Swedish Museum of Natural History
Swedish Museum of Natural History
News Article | March 16, 2017
A group of researchers at the Swedish Museum of Natural History have discovered a fossil of a plant, which is estimated to be 1.6 billion years old. It is believed that the fossil belong to a red algae from that period. If what the scientists conclude is true, then this is the oldest fossil of a plant ever discovered. Previous findings have revealed plant fossils from 1.2 billion years ago and scientists had concluded that it was around that time period when complex plant like organisms started to evolve. However, this recent discovery disproves the previous assumption and suggests that plants could have developed nearly 400 million years earlier than believed previously. Scientists posit that the fossils discovered in India belongs to red algae as they were able to espy distinct cellular structure, along with bundles of packed and splaying filaments which are found in the particular organism. "You cannot be a hundred per cent sure about material this ancient, as there is no DNA remaining, but the characters agree quite well with the morphology and structure of red algae," clarifies Stefan Bengtson who is the Professor emeritus of Palaeozoology at the Swedish Museum of Natural History. The fossils which were found in Chitrakoot region of India were originally believed to have belonged to the Cambrian Period, which was around 540 million years ago. This is the time period when multicellular eukaryotic organisms were common. However, through a process known as radiometric dating it was revealed that the sample was much older than anticipated and it actually belonged to the "Boring Billion" time period, which extends from 800 million to 1.8 billion years ago. This process was challenging as there was a lack of fossils from this time period. However, Bengtson concluded that photosynthetic eukaryotic life had evolved much earlier than what the scientific community previously believed. Palaeontologists from around the world appreciated these findings as they shed new light in the study of evolution of life forms. "When we start using some of these techniques to look at slightly older or at least equivalent aged fossils, we might start to see that these things are more common than we previously thought," commented Glenn Brock, palaeobologist at the Macquarie University, on the fidnings of the study. He also said that the advancement in technology has opened up new avenues to study fossils and make better assessment about the period it belonged to. He revealed that recent studies performed using biochemical techniques had even suggested that plant life may have been present as far back as 2.6 billion years ago. The study on the fossil found in India has been published in PLOS Biology. © 2017 Tech Times, All rights reserved. Do not reproduce without permission.
News Article | April 26, 2017
Researchers from the Swedish Museum of Natural History uncovered the fossils of what appears to be a 2.4-billion-year-old fungus preserved inside ancient basaltic rocks in South Africa. The fossil samples were recovered from the ancient basalt of the Ongeluk Formation, in the vicinity of the Northern Cape Province. These rocks were once found beneath the sea floor, having been formed by lava flowing under the sea bed. The scientists who made this surprising archaeological discovery suggest these fossils could in fact be the world's oldest fungus — preceding the next-oldest fungus specimen by 2 billion years. The samples drilled out of the ancient rocks resemble living fungi and, despite being much older, are almost identical with fossils unearthed from similar land environments. The fossils are made up of mycelia filaments no wider than hundredths of a millimeter (1 mm is equivalent to 0.03 inches), that "branch and anastomose, touch and entangle each other," document the researchers. The team, led by Professor Stefan Bengtson, detailed their discovery in the journal Nature Ecology & Evolution. The researchers believe these fungi may have colonized cavities of volcanic rock deep beneath the sea floor. They suggest that fungi arose not on land but in the deep sea — which is where science should have looked for the oldest fossil fungi all along, instead of on land or in shallow seas. "The deep biosphere (where the fossils were found) represents a significant portion of the Earth, but we know very little about its biology and even less about its evolutionary history," said Bengtson in a statement for BBC News. According to his study, the Ongeluk fossils "are indistinguishable from mycelial fossils found in similar deep-biosphere habitats in the Phanerozoic," which the researchers show were identified as fungi based on "chemical