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Petalonamae
The petalonamids (Petalonamae) are an extinct group of archaic animals typical of the Ediacaran biota, also called frondomorphs, dating from approximately 635 million years ago to 516 million years ago. They are benthic and motionless animals, that have the shape of leaves, fronds (frondomorphic), feathers or spindles and were initially considered algae, octocorals or sea pens. It is now believed that there are no living descendants of the group, which shares a probable relation to the Ediacaran animals known as Vendozoans. It is considered that the organisms were fluffy at least in appearance, as if "inflatable." They are particularly difficult to classify phylogenetically. Lacking mouths, intestines, reproductive organs, and with no preserved evidence of internal structures, these organisms' existence is very strange by current standards. The most widely accepted hypothesis is that they could suck nutrients from the water around them by osmosis. The fronds were composed of bra ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Vendobionta
Vendobionts or Vendozoans (Vendobionta) are a proposed very high-level, extinct clade of benthic organisms that made up of the majority of the organisms that were part of the Ediacaran biota. It is a hypothetical group and at the same time, it would be the oldest of the animals that populated the Earth about 580 million years ago, in the Ediacaran period (formerly ''Vendian''). They became extinct shortly after the so-called Cambrian explosion, with the introduction of fauna formed by more recognizable groups and more related to modern animals. It is very likely that the whole Ediacaran biota is not a monophyletic clade and not every genus placed in its subtaxa is an animal. This biological group is not widely recognized; credibility is limited by the expansive speculation needed to establish phylogenetic relationships between such ancient extinct groups. The hypothesis was formulated by the German geologist Adolf Seilacher, who even doubts its relationship with the animal k ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Pambikalbae
''Pambikalbae'' is a monospecific genus known from the Ediacaran Period (approximately 555 million years ago) of South Australia. Its morphology resembles the morphology of colonial cnidarians, such as sea pens or siphonophores. Description ''Pambikalbae'' had a broad, frondose-shaped body composed of multiple vanes extending from an axial stem, and containing a serial series of chambers. Specimens of ''Pambikalbae'' found thus far have measured approximately 20 to 30 cm in length, with a width of 12 cm at the widest point of the frondose-body, and 6.6 cm wide at the stem. Diversity ''Pambikalbae'' is a monospecific genus, with only one known species, ''Pambikalbae hasenohrae''. Discovery ''Pambikalbae hasenohrae'' was discovered within a fossiliferous exposure on the Nilpena pastoral property in the Flinders Ranges in South Australia. Pamela Hasenohr, an amateur geologist, found and brought the ''Pambikalbae'' fossils to the attention of Richard Jenkins, ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
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 the beginning of the Phanerozoic Eon. It is named after the Ediacara Hills of South Australia. The Ediacaran Period's status as an official geological period was ratified in 2004 by the International Union of Geological Sciences (IUGS), making it the first new geological period declared in 120 years. Although the period takes its name from the Ediacara Hills where geologist Reg Sprigg first discovered fossils of the eponymous Ediacaran biota in 1946, the type section is located in the bed of the Enorama Creek within Brachina Gorge in the Flinders Ranges of South Australia, at . The Ediacaran marks the first appearance of widespread multicellular fauna following the end of Snowball Earth glaciation events, the so-called Ediacaran biota, ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Arboreomorpha
The arboreomorphs (Arboreomorpha) are ediacaran beings of the frondomorph type that had a disk or bulb-shaped anchor on the ocean floor, a central stem and branching. The "branches" were smooth, tubular structures, often swollen with bifurcation and connected together to form a leaf-like structure. ''Thaumaptilon'' is considered as one of the few cases that reached the Cambrian, though its placement is controversial. Some authors classify this group within Rangeomorpha The rangeomorphs are a form taxon of frondose Ediacaran fossils that are united by a similarity to ''Rangea''. Some researchers, such as Pflug and Narbonne, suggest that a natural taxon Rangeomorpha may include all similar-looking fossils. Ra ... and others together with Erniettomorpha in a larger group called Frondomorpha. References Petalonamae Ediacaran Ediacaran life Aquatic animals {{Ediacaran-stub ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Rangea
''Rangea'' is a frond-like Ediacaran fossil with six-fold radial symmetry. It is the type genus of the rangeomorphs. ''Rangea'' was the first complex Precambrian macrofossil named and described anywhere in the world. ''Rangea'' was a centimetre- to decimetre-scale frond characterised by a repetitive pattern of self-similar branches and a sessile benthic lifestyle. Fossils are typically preserved as moulds and casts exposing only a leafy petalodium, and the rarity and incompleteness of specimens has made it difficult to reconstruct the three-dimensional (3D) morphology of the entire organism.Sharp, Alana C., Alistair R. Evans, Siobhan A. Wilson, and Patricia Vickers-Rich. "First Non-destructive Internal Imaging of Rangea, an Icon of Complex Ediacaran Life." Precambrian Research 299 (2017): 303-08. doi: 10.1016/j.precamres.2017.07.023 Fossilized ''Rangea'' consists of several vanes. Each vane has a foliate shape with a series of recessed furrows that run outwards at varying angles ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Pteridinium
