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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] |
Acrophoca BW
''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] |
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] |
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] |
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] |
Monachinae
Monachinae (known colloquially as "Southern seals") is a subfamily of Earless seal, Phocidae whose distribution is found in the tropical, temperate and polar regions of the southern hemisphere, though in the distant past fossil representatives have been found on both sides of the North Atlantic Ocean. The difference between members of this group and members of Phocinae is in monachines the hindclaws are greatly reduced in size. Furthermore, all species have 34 chromosomes. There are three tribes recognized here: Monk seal, Monachini (monk seals), Elephant seal, Miroungini (elephant seals), and Lobodontini (Antarctic seals and a handful of Afroamerican fossil genera). While today represented by eight extant and Caribbean monk seal, one recently extinct species, Monachinae had an incredibly enriched fossil diversity that went into decline soon to be replaced by southern species of sea lions and fur seals. References Pinnipeds Mammal subfamilies {{carnivora-stub ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Miocene Pinnipeds
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 late ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Prehistoric Carnivoran 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. Th ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
True Seals
The earless seals, phocids or true seals are one of the three main groups of mammals within the seal lineage, Pinnipedia. All true seals are members of the family Phocidae (). They are sometimes called crawling seals to distinguish them from the fur seals and sea lions of the family Otariidae. Seals live in the oceans of both hemispheres and, with the exception of the more tropical monk seals, are mostly confined to polar, subpolar, and temperate climates. The Baikal seal is the only species of exclusively freshwater seal. Taxonomy and evolution Evolution The earliest known fossil earless seal is ''Noriphoca gaudini'' from the late Oligocene or earliest Miocene ( Aquitanian) of Italy. Other early fossil phocids date from the mid-Miocene, 15 million years ago in the north Atlantic. Until recently, many researchers believed that phocids evolved separately from otariids and odobenids; and that they evolved from otter-like animals, such as ''Potamotherium'', which inhabited E ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Cormorant
Phalacrocoracidae is a family of approximately 40 species of aquatic birds commonly known as cormorants and shags. Several different classifications of the family have been proposed, but in 2021 the IOC adopted a consensus taxonomy of seven genera. The great cormorant (''Phalacrocorax carbo'') and the common shag (''Gulosus aristotelis'') are the only two species of the family commonly encountered in Britain and Ireland and "cormorant" and "shag" appellations have been later assigned to different species in the family somewhat haphazardly. Cormorants and shags are medium-to-large birds, with body weight in the range of and wing span of . The majority of species have dark feathers. The bill is long, thin and hooked. Their feet have webbing between all four toes. All species are fish-eaters, catching the prey by diving from the surface. They are excellent divers, and under water they propel themselves with their feet with help from their wings; some cormorant species have been ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Gannet
Gannets are seabirds comprising the genus ''Morus'' in the family Sulidae, closely related to boobies. Gannets are large white birds with yellowish heads; black-tipped wings; and long bills. Northern gannets are the largest seabirds in the North Atlantic, having a wingspan of up to . The other two species occur in the temperate seas around southern Africa, southern Australia, and New Zealand. Etymology "Gannet" is derived from Old English ''ganot'' meaning "strong or masculine", ultimately from the same Old Germanic root as "gander". Taxonomy ''Morus'' is derived from Ancient Greek ''moros'' "stupid" or "foolish" due to lack of fear shown by breeding gannets and boobies, allowing them to be easily killed. Behaviour Hunting Gannets hunt fish by diving into the sea from a height of and pursuing their prey underwater, and have a number of adaptations: * They have no external nostrils; they are located inside the mouth, instead. * They have air sacs in the face and ch ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Bottlenose Dolphins
Bottlenose dolphins are aquatic mammals in the genus ''Tursiops.'' They are common, cosmopolitan members of the family Delphinidae, the family of oceanic dolphins. Molecular studies show the genus definitively contains two species: the common bottlenose dolphin (''Tursiops truncatus'') and the Indo-Pacific bottlenose dolphin (''Tursiops aduncus''). Others, like the Burrunan dolphin (''Tursiops (aduncus) australis''), may be alternately considered their own species or be subspecies of ''T. aduncus''. Bottlenose dolphins inhabit warm and temperate seas worldwide, being found everywhere except for the Arctic and Antarctic Circle regions. Their name derives from the Latin ''tursio'' (dolphin) and ''truncatus'' for their characteristic truncated teeth. Numerous investigations of bottlenose dolphin intelligence have been conducted, examining mimicry, use of artificial language, object categorization, and self-recognition. They can use tools (sponging; using marine sponges to forage ... [...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] |