and morphological similarities to living fungi." Although the habitat from where the specimens were retrieved "is at least 400 million years old," the Ongeluk discovery "suggests that life has inhabited submarine volcanics for more than 2.4 billion years." Bengtson's team reports the newly discovered fossils are "two to three times older than current age estimates" of the fungus fossil record. "Unless they represent an unknown branch of fungus-like organisms, the fossils imply that the fungal clade is considerably older than previously thought, and that fungal origin and early evolution may lie in the oceanic deep biosphere rather than on land," write the authors in their paper's abstract. The importance of this remarkable find lies in its potential to substantially change the generally accepted timeline of early evolution on our planet. If confirmed, the discovery could alter "our sense of the timetable of evolutionary history," said Andrew H. Knoll, natural history professor at Harvard University. Nevertheless, Knoll is skeptical about the timeframe proposed by the Swedish researchers. According to Seeker, since fungi belong to the eukaryote family — a group of early organisms that have evolved a complex cell structure for which they require oxygen — fungus-like eukaryotes living 2.4 billion years ago "would have been using oxygen at nearly the same time scientists think oxygen first appeared in notable amounts on the planet." Knoll argues that a more plausible theory would place the earliest fungi about 1.5 billion years later than the organisms uncovered by the Swedish Museum of Natural History. Equally skeptical, Doug Erwin, curator of Paleozoic invertebrates at the Smithsonian National Museum of Natural History, stated that the recent discovery, if proven accurate, "would significantly precede fossil evidence and molecular clock analysis for the origin of eukaryotes, much less the origin of fungi." However, study co-author Magnus Ivarsson pointed out that the habitat in which the fungi dwelled while they were still alive would have been an extreme environment devoid of sunlight. "Fungi in this environment most probably lived in symbiosis with microbes utilizing chemically stored energy for their metabolism," he explained. "They may not even have needed free oxygen," Ivarsson added. This is this year's second major discovery in the field of ancient evolution by the Swedish Museum of Natural History. Last month, Tech Times reported that another team, also led by Bengtson, discovered fossil plants estimated to be 1.6 billion years old, which the researchers claimed pre-date any other similar specimens by 400 million years. © 2017 Tech Times, All rights reserved. Do not reproduce without permission.
Holovachov O.,Swedish Museum of Natural History
Biodiversity Data Journal | Year: 2014
We present an updated list of terrestrial and freshwater nematodes from all regions of the Arctic, for which records of properly identified nematode species are available: Svalbard, Jan Mayen, Iceland, Greenland, Nunavut, Northwest territories, Alaska, Lena River estuary, Taymyr and Severnaya Zemlya and Novaya Zemlya. The list includes 391 species belonging to 146 genera, 54 families and 10 orders of the phylum Nematoda. © Holovachov O.
Whitehouse M.J.,Swedish Museum of Natural History
Geostandards and Geoanalytical Research | Year: 2013
High spatial resolution multiple sulfur isotope studies undertaken by multi-collector secondary ion mass spectrometry (SIMS) commonly use well-characterised sulfide reference materials that do not (or are assumed not to) exhibit mass-independent fractionation in 33S and 36S, taking advantage of the three-isotope plot to evaluate the extent of such fractionation in unknown targets. As a result, few studies to date have used a mass independently fractionated reference sulfide to demonstrate accuracy of measurement and/or data reduction procedures. This article evaluates two mass independently fractionated sulfides, a pyrite from the 3.7 Ga Isua greenstone belt and a pyrrhotite from a 2.7 Ga gold deposit in Minas Gerais, Brazil, which may be used to provide additional confidence in the obtained multiple sulfur isotope data. Additionally, the article presents a method for measuring quadruple sulfur isotopes by SIMS at a comparable spatial and volume resolution to that typically employed for triple sulfur isotopes. This method has been applied to the Isua pyrite as well as to a sample of 2.5 Ga pyrite from the Campbellrand, Transvaal, South Africa, previously investigated using SIMS for triple sulfur isotopes, illustrating its potential for quadruple sulfur investigations. © 2012 The Author. Geostandards and Geoanalytical Research © 2012 International Association of Geoanalysts.
