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Spongiophyton
''Spongiophyton'' was a thallose fossil of the early to mid-Devonian, which is notoriously difficult to classify. ''Spongiophyton'' displayed dichotomous branching, and a flattened/elliptical cross section with a thick (20–80 μm) upper cuticular surface.Fletcher (2004) It is also perforated with pores resembling those of some liverworts. It probably grew on the banks of rivers. ''Spongiophyton'' has been mistakenly interpreted as tree resin and lycopod cuticle, and was later identified as the cuticle of a thalloid plant. It has most recently been interpreted on morphological and isotopicJahren ''et al.'' (2003) grounds as a lichen—which would place it with Winfrenatia among the earliest known representatives of this group.Retallack (1994) suggested that the Ediacaran biota were lichens, but has since refined this hypothesis (Retallack, 2007). The significance of the isotopic data has, however, been called into question. Jahren ''et al.'' argued that mosses and liv ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Lichen
A lichen ( , ) is a composite organism that arises from algae or cyanobacteria living among filaments of multiple fungi species in a mutualistic relationship.Introduction to Lichens – An Alliance between Kingdoms . University of California Museum of Paleontology. Lichens have properties different from those of their component organisms. They come in many colors, sizes, and forms and are sometimes plant-like, but are not s. They may have tiny, leafless branches (); flat leaf-like structures ( |
Lichens
A lichen ( , ) is a composite organism that arises from algae or cyanobacteria living among hypha, filaments of multiple fungus, fungi species in a mutualism (biology), mutualistic relationship.Introduction to Lichens – An Alliance between Kingdoms . University of California Museum of Paleontology. Lichens have properties different from those of their component organisms. They come in many colors, sizes, and forms and are sometimes plant-like, but are not plants. They may have tiny, leafless branches (fruticose); flat leaf-like structures (foliose); grow crust-like, adhering tightly to a surface (substrate) like a thick coat of paint (crustose); have a powder-like appearance (Leprose lichen, leprose); or other growth forms. A ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
IRMNG
The Interim Register of Marine and Nonmarine Genera (IRMNG) is a taxonomic database which attempts to cover published genus names for all domains of life from 1758 in zoology (1753 in botany) up to the present, arranged in a single, internally consistent taxonomic hierarchy, for the benefit of Biodiversity Informatics initiatives plus general users of biodiversity (taxonomic) information. In addition to containing over 490,000 published genus name instances as at March 2020 (also including subgeneric names in zoology), the database holds over 1.7 million species names (1.3 million listed as "accepted"), although this component of the data is not maintained in as current or complete state as the genus-level holdings. IRMNG can be queried online for access to the latest version of the dataset and is also made available as periodic snapshots or data dumps for import/upload into other systems as desired. Description IRMNG contains scientific names (only) of the genera, a subset of sp ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Ediacaran Biota
The Ediacaran (; formerly Vendian) biota is a Taxonomy (biology), taxonomic period classification that consists of all life forms that were present on Earth during the Ediacaran Period (). These were composed of enigmatic tubular and frond-shaped, mostly sessility (zoology), sessile, organisms. Trace fossils of these organisms have been found worldwide, and represent the earliest known complex multicellular organisms. The Ediacaran biota may have undergone evolutionary radiation in a proposed event called the Avalon explosion, . This was after the Earth had thawed from the Cryogenian period's Snowball Earth, extensive glaciation. This biota largely disappeared with the rapid increase in biodiversity known as the Cambrian explosion. Most of the currently existing body plans of animals first appeared in the fossil, fossil record of the Cambrian rather than the Ediacaran. For macroorganisms, the Cambrian biota appears to have almost completely replaced the organisms that dominate ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Devonian Life
The Devonian ( ) is a geologic period and system of the Paleozoic era, spanning 60.3 million years from the end of the Silurian, million years ago (Mya), to the beginning of the Carboniferous, Mya. It is named after Devon, England, where rocks from this period were first studied. The first significant adaptive radiation of life on dry land occurred during the Devonian. Free-sporing vascular plants began to spread across dry land, forming extensive forests which covered the continents. By the middle of the Devonian, several groups of plants had evolved leaves and true roots, and by the end of the period the first seed-bearing plants appeared. The arthropod groups of myriapods, arachnids and hexapods also became well-established early in this period, after starting their expansion to land at least from the Ordovician period. Fish reached substantial diversity during this time, leading the Devonian to often be dubbed the Age of Fishes. The placoderms began dominating al ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
International Journal Of Plant Sciences
The ''International Journal of Plant Sciences'' covers botanical research including genetics and genomics, developmental and cell biology, biochemistry and physiology, morphology and structure, systematics, plant-microbe interactions, paleobotany, evolution, and ecology. The journal also regularly publishes important symposium proceedings. It is published by the University of Chicago Press. From 1875 to 1876 it was known as the ''Botanical Bulletin'' and from 1876 to 1991 as the ''Botanical Gazette''. The first issue titled ''The International Journal of Plants Sciences'' was dated March 1992 (volume 53, number 1). For the years 1992 and 1993, the journal was published quarterly. The journal was founded by brothers John Merle Coulter and Stanley Coulter. John brought the journal to the University of Chicago when he started the Department of Botany. References External links * * International Journal of Plant Sciencesat SCImago Journal Rank Botanical Gazette / International Jo ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Paleobiology (journal)
