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Horodyskia
''Horodyskia'' is a fossilised organism found in rocks dated from to . Its shape has been described as a "string of beads" connected by a very fine thread. It is considered one of the oldest known eukaryotes. Biology Comparisons of different fossils in the same locations suggest that it rearranged itself into fewer but larger main masses as the sediment grew deeper round its base. It may also have had a series of holdfasts along the bottom of the thread. Dimple marks in offshore sandstone have been found in the same deposits as ''Horodyskia'', suggesting that they may be remnants of older holdfasts. Thin sections of ''Horodyskia'' have revealed a system of tubes within the beads, including connecting strings, and other tubes radiating outward from each bead. Partial burial and branching of these tubes suggest that it may have had a benthic sessile lifestyle. Members of the genus are distinguished by bead size and spacing, with the beads of ''H. moniliformi''s being larger ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Horodyskia Per Fedonkin 2003
''Horodyskia'' is a fossilised organism found in rocks dated from to . Its shape has been described as a "string of beads" connected by a very fine thread. It is considered one of the oldest known eukaryotes. Biology Comparisons of different fossils in the same locations suggest that it rearranged itself into fewer but larger main masses as the sediment grew deeper round its base. It may also have had a series of holdfasts along the bottom of the thread. Dimple marks in offshore sandstone have been found in the same deposits as ''Horodyskia'', suggesting that they may be remnants of older holdfasts. Thin sections of ''Horodyskia'' have revealed a system of tubes within the beads, including connecting strings, and other tubes radiating outward from each bead. Partial burial and branching of these tubes suggest that it may have had a benthic sessile lifestyle. Members of the genus are distinguished by bead size and spacing, with the beads of ''H. moniliformi''s being larger ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Horodyskia Variation
''Horodyskia'' is a fossilised organism found in rocks dated from to . Its shape has been described as a "string of beads" connected by a very fine thread. It is considered one of the oldest known eukaryotes. Biology Comparisons of different fossils in the same locations suggest that it rearranged itself into fewer but larger main masses as the sediment grew deeper round its base. It may also have had a series of holdfasts along the bottom of the thread. Dimple marks in offshore sandstone have been found in the same deposits as ''Horodyskia'', suggesting that they may be remnants of older holdfasts. Thin sections of ''Horodyskia'' have revealed a system of tubes within the beads, including connecting strings, and other tubes radiating outward from each bead. Partial burial and branching of these tubes suggest that it may have had a benthic sessile lifestyle. Members of the genus are distinguished by bead size and spacing, with the beads of ''H. moniliformi''s being larger ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Archaeosporales
Archaeosporales is an order of fungi best known as arbuscular mycorrhiza to vascular land plants (Tracheophyta). But also form free living endocyte symbioses with cyanobacteria. The free living forms have a Precambrian fossil record back 2.2 Ga, well before evolution of Tracheophyta Vascular plants (), also called tracheophytes () or collectively Tracheophyta (), form a large group of land plants ( accepted known species) that have lignified tissues (the xylem) for conducting water and minerals throughout the plant. They a .... References Glomeromycota Fungus orders {{fungus-stub ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Francevillian B Formation
The Francevillian B Formation, also known as the Francevillian Formation or FB2 in scientific research, is a geologic formation of black shale provinces close to the town of Franceville, Gabon. The formation was deposited between 2.14-2.08 Ga (billion years ago) in the Palaeoproterozoic, and is a unique shale among others from that time frame because (unlike other black shale provinces formed at that time) the ''Francevillian Formation'' has not experienced any thermal overprinting due to diagenesis after burial nor significant metamorphism since it was deposited. The ''Francevillian B Formation'' is important to the field of palaeontology because it contains fossil material of possible eukaryotic organisms from around 2.1 Ga which have been informally dubbed the "''Francevillian biota''" or "'' Gabonionta''". This biota takes on the appearance of a multitude of forms such as discs with ruffled rides, ruffled blobs, "stalked/tailed flowers" and strings of beads that were interpr ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Glomeromycota
Glomeromycota (often referred to as glomeromycetes, as they include only one class, Glomeromycetes) are one of eight currently recognized divisions within the kingdom Fungi, with approximately 230 described species. Members of the Glomeromycota form arbuscular mycorrhizas (AMs) with the thalli of bryophytes and the roots of vascular land plants. Not all species have been shown to form AMs, and one, ''Geosiphon pyriformis'', is known not to do so. Instead, it forms an endocytobiotic association with ''Nostoc'' cyanobacteria. The majority of evidence shows that the Glomeromycota are dependent on land plants (''Nostoc'' in the case of ''Geosiphon'') for carbon and energy, but there is recent circumstantial evidence that some species may be able to lead an independent existence. The arbuscular mycorrhizal species are terrestrial and widely distributed in soils worldwide where they form symbioses with the roots of the majority of plant species (>80%). They can also be found in wetla ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
List Of Ediacaran Genera ...