Johansson A.,Swedish Museum of Natural History
Precambrian Research | Year: 2014
A refined model of the late Mesoproterozoic to Neoproterozoic supercontinent Rodinia is presented, with Baltica, Amazonia and West Africa attached to eastern Laurentia as in the SAMBA model (Johansson, 2009), and East Antarctica, Australia and India to western Laurentia in a SWEAT configuration (Moores, 1991). In such a model, the Proto-Andean margin of South America would form the conjugate margin of Laurentia's Grenville margin. With the Kalahari craton attached to SW Laurentia and East Antarctica, as proposed by Loewy et al. (2011), followed by the Congo and Tanzania cratons in Africa and the São Fransisco and Rio de la Plata cratons in South America, all these cratons would be part of Rodinia, but would still be separated from Amazonia by a wide Brasiliano (Clymene) ocean embayment. By rotating the African and eastern South American cratons ca. 90° counterclockwise around a pole located close to the Laurentia-Kalahari junction, and East Antarctica, Australia and India ca. 120° counterclockwise around a pole located inside the Kalahari craton, all relative to a fixed Laurentia, these cratons will move from a Rodinia to a Gondwana configuration. These rotations will open up the Proto-Pacific ocean, close the Brasiliano (Clymene) ocean, and both open and close the intervening Adamastor and Mozambique oceans, creating the various Brasiliano and Pan-African fold belts in the ensuing collisions. The maximum plate velocity, ca 7.5. cm/year (15,000. km in 200. m.y.), will occur along the outer periphery of this rotation, thereby explaining the formation of large amounts of juvenile Neoproterozoic continental crust within the oceanic Arabian-Nubian sector of the Pan-African Orogen. Rather than being an example of 'introversion' or 'extroversion', the change from Rodinia to Gondwana in this model would be more like the 90° 'orthoversion' model proposed by Mitchell et al. (2012). © 2013 Elsevier B.V.
McLoughlin S.,Swedish Museum of Natural History
Australian Journal of Botany | Year: 2011
Single, midrib-positioned galls and midrib-flanking oviposition scars are described from four species of Permian glossopterid foliage from Australia and South Africa. Several of these traces have been mistaken previously for glossopterid reproductive organs or fructification detachment scars. A single Early Triassic corystosperm leaf from Australia is reported bearing multiple disc-like galls on both the midrib and pinnules. A Middle Triassic taeniopterid gymnosperm leaf from Australia is described hosting oviposition scars between consecutive secondary veins flanking the midrib. These fossils attest to a much richer record of plantarthropod interactions in the late Palaeozoic and early Mesozoic of high-latitude Gondwana than previously reported, and indicate that herbivory and reproductive strategies involving galling and foliar ovipositioning were re-established relatively soon after the end-Permian mass extinction event that saw major turnovers in both the flora and insect fauna. © 2011 CSIRO.
Bomfleur B.,Swedish Museum of Natural History |
McLoughlin S.,Swedish Museum of Natural History |
Vajda V.,Lund University
Science | Year: 2014
Rapidly permineralized fossils can provide exceptional insights into the evolution of life over geological time. Here, we present an exquisitely preserved, calcified stem of a royal fern (Osmundaceae) from Early Jurassic lahar deposits of Sweden in which authigenic mineral precipitation from hydrothermal brines occurred so rapidly that it preserved cytoplasm, cytosol granules, nuclei, and even chromosomes in various stages of cell division. Morphometric parameters of interphase nuclei match those of extant Osmundaceae, indicating that the genome size of these reputed "living fossils" has remained unchanged over at least 180 million years - a paramount example of evolutionary stasis.
