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Kharodacetus Sahnii, Plaster Replica Of Original, IITR-SB 3189
''Kharodacetus'' is a genus of protocetid cetacean from the middle Eocene (late Lutetian, 42 mya) of Kutch, Gujarat, southwestern India. Description ''Kharodacetus'' is a large-sized protocetid with large premolars and a flat supraorbital shield with large orbits (eye sockets). Its snout is long and relatively broad, (though the snout is narrower in '' Gaviacetus'' and ''Makaracetus'', broader in ''Takracetus''), its orbit is high above the palate, and the premolars are large and robust. The molars have a large protocone (unlike ''Babiacetus'') and a large metacone (unlike ''Maiacetus ''Maiacetus'' ("mother whale") is a genus of early middle Eocene (c. 47.5 mya) cetacean from the Habib Rahi Formation of Pakistan. Paleobiology The genus contains a single species, ''Maiacetus inuus'', first described in 2009 on the basis of ...''), and are, relative to P4, longer than in other protocetids. Classification ''Kharodacetus'' was originally described as a species of '' ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Eocene
The Eocene ( ) Epoch is a geological epoch (geology), epoch that lasted from about 56 to 33.9 million years ago (mya). It is the second epoch of the Paleogene Period (geology), Period in the modern Cenozoic Era (geology), Era. The name ''Eocene'' comes from the Ancient Greek (''ēṓs'', "dawn") and (''kainós'', "new") and refers to the "dawn" of modern ('new') fauna that appeared during the epoch. The Eocene spans the time from the end of the Paleocene Epoch to the beginning of the Oligocene Epoch. The start of the Eocene is marked by a brief period in which the concentration of the carbon isotope Carbon-13, 13C in the atmosphere was exceptionally low in comparison with the more common isotope Carbon-12, 12C. The end is set at a major extinction event called the ''Grande Coupure'' (the "Great Break" in continuity) or the Eocene–Oligocene extinction event, which may be related to the impact of one or more large bolides in Popigai impact structure, Siberia and in what is now ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Makaracetus
''Makaracetus'' is an extinct protocetid early whale the remains of which were found in 2004 in Lutetian layers of the Domanda Formation in the Sulaiman Range of Balochistan, Pakistan (, paleocoordinates ). ''Makaracetus'' is unique among archaeocetes in its feeding adaptations; its proboscis and the hypertrophied facial muscles. The generic epithet is a portmanteau of Makara, an elephant-headed sea monster from Hindu mythology, and ''cetus'', Greek for "whale". The species epithet, ''bidens'', is Greek for "two-teeth", in reference to the retention of only two incisors in each premaxilla. ''Makaracetus''' unique features even lead to propose a new classification of Protocidae based on the degree of their aquatic adaptation; with ''Makarcetus'' alone in the subfamily Makaracetinae. A combination of cranial features indicates that ''Makaracetus'' had a short, muscular proboscis similar to a tapir. There are broad and shallow narial grooves on the dorsal side of the premax ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Prehistoric Cetacean Genera
Prehistory, also known as pre-literary history, is the period of human history between the use of the first stone tools by hominins 3.3 million years ago and the beginning of recorded history with the invention of writing systems. The use of symbols, marks, and images appears very early among humans, but the earliest known writing systems appeared 5000 years ago. It took thousands of years for writing systems to be widely adopted, with writing spreading to almost all cultures by the 19th century. The end of prehistory therefore came at very different times in different places, and the term is less often used in discussing societies where prehistory ended relatively recently. In the early Bronze Age, Sumer in Mesopotamia, the Indus Valley Civilisation, and ancient Egypt were the first civilizations to develop their own scripts and to keep historical records, with their neighbors following. Most other civilizations reached the end of prehistory during the following Iron Age. T ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Fossil Taxa Described In 2014
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] |
Protocetidae
Protocetidae, the protocetids, form a diverse and heterogeneous group of extinct cetaceans known from Asia, Europe, Africa, South America, and North America. Description There were many genera, and some of these are very well known (e.g., ''Rodhocetus''). Known protocetids had large fore- and hindlimbs that could support the body on land, and it is likely that they lived amphibiously: in the sea and on land. It is unclear at present whether protocetids had flukes (the horizontal tail fin of modern cetaceans). However, what is clear is that they are adapted even further to an aquatic life-style. In ''Rodhocetus'', for example, the sacrum – a bone that in land-mammals is a fusion of five vertebrae that connects the pelvis with the rest of the vertebral column – was divided into loose vertebrae. However, the pelvis retain a sacroiliac joint. Furthermore, the nasal openings are now halfway up the snout; a first step towards the telescoped condition in modern whales. ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Maiacetus
''Maiacetus'' ("mother whale") is a genus of early middle Eocene (c. 47.5 mya) cetacean from the Habib Rahi Formation of Pakistan. Paleobiology The genus contains a single species, ''Maiacetus inuus'', first described in 2009 on the basis of two specimens, including a specimen which has been interpreted as a pregnant female and its fetus. This represents the first description of a fetal skeleton of an archaeocete. The position of the fetus (head-first) suggests that the animal gave birth on land."Earliest whales gave birth on land" '''', 3 February 2009 Modern whales generally give birth tail first, while land mammals give birth head first. ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Babiacetus
