology, cell cycle kinetics, cell metabolism, and culturing of tardigrade cells. Such development will be necessary to allow tardigrades to move from a nonmodel organism position to a true model organism with interesting associations with the current models C. elegans and D. melanogaster.

  • 339.
    Jönsson, K. Ingemar
    et al.
    Kristianstad University, Research environment Man & Biosphere Health (MABH). Kristianstad University, School of Education and Environment, Avdelningen för Naturvetenskap.
    Hygum, Thomas L
    Danmark.
    Andersen, Kasper N
    Danmark.
    Clausen, Lykke K. B.
    Danmark.
    Møbjerg, Nadja
    Danmark.
    Tolerance to gamma radiation in the marine heterotardigrade, Echiniscoides sigismundi2016In: PLoS ONE, ISSN 1932-6203, E-ISSN 1932-6203, Vol. 11, no 12, article id e0168884Article in journal (Refereed)
    Abstract [en]

    Tardigrades belong to the most radiation tolerant animals on Earth, as documented by a number of studies using both low-LET and high-LET ionizing radiation. Previous studies have focused on semi-terrestrial species, which are also very tolerant to desiccation. The predominant view on the reason for the high radiation tolerance among these semi-terrestrial species is that it relies on molecular mechanisms that evolved as adaptations for surviving dehydration. In this study we report the first study on radiation tolerance in a marine tardigrade, Echiniscoides sigismundi. Adult specimens in the hydrated active state were exposed to doses of gamma radiation from 100 to 5000 Gy. The results showed little effect of radiation at 100 and 500 Gy but a clear decline in activity at 1000 Gy and higher. The highest dose survived was 4000 Gy, at which ca. 8% of the tardigrades were active 7 days after irradiation. LD50 in the first 7 days after irradiation was in the range of 1100±1600 Gy. Compared to previous studies on radiation tolerance in semi-terrestrial and limnic tardigrades, Echiniscoides sigismundi seems to have a lower tolerance. However, the species still fits into the category of tardigrades that have high tolerance to both desiccation and radiation, supporting the hypothesis that radiation tolerance is a by-product of adaptive mechanisms to survive desiccation. More studies on radiation tolerance in tardigrade species adapted to permanently wet conditions, both marine and freshwater, are needed to obtain a more comprehensive picture of the patterns of radiation tolerance.

  • 340.
    Jönsson, K. Ingemar
    et al.
    Lund University.
    Järemo, Johannes
    Lund University.
    A model on the evolution of cryptobiosis2003In: Annales Zoologici Fennici, ISSN 0003-455X, E-ISSN 1797-2450, Vol. 40, no 4, p. 331-340Article in journal (Refereed)
    Abstract [en]

    Cryptobiosis is an ametabolic state of life entered by some lower organisms (among metazoans mainly rotifers, tardigrades and nematodes) in response to adverse environmental conditions. Despite a long recognition of cryptobiotic organisms, the evolutionary origin and life history consequences of this biological phenomenon have remained unexplored. We present one of the first theoretical models on the evolution of cryptobiosis, using a hypothetical population of marine tardigrades that migrates between open sea and the tidal zone as the model framework. Our model analyses the conditions under which investments into anhydrobiotic (cryptobiosis induced by desiccation) functions will evolve, and which factors affect the optimal level Of Such investments. In particular, we evaluate how the probability of being exposed to adverse conditions (getting stranded) and the consequences for survival Of Such exposure (getting desiccated) affects the option for cryptobiosis to evolve. The optimal level of investment into anhydrobiotic traits increases with increasing probability of being stranded as well as with increasing negative survival effects of being stranded. However, our analysis shows that the effect on survival of being stranded is a more important parameter than the probability of stranding for the evolution of anhydrobiosis. The existing, although limited, evidence from empirical studies seems to support some of these predictions.

  • 341.
    Jönsson, K. Ingemar
    et al.
    Kristianstad University, Faculty of Natural Science, Research environment Man & Biosphere Health (MABH). Kristianstad University, Faculty of Natural Science, Avdelningen för miljö- och biovetenskap.
    Levin, Eliana B
    USA & Colombia.
    Wojcik, Andrzej
    Stockholm University.
    Haghdoost, Siamak
    Stockholm University & France.
    Harms-Ringdahl, Mats
    Stockholm University.
    Environmental adaptations: radiation tolerance2019In: Water bears: the biology of tardigrades / [ed] Ralph O Schill, Springer, 2019, p. 311-330Chapter in book (Other academic)
    Abstract [en]