This is a list of all described Ediacaran genera, including the Ediacaran biota. It contains 227 genera. References {{reflist, 30em * Ediacaran The Ediacaran Period ( ) is a geological period that spans 96 million years from the end of the Cryogenian Period 635 million years ago (Mya), to the beginning of the Cambrian Period 538.8 Mya. It marks the end of the Proterozoic Eon, and th ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Calymmian
The Calymmian Period (from grc, κάλυμμα, kálymma, meaning "cover") is the first geologic period in the Mesoproterozoic Era and lasted from Mya to Mya (million years ago). Instead of being based on stratigraphy, these dates are defined chronometrically. The period is characterised by expansion of existing platform covers, or by new platforms on recently cratonized basements. The supercontinent In geology, a supercontinent is the assembly of most or all of Earth's continental blocks or cratons to form a single large landmass. However, some geologists use a different definition, "a grouping of formerly dispersed continents", which leav ... Columbia started to break during the Calymmian some 1500 Mya. See also * * References * * Mesoproterozoic Geological periods Proterozoic geochronology {{geochronology-stub ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Foraminifera
Foraminifera (; Latin for "hole bearers"; informally called "forams") are single-celled organisms, members of a phylum or class of amoeboid protists characterized by streaming granular Ectoplasm (cell biology), ectoplasm for catching food and other uses; and commonly an external shell (called a "Test (biology), test") of diverse forms and materials. Tests of chitin (found in some simple genera, and Textularia in particular) are believed to be the most primitive type. Most foraminifera are marine, the majority of which live on or within the seafloor sediment (i.e., are benthos, benthic), while a smaller number float in the water column at various depths (i.e., are planktonic), which belong to the suborder Globigerinina. Fewer are known from freshwater or brackish conditions, and some very few (nonaquatic) soil species have been identified through molecular analysis of small subunit ribosomal DNA. Foraminifera typically produce a test (biology), test, or shell, which can have eithe ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Fossils Of China
A fossil (from Classical Latin , ) is any preserved remains, impression, or trace of any once-living thing from a past geological age. Examples include bones, shells, exoskeletons, stone imprints of animals or microbes, objects preserved in amber, hair, petrified wood and DNA remnants. The totality of fossils is known as the ''fossil record''. Paleontology is the study of fossils: their age, method of formation, and evolutionary significance. Specimens are usually considered to be fossils if they are over 10,000 years old. The oldest fossils are around 3.48 billion years old to 4.1 billion years old. Early edition, published online before print. The observation in the 19th century that certain fossils were associated with certain rock strata led to the recognition of a geological timescale and the relative ages of different fossils. The development of radiometric dating techniques in the early 20th century allowed scientists to quantitatively measure the absolute ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Francevillian Biota
The Francevillian biota (also known as Gabon macrofossils or Gabonionta) is a group of 2.1-billion-year-old Palaeoproterozoic, macroscopic organisms known from fossils found in Gabon in the Palaeoproterozoic Francevillian B Formation, a black shale province. The fossils are postulated to be evidence of the earliest form of multicellular life. They were discovered by an international team led by the Moroccan-French geologist Abderrazak El Albani, of the University of Poitiers, France. While they have yet to be assigned to a formal taxonomic position, they have been informally and collectively referred to as the "Gabonionta" by the Natural History Museum Vienna in 2014. Morphology The fossil organisms are up to in size. Their bodies were flattened disks with a characteristic morphology, including circular and elongated individuals. A spherical to ellipsoidal central body is bounded by radial structures. The fossils show three-dimensionality and coordinated growth. Cell-cell comm ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Fungus
A fungus ( : fungi or funguses) is any member of the group of eukaryotic organisms that includes microorganisms such as yeasts and molds, as well as the more familiar mushrooms. These organisms are classified as a kingdom, separately from the other eukaryotic kingdoms, which by one traditional classification include Plantae, Animalia, Protozoa, and Chromista. A characteristic that places fungi in a different kingdom from plants, bacteria, and some protists is chitin in their cell walls. Fungi, like animals, are heterotrophs; they acquire their food by absorbing dissolved molecules, typically by secreting digestive enzymes into their environment. Fungi do not photosynthesize. Growth is their means of mobility, except for spores (a few of which are flagellated), which may travel through the air or water. Fungi are the principal decomposers in ecological systems. These and other differences place fungi in a single group of related organisms, named the ''Eumycota'' (''true f ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Geosiphon
''Geosiphon'' is a genus of fungus in the family Geosiphonaceae. The genus is monotypic, containing the single species ''Geosiphon pyriformis'', first described by Kützing in 1849 as ''Botrydium pyriforme''. In 1915, Von Wettstein characterized ''Geosiphon pyriforme'' as a multinucleate alga containing endosymbiotic cyanobacteria, although he also noted the presence of chitin, a component of fungal cell walls. In 1933, Knapp was the first to suggest the fungal origin of the species and described it as a lichen with endosymbiotic cyanobacteria. It is the only member of the Glomeromycota known to not form a symbiosis with terrestrial plants in the form of arbuscular mycorrhiza. Life cycle ''Geosiphon pyriformis'' is known for being the symbiont of ''Nostoc''. The ''Geosiphon''-''Nostoc'' symbiosis, as by modern definitions, is not a lichen, since it is an intracellular association. Also, by functional and evolutionary implications it is more comparable to the arbuscular mycorrhiza ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
