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Tůmová M, Jílková V, Macek P, Devetter M. Tardigrade distribution in soils of high Arctic habitats. Ecol Evol 2024; 14:e11386. [PMID: 38962018 PMCID: PMC11222015 DOI: 10.1002/ece3.11386] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/24/2023] [Revised: 04/19/2024] [Accepted: 04/24/2024] [Indexed: 07/05/2024] Open
Abstract
Tardigrades are omnipresent microfauna with scarce record on their ecology in soils. Here, we investigated soil inhabiting tardigrade communities in five contrasting polar habitats, evaluating their abundance, diversity, species richness, and species composition. Moreover, we measured selected soil physico-chemical properties to find the drivers of tardigrade distribution among these habitats. In spite of reported tardigrade viability in extreme conditions, glacier forelands represented a habitat almost devoid of tardigrades. Even dry and wet tundra with soil developing for over more than 10 000 years held low abundances compared to usual numbers of tardigrades in temperate habitats. Polar habitats also differ in species composition, with Diaforobiotus islandicus being typical species for dry and Hypsibius exemplaris for wet tundra. Overall, tardigrade abundance was affected by the content of nutrients as well as physical properties of soil, i.e. content of total nitrogen (TN), total organic carbon (TOC), stoniness, soil texture and the water holding capacity (WHC). While diversity and species composition were significantly related to soil physical properties such as the bulk density (BD), soil texture, stoniness, and WHC. Physical structure of environment was, therefore, an important predictor of tardigrade distribution in polar habitats. Since many studies failed to identify significant determinants of tardigrade distribution, we encourage scientists to include physical properties of tardigrade habitats as explanatory variables in their studies.
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Affiliation(s)
- Michala Tůmová
- Faculty of ScienceUniversity of South BohemiaČeské BudějoviceCzech Republic
- Institute of Soil Biology and BiogeochemistryBiology Centre, Czech Academy of SciencesČeské BudějoviceCzech Republic
| | - Veronika Jílková
- Institute of Soil Biology and BiogeochemistryBiology Centre, Czech Academy of SciencesČeské BudějoviceCzech Republic
| | - Petr Macek
- Institute of HydrobiologyBiology Centre, Czech Academy of SciencesČeské BudějoviceCzech Republic
- Institute of Agricultural and Environmental SciencesEstonian University of Life SciencesTartuEstonia
| | - Miloslav Devetter
- Institute of Soil Biology and BiogeochemistryBiology Centre, Czech Academy of SciencesČeské BudějoviceCzech Republic
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Jackson AC, Jorna J, Chaston JM, Adams BJ. Glacial Legacies: Microbial Communities of Antarctic Refugia. BIOLOGY 2022; 11:biology11101440. [PMID: 36290344 PMCID: PMC9598129 DOI: 10.3390/biology11101440] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/31/2022] [Revised: 09/26/2022] [Accepted: 09/30/2022] [Indexed: 11/06/2022]
Abstract
In the cold deserts of the McMurdo Dry Valleys (MDV) the suitability of soil for microbial life is determined by both contemporary processes and legacy effects. Climatic changes and accompanying glacial activity have caused local extinctions and lasting geochemical changes to parts of these soil ecosystems over several million years, while areas of refugia may have escaped these disturbances and existed under relatively stable conditions. This study describes the impact of historical glacial and lacustrine disturbance events on microbial communities across the MDV to investigate how this divergent disturbance history influenced the structuring of microbial communities across this otherwise very stable ecosystem. Soil bacterial communities from 17 sites representing either putative refugia or sites disturbed during the Last Glacial Maximum (LGM) (22-17 kya) were characterized using 16 S metabarcoding. Regardless of geographic distance, several putative refugia sites at elevations above 600 m displayed highly similar microbial communities. At a regional scale, community composition was found to be influenced by elevation and geographic proximity more so than soil geochemical properties. These results suggest that despite the extreme conditions, diverse microbial communities exist in these putative refugia that have presumably remained undisturbed at least through the LGM. We suggest that similarities in microbial communities can be interpreted as evidence for historical climate legacies on an ecosystem-wide scale.
