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Piscobalaena
''Piscobalaena'' is an extinct genus of cetaceans, which lived from the Middle to Late Miocene epochs (about 11.6 to 5.3 million years ago) in Peru and Florida.''Piscobalaena'' at .org Its fossils have been found in the of and the of Florida. At least some in ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Piscobalaena Nana Plio Inf
''Piscobalaena'' is an extinct genus of cetaceans, which lived from the Middle to Late Miocene epochs (about 11.6 to 5.3 million years ago) in Peru and Florida.''Piscobalaena'' at .org Its fossils have been found in the of and the of Florida. At least some in ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Megalodon
Megalodon (''Otodus megalodon''), meaning "big tooth", is an extinct species of mackerel shark that lived approximately 23 to 3.6 million years ago (Mya), from the Early Miocene to the Pliocene epochs. It was formerly thought to be a member of the family Lamnidae and a close relative of the great white shark (''Carcharodon carcharias''). However, it is now classified into the extinct family Otodontidae, which diverged from the great white shark during the Early Cretaceous. While regarded as one of the largest and most powerful predators to have ever lived, the megalodon is only known from fragmentary remains, and its appearance and maximum size are uncertain. Scientists differ on whether it would have more closely resembled a stockier version of the great white shark, the whale shark (''Rhincodon typus''), the basking shark (''Cetorhinus maximus'') or the sand tiger shark (''Carcharias taurus''). The most recent estimate with the least error range suggests a maximum length e ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Cetotheriidae
Cetotheriidae is a family of baleen whales (parvorder Mysticeti). The family is known to have existed from the Late Oligocene to the Early Pleistocene before going extinct. Although some phylogenetic studies conducted by recovered the living pygmy right whale as a member of Cetotheriidae, making the pygmy right whale the only living cetotheriid, other authors either dispute this placement or recover Neobalaenidae as a sister group to Cetotheriidae. Taxonomy After its description by Brant in 1872, Cetotheriidae was used as a wastebasket taxon for baleen whales which were not assignable to extant whale families. Comparing the cranial and mandibular morphology of 23 taxa (including late archaeocetes and both fossil and extant mysticetes), found Cetotheriidae in this traditional sense to be polyphyletic. Based on ten cranial characters, they also concluded that of the twelve included fossil baleen-bearing mysticetes, six formed a monophyletic group, Cetotheriidae ''sensu stricto' ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Pisco Formation
The Pisco Formation is a geologic formation located in Peru, on the southern coastal desert of Ica, Peru, Ica and Arequipa. The approximately thick formation was deposited in the Pisco Basin, spanning an age from the Miocene, Middle Miocene up to the Early Pleistocene, roughly from 15 to 2 Ma. The tuffaceous sandstones, diatomaceous siltstones, Conglomerate (geology), conglomerates and dolomite (rock), dolomites were deposited in a lagoonal to near-shore depositional environment, environment, in bays similar to other Pacific South American formations as the Caldera Basin, Bahía Inglesa and Coquimbo Formations of Chile. Several specialists consider the Pisco Formation one of the most important Lagerstätten,Brand et al., 2004Brand et al., 2011 based on the large amount of exceptionally preserved marine fossils, including sharks (most notably megalodon), penguins, whales, dolphins, birds, marine crocodiles and aquatic giant sloths. Famous fossils found in these layers include the ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Baleen Whales
Baleen whales (systematic name Mysticeti), also known as whalebone whales, are a parvorder of carnivorous marine mammals of the infraorder Cetacea (whales, dolphins and porpoises) which use keratinaceous baleen plates (or "whalebone") in their mouths to sieve planktonic creatures from the water. Mysticeti comprises the families Balaenidae (right and bowhead whales), Balaenopteridae (rorquals and the gray whale), and Cetotheriidae (the pygmy right whale). There are currently 16 species of baleen whales. While cetaceans were historically thought to have descended from mesonychids, molecular evidence instead supports them as a clade of even-toed ungulates (Artiodactyla). Baleen whales split from toothed whales (Odontoceti) around 34 million years ago. Baleen whales range in size from the and pygmy right whale to the and blue whale, the largest known animal to have ever existed. They are sexually dimorphic. Baleen whales can have streamlined or large bodies, depending on ... [...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] |
Odobenocetops
