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Balanoglossus Borealis
''Balanoglossus'' is a genus of ocean-dwelling acorn worms. It has zoological importance because, being hemichordates, they are an "evolutionary link" between invertebrates and vertebrates. ''Balanoglossus'' specimens are deuterostomes, and resemble the chordates in that they possess branchial openings. Their heads are between 2.5 mm (1/10 in) and 5 mm (1/5 in) wide. Discovery Johann Friedrich von Eschscholtz discovered ''Balanoglossus'' in 1825 on Mashail Island, and described it as a worm-like holothurian. The discovery of gill slits in these animals by Alexander Kovalevsky (1865) led to the creation of the class Enteropneusta by Carl Gegenbaur (1870). Classification William Bateson (1885) originally included them in phylum Chordata. Hyman (1959), however, placed them near Echinodermata and gave Hemichordata a status of an independent phylum. Habitat ''Balanoglossus'' are burrowing, exclusively marine animals. They are found in shallow waters betwe ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Réunion
Réunion (; ; ; known as before 1848) is an island in the Indian Ocean that is an overseas departments and regions of France, overseas department and region of France. Part of the Mascarene Islands, it is located approximately east of the island of Madagascar and southwest of the island of Mauritius. , it had a population of 896,175. Its capital and largest city is Saint-Denis, La Réunion, Saint-Denis. Réunion was uninhabited until French immigrants and colonial subjects settled the island in the 17th century. Its tropical climate led to the development of a plantation economy focused primarily on sugar; slaves from East Africa were imported as fieldworkers, followed by Malays, Annamite, Vietnamese, Chinese, and Indians as indentured laborers. Today, the greatest proportion of the population is of mixed descent, while the predominant language is Réunion Creole, though French remains the sole official language. Since 1946, Réunion has been governed as a regions of France, ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Carl Gegenbaur
Carl Gegenbaur (21 August 1826 – 14 June 1903)"Carl Gegenbaur – Encyclopædia Britannica" (biography), ''Encyclopædia Britannica'', 2006, Britannica.coBritannica-KarlG was a German anatomist and professor who demonstrated that the field of comparative anatomy offers important evidence supporting of the theory of evolution. As a professor of anatomy at the University of Jena (1855–1873) and at the University of Heidelberg (1873–1903), Carl Gegenbaur was a strong supporter of Charles Darwin's theory of organic evolution, having taught and worked, beginning in 1858, with Ernst Haeckel, eight years his junior. Gegenbaur's book ''Grundzüge der vergleichenden Anatomie'' (1859; English translation ''Elements of Comparative Anatomy'' by Francis Jeffrey Bell, 1878) became the standard textbook, at the time, of evolutionary morphology, emphasizing that structural similarities among various animals provide clues to their evolutionary history. Gegenbaur noted that the most reliab ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Balanoglossus Australiensis
''Balanoglossus australiensis'' is a species of long acorn worm in Ptychoderidae family which can be found in Gulf of Carpentaria, New Zealand, Australian cities such as Hawkesbury and Manning as well as Solomon Archipelago and its sea A sea is a large body of salt water. There are particular seas and the sea. The sea commonly refers to the ocean, the interconnected body of seawaters that spans most of Earth. Particular seas are either marginal seas, second-order section .... Their habitat consists of deep sandy burrows where they feed on '' Ubius'' species. References Enteropneusta Animals described in 1894 Invertebrates of Australia {{Hemichordate-stub ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Species
A species () is often defined as the largest group of organisms in which any two individuals of the appropriate sexes or mating types can produce fertile offspring, typically by sexual reproduction. It is the basic unit of Taxonomy (biology), classification and a taxonomic rank of an organism, as well as a unit of biodiversity. Other ways of defining species include their karyotype, DNA sequence, morphology (biology), morphology, behaviour, or ecological niche. In addition, palaeontologists use the concept of the chronospecies since fossil reproduction cannot be examined. The most recent rigorous estimate for the total number of species of eukaryotes is between 8 and 8.7 million. About 14% of these had been described by 2011. All species (except viruses) are given a binomial nomenclature, two-part name, a "binomen". The first part of a binomen is the name of a genus to which the species belongs. The second part is called the specific name (zoology), specific name or the specific ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
World Register Of Marine Species
The World Register of Marine Species (WoRMS) is a taxonomic database that aims to provide an authoritative and comprehensive catalogue and list of names of marine organisms. Content The content of the registry is edited and maintained by scientific specialists on each group of organism. These taxonomists control the quality of the information, which is gathered from the primary scientific literature as well as from some external regional and taxon-specific databases. WoRMS maintains valid names of all marine organisms, but also provides information on synonyms and invalid names. It is an ongoing task to maintain the registry, since new species are constantly being discovered and described by scientists; in addition, the nomenclature and taxonomy of existing species is often corrected or changed as new research is constantly being published. Subsets of WoRMS content are made available, and can have separate badging and their own home/launch pages, as "subregisters", such as th ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Marine Life