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Affiliation(s)
- Abigail C. Jackson
- Department of Biology, Brigham Young University, Provo, UT 84602, USA
- Correspondence: (A.C.J.); (J.J.)
| | - Jesse Jorna
- Department of Biology, Brigham Young University, Provo, UT 84602, USA
- Correspondence: (A.C.J.); (J.J.)
| | - John M. Chaston
- Department of Plant and Wildlife Sciences, Brigham Young University, Provo, UT 84602, USA
| | - Byron J. Adams
- Department of Biology, Brigham Young University, Provo, UT 84602, USA
- Monte L. Bean Museum, Brigham Young University, Provo, UT 84602, USA
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Kihm JH, Kim S, McInnes SJ, Zawierucha K, Rho HS, Kang P, Park TYS. Integrative description of a new Dactylobiotus (Eutardigrada: Parachela) from Antarctica that reveals an intraspecific variation in tardigrade egg morphology. Sci Rep 2020; 10:9122. [PMID: 32499591 PMCID: PMC7272612 DOI: 10.1038/s41598-020-65573-1] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/10/2019] [Accepted: 05/06/2020] [Indexed: 02/01/2023] Open
Abstract
Tardigrades constitute one of the most important group in the challenging Antarctic terrestrial ecosystem. Living in various habitats, tardigrades play major roles as consumers and decomposers in the trophic networks of Antarctic terrestrial and freshwater environments; yet we still know little about their biodiversity. The Eutardigrada is a species rich class, for which the eggshell morphology is one of the key morphological characters. Tardigrade egg morphology shows a diverse appearance, and it is known that, despite rare, intraspecific variation is caused by seasonality, epigenetics, and external environmental conditions. Here we report Dactylobiotus ovimutans sp. nov. from King George Island, Antarctica. Interestingly, we observed a range of eggshell morphologies from the new species, although the population was cultured under controlled laboratory condition. Thus, seasonality, environmental conditions, and food source are eliminated, leaving an epigenetic factor as a main cause for variability in this case.
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Affiliation(s)
- Ji-Hoon Kihm
- Division of Polar Earth-System Sciences, Korea Polar Research Institute, 26 Songdomirae-ro, Yeonsu-gu, 21990, Incheon, Korea
- Polar Science, University of Science & Technology, 217 Gajeong-ro, Yuseong-gu, 34113, Daejeon, Korea
| | - Sanghee Kim
- Division of Polar Life Sciences, Korea Polar Research Institute, 26 Songdomirae-ro, Yeonsu-gu, 21990, Incheon, Korea
| | - Sandra J McInnes
- British Antarctic Survey, Natural Environment Research Council, High Cross, Madingley Road, Cambridge, CB3 0ET, UK
| | - Krzysztof Zawierucha
- Department of Animal Taxonomy and Ecology, Faculty of Biology, Adam Mickiewicz University, Poznań, Uniwersytetu Poznańskiego 6, 61-614, Poznań, Poland
| | - Hyun Soo Rho
- East Sea Environment Research Center, East Sea Research Institute, Korea Institute of Ocean Science & Technology, 48 Haeyanggwahak-gil, Uljin, 36315, Gyeongsangbuk-do, Korea
| | - Pilmo Kang
- Division of Polar Earth-System Sciences, Korea Polar Research Institute, 26 Songdomirae-ro, Yeonsu-gu, 21990, Incheon, Korea
| | - Tae-Yoon S Park
- Division of Polar Earth-System Sciences, Korea Polar Research Institute, 26 Songdomirae-ro, Yeonsu-gu, 21990, Incheon, Korea.
- Polar Science, University of Science & Technology, 217 Gajeong-ro, Yuseong-gu, 34113, Daejeon, Korea.