    Several studies in different species have documented that tardigrades are among the most radiation-tolerant animals on Earth, surviving doses of ionizing radiation on the order of kGy. Both low-LET and high-LET radiation have been used with no apparent differences in the tolerance of the animals. Tolerance to ionizing radiation in tardigrades also seems to be independent of whether the animal has entered a dry anhydrobiotic state or is hydrated with normal activity. However, when exposed to UV radiation, desiccated tardigrades show a higher tolerance than hydrated animals. Recent studies in several species have shown that tardigrade embryos have considerably lower tolerance to ionizing radiation compared to adults, and embryos in the early stage of development are clearly more sensitive to radiation than those in the late developmental stage. The molecular mechanisms behind radiation tolerance in tardigrades are still largely unclear, but available evidence suggests that mechanisms related to both the avoidance of DNA damage and the repair of damage are involved.

  • 342.
    Jönsson, K. Ingemar
    et al.
    Kristianstad University, School of Education and Environment, Avdelningen för Naturvetenskap. Kristianstad University, Forskningsmiljön Man and Biosphere Health (MABH).
    Persson, Ola
    Kristianstad University, School of Education and Environment, Avdelningen för Naturvetenskap.
    Trehalose in three species of desiccation tolerant tardigrades2010In: Open Zoology Journal, ISSN 1874-3366, Vol. 3, p. 1-5Article in journal (Refereed)
    Abstract [en]

    We report a study on the presence of the disaccharide trehalose in three desiccation tolerant tardigrades. This sugar has long been suggested to play a protective role in desiccation tolerant animals. Trehalose was found in all species, with increased levels in dehydrated specimens of Macrobiotus islandicus, and possibly also in Macrobiotus krynauwi, both belonging to the family Macrobiotidae. In the third species, Milnesium tardigradum, very low amounts of trehalose were found, with no increase in the dehydrated state. This species has previously been reported to lack trehalose. Induction of trehalose has been reported only for species in the family Macrobiotidae, where also the highest levels have been found. Although the role of trehalose in the desiccation tolerance of tardigrades remains unclear, the diverging patterns in response to desiccation are interesting. Further studies of higher tardigrade taxa are needed in order to understand the evolutionary history of trehalose in these invertebrates.

  • 343.
    Jönsson, K. Ingemar
    et al.
    Kristianstad University, School of Education and Environment, Avdelningen för Naturvetenskap. Kristianstad University, Research environment Man & Biosphere Health (MABH).
    Rabbow, Elke
    Tyskland.
    Schill, Ralph O
    Tyskland.
    Harms-Ringdahl, Mats
    Stockholm University.
    Rettberg, Petra
    Tyskland.
    Tardigrades survive exposure to space in low earth orbit2008In: Current Biology, ISSN 0960-9822, E-ISSN 1879-0445, Vol. 18, no 17, p. R729-R731Article in journal (Refereed)
    Abstract [en]

    Vacuum (imposing extreme dehydration) and solar/galactic cosmic radiation prevent survival of most organisms in space . Only anhydrobiotic organisms, which have evolved adaptations to survive more or less complete desiccation, have a potential to survive space vacuum, and few organisms can stand the unfiltered solar radiation in space. Tardigrades, commonly known as water-bears, are among the most desiccation and radiation-tolerant animals and have been shown to survive extreme levels of ionizing radiation. Here, we show that tardigrades are also able to survive space vacuum without loss in survival, and that some specimens even recovered after combined exposure to space vacuum and solar radiation. These results add the first animal to the exclusive and short list of organisms that have survived such exposure.

  • 344.
    Jönsson, K. Ingemar
    et al.
    Lund University.
    Rebecchi, Lorena
    Italien.
    Experimentally induced anhydrobiosis in the tardigrade Richtersius coronifer: phenotypic factors affecting survival2002In: Journal of Experimental Zoology, ISSN 0022-104X, E-ISSN 1097-010X, Vol. 293, no 6, p. 578-584Article in journal (Refereed)
    Abstract [en]

    The ability of some animal taxa (e.g., nematodes, rotifers, and tardigrades) to enter an ametabolic (cryptobiotic) state is well known. Nevertheless, the phenotypic factors affecting successful anhydrobiosis have rarely been investigated. We report a laboratory study on the effects of body size, reproductive condition, and energetic condition on anhydrobiotic survival in a population of the eutardigrade Richtersius coronifer. Body size and energetic condition interacted in affecting the probability of survival, while reproductive condition had no effect. Large tardigrades had a lower probability of survival than medium-sized tardigrades and showed a positive response in survival to energetic condition. This suggests that energy constrained the possibility for large tardigrades toenter and to leave anhydrobiosis. As a possible alternative explanation for low survival in the largest specimens we discuss the expression of senescence. In line with the view that processes related to anhydrobiosis are connected with energetic costs we documented a decrease in the size of storage cells over a period of anhydrobiosis, showing for the first time that energy is consumed in the process of anhydrobiosis in tardigrades.

