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2018 In Reptile Paleontology
Lizards and snakes Research * Triassic reptile ''Megachirella wachtleri'' is reinterpreted as the oldest known Crown group#Stem groups, stem-Squamata, squamate by Simões ''et al.'' (2018). * Simões ''et al.'' (2018) perform X-ray scans at the Micrometre, micron scale of the holotype specimen of ''Megachirella wachtleri''. * Fossil trackways probably made by lizards running Bipedalism, bipedally are described from the Lower Cretaceous (Aptian-early Albian) Hasandong Formation (South Korea) by Lee ''et al.'' (2018), who name a new ichnotaxon ''Sauripes hadongensis''. * New fossil material of ''Dicothodon bajaensis'', providing new information on the tooth replacement pattern in this species, is described from the Campanian of Mexico by Chavarría-Arellano, Simões & Montellano-Ballesteros (2018). * A study on the Manus (anatomy), manus of a putative Crown group#Stem groups, stem-gekkotan from the Cretaceous amber from Myanmar is published by Fontanarrosa, Daza & Abdala (2018), w ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Mexico
Mexico ( Spanish: México), officially the United Mexican States, is a country in the southern portion of North America. It is bordered to the north by the United States; to the south and west by the Pacific Ocean; to the southeast by Guatemala, Belize, and the Caribbean Sea; and to the east by the Gulf of Mexico. Mexico covers ,Mexico '' The World Factbook''. . making it the world's 13th-largest country by area; with approximately 12 ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Dominican Amber
Dominican amber is amber from the Dominican Republic derived from resin of the extinct tree ''Hymenaea protera''. Dominican amber differentiates itself from Baltic amber by being nearly always transparent, and it has a higher number of fossil inclusions. This has enabled the detailed reconstruction of the ecosystem of a long-vanished tropical forest.George Poinar, Jr. and Roberta Poinar, 1999. ''The Amber Forest: A Reconstruction of a Vanished World'', (Princeton University Press) Age A study in the early 1990s returned a date up to 40 million years old. However, according to Poinar, Dominican amber dates from Oligocene to Miocene, thus about 25 million years old. The oldest, and hardest of this amber comes from the mountain region north of Santiago. The ''La Cumbre'', ''La Toca'', ''Palo Quemado'', ''La Bucara'', and ''Los Cacaos'' mining sites in the ''Cordillera Septentrional'' not far from Santiago. Amber has also been found in the south-eastern Bayaguana/Sabana de la Mar a ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Sphaerodactylus
''Sphaerodactylus'' is a genus of geckos from the Americas that are distinguished from other Gekkota by their small size, by their round, rather than vertical, eye pupils, and by each digit terminating in a single, round adhesive pad or scale, from which their name (''Sphaero'' = round, ''dactylus'' = finger) is derived. All species in this genus are rather small, but two species, '' S. ariasae'' and '' S. parthenopion'', are tiny, and – with a snout-vent length of about – the smallest reptiles in the world. Fossil record Fossil remains referred to ''Sphaerodactylus'' have been recovered from Dominican amber. Species The following 108 species are recognized as being valid. *''Sphaerodactylus alphus'' - Guanaja large-scaled geckolet *'' Sphaerodactylus altavelensis'' - Alto Velo least gecko, Alto Velo sphaero *''Sphaerodactylus argivus'' - Cayman least gecko *'' Sphaerodactylus argus'' - ocellated gecko, ocellated sphaero, stippled sphaero *''Sphaerodactylus ariasae' ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Museum Koenig
The Alexander Koenig Zoological Research Museum (German: ''Zoologisches Forschungsmuseum Alexander Koenig'', abbreviated ZFMK) is a natural history museum and zoological research institution in Bonn, Germany. The museum is named after Alexander Koenig, who donated his collection of specimens to the institution. The museum was opened in 1934 and is affiliated with the Leibniz Association. On 1 September 1948 the museum saw the opening of the Parlamentarischer Rat, the organ to create the German constitution. The actual proceedings happened in the nearby Pädagogische Akademie, the later Bundeshaus. History The museum was founded by the private scholar Alexander Koenig (1858–1940) as a private institute for zoological research and public education. Alexander Koenig, who was born in 1858 as the son of the wealthy merchant Leopold Koenig, began to collect birds and mammals as a boy. He later studied zoology and received a doctorate in natural history in 1884. In the following y ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Paleogene
The Paleogene ( ; also spelled Palaeogene or Palæogene; informally Lower Tertiary or Early Tertiary) is a geologic period and system that spans 43 million years from the end of the Cretaceous Period million years ago (Mya) to the beginning of the Neogene Period Mya. It is the beginning of the Cenozoic Era of the present Phanerozoic Eon. The earlier term Tertiary Period was used to define the span of time now covered by the Paleogene Period and subsequent Neogene Period; despite no longer being recognised as a formal stratigraphic term, 'Tertiary' is still widely found in earth science literature and remains in informal use. Paleogene is often abbreviated "Pg" (but the United States Geological Survey uses the abbreviation PE for the Paleogene on the Survey's geologic maps). During the Paleogene, mammals diversified from relatively small, simple forms into a large group of diverse animals in the wake of the Cretaceous–Paleogene extinction event that ended the preceding C ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Tanzania