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Devetter M, Háněl L, Řeháková K, Doležal J. Diversity and feeding strategies of soil microfauna along elevation gradients in Himalayan cold deserts. PLoS One 2017; 12:e0187646. [PMID: 29131839 PMCID: PMC5683576 DOI: 10.1371/journal.pone.0187646] [Citation(s) in RCA: 24] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/05/2017] [Accepted: 10/23/2017] [Indexed: 11/26/2022] Open
Abstract
High-elevation cold deserts in Tibet and Himalaya are one of the most extreme environments. One consequence is that the diversity of macrofauna in this environment is often limited, and soil microorganisms have a more influential role in governing key surface and subsurface bioprocesses. High-elevation soil microfauna represent important components of cold ecosystems and dominant consumers of microbial communities. Still little is known about their diversity and distribution on the edge of their reproductive and metabolic abilities. In this study, we disentangle the impact of elevation and soil chemistry on diversity and distribution of rotifers, nematodes and tardigrades and their most frequent feeding strategies (microbial filter-feeders, bacterivores, fungivores, root-fungal feeders, omnivores) along two contrasting altitudinal gradients in Indian NW Himalaya (Zanskar transect from 3805 to 4714 m a.s.l.) and southwestern Tibet (Tso Moriri transect from 4477 to 6176 m a.s.l.), using a combination of multivariate analysis, variation partitioning and generalized additive models. Zanskar transect had higher precipitation, soil moisture, organic matter and available nutrients than dry Tso Moriri transect. In total, 40 species of nematodes, 19 rotifers and 1 tardigrade were discovered. Species richness and total abundance of rotifers and nematodes showed mid-elevation peaks in both investigated transects. The optimum for rotifers was found at higher elevation than for nematodes. Diversity and distribution of soil microfauna was best explained by soil nitrogen, phosphorus and organic matter. More fertile soils hosted more diverse and abundant faunal communities. In Tso Moriri, bacterivores represented 60% of all nematodes, fungivores 35%, root-fungal feeders 1% and omnivores 3%. For Zanskar the respective proportions were 21%, 13%, 56% and 9%. Elevational optima of different feeding strategies occurred in Zanskar in one elevation zone (4400–4500 m), while in Tso Moriri each feeding strategy had their unique optima with fungivores at 5300 m (steppes), bacterivores at 5500 m (alpine grassland), filter-feeders at 5600 m and predators and omnivores above 5700 m (subnival zone). Our results shed light on the diversity of microfauna in the high-elevation cold deserts and disentangle the role of different ecological filters in structuring microfaunal communities in the rapidly-warming Himalayas.
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Affiliation(s)
- Miloslav Devetter
- Institute of Soil Biology, Biology Centre of The Czech Academy of Sciences, České Budějovice, Czech Republic
- Centre for Polar Ecology, Faculty of Science, University of South Bohemia, České Budějovice, Czech Republic
- * E-mail:
| | - Ladislav Háněl
- Institute of Soil Biology, Biology Centre of The Czech Academy of Sciences, České Budějovice, Czech Republic
| | - Klára Řeháková
- Section of Plant Ecology, Institute of Botany of The Czech Academy of Sciences, Třeboň, Czech Republic
- Institute of Hydrobiology, Biology Centre of The Czech Academy of Sciences, České Budějovice, Czech Republic
| | - Jiří Doležal
- Section of Plant Ecology, Institute of Botany of The Czech Academy of Sciences, Třeboň, Czech Republic
- Department of Botany, Faculty of Science, University of South Bohemia, České Budějovice, Czech Republic
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Czechowski P, White D, Clarke L, McKay A, Cooper A, Stevens MI. Age-related environmental gradients influence invertebrate distribution in the Prince Charles Mountains, East Antarctica. ROYAL SOCIETY OPEN SCIENCE 2016; 3:160296. [PMID: 28083092 PMCID: PMC5210674 DOI: 10.1098/rsos.160296] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/30/2016] [Accepted: 11/17/2016] [Indexed: 05/22/2023]
Abstract
The potential impact of environmental change on terrestrial Antarctic ecosystems can be explored by inspecting biodiversity patterns across large-scale gradients. Unfortunately, morphology-based surveys of Antarctic invertebrates are time-consuming and limited by the cryptic nature of many taxa. We used biodiversity information derived from high-throughput sequencing (HTS) to elucidate the relationship between soil properties and invertebrate biodiversity in the Prince Charles Mountains, East Antarctica. Across 136 analysed soil samples collected from Mount Menzies, Mawson Escarpment and Lake Terrasovoje, we found invertebrate distribution in the Prince Charles Mountains significantly influenced by soil salinity and/or sulfur content. Phyla Tardigrada and Arachnida occurred predominantly in low-salinity substrates with abundant nutrients, whereas Bdelloidea (Rotifera) and Chromadorea (Nematoda) were more common in highly saline substrates. A significant correlation between invertebrate occurrence, soil salinity and time since deglaciation indicates that terrain age indirectly influences Antarctic terrestrial biodiversity, with more recently deglaciated areas supporting greater diversity. Our study demonstrates the value of HTS metabarcoding to investigate environmental constraints on inconspicuous soil biodiversity across large spatial scales.