Ericson P.G.P.,Swedish Museum of Natural History
Journal of Biogeography | Year: 2012
Aim To reconstruct the biogeographical history of a large clade of mainly terrestrially adapted birds (coraciiform and piciform birds, owls, diurnal raptors, New World vultures, trogons, mousebirds, cuckoo-rollers, seriemas, parrots and passerines) to test the hypothesis of its Gondwanan origin. Location Global. Methods The phylogenetic tree used in the analysis was a family-level tree estimated from previously published nuclear DNA sequence data. Each family for which a thorough and taxonomically well-sampled phylogenetic analysis exists was subject to an initial dispersal-vicariance analysis in order to reconstruct ancestral areas for its two most basal lineages. Both basal lineages were then used to represent the family in the subsequent reconstruction of ancestral distributions for the entire radiation. Results The analysis showed that three reciprocally monophyletic groups of terrestrial birds have diversified in the Gondwanan land areas of Australia, South America and Africa, respectively. Although each of these three groups may also have originally included other groups, the only survivors today from the Australian radiation are the passerines and parrots, while the falcons and seriemas have survived from the South American radiation. The group of survivors from the African radiation is considerably more taxonomically diverse and includes all coraciiform and piciform birds, owls, diurnal raptors (except falcons), New World vultures, trogons, mousebirds and cuckoo-rollers. Main conclusions The outlined evolutionary scenario with three geographically isolated clades of terrestrial birds is consistent with the available estimates of Late Cretaceous to early Palaeogene dates for these radiations. The diversifications and ecological adaptations within each of the three groups most likely took place in isolation on the different continents. Many cases of convergently evolved adaptations may be revealed through the increased understanding of the phylogenetic relationships of terrestrial birds. © 2011 Blackwell Publishing Ltd.
Pott C.,Swedish Museum of Natural History
International Journal of Plant Sciences | Year: 2014
Premise of research. The concept of Wielandiella angustifolia, a shrub-sized bennettite from the Rhaetian of southern Sweden and East Greenland, became the standard interpretation of the habit and plant architecture of the Williamsoniaceae during the last 100 years. This concept, however, was never critically reinvestigated to evaluate the validity of the restoration. In addition, the new International Code of Nomenclature for algae, fungi, and plants (Melbourne Code) allows erecting fossil taxa for whole-plant concepts, wherefore Wielandiella angustifolia is an ideal candidate. Methodology. The excellently preserved plant fossils were reinvestigated using modern methods, such as cuticular analysis and light, fluorescence, and scanning electron microscopy. Pivotal results. The reinvestigation led to the rejection of the bisexual nature of the plant and provides deeper insights into the plant's nature, biology, and ecology. The rejection of the bisexual nature necessitated emendation of the diagnosis of Wielandiella. Conclusions. The revised diagnosis circumscribes a whole-plant concept that includes branched axes bearing leaves, immature seed cones, and monosporangiate, flowerlike reproductive structures. Good candidates for the hitherto-unidentified microsporangiate structure and the mature seed cone are Bennettistemon and Vardekloeftia, respectively. Discussion of the results concluded that Wielandiella definitely forms a separate genus within the Williamsoniaceae that is distinct from Williamsoniella and Williamsonia. © 2014 by The University of Chicago. All rights reserved.
Hedenas L.,Swedish Museum of Natural History
Botanical Journal of the Linnean Society | Year: 2012
Global phylogeographic patterns in Sanionia uncinata are addressed based on information in internal transcribed spacer (ITS) (214 specimens) and the plastid markers trnL-trnF (221) and rpl16 (217). ITS suggests a monophyletic Sanionia and a paraphyletic S. uncinata; this was neither supported nor rejected by plastid data. Northern or Eastern Eurasia and Alaska appear important in the early evolution of Sanionia and some populations dispersed into the Southern Hemisphere relatively early. Some haplotypes or groups of haplotypes are morphologically and ecologically distinct, biologically meaningful units that correspond with S. orthothecioides, S. symmetrica and S. georgicouncinata s.l. The latter includes two species that are indistinguishable by morphology, S. georgicouncinata s.s. (Southern Hemisphere) and S. nivalis (Northern Hemisphere). Tropical African and South American S. uncinata populations have separate origins and the Southern Hemisphere was colonized at least twice. In the northern circum-Arctic region, the haplotype composition differs between the North Atlantic and Beringian areas. Eastern Eurasia has a higher S. uncinata haplotype diversity than other Holarctic regions, implying less devastating effects of recurrent glacial periods. For Eastern and Western Eurasia, North America and the Southern Hemisphere, most of the haplotype variation was found within the regions, but 14-18% can be referred to among region variation. Plastid haplotype diversity was lower in the Southern Hemisphere than in the Arctic to subarctic, possibly attributable to founder effects. © 2011 The Linnean Society of London.