Ernietta
| Ernietta | ||||||
|---|---|---|---|---|---|---|
| Temporal occurrence | ||||||
| Ediacarium | ||||||
| 550 to 545 million years | ||||||
| Locations | ||||||
| Systematics | ||||||
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| Scientific name | ||||||
| Ernietta | ||||||
| Plow , 1966 | ||||||
| species | ||||||
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Ernietta is a genus of extinct creatures . Their representatives lived at the end of the geological age of the Ediacarium over 545 million years ago. Their fossils show diverse forms that are difficult to compare with those of today's life forms. The systematic classification of Ernitta is therefore considered difficult and is the subject of controversy. In general, Ernietta is considered an early representative of multicellular animals (Metazoa).
features
Fossil finds from Ernietta , including Erniaster , Erniobaris , Erniobeta , Erniocarpus , Erniocentris , Erniocoris , Erniodiscus , Erniofossa , Erniograndis , Ernionorma , Erniopelta , Erniotaxis and Baikalina , which are probably phenotypes of Ernietta plateauensis and show a variety of forms in their size. Ernietta's body showed bilateral or sliding mirror symmetry and had a structure or chambering. Ernietta's body axis was bent into a U-shape, so that the body was tubular or sack-shaped. One line of the back was curved in a zigzag shape.
Way of life
In contrast to most of the other fossils of Ediacaric life forms, which are predominantly preserved as two-dimensional impressions, Ernietta is preserved three-dimensionally in fossilized form. The inside of the body was filled with sand. These fossil finds suggest that Ernietta lived on the ocean floor and that his body was partially buried. It is believed that ernietta to osmotroph malnourished, meaning that the food intake with the help of osmosis was carried out on the body surface.
Systematics
Ernietta is combined with life forms of the Ediacarium with a similar shape, such as Phyllozoon , Pteridinium and Swartpuntia , under the name "Erniettomorph". Their systematic position is the subject of scientific discussions. As a rule, Ernietta is assigned to the realm of the multicellular animals (Metazoa). Due to their symmetry, they can be regarded as the ancestors of today's bilateral animals (Bilateria). Due to their construction, an assignment to the root group of the new mouth animals or the chordates or the acoelomorpha is discussed.
In addition to a systematic classification based on their bilateral symmetry, other classifications are also discussed. Adolf Seilacher assigned Ernietta to the extinct Vendobionts , which he interpreted as large, single-celled living beings.
Individual evidence
- ↑ Plow HD: New fossil remains from the Nama layers in Southwest Africa . In: Paleontological Journal . 40, No. 1, 1966, pp. 14-25. doi : 10.1007 / BF02987628 .
- ↑ Vickers-Rich P, Fedonkin MA, Gehling J et al. : Atlas of precambrian metazoans . In: Fedonkin MA (Ed.): The rise of animals: evolution and diversification of the kingdom animalia . Johns Hopkins University Press, Baltimore 2007, ISBN 0-8018-8679-1 , pp. 257-292.
- ^ Dzik J: Organic membranous skeleton of precambrian metazoans from Namibia . In: Geology . 27, 1999, pp. 519-522.
- ↑ Laflamme M, Xiao S, Kowalewski M: From the Cover: Osmotrophy in modular Ediacara organisms . In: Proc. Natl. Acad. Sci. USA . 106, 2009, pp. 14438-14443. doi : 10.1073 / pnas.0904836106 .
- ↑ Seilacher A, Grazhdankin D, Legouta A: Ediacaran biota: The dawn of animal life in the shadow of giant protists . In: Paleontological Research . 7, No. 1, 2003, pp. 43-54.