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Affiliation(s)
- Paul Czechowski
- Australian Centre for Ancient DNA, University of Adelaide, Adelaide, South Australia 5005, Australia
- Antarctic Biological Research Initiative, Bolivar, South Australia 5110, Australia
- Author for correspondence: Paul Czechowski e-mail:
| | - Duanne White
- Institute for Applied Ecology, University of Canberra, Canberra, Australian Capital Territory 2601, Australia
| | - Laurence Clarke
- Australian Centre for Ancient DNA, University of Adelaide, Adelaide, South Australia 5005, Australia
- Australian Antarctic Division, Kingston, Tasmania 7050, Australia
- Antarctic Climate and Ecosystems Cooperative Research Centre, University of Tasmania, Hobart, Tasmania 7001, Australia
| | - Alan McKay
- Plant and Soil Health, South Australian Research and Development Institute, Waite Campus, Urrbrae, South Australia 5064, Australia
| | - Alan Cooper
- Australian Centre for Ancient DNA, University of Adelaide, Adelaide, South Australia 5005, Australia
| | - Mark I. Stevens
- South Australian Museum, Science Centre, Adelaide, South Australia 5000, Australia
- School of Pharmacy and Medical Sciences, University of South Australia, Adelaide, South Australia 5001, Australia
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Lyons WB, Deuerling K, Welch KA, Welch SA, Michalski G, Walters WW, Nielsen U, Wall DH, Hogg I, Adams BJ. The Soil Geochemistry in the Beardmore Glacier Region, Antarctica: Implications for Terrestrial Ecosystem History. Sci Rep 2016; 6:26189. [PMID: 27189430 PMCID: PMC4870638 DOI: 10.1038/srep26189] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/07/2016] [Accepted: 04/22/2016] [Indexed: 12/04/2022] Open
Abstract
Although most models suggest continental Antarctica was covered by ice during the Last Glacial Maximum (LGM) it has been speculated that endemic species of soil invertebrates could have survived the Pleistocene at high elevation habitats protruding above the ice sheets. We analyzed a series of soil samples from different elevations at three locations along the Beardmore Glacier in the Transantarctic Mountains (in order of increasing elevation): Ebony Ridge (ER), Cloudmaker (CM), and Meyer Desert (MD). Geochemical analyses show the MD soils, which were exposed during the LGM, were the least weathered compared to lower elevations, and also had the highest total dissolved solids (TDS). MD soils are dominated by nitrate salts (NO3/Cl ratios >10) that can be observed in SEM images. High δ17O and δ18O values of the nitrate indicate that its source is solely of atmospheric origin. It is suggested that nitrate concentrations in the soil may be utilized to determine a relative “wetting age” to better assess invertebrate habitat suitability. The highest elevation sites at MD have been exposed and accumulating salts for the longest times, and because of the salt accumulations, they were not suitable as invertebrate refugia during the LGM.
