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Juramaia
''Juramaia'' is an extinct genus of very basal eutherian mammal known from the Late Jurassic ( Oxfordian stage) deposits of western Liaoning, China. It is a small shrew-like mammal with a body length of approximately 70–100 mm, making it similar in size to the modern De Winton's shrew. ''Juramaia'' is known from the holotype BMNH PM1343, an articulated and nearly complete skeleton including incomplete skull preserved with full dentition. Discovery It was collected in the Daxigou site, Jianchang, from the Tiaojishan Formation dated at about . It was first named by Zhe-Xi Luo, Chong-Xi Yuan, Qing-Jin Meng and Qiang Ji in 2011 and the type species is ''Juramaia sinensis''. Evolution The discovery of ''Juramaia'' provides new insight into the evolution of placental mammals by showing that their lineage diverged from that of the marsupials 35 million years earlier than previously thought. Furthermore, its discovery fills gaps in the fossil record and helps to calibrate mod ... [...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] |
Tiaojishan Formation
The Tiaojishan Formation is a geological formation in Hebei and Liaoning, People's Republic of China, dating to the middle-late Jurassic period (Bathonian- Oxfordian stages). It is known for its exceptionally preserved fossils, including those of plants, insects and vertebrates. It is made up mainly of pyroclastic rock interspersed with basic volcanic and sedimentary rocks. Previously, the Tiaojishan Formation was grouped together with the underlying Haifanggou Formation (also known as the Jiulongshan Formation) as a single "Lanqi Formation." The Tiaojishan Formation forms a key part of the Yanliao Biota assemblage, alongside the Haifanggou Formation. Age Using Argon–argon dating, Wang and colleagues in 2005 dated part of the Tiaojishan Formation to about 160 million years ago, the beginning of the Oxfordian stage, the first stage of the Upper Jurassic epoch. In 2006, a study by Liu and colleagues used U-Pb zircon dating to conclude that the Tiaojishan Formation correlates wi ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Eomaia Scansoria
''Eomaia'' ("dawn mother") is a genus of extinct fossil mammals containing the single species ''Eomaia scansoria'', discovered in rocks that were found in the Yixian Formation, Liaoning Province, China, and dated to the Barremian Age of the Lower Cretaceous about . The single fossil specimen of this species is in length and virtually complete. An estimate of the body weight is between . It is exceptionally well-preserved for a 125-million-year-old specimen. Although the fossil's skull is squashed flat, its teeth, tiny foot bones, cartilages and even its fur are visible. Description The ''Eomaia'' fossil shows clear traces of hair. However, this is not the earliest clear evidence of hair in the mammalian lineage, as fossils of ''Volaticotherium'', and the docodont ''Castorocauda'', discovered in rocks dated to about , also have traces of fur. ''Eomaia scansoria'' possessed several features in common with placental mammals that distinguish them from metatherians, the group that i ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Eomaia
''Eomaia'' ("dawn mother") is a genus of extinct fossil mammals containing the single species ''Eomaia scansoria'', discovered in rocks that were found in the Yixian Formation, Liaoning Province, China, and dated to the Barremian Age of the Lower Cretaceous about . The single fossil specimen of this species is in length and virtually complete. An estimate of the body weight is between . It is exceptionally well-preserved for a 125-million-year-old specimen. Although the fossil's skull is squashed flat, its teeth, tiny foot bones, cartilages and even its fur are visible. Description The ''Eomaia'' fossil shows clear traces of hair. However, this is not the earliest clear evidence of hair in the mammalian lineage, as fossils of ''Volaticotherium'', and the docodont ''Castorocauda'', discovered in rocks dated to about , also have traces of fur. ''Eomaia scansoria'' possessed several features in common with placental mammals that distinguish them from metatherians, the group that i ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Montanalestes
''Montanalestes'' is an extinct mammal known from the Cretaceous in North America. Classification Known from only six fossil teeth, ''Montanalestes'' is an example of the less well-preserved early eutherian 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 tra ...s found on the northern hemisphere, apparently more closely related to later eutherians than '' Prokennalestes'', and '' Murtoilestes''. References Prehistoric eutherians Cretaceous mammals of North America Cloverly fauna Fossil taxa described in 1999 Prehistoric mammal genera {{cretaceous-mammal-stub ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Sinodelphys Szalayi