  • 345.
    Jönsson, K. Ingemar
    et al.
    Kristianstad University, Research environment Man & Biosphere Health (MABH). Kristianstad University, School of Education and Environment, Avdelningen för Naturvetenskap.
    Schill, Ralph O
    Tyskland.
    Rabbow, Elke
    Tyskland.
    Rettberg, Petra
    Tyskland.
    Harms-Ringdahl, Mats
    Stockholm University.
    The fate of the TARDIS offspring: no intergenerational effects of space exposure in Milnesium tardigradum2015Conference paper (Refereed)
    Abstract [en]

    In September 2007 tardigrades became the first animal in the history to survive the combined effect of exposure to space vacuum, cosmic radiation, and ultra-violet radiation in low Earth orbit. The main results from this experiment were reported in 2008, but some of the results have remained unpublished. Here we report that no delayed effects of the exposure to space could be detected in the descendants (up to F3 generation) of space exposed Milnesium tardigradum. This indicates that individual tardigrades that survived the damage induced by environmental agents in space, and were able to reproduce, did not transfer any delayed damage to later generations. Repair of environmentally induced damage may therefore follow a “make or break” rule, such that a damaged animal either fails to repair all damage and dies, or repairs damage successfully and leaves no mutations to descendants. We also provide previously unreported data on two tardigrade species, Echiniscus testudo and Ramazzottius oberhaeuseri, that showed high survival after exposure to space vacuum and cosmic radiation within the TARDIS experiment.

  • 346.
    Jönsson, K. Ingemar
    et al.
    Kristianstad University, Research environment Man & Biosphere Health (MABH). Kristianstad University, School of Education and Environment, Avdelningen för Naturvetenskap.
    Schill, Ralph
    Tyskland.
    Rabbow, Elke
    Tyskland.
    Rettberg, Petra
    Tyskland.
    Harms-Ringdahl, Mats
    Stockholm University.
    The fate of the TARDIS offspring: no intergenerational effects of space exposure2016In: Zoological Journal of the Linnean Society, ISSN 0024-4082, E-ISSN 1096-3642, Vol. 178, no 4, p. 924-930Article in journal (Refereed)
    Abstract [en]

    In September 2007 tardigrades became the first animal in history to survive the combined effect of exposure to space vacuum, cosmic radiation and ultraviolet radiation in low Earth orbit. The main results from this experiment were reported in 2008, but some of the results have remained unpublished. Here we report that descendant generations of space-exposed tardigrades of the species Milnesium tardigradum did not show reduced performance. This indicates that individual tardigrades that survived the exposure to environmental extremes in space, and were able to reproduce, did not transfer any damage to later generations. Repair of environmentally induced damage may therefore follow a ‘make or break’ rule, such that a damaged animal either fails to repair all damage and dies, or repairs damage successfully and leaves no mutations to descendants. We also report that two additional tardigrade species, Echiniscus testudo and Ramazzottius oberhaeuseri, showed high survival after exposure to space vacuum and cosmic radiation within the TARDIS experiment.

  • 347.
    Jönsson, K. Ingemar
    et al.
    Kristianstad University, Research environment Man & Biosphere Health (MABH). Kristianstad University, School of Education and Environment, Avdelningen för Naturvetenskap.
    Wojcik, Andrzej
    Stockholms universitet.
    Tolerance to X-rays and Heavy Ions (Fe, He) in the Tardigrade Richtersius coronifer and the Bdelloid Rotifer Mniobia russeola2017In: Astrobiology, ISSN 1531-1074, E-ISSN 1557-8070, Vol. 17, no 2, p. 163-167Article in journal (Refereed)
    Abstract [en]

    The aim of this study was to analyze tolerance to heavy ions in desiccated animals of the eutardigrade Richtersius coronifer and the bdelloid rotifer Mniobia russeola within the STARLIFE project. Both species were exposed to iron (Fe) and helium (He) ions at the Heavy Ion Medical Accelerator in Chiba (HIMAC) in Chiba, Japan, and to X-rays at the German Aerospace Center (DLR) in Cologne, Germany. Results show no effect of Fe and He on viability up to 7 days post-rehydration in both R. coronifer and M. russeola, while X-rays tended to reduce viability in R. coronifer at the highest doses. Mean egg production rate tended to decline with higher doses in R. coronifer for all radiation types, but the pattern was not statistically confirmed. In M. russeola, there was no such tendency for a dose response in egg production rate. These results confirm the previously reported high tolerance to high linear energy transfer (LET) radiation in tardigrades and show for the first time that bdelloid rotifers are also very tolerant to high-LET radiation. These animal phyla represent the most desiccation- and radiation-tolerant animals on Earth and provide excellent eukaryotic models for astrobiological research. 

