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Laonastes
The Laotian rock rat or ''kha-nyou'' (''Laonastes aenigmamus'', Lao: ຂະຍຸ), sometimes called the "rat-squirrel", is a species of rodent found in the Khammouan region of Laos. The species was first described in a 2005 article by Paulina Jenkins and coauthors, who considered the animal to be so distinct from all living rodents, they placed it in a new family, Laonastidae. It is in the monotypic genus ''Laonastes''. In 2006, the classification of the Laotian rock rat was disputed by Mary Dawson and coauthors. They suggested the rat belongs to the ancient fossil family Diatomyidae, which was thought to have been extinct for 11 million years, since the late Miocene. It would thereby represent a Lazarus species. The animals resemble large, dark rats with hairy, thick tails like those of a squirrel. Their skulls are very distinctive and have features that separate them from all other living mammals. Classification Upon their initial discovery, Jenkins and coauthors (200 ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Diatomyidae
Diatomyidae is a family of hystricomorph rodents. It is represented by a single living species, ''Laonastes aenigmamus,'' native to Laos in Southeast Asia. Fossil species are known from the Oligocene and Miocene of Asia and eastern Europe. "Lazarus effect" Before ''Laonastes'' was discovered, the family Diatomyidae was known only from fossils. The family has a nearly continuous fossil range from Early Oligocene fossils of '' Fallomus'' from the Lower Chitarwata Formation (32.5 million years ago, Bugti Member, Bugti Hills,) in Balochistan, Pakistan, to Middle/Late Miocene fossils (11 Mya) of ''Diatomys''. Jenkins ''et al.''Jenkins, Paulina D.; Kilpatrick, C. William; Robinson, Mark F. & Timmins, Robert J. (2004): Morphological and molecular investigations of a new family, genus and species of rodent (Mammalia: Rodentia: Hystricognatha) from Lao PDR. ''Systematics and Biodiversity'' 2(4): 419-454. (HTML abstract). Erratum: ''Systematics and Biodiversity'' 3(3):343. reported ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Laonastes Aenigmamus Skull
The Laotian rock rat or ''kha-nyou'' (''Laonastes aenigmamus'', Lao: ຂະຍຸ), sometimes called the "rat-squirrel", is a species of rodent found in the Khammouan region of Laos. The species was first described in a 2005 article by Paulina Jenkins and coauthors, who considered the animal to be so distinct from all living rodents, they placed it in a new family, Laonastidae. It is in the monotypic genus ''Laonastes''. In 2006, the classification of the Laotian rock rat was disputed by Mary Dawson and coauthors. They suggested the rat belongs to the ancient fossil family Diatomyidae, which was thought to have been extinct for 11 million years, since the late Miocene. It would thereby represent a Lazarus species. The animals resemble large, dark rats with hairy, thick tails like those of a squirrel. Their skulls are very distinctive and have features that separate them from all other living mammals. Classification Upon their initial discovery, Jenkins and coauthors (200 ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Lazarus Taxon
In paleontology, a Lazarus taxon (plural ''taxa'') is a taxon that disappears for one or more periods from the fossil record, only to appear again later. Likewise in conservation biology and ecology, it can refer to species or populations that were thought to be extinct, and are rediscovered. The term Lazarus taxon was coined by Karl W. Flessa & David Jablonski in 1983 and was then expanded by Jablonski in 1986. Paul Wignall and Michael Benton defined Lazarus taxa as, "At times of biotic crisis many taxa go extinct, but others only temporarily disappeared from the fossil record, often for intervals measured in millions of years, before reappearing unchanged". Earlier work also supports the concept though without using the name Lazarus taxon, like work by Christopher R. C. Paul. The term refers to the story in the Christian biblical Gospel of John, in which Jesus Christ raised Lazarus from the dead. Potential explanations Lazarus taxa are observational artifacts that app ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Mary Dawson (paleontologist)