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Affiliation(s)
- W B Lyons
- The Ohio State University, Columbus, OH 43210 USA
| | - K Deuerling
- The Ohio State University, Columbus, OH 43210 USA
| | - K A Welch
- The Ohio State University, Columbus, OH 43210 USA
| | - S A Welch
- The Ohio State University, Columbus, OH 43210 USA
| | | | | | - U Nielsen
- Hawkesbury Institute for the Environment, Western Sydney University, Penrith NSW 2751, Australia
| | - D H Wall
- Colorado State University, Ft Collins, CO USA
| | - I Hogg
- University of Waikato, Hamilton, New Zealand
| | - B J Adams
- Brigham Young University, Provo, UT USA
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The influence of a seabird colony on abundance and species composition of water bears (Tardigrada) in Hornsund (Spitsbergen, Arctic). Polar Biol 2015. [DOI: 10.1007/s00300-015-1827-4] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/22/2022]
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8
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Life history of the Antarctic tardigrade, Acutuncus antarcticus, under a constant laboratory environment. Polar Biol 2015. [DOI: 10.1007/s00300-015-1718-8] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/23/2022]
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Velasco-Castrillón A, McInnes SJ, Schultz MB, Arróniz-Crespo M, D'Haese CA, Gibson JAE, Adams BJ, Page TJ, Austin AD, Cooper SJB, Stevens MI. Mitochondrial DNA analyses reveal widespread tardigrade diversity in Antarctica. INVERTEBR SYST 2015. [DOI: 10.1071/is14019] [Citation(s) in RCA: 23] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/23/2022]
Abstract
Antarctica contains some of the most challenging environmental conditions on the planet due to freezing temperatures, prolonged winters and lack of liquid water. Whereas 99.7% of Antarctica is permanently covered by ice and snow, some coastal areas and mountain ridges have remained ice-free and are able to sustain populations of microinvertebrates. Tardigrades are one of the more dominant groups of microfauna in soil and limno-terrestrial habitats, but little is known of their diversity and distribution across Antarctica. Here, we examine tardigrades sampled from across an extensive region of continental Antarctica, and analyse and compare their partial mitochondrial cytochrome c oxidase subunit 1 (COI) gene sequences with those from the Antarctic Peninsula, maritime and sub-Antarctica, Tierra del Fuego and other worldwide locations in order to recognise operational taxonomic units (OTUs). From 439 new tardigrade COI sequences, we identified 98 unique haplotypes (85 from Antarctica) belonging to Acutuncus, Diphascon, Echiniscus, Macrobiotus, Milnesium and unidentified Parachela. Operational taxonomic units were delimited by Poisson tree processes and general mixed Yule coalescent methods, resulting in 58 and 55 putative species, respectively. Most tardigrades appear to be locally endemic (i.e. restricted to a single geographic region), but some (e.g. Acutuncus antarcticus (Richters, 1904)) are widespread across continental Antarctica. Our molecular results reveal: (i) greater diversity than has previously been appreciated with distinct OTUs that potentially represent undescribed species, and (ii) a lack of connectivity between most OTUs from continental Antarctica and those from other Antarctic geographical zones.
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Stevens MI, D’Haese CA. Islands in ice: isolated populations ofCryptopygus sverdrupi(Collembola) among nunataks in the Sør Rondane Mountains, Dronning Maud Land, Antarctica. ACTA ACUST UNITED AC 2014. [DOI: 10.1080/14888386.2014.928791] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/25/2022]
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12
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Velasco-Castrillón A, Page TJ, Gibson JAE, Stevens MI. Surprisingly high levels of biodiversity and endemism amongst Antarctic rotifers uncovered with mitochondrial DNA. ACTA ACUST UNITED AC 2014. [DOI: 10.1080/14888386.2014.930717] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/25/2022]
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13
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Distribution and diversity of soil microfauna from East Antarctica: assessing the link between biotic and abiotic factors. PLoS One 2014; 9:e87529. [PMID: 24498126 PMCID: PMC3909186 DOI: 10.1371/journal.pone.0087529] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/10/2013] [Accepted: 12/27/2013] [Indexed: 11/19/2022] Open
Abstract
Terrestrial life in Antarctica has been described as some of the simplest on the planet, and mainly confined to soil microfaunal communities. Studies have suggested that the lack of diversity is due to extreme environmental conditions and thought to be driven by abiotic factors. In this study we investigated soil microfauna composition, abundance, and distribution in East Antarctica, and assessed correlations with soil geochemistry and environmental variables. We examined 109 soil samples from a wide range of ice-free habitats, spanning 2000 km from Framnes Mountains to Bailey Peninsula. Microfauna across all samples were patchily distributed, from complete absence of invertebrates to over 1600 specimens/gram of dry weight of soil (gdw), with highest microfauna abundance observed in samples with visible vegetation. Bdelloid rotifers were on average the most widespread found in 87% of sampled sites and the most abundant (44 specimens/gdw). Tardigrades occurred in 57% of the sampled sites with an abundance of 12 specimens/gdw. Nematodes occurred in 71% of samples with a total abundance of 3 specimens/gdw. Ciliates and mites were rarely found in soil samples, with an average abundance of 1.3 and 0.04 specimens/gdw, respectively. We found that microfaunal composition and abundance were mostly correlated with the soil geochemical parameters; phosphorus, NO3− and salinity, and likely to be the result of soil properties and historic landscape formation and alteration, rather than the geographic region they were sampled from. Studies focusing on Antarctic biodiversity must take into account soil geochemical and environmental factors that influence population and species heterogeneity.