''Odobenocetops'' () is an extinct genus of small toothed whale known from Peru and Chile. Its fossils are found in Neogene-aged marine strata dating from the Tortonian to the Zanclean. It had two tusks, and, in some fossils, one tusk was longer than the other. Phylogeny ''Odobenocetops'' can be identified as a cetacean based on several features unique to this order: # The presence of large air sinuses in the auditory region connected to large pterygoid sinuses. # The large supraorbital process of the frontal bone overhanging the orbital region. # Narial fossae opening dorsally (thought not at the apex of the skull like in other cetaceans.) # The absence of a true cribriform plate (a bony blade separating the nares). In ''Odobenocetops'', a group of foramina in this plate allows the passage of olfactory nerves connected to the small olfactory lobes in the brain. In other cetaceans, the olfactory nerves are similarly present but strongly reduced. # The elbow joint is immobile, as ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Acrophoca
''Acrophoca longirostris'', sometimes called the swan-necked seal, is an extinct genus of Late Miocene pinniped. It was thought to have been the ancestor of the modern leopard seal, however it is now thought to be a species of monk seal. Taxonomy The fossils of ''A. longirostris'' have been discovered in the Pisco Formation of Peru and the Bahía Inglesa Formation of Chile. When it was first described in 1981, it was thought to have been closely related to the lobodontine seals which includes the modern day leopard seal (''Hydrurga leptonyx''), the crabeater seal (''Lobodon carcinophaga''), the Weddell seal (''Leptonychotes weddelli''), and the Ross seal (''Ommatophoca rossii''). However, it is now thought to be a basal species of monk seal of the subfamily Monachinae, closely related to the extinct seal ''Piscophoca''. Description ''Acrophoca'' was around long, and was not as well-adapted to swimming as its descendants, possessing less developed flippers and a less streamli ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Sloth
Sloths are a group of Neotropical xenarthran mammals constituting the suborder Folivora, including the extant arboreal tree sloths and extinct terrestrial ground sloths. Noted for their slowness of movement, tree sloths spend most of their lives hanging upside down in the trees of the tropical rainforests of South America and Central America. Sloths are considered to be most closely related to anteaters, together making up the xenarthran order Pilosa. There are six extant sloth species in two genera – '' Bradypus'' (three–toed sloths) and '' Choloepus'' (two–toed sloths). Despite this traditional naming, all sloths have three toes on each rear limb-- although two-toed sloths have only two digits on each forelimb. The two groups of sloths are from different, distantly related families, and are thought to have evolved their morphology via parallel evolution from terrestrial ancestors. Besides the extant species, many species of ground sloths ranging up to the size of ele ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Thalassocnus
''Thalassocnus'' is an extinct genus of semiaquatic ground sloths from the Miocene and Pliocene of the Pacific South American coast. It is monotypic within the subfamily Thalassocninae. The five species—''T. antiquus'', ''T. natans'', ''T. littoralis'', ''T. carolomartini'', and ''T. yuacensis''—represent a chronospecies, a population gradually adapting to marine life in one direct lineage. They are the only known aquatic sloths, but they may have also been adapted to a terrestrial lifestyle. They have been found in the Pisco Formation of Peru, the Tafna Formation of Argentina, and the Bahía Inglesa, Coquimbo, and Horcón formations of Chile. Thalassocninae has been placed in both the families Megatheriidae and Nothrotheriidae. ''Thalassocnus'' evolved several marine adaptations over the course of 4 million years, such as dense and heavy bones to counteract buoyancy, the internal nostrils migrating farther into the head to help with breathing while completely submerged, ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Atlantic
The Atlantic Ocean is the second-largest of the world's five oceans, with an area of about . It covers approximately 20% of Earth's surface and about 29% of its water surface area. It is known to separate the " Old World" of Africa, Europe and Asia from the "New World" of the Americas in the European perception of the World. The Atlantic Ocean occupies an elongated, S-shaped basin extending longitudinally between Europe and Africa to the east, and North and South America to the west. As one component of the interconnected World Ocean, it is connected in the north to the Arctic Ocean, to the Pacific Ocean in the southwest, the Indian Ocean in the southeast, and the Southern Ocean in the south (other definitions describe the Atlantic as extending southward to Antarctica). The Atlantic Ocean is divided in two parts, by the Equatorial Counter Current, with the North(ern) Atlantic Ocean and the South(ern) Atlantic Ocean split at about 8°N. Scientific explorations of the Atlanti ... [...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] |