Mary R. Dawson (February 27, 1931 – November 29, 2020) was a vertebrate paleontologist and curator emeritus at the Carnegie Museum of Natural History in Pittsburgh, Pennsylvania. Education and career Dawson was raised in Michigan, received her undergraduate degree from Michigan State University, and received her Ph.D. from the University of Kansas. She was Curator of Vertebrate Paleontology at the Carnegie Museum of Natural History in Pittsburgh from 1972 until she retired in 2003, including serving as chair of the Earth Sciences Division from 1973 to 1997. Research Dawson's research has focused on the evolution of mammals, especially of Cenozoic rodents and lagomorphs. She has also maintained an active research program at Ellesmere Island and other sites in the high Arctic which showed that tropical and subtropical animals lived inside the Arctic Circle during the exceptionally warm climates of the Paleogene geological period. Through this work, she and her collaborators ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Miocene
The Miocene ( ) is the first geological epoch of the Neogene Period and extends from about (Ma). The Miocene was named by Scottish geologist Charles Lyell; the name comes from the Greek words (', "less") and (', "new") and means "less recent" because it has 18% fewer modern marine invertebrates than the Pliocene has. The Miocene is preceded by the Oligocene and is followed by the Pliocene. As Earth went from the Oligocene through the Miocene and into the Pliocene, the climate slowly cooled towards a series of ice ages. The Miocene boundaries are not marked by a single distinct global event but consist rather of regionally defined boundaries between the warmer Oligocene and the cooler Pliocene Epoch. During the Early Miocene, the Arabian Peninsula collided with Eurasia, severing the connection between the Mediterranean and Indian Ocean, and allowing a faunal interchange to occur between Eurasia and Africa, including the dispersal of proboscideans into Eurasia. During the ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Chinese River Dolphin
The baiji (; IPA: ; ''Lipotes vexillifer'', ''Lipotes'' meaning "left behind" and ''vexillifer'' "flag bearer") is a possibly extinct species of freshwater dolphin native to the Yangtze river system in China. It is thought to be the first dolphin species driven to extinction due to the impact of humans. This dolphin is listed as “critically endangered: possibly extinct” by the IUCN, has not been seen in 20 years, and several surveys of the Yangtze have failed to find it. In China, the species is also called the Chinese river dolphin, Yangtze river dolphin, Yangtze dolphin and whitefin dolphin. Nicknamed the "Goddess of the Yangtze" (), it was regarded as the goddess of protection by local fishermen and boatmen. It is not to be confused with the Chinese white dolphin (''Sousa chinensis'') or the finless porpoise (''Neophocaena phocaenoides''). The baiji population declined drastically in decades as China industrialized and made heavy use of the river for fishing, transportat ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Saola
The saola (''Pseudoryx nghetinhensis''), also called spindlehorn, Asian unicorn, or infrequently, Vu Quang bovid, is one of the world's rarest large mammals, a forest-dwelling bovine native to the Annamite Range in Vietnam and Laos. It was described in 1993 following a discovery of remains in Vũ Quang National Park by a joint survey of the Vietnamese Ministry of Forestry and the World Wide Fund for Nature. Saolas have since been kept in captivity multiple times, although only for short periods as they died within a matter of weeks to months. The species was first reported in 1992 by Do Tuoc, a forest ecologist, and his associates. The first photograph of a living saola was taken in captivity in 1993. The most recent one was taken in 2013 by a movement-triggered camera in the forest of central Vietnam. It is the only species in genus ''Pseudoryx''. Taxonomy In May 1992, the Ministry of Forestry, Vietnam sent a survey team to examine the biodiversity of the newly established V ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Bumblebee Bat
Kitti's hog-nosed bat (''Craseonycteris thonglongyai''), also known as the bumblebee bat, is a near-threatened species of bat and the only extant member of the family Craseonycteridae. It occurs in western Thailand and southeast Myanmar, where it occupies limestone caves along rivers. Kitti's hog-nosed bat is the smallest species of bat and arguably the world's smallest mammal. It has a reddish-brown or grey coat, with a distinctive pig-like snout. Colonies range greatly in size, with an average of 100 individuals per cave. The bat feeds during short activity periods in the evening and dawn, foraging around nearby forest areas for insects. Females give birth annually to a single offspring. Although the bat's status in Myanmar is not well known, the Thai population is restricted to a single province and may be at risk of extinction. Its potential threats are primarily anthropogenic, and include habitat degradation and the disturbance of roosting sites. Description Kitti's hog-n ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Zagros Mountains Mouse-like Hamster