''Pteridinium'' is an erniettomorph found in a number of Precambrian deposits worldwide. It is a member of the Ediacaran biota. Body plan The three-lobed body is generally flat such that only two lobes are visible. Each lobe consists of a number of parallel ribs extending back to the main axis where the three lobes come together. Even on well-preserved specimens, there is no sign of a mouth, anus, eyes, legs, antennae, or any other appendages or organs. The organism grew primarily by the addition of new units, probably at both ends, with the inflation of existing units contributing little to its growth. Ecology Specimens found in what is thought to be life positions indicate that the creature rested on — or possibly in — the sediment in shallow seas. No tracks are known that would seem to be consistent with a moving ''Pteridinium''. It is unclear whether it performed photosynthesis, or osmotically extracted nutrients from seawater. Occurrence Fossils are common in late Preca ... [...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] |
Erniettomorph
The Erniettomorphs are a form of Ediacaran fossil consisting of rows of airbed-like tubes arranged along a midline with a glide symmetry. Representative genera include '' Ernietta'', '' Phyllozoon'', ''Pteridinium'', ''Swartpuntia''. Undisputed Erniettomorphs were Ediacaran, but the species '' Erytholus'', ''Rutgersella'', and ''Protonympha'', who have by some been included in this group but are by no means clear members, are found through to the Late Devonian . Their affinity is uncertain; they probably form a clade and are most likely a sister group to the rangeomorphs, which bear a similar (though fractal) construction. Placements within the metazoan crown-group have been rebutted, and it is most likely that these peculiar organisms lie in the stem group to the animals. There is no evidence that they possessed a mouth or gut. Because they may have been found in water which was too deep to permit photosynthesis – and in some cases, lived half-buried in sediment, it is spe ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Erniettomorpha
The Erniettomorphs are a form of Ediacaran fossil consisting of rows of airbed-like tubes arranged along a midline with a glide symmetry. Representative genera include ''Ernietta'', ''Phyllozoon'', ''Pteridinium'', ''Swartpuntia''. Undisputed Erniettomorphs were Ediacaran, but the species '' Erytholus'', ''Rutgersella'', and ''Protonympha'', who have by some been included in this group but are by no means clear members, are found through to the Late Devonian . Their affinity is uncertain; they probably form a clade and are most likely a sister group to the rangeomorphs, which bear a similar (though fractal) construction. Placements within the metazoan crown-group have been rebutted, and it is most likely that these peculiar organisms lie in the stem group to the animals. There is no evidence that they possessed a mouth or gut. Because they may have been found in water which was too deep to permit photosynthesis – and in some cases, lived half-buried in sediment, it is specul ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Rangeomorpha
The rangeomorphs are a form taxon of frondose Ediacaran Ediacaran biota, fossils that are united by a similarity to ''Rangea''. Some researchers, such as Pflug and Narbonne, suggest that a natural taxon Rangeomorpha may include all similar-looking fossils. Rangeomorphs appear to have had an effective reproductive strategy, based on analysis of the distribution pattern of ''Fractofusus misrai'', which consisted of sending out a waterborne asexual propagule to a distant area, and then spreading rapidly from there, just as plants today spread by stolons or runners. Rangeomorphs are a key part of the Ediacaran biota, which survived about 30 million years, until the base of the Cambrian, which was . They were especially abundant in the early Ediacaran Mistaken Point assemblage found in Newfoundland (island), Newfoundland. Body plan Rangeomorphs consist of branching "frond" elements, each a few centimetres long, each of which is composed of many smaller branching tubes held up by ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Stromatoveris
''Stromatoveris psygmoglena'' is a genus of basal petalonam from the Chengjiang deposits of Yunnan that was originally aligned with the fossil ''Charnia'' (strictly, the Charniomorpha) from the Ediacara biota. However, such an affinity is developmentally implausible and ''S. psygmoglena'' is now thought to be either a sessile basal ctenophore, or a sessile organism closely related to ctenophores. Nevertheless, a 2018 phylogenetic analysis by Jennifer Hoyal Cuthill and Jian Han indicated that ''Stromatoveris'' was a member of Animalia and closely related to ediacaran frond-like lifeforms. Distribution Cambrian of China China, officially the People's Republic of China (PRC), is a country in East Asia. It is the world's most populous country, with a population exceeding 1.4 billion, slightly ahead of India. China spans the equivalent of five time zones and .... References {{Taxonbar, from1=Q7624360, from2=Q107049706 Cambrian invertebrates Maotianshan shales fossils ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Namibia
Namibia (, ), officially the Republic of Namibia, is a country in Southern Africa. Its western border is the Atlantic Ocean. It shares land borders with Zambia and Angola to the north, Botswana to the east and South Africa to the south and east. Although Kazungula, it does not border Zimbabwe, less than 200 metres (660 feet) of the Botswanan right bank of the Zambezi, Zambezi River separates the two countries. Namibia gained independence from South Africa on 21 March 1990, following the Namibian War of Independence. Its capital and largest city is Windhoek. Namibia is a member state of the United Nations (UN), the Southern African Development Community (SADC), the African Union (AU) and the Commonwealth of Nations. The driest country in sub-Saharan Africa, Namibia has been inhabited since pre-historic times by the San people, San, Damara people, Damara and Nama people. Around the 14th century, immigration, immigrating Bantu peoples arrived as part of the Bantu expansion. Since ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