''Sinodelphys'' is an extinct eutherian from the Early Cretaceous, estimated to be 125 million years old. It was discovered and described in 2003 in rocks of the Yixian Formation in Liaoning Province, China, by a team of scientists including Zhe-Xi Luo and John Wible. Fossil record Only one fossil specimen is known, a slab and counterslab given catalog number CAGS00-IG03. It is in the collection of the Chinese Academy of Geological Sciences. ''Sinodelphys szalayi'' grew only 15 cm (5.9 in) long and possibly weighed about 30 g (1.05 oz). Its fossilized skeleton is surrounded by impressions of fur and soft tissue, thanks to the exceptional sediment that preserves such details. Luo et al. (2003) inferred from the foot structure of ''Sinodelphys'' that it was a scansorial tree-dweller, like its non-marsupial contemporary ''Eomaia'' and modern opossums such as ''Didelphis''. ''Sinodelphys'' probably hunted worms and insects. Most Mesozoic metatherians have been found ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Late Jurassic
The Late Jurassic is the third epoch of the Jurassic Period, and it spans the geologic time from 163.5 ± 1.0 to 145.0 ± 0.8 million years ago (Ma), which is preserved in Upper Jurassic strata.Owen 1987. In European lithostratigraphy, the name "Malm" indicates rocks of Late Jurassic age. In the past, ''Malm'' was also used to indicate the unit of geological time, but this usage is now discouraged to make a clear distinction between lithostratigraphic and geochronologic/chronostratigraphic units. Subdivisions The Late Jurassic is divided into three ages, which correspond with the three (faunal) stages of Upper Jurassic rock: Paleogeography During the Late Jurassic Epoch, Pangaea broke up into two supercontinents, Laurasia to the north, and Gondwana to the south. The result of this break-up was the spawning of the Atlantic Ocean. However, at this time, the Atlantic Ocean was relatively narrow. Life forms of the epoch This epoch is well known for many famous types of dinosau ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Skull
The skull is a bone protective cavity for the brain. The skull is composed of four types of bone i.e., cranial bones, facial bones, ear ossicles and hyoid bone. However two parts are more prominent: the cranium and the mandible. In humans, these two parts are the neurocranium and the viscerocranium ( facial skeleton) that includes the mandible as its largest bone. The skull forms the anterior-most portion of the skeleton and is a product of cephalisation—housing the brain, and several sensory structures such as the eyes, ears, nose, and mouth. In humans these sensory structures are part of the facial skeleton. Functions of the skull include protection of the brain, fixing the distance between the eyes to allow stereoscopic vision, and fixing the position of the ears to enable sound localisation of the direction and distance of sounds. In some animals, such as horned ungulates (mammals with hooves), the skull also has a defensive function by providing the mount (on the front ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Fossil Taxa Described In 2011
A fossil (from Classical Latin , ) is any preserved remains, impression, or trace of any once-living thing from a past geological age. Examples include bones, shells, exoskeletons, stone imprints of animals or microbes, objects preserved in amber, hair, petrified wood and DNA remnants. The totality of fossils is known as the ''fossil record''. Paleontology is the study of fossils: their age, method of formation, and evolutionary significance. Specimens are usually considered to be fossils if they are over 10,000 years old. The oldest fossils are around 3.48 billion years old to 4.1 billion years old. Early edition, published online before print. The observation in the 19th century that certain fossils were associated with certain rock strata led to the recognition of a geological timescale and the relative ages of different fossils. The development of radiometric dating techniques in the early 20th century allowed scientists to quantitatively measure the absolute ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Late Jurassic Mammals Of Asia
Late may refer to: * LATE, an acronym which could stand for: ** 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 Music * ''Late'' (album), a 2000 album by The 77s * Late!, a pseudonym used by Dave Grohl on his ''Pocketwatch'' album * Late (rapper), an underground rapper from Wolverhampton * "Late" (song), a song by Blue Angel * "Late", a song by Kanye West from ''Late Registration'' Other * Late (Tonga), an uninhabited volcanic island southwest of Vavau in the kingdom of Tonga * "Late" (''The Handmaid's Tale''), a television episode * LaTe, Oy Laivateollisuus Ab, a defunct shipbuilding company * Late may refer to a person who is Dead See also * * * ''Lates'', a genus of fish in the lates perch family * Later (other) * Tardiness * Tardiness (scheduling) In scheduling, tardiness is a measure of a delay in exe ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