The Zagros Mountains mouse-like hamster (''Calomyscus bailwardi'') is a relatively little-known rodent which was the first species of mouse-like hamster to be described. The species is distributed throughout much of southern Iran, particularly in the Zagros mountains. It is also known as the Iranian mouse-like hamster, though there are several species of mouse-like hamster found in different parts of Iran. This is the largest species of mouse-like hamster. They are dark grey on top and white underneath. They are found in habitat ranging from barren rocky hillsides to wetter regions. They are known to feed on herbs and grass seed. Graphodatsky et al. (2000) recovered three distinct karyotype A karyotype is the general appearance of the complete set of metaphase chromosomes in the cells of a species or in an individual organism, mainly including their sizes, numbers, and shapes. Karyotyping is the process by which a karyotype is disce ...s from different regions throughout th ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Genus
Genus ( plural genera ) is a taxonomic rank used in the biological classification of extant taxon, living and fossil organisms as well as Virus classification#ICTV classification, viruses. In the hierarchy of biological classification, genus comes above species and below family (taxonomy), family. In binomial nomenclature, the genus name forms the first part of the binomial species name for each species within the genus. :E.g. ''Panthera leo'' (lion) and ''Panthera onca'' (jaguar) are two species within the genus ''Panthera''. ''Panthera'' is a genus within the family Felidae. The composition of a genus is determined by taxonomy (biology), taxonomists. The standards for genus classification are not strictly codified, so different authorities often produce different classifications for genera. There are some general practices used, however, including the idea that a newly defined genus should fulfill these three criteria to be descriptively useful: # monophyly – all descendants ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Goeldi's Marmoset
The Goeldi's marmoset or Goeldi's monkey (''Callimico goeldii'') is a small, South American New World monkey that lives in the upper Amazon basin region of Bolivia, Brazil, Colombia, and Peru. It is the only species classified in the genus ''Callimico'', and the monkeys are sometimes referred to as "callimicos". The species takes its name from its discoverer, Swiss-Brazilian naturalist Emil August Goeldi. Goeldi's marmosets are blackish or blackish-brown in color and the hair on their head and tail sometimes has red, white, or silverly brown highlights. Their bodies are about long, and their tails are about long. They weigh about 0.4835 Kg in captivity and 0.500 Kg in the wild. Their digits have claw like nails except for the hallux, which serve for clinging, scansorial travel, and to extract food from trees. Taxonomy and Evolution Goeldi's marmoset was first described in 1904, making ''Callimico'' one of the more recent monkey genera to be described. In older classifica ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Oligocene
The Oligocene ( ) is a geologic epoch of the Paleogene Period and extends from about 33.9 million to 23 million years before the present ( to ). As with other older geologic periods, the rock beds that define the epoch are well identified but the exact dates of the start and end of the epoch are slightly uncertain. The name Oligocene was coined in 1854 by the German paleontologist Heinrich Ernst Beyrich from his studies of marine beds in Belgium and Germany. The name comes from the Ancient Greek (''olígos'', "few") and (''kainós'', "new"), and refers to the sparsity of extant forms of molluscs. The Oligocene is preceded by the Eocene Epoch and is followed by the Miocene Epoch. The Oligocene is the third and final epoch of the Paleogene Period. The Oligocene is often considered an important time of transition, a link between the archaic world of the tropical Eocene and the more modern ecosystems of the Miocene. Major changes during the Oligocene included a global expansion o ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