Paleobiology is a scientific journal promoting the integration of biology and conventional paleontology Paleontology (), also spelled palaeontology or palæontology, is the scientific study of life that existed prior to, and sometimes including, the start of the Holocene epoch (roughly 11,700 years before present). It includes the study of fossi ..., with emphasis placed on biological or paleobiological processes and patterns. It attracts papers of interest to more than one discipline, and occasionally publishes research on recent organisms when this is of interest to paleontologists. Paleontology journals Academic journals published by learned and professional societies Publications established in 1975 Quarterly journals English-language journals Paleobiology Cambridge University Press academic journals {{paleontology-journal-stub ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Geobiology (journal)
''Geobiology'' is a Peer review, peer-reviewed scientific journal of geobiology published by Wiley-Blackwell. It was established in 2003 as both a print and online journal, with five issues per year. In 2011, the journal became online-only, and increased publication to six times per year. The editor-in-chief is Kurt Konhauser (University of Alberta). Abstracting and indexing The journal is indexed and abstracted in:: According to the ''Journal Citation Reports'', the journal has a 2011 impact factor of 4.111, ranking it 6th out of 170 journals in the category "Geosciences, Multidisciplinary", 11th out of 84 journals in the category "Biology", and 19th out of 205 journals in the category "Environmental Sciences". References External links ''Geobiology'' website Geology journals Biology journals English-language journals Publications established in 2003 Bimonthly journals Wiley-Blackwell academic journals Geobiology {{geology-journal-stub ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Statistical Significance
In statistical hypothesis testing, a result has statistical significance when it is very unlikely to have occurred given the null hypothesis (simply by chance alone). More precisely, a study's defined significance level, denoted by \alpha, is the probability of the study rejecting the null hypothesis, given that the null hypothesis is true; and the ''p''-value of a result, ''p'', is the probability of obtaining a result at least as extreme, given that the null hypothesis is true. The result is statistically significant, by the standards of the study, when p \le \alpha. The significance level for a study is chosen before data collection, and is typically set to 5% or much lower—depending on the field of study. In any experiment or observation that involves drawing a sample from a population, there is always the possibility that an observed effect would have occurred due to sampling error alone. But if the ''p''-value of an observed effect is less than (or equal to) the significanc ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Isotopic Signature
An isotopic signature (also isotopic fingerprint) is a ratio of non-radiogenic ' stable isotopes', stable radiogenic isotopes, or unstable radioactive isotopes of particular elements in an investigated material. The ratios of isotopes in a sample material are measured by isotope-ratio mass spectrometry against an isotopic reference material. This process is called isotope analysis. Stable isotopes The atomic mass of different isotopes affect their chemical kinetic behavior, leading to natural isotope separation processes. Carbon isotopes For example, different sources and sinks of methane have different affinity for the 12C and 13C isotopes, which allows distinguishing between different sources by the 13C/12C ratio in methane in the air. In geochemistry, paleoclimatology and paleoceanography this ratio is called δ13C. The ratio is calculated with respect to Pee Dee Belemnite (PDB) standard: :\delta \ce_\mathrm = \left(\frac - 1\right) \cdot 1000 ‰ Similarly, carbon ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Bryophyte
The Bryophyta s.l. are a proposed taxonomic division containing three groups of non-vascular land plants (embryophytes): the liverworts, hornworts and mosses. Bryophyta s.s. consists of the mosses only. They are characteristically limited in size and prefer moist habitats although they can survive in drier environments. The bryophytes consist of about 20,000 plant species. Bryophytes produce enclosed reproductive structures (gametangia and sporangia), but they do not produce flowers or seeds. They reproduce sexually by spores and asexually by fragmentation or the production of gemmae. Though bryophytes were considered a paraphyletic group in recent years, almost all of the most recent phylogenetic evidence supports the monophyly of this group, as originally classified by Wilhelm Schimper in 1879. The term ''bryophyte'' comes . Terminology The term "Bryophyta" was first suggested by Braun in 1864. G.M. Smith placed this group between Algae and Pteridophyta. Features The d ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Marchantiophyta
The Marchantiophyta () are a division of non-vascular land plants commonly referred to as hepatics or liverworts. Like mosses and hornworts, they have a gametophyte-dominant life cycle, in which cells of the plant carry only a single set of genetic information. It is estimated that there are about 9000 species of liverworts. Some of the more familiar species grow as a flattened leafless thallus, but most species are leafy with a form very much like a flattened moss. Leafy species can be distinguished from the apparently similar mosses on the basis of a number of features, including their single-celled rhizoids. Leafy liverworts also differ from most (but not all) mosses in that their leaves never have a costa (present in many mosses) and may bear marginal cilia (very rare in mosses). Other differences are not universal for all mosses and liverworts, but the occurrence of leaves arranged in three ranks, the presence of deep lobes or segmented leaves, or a lack of clearly diff ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
