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Siamoperadectes
''Siamoperadectes'' is a genus of non-marsupial metatherian from the Miocene of Thailand. A member of Peradectidae, it is the first member of its clade known from South Asia, and among the last non-marsupial metatherians. Description The type specimen of ''Siamoperadectes'' is a single third upper molar found in the Li Mae Long Basin, northern Thailand. It displays a rectilinear predilambdodont centrocrista, lacks an hypocone and has a moderately slender lingual part of the molar, all characteristics that most closely connect it to peradectid metatherians. However, it also displays several unique characteristics: - a deep and narrow protofossa; - very weak conules; - an anteroposteriorly compressed protocone; - a posterior cingulum at the base of the metacone. The molar is quite small, and in life would probably have belonged to a creature about the size of a modern ''Monodelphis'' opossum. Though peradectids have been traditionally considered scansorial, the fact that t ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Li Mae Long
The Mae Long Formation in the Li Basin (also referred to as Li Mae Long) is a fossil site in Lamphun Province, Thailand. The fossils found are thought to date to the late Early Miocene, about 18 million years ago, corresponding to the European zone MN 4.Mein and Ginsburg, 1997, p. 783 Fossil content Mammals found at the site include: ;Metatherians * '' Siamoperadectes minutus'' ; Lipotyphlans * ''Hylomys engesseri'' * ''Neotetracus butleri'' * '' Thaiagymnura equilateralis'' * Unidentified Erinaceidae, possibly '' Mioechinus'' * '' Scapanulus lampounensis'' ;Bats * Unidentified species possibly belonging to '' Taphozous'' * Unidentified species of ''Megaderma'' * '' Hipposideros felix'' * '' H. khengkao'' * '' Rhinolophus yongyuthsi'' * Unidentified species of Rhinolophoidea * ''Ia lanna'' * '' Rhizomops mengraii'' * Unidentified species of Vespertilionidae ;Treeshrews * '' Tupaia miocenica'' ;Primates * ?''Nycticebus linglom'' * '' Tarsius thailandica'' ;Rodents * '' Ratufa m ... [...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] |
Metatheria
Metatheria is a mammalian clade that includes all mammals more closely related to marsupials than to placentals. First proposed by Thomas Henry Huxley in 1880, it is a more inclusive group than the marsupials; it contains all marsupials as well as many extinct non-marsupial relatives. There are three extant subclasses of mammals, one being metatherians: #monotremes: egg laying mammals like the platypus and the echidna, #metatheria: marsupials, which includes three American orders ( Didelphimorphia, Paucituberculata and Microbiotheria) and four Australasian orders (Notoryctemorphia, Dasyuromorphia, Peramelemorphia and Diprotodontia), and the # eutherians: placental mammals, consisting of four superorders divided into 21 orders. Metatherians belong to a subgroup of the northern tribosphenic mammal clade or Boreosphenida. They differ from all other mammals in certain morphologies like their dental formula, which includes about five upper and four lower incisors, a canine, three pre ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Tupaia Miocenica
''Tupaia miocenica'' is a fossil treeshrew from the Miocene of Thailand. Known only from a single tooth, an upper first or second molar, it is among the few known fossil treeshrews. With a length of 3.57 mm, the tooth is large for a treeshrew. At the back lingual corner (the side of the tongue), the tooth shows a small cusp, the hypocone, that is separated from the protocone in front of it by a narrow valley. The condition of the hypocone distinguishes this species from various other treeshrews. In addition, the presence of a well-developed but simple mesostyle (a small cuspule) is distinctive. Taxonomy ''Tupaia miocenica'' was described in 1997 by French paleontologists Pierre Mein and Léonard Ginsburg in a report on the fossil mammals of Li Mae Long, a Miocene site in Thailand.Mein and Ginsburg, 1997, p. 804 The animal is known from a single tooth, which according to Mein and Ginsburg's comparisons most closely resembles the living treeshrews of the genus '' Tupaia''.Me ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Metatheria
Metatheria is a mammalian clade that includes all mammals more closely related to marsupials than to placentals. First proposed by Thomas Henry Huxley in 1880, it is a more inclusive group than the marsupials; it contains all marsupials as well as many extinct non-marsupial relatives. There are three extant subclasses of mammals, one being metatherians: #monotremes: egg laying mammals like the platypus and the echidna, #metatheria: marsupials, which includes three American orders ( Didelphimorphia, Paucituberculata and Microbiotheria) and four Australasian orders (Notoryctemorphia, Dasyuromorphia, Peramelemorphia and Diprotodontia), and the # eutherians: placental mammals, consisting of four superorders divided into 21 orders. Metatherians belong to a subgroup of the northern tribosphenic mammal clade or Boreosphenida. They differ from all other mammals in certain morphologies like their dental formula, which includes about five upper and four lower incisors, a canine, three pre ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Eutheria
Eutheria (; from Greek , 'good, right' and , 'beast'; ) is the clade consisting of all therian mammals that are more closely related to placentals than to marsupials. Eutherians are distinguished from noneutherians by various phenotypic traits of the feet, ankles, jaws and teeth. All extant eutherians lack epipubic bones, which are present in all other living mammals (marsupials and monotremes). This allows for expansion of the abdomen during pregnancy. The oldest-known eutherian species is '' Juramaia sinensis'', dated at from the early Late Jurassic ( Oxfordian) of China. Eutheria was named in 1872 by Theodore Gill; in 1880 Thomas Henry Huxley defined it to encompass a more broadly defined group than Placentalia. Characteristics Distinguishing features are: *an enlarged malleolus ("little hammer") at the bottom of the tibia, the larger of the two shin bones *the joint between the first metatarsal bone and the entocuneiform bone (the innermost of the three cuneiform ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Placental