''Babiacetus'' is an extinct genus of early cetacean that lived during the late Lutetian middle Eocene of India ().. Retrieved April 2013. It was named after its type locality, the Harudi Formation in the Babia Hills (: paleocoordinates ), Kutch District, Gujarat, India. ''Babiacetus'' was named by in an abstract based on the specimen's type (GSI 19647, left and right dentaries with cheek teeth). Gingerich and colleagues found a skull (GSP-UM 3005, much of a skull and lower jaws) while collecting a skeleton of a new species of Protosiren (''Protosiren sattaensis'') in the Drazinda Formation (, paleocoordinates ) in the Sulaiman Range of Punjab, Pakistan. described both the original find and their new specimen. described '' B. mishrai'' from the specimen (RUSB 2512, a partial skull) collected in the Harudi Formation.. Retrieved March 2013. ''Babiacetus'' is one of the larger protocetids. Its hydrodynamic skull and pointed, anteroposteriorly (front-back) oriented incisor ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Protocone
A cusp is a pointed, projecting, or elevated feature. In animals, it is usually used to refer to raised points on the crowns of teeth. The concept is also used with regard to the leaflets of the four heart valves. The mitral valve, which has two cusps, is also known as the bicuspid valve, and the tricuspid valve has three cusps. In humans A cusp is an occlusal or incisal eminence on a tooth. Canine teeth, otherwise known as cuspids, each possess a single cusp, while premolars, otherwise known as bicuspids, possess two each. Molars normally possess either four or five cusps. In certain populations the maxillary molars, especially first molars, will possess a fifth cusp situated on the mesiolingual cusp known as the Cusp of Carabelli. Buccal Cusp- One other variation of the upper first premolar is the 'Uto-Aztecan' upper premolar. It is a bulge on the buccal cusp that is only found in Native American Indians, with highest frequencies of occurrence in Arizona. The name is no ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Premolars
The premolars, also called premolar teeth, or bicuspids, are transitional teeth located between the canine and molar teeth. In humans, there are two premolars per quadrant in the permanent set of teeth, making eight premolars total in the mouth. They have at least two cusps. Premolars can be considered transitional teeth during chewing, or mastication. They have properties of both the canines, that lie anterior and molars that lie posterior, and so food can be transferred from the canines to the premolars and finally to the molars for grinding, instead of directly from the canines to the molars. Human anatomy The premolars in humans are the maxillary first premolar, maxillary second premolar, mandibular first premolar, and the mandibular second premolar. Premolar teeth by definition are permanent teeth distal to the canines, preceded by deciduous molars. Morphology There is always one large buccal cusp, especially so in the mandibular first premolar. The lower second p ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Takracetus
''Takracetus'' was a primitive cetacean that lived approximately . The type specimen (GSP-UM 3041) is a partial skull though the literature mentions a second more complete specimen. Notes References * * Protocetidae Prehistoric cetacean genera Fossil taxa described in 1995 Extinct mammals of Asia {{paleo-whale-stub ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Gaviacetus
''Gaviacetus'' (from Latin ''Gavia'', "loon" and ''cetus'', "whale") is an extinct archaeocete whale that lived approximately . ''Gaviacetus'' was named for its characteristic narrow rostrum and the fast pursuit predation suggested by its unfused sacral vertebrae. Location The only known ''Gaviacetus razai'' specimen was found in Punjab, Pakistan. (, paleocoordinates ) Description The skull of ''Gaviacetus'' is characteristic of protocetids, but the rostrum is extremely narrow anterior to P3, suggesting some kind of trophic specialization. The well-preserved auditory bulla in 's specimen is dense like in other archaeocetes, is equipped with a prominent sigmoid process, but has 3-5 contacts with the rest of the cranium. Preserved alveoli (tooth sockets) show that ''Gaviacetus'' had double- and triple-rooted cheek teeth, but some controversy remains regarding the number of molars. Based on other cranial characters, concluded that ''Gaviacetus'' is a protocetid (more primitive ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Hans Thewissen
Hans Thewissen is a Dutch-American paleontologist. His field work has discovered fossils for the steps in the transition from land to water in whales: '' Ambulocetus'', '' Pakicetus'', ''Indohyus'' and '' Kutchicetus''. He now studies modern bowhead and beluga whales in Alaska to learn about their biology and their implications for management and conservation. Early life Thewissen has always been interested in paleontology and natural history. His mother said that when Thewissen was a small boy, she had to sort through his pockets before laundry time to take out the rocks and worms he collected. His father used to take him to the town of Maastricht, and they collected fossils from the Maastrichtian period. 12th birthday present was a rock hammer, which has accompanied him on all collecting trips since. He grew up just 2 miles from Liessel, a fossil locale that yielded the first whales he ever collected. Educational background After finishing Gymnasium secondary education in ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