Tanzania (; ), officially the United Republic of Tanzania ( sw, Jamhuri ya Muungano wa Tanzania), is a country in East Africa within the African Great Lakes region. It borders Uganda to the north; Kenya to the northeast; Comoro Islands and the Indian Ocean to the east; Mozambique and Malawi to the south; Zambia to the southwest; and Rwanda, Burundi, and the Democratic Republic of the Congo to the west. Mount Kilimanjaro, Africa's highest mountain, is in northeastern Tanzania. According to the United Nations, Tanzania has a population of million, making it the most populous country located entirely south of the equator. Many important hominid fossils have been found in Tanzania, such as 6-million-year-old Pliocene hominid fossils. The genus Australopithecus ranged across Africa between 4 and 2 million years ago, and the oldest remains of the genus '' Homo'' are found near Lake Olduvai. Following the rise of ''Homo erectus'' 1.8 million years ago, humanity sprea ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Nsungwe Formation
The Nsungwe Formation is a formation in the Rukwa Rift Basin of the East African Rift System, it is Oligocene in age based on U-Pb dating of a tuff horizon within the formation. It is part of the Red Sandstone Group along with the uncomfortably underlying Mid-Cretaceous Galula Formation It is divided into two members, the lower Utengule Member, and the upper Songwe member. It is notable for being one of the most important Paleogene fossil deposits in Sub-Saharan Africa. Geology The lithology of the two members are quite different, representing different fluvial environments. The Utengule member is 85 m thick and predominantly consists of red-orange sandstones and matrix to clast supported conglomerates. The overlying Songwe Member is approximately twice as thick as the Utengule member, being 310–320 m thick in the type section. It is much finer grained, consisting of red-orange and grey green claystones, siltstones, mudstones, lenticular sandstones and tuffs. The sediments of ... [...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 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" ... Epoch. The Oligocene is the third and final epoch of ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Maxilla
The maxilla (plural: ''maxillae'' ) in vertebrates is the upper fixed (not fixed in Neopterygii) bone of the jaw formed from the fusion of two maxillary bones. In humans, the upper jaw includes the hard palate in the front of the mouth. The two maxillary bones are fused at the intermaxillary suture, forming the anterior nasal spine. This is similar to the mandible (lower jaw), which is also a fusion of two mandibular bones at the mandibular symphysis. The mandible is the movable part of the jaw. Structure In humans, the maxilla consists of: * The body of the maxilla * Four processes ** the zygomatic process ** the frontal process of maxilla ** the alveolar process ** the palatine process * three surfaces – anterior, posterior, medial * the Infraorbital foramen * the maxillary sinus * the incisive foramen Articulations Each maxilla articulates with nine bones: * two of the cranium: the frontal and ethmoid * seven of the face: the nasal, zygomatic, lacrimal, ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Adhesion
Adhesion is the tendency of dissimilar particles or surfaces to cling to one another ( cohesion refers to the tendency of similar or identical particles/surfaces to cling to one another). The forces that cause adhesion and cohesion can be divided into several types. The intermolecular forces responsible for the function of various kinds of stickers and sticky tape fall into the categories of chemical adhesion, dispersive adhesion, and diffusive adhesion. In addition to the cumulative magnitudes of these intermolecular forces, there are also certain emergent mechanical effects. Surface energy Surface energy is conventionally defined as the work that is required to build an area of a particular surface. Another way to view the surface energy is to relate it to the work required to cleave a bulk sample, creating two surfaces. If the new surfaces are identical, the surface energy γ of each surface is equal to half the work of cleavage, W: γ = (1/2)W11. If the surf ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Myanmar
Myanmar, ; UK pronunciations: US pronunciations incl. . Note: Wikipedia's IPA conventions require indicating /r/ even in British English although only some British English speakers pronounce r at the end of syllables. As John Wells explains, the English spellings of both Myanmar and Burma assume a non-rhotic variety of English, in which the letter r before a consonant or finally serves merely to indicate a long vowel: �mjænmɑː, ˈbɜːmə So the pronunciation of the last syllable of Myanmar as ɑːror of Burma as ɜːrməby some speakers in the UK and most speakers in North America is in fact a spelling pronunciation based on a misunderstanding of non-rhotic spelling conventions. The final ''r'' in ''Myanmar'' was not intended for pronunciation and is there to ensure that the final a is pronounced with the broad ''ah'' () in "father". If the Burmese name my, မြန်မာ, label=none were spelled "Myanma" in English, this would be pronounced at the end by al ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
