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Takikawa Sea Cow
The Takikawa sea cow (''Hydrodamalis spissa'') is an extinct herbivorous marine mammal of the Late Pliocene which was closely related to the recently extinct Steller's sea cow (''H. gigas''). In 1988, fossils of sea cows were discovered in Hokkaido and were originally assigned to the Takikawa sea cow, a newly described species, even though this taxon is thought of by some scientists as a synonym of the Cuesta sea cow The Cuesta sea cow (''Hydrodamalis cuestae'') is an extinct Herbivore, herbivorous marine mammal and is the direct ancestor of the Steller's sea cow (''Hydrodamalis gigas''). They reached up to in length, making them among the biggest sirenians ... (''H. cuestae''). It is uncertain whether or not the Takikawa sea cow was simply a local variant of the Cuesta sea cow or a completely separate lineage. However, the Steller's sea cow and Takikawa sea cow share more morphological similarities than the Takikawa sea cow and Cuesta sea cow. References Hydrodamal ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Late Pliocene
Late or LATE may refer to: Everyday usage * Tardy, or late, not being on time * Late (or the late) may refer to a person who is dead Music * Late (The 77s album), ''Late'' (The 77s album), 2000 * Late (Alvin Batiste album), 1993 * Late!, a pseudonym used by Dave Grohl on his ''Pocketwatch (album), Pocketwatch'' album * Late (rapper), an underground rapper from Wolverhampton * "Late", a song by Kanye West from ''Late Registration'' Other uses * Late (Tonga), an uninhabited volcanic island southwest of Vavau in the kingdom of Tonga * Late (The Handmaid's Tale), "Late" (''The Handmaid's Tale''), a television episode * LaTe, Laivateollisuus, Oy Laivateollisuus Ab, a defunct shipbuilding company * Limbic-predominant age-related TDP-43 encephalopathy, a proposed form of dementia * Local-authority trading enterprise, a New Zealand business law * Local average treatment effect, a concept in econometrics * Late, a synonym for ''cooler'' in Stellar classification#"Early" and "late" nomencla ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Cuesta Sea Cow
The Cuesta sea cow (''Hydrodamalis cuestae'') is an extinct Herbivore, herbivorous marine mammal and is the direct ancestor of the Steller's sea cow (''Hydrodamalis gigas''). They reached up to in length, making them among the biggest sirenians to have ever lived. They were first described in 1978 by Daryl Domning when fossils in California were unearthed. Its appearance and behavior are largely based on that of the well-documented Steller's sea cow, which, unlike the Cuesta sea cow, lived into the modern era and was well-described. Taxonomy and extinction The fossils of the Cuesta sea cow were first discovered in the Late Pliocene sediment formations of Pismo Beach, California in 1978, and successive finds of the species were unearthed elsewhere in California. In 1988, fossils of sea cows were discovered in Hokkaido that were originally assigned to the Takikawa sea cow (''H. spissa''), a newly-described species, but this is thought of by some scientists as a synonym (taxonomy) ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Pliocene Sirenians
The Pliocene ( ; also Pleiocene) is the epoch in the geologic time scale that extends from 5.33 to 2.58See the 2014 version of the ICS geologic time scale million years ago (Ma). It is the second and most recent epoch of the Period in the . The Pliocene follows the Epoch and is followed by the |
Hydrodamalis
''Hydrodamalis'' is a genus of extinct herbivorous sirenian marine mammals. It included the Steller's sea cow (''Hydrodamalis gigas''), the Cuesta sea cow (''Hydrodamalis cuestae''), and the Takikawa sea cow (''Hydrodamalis spissa''). The fossil genus '' Dusisiren'' is regarded as the sister taxon of ''Hydrodamalis'': together, the two genera form the dugong subfamily Hydrodamalinae. They were the largest member of the order Sirenia, whose only extant members are the dugong (''Dugong dugon'') and the manatees (''Trichechus'' spp.). They reached up to in length, making the Steller's sea cow among the largest mammals other than whales to have existed in the Holocene epoch. Steller's sea cow was first described by Georg Wilhelm Steller, Cuesta by Daryl Domning, and Takikawa by Hitoshi Furusawa. The Steller's sea cow was the only member of the genus to survive into modern times, and, although had formerly been abundant throughout the North Pacific, by the mid 1700s, its range h ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Hydrodamalis Gigas
Steller's sea cow (''Hydrodamalis gigas'') is an extinct sirenian described by Georg Wilhelm Steller in 1741. At that time, it was found only around the Commander Islands in the Bering Sea between Alaska and Russia; its range extended across the North Pacific during the Pleistocene epoch, and likely contracted to such an extreme degree due to the glacial cycle. It is possible that indigenous populations interacted with the animal before Europeans. Steller first encountered it on Vitus Bering's Great Northern Expedition when the crew became shipwrecked on Bering Island. Much of what is known about its behavior comes from Steller's observations on the island, documented in his posthumous publication ''On the Beasts of the Sea''. Within 27 years of its discovery by Europeans, the slow-moving and easily-caught mammal was hunted into extinction for its meat, fat, and hide. Some 18th-century adults would have reached weights of and lengths up to . It was a member of the family Dugo ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Dusisiren