  • 348.
    Kadin, Martina
    et al.
    Stockholm university.
    Elmberg, Johan
    Kristianstad University, School of Education and Environment, Avdelningen för Naturvetenskap.
    Patterns and trade-offs among multiple ecosystem services from marine bird species2015In: 2nd World Seabird Conference: seabirds: Global ocean sentinels, 2015Conference paper (Refereed)
    Abstract [en]

    Ecosystem services (ES) are increasingly incorporated into management of marine and coastal resources. Local investigations of generation and utilization of ES are desirable but may be costly, highlighting a need to develop general tools helping to predict the ES associated with a particular resource or site. Functional guilds or trait-based approaches have been suggested as one way to predict the capacity to deliver desired ES. We assess the ES provided by six species, from pairs of two ecologically similar species in each of the families Anatidae, Alcidae and Phalacrocoracidae, and selected to show the applicability and limitations of such approaches applied to marine birds. The set of ES, interactions between them and differences between populations, are examined for each species. This helps to reveal when the characteristics of ES can be predicted based on knowledge from elsewhere or similar species, or when the local context needs to be analyzed. Our findings suggest that services more closely linked to ecological processes, which include many regulating and supporting services, are often similar within functional guilds. We also find that including breeding habits when defining guilds increases the general applicability of the concept. Cultural services, and services linked to local and scientific knowledge, depend to large extents on local context, on the other hand. This complicates the process of generalizing results regarding interactions and trade-offs between ES for species or populations that make significant contributions to substantially different kinds of services.

  • 349.
    Kaminski, Richard M.
    et al.
    Mississippi State University.
    Elmberg, Johan
    Kristianstad University, School of Education and Environment, Avdelningen för Naturvetenskap. Kristianstad University, Research environment Man and Biosphere Health (MABH).
    An introduction to habitat use and selection by waterfowl in the northern hemisphere2014In: Wildfowl, ISSN 0954-6324, E-ISSN 2052-6458, no Special Issue 4, p. 9-16Article in journal (Refereed)
    Abstract [en]

    This introductory article aims to provide a theoretical framework to the topics of habitat use and selection by waterfowl (i.e. family Anatidae) in the northern hemisphere during the four stages of their annual cycle: autumn migration and winter, spring migration and pre-breeding, nesting and brood rearing, and postbreeding and moulting. Papers addressing each of these seasonal sectors of the annual cycle, which follow this introduction, were presented at the 6th North American Duck Symposium, “Ecology and Conservation of North American Waterfowl” in Memphis, Tennessee in January 2013. Here, we consider the theory and selected empirical evidence relevant to waterfowl habitat and resource use and selection that may affect individual survival and fitness of waterfowl in Nearctic and Palearctic ecozones. Additionally, where possible, a comparative taxonomic approach is attempted in the following papers to identify and generalise patterns in habitat and resource use and selection across waterfowl taxa that may influence biological outcomes for individuals, populations and species through space and time. Each of the subsequent papers use accumulated science-based information to recommend future opportunities and strategies for research and for habitat and population conservation. Collectively, our goals in synthesising information on waterfowl are to help sustain harvestable populations of waterfowl and to protect rare species amid worldwide changes in climate, landscape, economics, socio-politics and growth of human populations.

  • 350.
    Karlson, Bengt
    et al.
    SMHI.
    Rehnstam-Holm, Ann-Sofi
    Kristianstad University, School of Education and Environment, Avdelningen för Naturvetenskap. Kristianstad University, Forskningsmiljön Man and Biosphere Health (MABH).
    Algal toxins (DSP/PSP Mussel Infection Events)2002In: Swedish national report on eutrophication status in the Kattegatt and the Skagerrak: OSPAR assessment 2002 / [ed] Bertil Håkansson, Norrköping: SMHI , 2002, p. 50-52Chapter in book (Other academic)
    Abstract [en]

    The blue mussels (Mytilus edulis) along the Swedish west coast have contained DSP-toxins above the limit for consumption during part of the year every year since the monitoring programme started in 1988. Some areas that previously have been believed to be toxin free have experienced toxic events the last few years. PSP-toxins occur only rarely and usually below the limit for ban of consumption. However, e.g. in 2002, concentrations were higher than the limit for a short period in one fjord.

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