Marine life, sea life or ocean life is the collective ecological communities that encompass all aquatic animals, aquatic plant, plants, algae, marine fungi, fungi, marine protists, protists, single-celled marine microorganisms, microorganisms and associated marine virus, viruses living in the saline water of marine habitats, either the sea water of marginal seas and oceans, or the brackish water of coastal wetlands, lagoons, estuary, estuaries and inland seas. , more than 242,000 marine species have been documented, and perhaps two million marine species are yet to be documented. An average of 2,332 new species per year are being described. Marine life is studied scientifically in both marine biology and in biological oceanography. By volume, oceans provide about 90% of the living space on Earth, and served as the cradle of life and vital biotic sanctuaries throughout Earth's geological history. The earliest known life forms evolved as anaerobe, anaerobic prokaryotes (archaea ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Hemichordata
Hemichordata ( ) is a phylum which consists of triploblastic, eucoelomate, and bilaterally symmetrical marine deuterostome animals, generally considered the sister group of the echinoderms. They appear in the Lower or Middle Cambrian and include two main classes: Enteropneusta (acorn worms), and Pterobranchia. A third class, Planctosphaeroidea, is known only from the larva of a single species, '' Planctosphaera pelagica''. The class Graptolithina, formerly considered extinct, is now placed within the pterobranchs, represented by a single living genus '' Rhabdopleura''. Acorn worms are solitary worm-shaped organisms. They generally live in burrows (the earliest secreted tubes) and are deposit feeders, but some species are pharyngeal filter feeders, while the family are free living detritivores. Many are well known for their production and accumulation of various halogenated phenols and pyrroles. Pterobranchs are filter-feeders, mostly colonial, living in a collagenous ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Echinodermata
An echinoderm () is any animal of the phylum Echinodermata (), which includes starfish, brittle stars, sea urchins, sand dollars and sea cucumbers, as well as the sessile sea lilies or "stone lilies". While bilaterally symmetrical as larvae, as adults echinoderms are recognisable by their usually five-pointed radial symmetry (pentamerous symmetry), and are found on the sea bed at every ocean depth from the intertidal zone to the abyssal zone. The phylum contains about 7,600 living species, making it the second-largest group of deuterostomes after the chordates, as well as the largest marine animal, marine-only phylum. The first definitive echinoderms appeared near the start of the Cambrian. Echinoderms are important both ecologically and geologically. Ecologically, there are few other groupings so abundant in the deep sea, as well as continental shelf, shallower oceans. Most echinoderms are able to asexual reproduction, reproduce asexually and regeneration (biology), regenerat ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Chordata
A chordate ( ) is a bilaterian animal belonging to the phylum Chordata ( ). All chordates possess, at some point during their larval or adult stages, five distinctive physical characteristics (Apomorphy and synapomorphy, synapomorphies) that distinguish them from other Taxon, taxa. These five synapomorphies are a notochord, a neural tube, hollow dorsal nerve cord, an endostyle or thyroid, pharyngeal slits, and a post-anus, anal tail. In addition to the morphological characteristics used to define chordates, analysis of genome sequences has identified two conserved signature indels (CSIs) in their proteins: cyclophilin-like protein and inner mitochondrial membrane protease ATP23, which are exclusively shared by all vertebrates, tunicates and cephalochordates. These CSIs provide molecular means to reliably distinguish chordates from all other animals. Chordates are divided into three phylum, subphyla: Vertebrata (fish, amphibians, reptiles, birds and mammals), whose notochor ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Phylum
In biology, a phylum (; : phyla) is a level of classification, or taxonomic rank, that is below Kingdom (biology), kingdom and above Class (biology), class. Traditionally, in botany the term division (taxonomy), division has been used instead of phylum, although the International Code of Nomenclature for algae, fungi, and plants accepts the terms as equivalent. Depending on definitions, the animal kingdom Animalia contains about 31 phyla, the plant kingdom Plantae contains about 14 phyla, and the fungus kingdom Fungi contains about eight phyla. Current research in phylogenetics is uncovering the relationships among phyla within larger clades like Ecdysozoa and Embryophyta. General description The term phylum was coined in 1866 by Ernst Haeckel from the Greek (, "race, stock"), related to (, "tribe, clan"). Haeckel noted that species constantly evolved into new species that seemed to retain few consistent features among themselves and therefore few features that distinguishe ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
William Bateson
William Bateson (8 August 1861 – 8 February 1926) was an English biologist who was the first person to use the term genetics to describe the study of heredity, and the chief populariser of the ideas of Gregor Mendel following their rediscovery in 1900 by Hugo de Vries and Carl Correns. His 1894 book ''Materials for the Study of Variation'' was one of the earliest formulations of the new approach to genetics. Early life and education Bateson was born 1861 in Whitby on the Yorkshire coast, the son of William Henry Bateson, Master of St John's College, Cambridge, and Anna Bateson, Anna Bateson (née Aikin), who was on the first governing body of Newnham College, Cambridge. He was educated at Rugby School and at St John's College, where he graduated BA in 1883 with a first in natural sciences. Taking up embryology, he went to the United States to investigate the development of ''Balanoglossus'', a worm-like hemichordate which led to his interest in vertebrate origins. In 1883 ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