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Wilson CG, Sherman PW. Spatial and temporal escape from fungal parasitism in natural communities of anciently asexual bdelloid rotifers. Proc Biol Sci 2013; 280:20131255. [PMID: 23825214 DOI: 10.1098/rspb.2013.1255] [Citation(s) in RCA: 22] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022] Open
Abstract
Sexual reproduction is costly, but it is nearly ubiquitous among plants and animals, whereas obligately asexual taxa are rare and almost always short-lived. The Red Queen hypothesis proposes that sex overcomes its costs by enabling organisms to keep pace with coevolving parasites and pathogens. If so, the few cases of stable long-term asexuality ought to be found in groups whose coevolutionary interactions with parasites are unusually weak. In theory, antagonistic coevolution will be attenuated if hosts disperse among patches within a metapopulation separately from parasites and more rapidly. We examined whether these conditions are met in natural communities of bdelloid rotifers, one of the longest-lived asexual lineages. At any life stage, these microscopic invertebrates can tolerate the complete desiccation of their ephemeral freshwater habitats, surviving as dormant propagules that are readily carried by the wind. In our field experiments, desiccation and wind transport enabled bdelloids to disperse independently of multiple fungal parasites, in both time and space. Surveys of bdelloid communities in unmanipulated moss patches confirmed that fungal parasitism was negatively correlated with extended drought and increasing height (exposure to wind). Bdelloid ecology therefore matches a key condition of models in which asexuals persist through spatio-temporal decoupling from coevolving enemies.
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Affiliation(s)
- Christopher G Wilson
- Division of Ecology and Evolution, Imperial College London, Silwood Park Campus, Buckhurst Road, Ascot, Berkshire SL5 7PY, UK.
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Smykla J, Iakovenko N, Devetter M, Kaczmarek Ł. Diversity and distribution of tardigrades in soils of Edmonson Point (Northern Victoria Land, continental Antarctica). ACTA ACUST UNITED AC 2012. [DOI: 10.5817/cpr2012-2-6] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
Abstract
This work contributes to the knowledge on distribution, diversity and ecology of the Antarctic soil biota. Different soil habitats from several ice-free coastal sites were sampled along the Victoria Land across 7° of latitude from 71° to 78°S during five austral summer seasons between 2003/04 and 2011/12. In this paper we report preliminary data on soil tardigrades (water bears) from Edmondson Point, Northern Victoria Land. Tardigrades were found to be present in 23 of the 41 examined soil samples (56%). Their presence was associated exclusively with soil samples collected from bryophytes communities and under cyanobacterial mats, whereas they were completely absent in fellfield and ornithogenic soils. Tardigrades were least numerous among all soil micrometazoans, their abundance in the positive samples was very variable and ranged from 3 to 1824 individuals per 100 g of soil DW. High water content seemed to be the major factor determining occurrence of tardigrades in the soils investigated. On the other hand low water content and toxic compounds from penguin guano seemed to act as a strong constraint on their existence in the Antarctic soils. Taxonomic evaluation of the extracted tardigrades revealed presence of only two species belonging to class Eutardigrada: Acutuncus antarcticus (Richters, 1904) and Milnesium antarcticum Tumanov, 2006. While A. antarcticus has already been reported previously as the most widespread and abundant tardigrade across the Victoria Land, the information on M. antarcticum is novel, both for Victoria Land and the continental Antarctica.
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LEE JENNIFERE, LE ROUX PETERC, MEIKLEJOHN KIAN, CHOWN STEVENL. Species distribution modelling in low-interaction environments: Insights from a terrestrial Antarctic system. AUSTRAL ECOL 2012. [DOI: 10.1111/j.1442-9993.2012.02401.x] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
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17
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Nielsen UN, Wall DH, Adams BJ, Virginia RA. Antarctic nematode communities: observed and predicted responses to climate change. Polar Biol 2011. [DOI: 10.1007/s00300-011-1021-2] [Citation(s) in RCA: 39] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
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