''Dusisiren'' is an extinct genus of dugong related to the Steller's sea cow that lived in the North Pacific during the Neogene. Paleobiology ''Dusisiren'' is a sirenian exemplar of the evolutionary theory of punctuated equilibrium. It evolved from a mangrove-eating ancestor to adapt to cold climates in the North Pacific by developing the capability to feed on kelp beds out on the open coast. The incipient modifications to the cervicals suggest that it was capable of maneuvering and feeding in high-energy environments of surf-swept coasts with deep, cold water.D. P. Domning. 1978. Sirenian evolution in the North Pacific Ocean. University of California Publications in Geological Sciences 118:1-176 Species There are four recognized species of ''Dusisiren'': *''Dusisiren jordani'' (Kellogg, 1925) (type) *''Dusisiren reinharti'' Domning, 1978 *''Dusisiren dewana'' Takahashi, Domning, and Saito, 1986 *''Dusisiren takasatensis'' Kobayashi, Horikawa, & Miyazaki, 1995S. Kobayashi, H. Ho ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Sirenia
The Sirenia (), commonly referred to as sea cows or sirenians, are an order of fully aquatic, herbivorous mammals that inhabit swamps, rivers, estuaries, marine wetlands, and coastal marine waters. The extant Sirenia comprise two distinct families: Dugongidae (the dugong and the now extinct Steller's sea cow) and Trichechidae (manatees, namely the Amazonian manatee, West Indian manatee, and West African manatee) with a total of four species. The Protosirenidae (Eocene sirenians) and Prorastomidae (terrestrial sirenians) families are extinct. Sirenians are classified in the clade Paenungulata, alongside the elephants and the hyraxes, and evolved in the Eocene 50 million years ago (mya). The Dugongidae diverged from the Trichechidae in the late Eocene or early Oligocene (30–35 mya). Sirenians grow to between in length and in weight. The recently extinct Steller's sea cow was the largest known sirenian to have lived, reaching lengths of and weights of . Sirenians have ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Cladistics
Cladistics ( ; from Ancient Greek 'branch') is an approach to Taxonomy (biology), biological classification in which organisms are categorized in groups ("clades") based on hypotheses of most recent common ancestry. The evidence for hypothesized relationships is typically shared derived (phylogenetics), derived characteristics (synapomorphies) that are not present in more distant groups and ancestors. However, from an empirical perspective, common ancestors are inferences based on a cladistic hypothesis of relationships of taxa whose Phenotypic trait, character states can be observed. Theoretically, a last common ancestor and all its descendants constitute a (minimal) clade. Importantly, all descendants stay in their overarching ancestral clade. For example, if the terms ''worms'' or ''fishes'' were used within a ''strict'' cladistic framework, these terms would include humans. Many of these terms are normally used Paraphyly, paraphyletically, outside of cladistics, e.g. as a 'E ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Polymorphism (biology)
In biology, polymorphism is the occurrence of two or more clearly different morphs or forms, also referred to as alternative '' phenotypes'', in the population of a species. To be classified as such, morphs must occupy the same habitat at the same time and belong to a panmictic population (one with random mating). Ford E.B. 1965. ''Genetic polymorphism''. Faber & Faber, London. Put simply, polymorphism is when there are two or more possibilities of a trait on a gene. For example, there is more than one possible trait in terms of a jaguar's skin colouring; they can be light morph or dark morph. Due to having more than one possible variation for this gene, it is termed 'polymorphism'. However, if the jaguar has only one possible trait for that gene, it would be termed "monomorphic". For example, if there was only one possible skin colour that a jaguar could have, it would be termed monomorphic. The term polyphenism can be used to clarify that the different forms arise from the ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Synonym (taxonomy)
In taxonomy, the scientific classification of living organisms, a synonym is an alternative scientific name for the accepted scientific name of a taxon. The Botanical nomenclature, botanical and Zoological nomenclature, zoological codes of nomenclature treat the concept of synonymy differently. * In nomenclature, botanical nomenclature, a synonym is a Binomial nomenclature, scientific name that applies to a taxon that now goes by a different scientific name. For example, Carl Linnaeus, Linnaeus was the first to give a scientific name (under the currently used system of scientific nomenclature) to the Norway spruce, which he called ''Pinus abies''. This name is no longer in use, so it is now a synonym of the current scientific name, ''Picea abies''. * In zoology, moving a species from one genus to another results in a different Binomial nomenclature, binomen, but the name is considered an alternative combination rather than a synonym. The concept of synonymy in zoology is reserved f ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Taxon
In biology, a taxon (back-formation from ''taxonomy''; : taxa) is a group of one or more populations of an organism or organisms seen by taxonomists to form a unit. Although neither is required, a taxon is usually known by a particular name and given a particular ranking, especially if and when it is accepted or becomes established. It is very common, however, for taxonomists to remain at odds over what belongs to a taxon and the criteria used for inclusion, especially in the context of rank-based (" Linnaean") nomenclature (much less so under phylogenetic nomenclature). If a taxon is given a formal scientific name, its use is then governed by one of the nomenclature codes specifying which scientific name is correct for a particular grouping. Initial attempts at classifying and ordering organisms (plants and animals) were presumably set forth in prehistoric times by hunter-gatherers, as suggested by the fairly sophisticated folk taxonomies. Much later, Aristotle, and later st ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