Placental mammals (infraclass Placentalia ) are one of the three extant subdivisions of the class Mammalia, the other two being Monotremata and Marsupial Marsupials are any members of the mammalian infraclass Marsupialia. All extant marsupials are endemic to Australasia, Wallacea and the Americas. A distinctive characteristic common to most of these species is that the young are carried in a po ...ia. Placentalia contains the vast majority of extant mammals, which are partly distinguished from monotremes and marsupials in that the fetus (biology), fetus is carried in the uterus of its mother to a relatively late stage of development. The name is something of a misnomer considering that marsupials also nourish their fetuses via a placenta, though for a relatively briefer period, giving birth to less developed young which are then nurtured for a period inside the mother's pouch (marsupial), pouch. Anatomical features Placental mammals are anatomically distinguished from othe ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Sparassodonta
Sparassodonta (from Ancient Greek, Greek ['], to tear, rend; and , gen. [', '], tooth) is an extinct order (biology), order of carnivore, carnivorous metatherian mammals native to South America, related to modern marsupials. They were once considered to be true marsupials, but are now thought to be a separate side branch that split before the last common ancestor of all modern marsupials. A number of these mammalian predators closely resemble placental predators that evolved separately on other continents, and are cited frequently as examples of convergent evolution. They were first described by Florentino Ameghino, from fossils found in the Santa Cruz beds of Patagonia. Sparassodonts were present throughout South America's long period of "splendid isolation" during the Cenozoic; during this time, they shared the niches for large warm-blooded predators with the flightless Phorusrhacidae, terror birds. Previously, it was thought that these mammals died out in the face of competit ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Late Cretaceous
The Late Cretaceous (100.5–66 Ma) is the younger of two epochs into which the Cretaceous Period is divided in the geologic time scale. Rock strata from this epoch form the Upper Cretaceous Series. The Cretaceous is named after ''creta'', the Latin word for the white limestone known as chalk. The chalk of northern France and the white cliffs of south-eastern England date from the Cretaceous Period. Climate During the Late Cretaceous, the climate was warmer than present, although throughout the period a cooling trend is evident. The tropics became restricted to equatorial regions and northern latitudes experienced markedly more seasonal climatic conditions. Geography Due to plate tectonics, the Americas were gradually moving westward, causing the Atlantic Ocean to expand. The Western Interior Seaway divided North America into eastern and western halves; Appalachia and Laramidia. India maintained a northward course towards Asia. In the Southern Hemisphere, Australia and Ant ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Diatomys Liensis
''Diatomys'' is an extinct rodent genus known from Miocene deposits in China, Japan, Pakistan, and Thailand. The fossil range is from the late Early Miocene to the Middle Miocene (22.5–11 Ma). Specimens Specifically the strata and regions from which ''Diatomys'' has been collected are: Shanwang series in Shandong province, China, Jiangsu province in China, Kyūshū in Japan, the Siwaliks in northern Pakistan, and Li Basin in Lamphun Province, Thailand. Li (1974) described ''Diatomys shantungensis'' on the basis of two moderately complete specimens from Shandong. This material had good preservation of dental characters, but much of the skull was difficult to interpret due to flattening. Dawson ''et al.'' (2006) reported the finding of another ''D. shantungensis'' fossil from Shandong that showed much improved preservation of cranial and skeletal characters. Impressions of hair and whiskers were observable in the specimen. Mein and Ginsburg (1985) described ''Diatomys lien ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
South America
South America is a continent entirely in the Western Hemisphere and mostly in the Southern Hemisphere, with a relatively small portion in the Northern Hemisphere at the northern tip of the continent. It can also be described as the southern subregion of a single continent called America. South America is bordered on the west by the Pacific Ocean and on the north and east by the Atlantic Ocean; North America and the Caribbean Sea lie to the northwest. The continent generally includes twelve sovereign states: Argentina, Bolivia, Brazil, Chile, Colombia, Ecuador, Guyana, Paraguay, Peru, Suriname, Uruguay, and Venezuela; two dependent territories: the Falkland Islands and South Georgia and the South Sandwich Islands; and one internal territory: French Guiana. In addition, the ABC islands of the Kingdom of the Netherlands, Ascension Island (dependency of Saint Helena, Ascension and Tristan da Cunha, a British Overseas Territory), Bouvet Island ( dependency of Norway), Pa ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Rodents
Rodents (from Latin , 'to gnaw') are mammals of the order Rodentia (), which are characterized by a single pair of continuously growing incisors in each of the upper and lower jaws. About 40% of all mammal species are rodents. They are native to all major land masses except for New Zealand, Antarctica, and several oceanic islands, though they have subsequently been introduced to most of these land masses by human activity. Rodents are extremely diverse in their ecology and lifestyles and can be found in almost every terrestrial habitat, including human-made environments. Species can be arboreal, fossorial (burrowing), saltatorial/richochetal (leaping on their hind legs), or semiaquatic. However, all rodents share several morphological features, including having only a single upper and lower pair of ever-growing incisors. Well-known rodents include mice, rats, squirrels, prairie dogs, porcupines, beavers, guinea pigs, and hamsters. Rabbits, hares, and pikas, whose incisors ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
