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Pelagiarctos
''Pelagiarctos'' was a genus of walrus that lived during the Mid Miocene, approx. 13-15 mya. Its remains have been found in the Sharktooth Hill Bonebed, in Kern County, California. It was originally described as an Otariidae, though it is now usually considered to be a basal Odobenidae. Anatomy To date, the only material of ''Pelagiarctos'' that has been found includes a handful of partial mandibles. The mandibles themselves are approximately the same size as those of the contemporaneous pinniped '' Allodesmus kernensis'', but differ in that the cheek teeth have two roots (instead of one, as in ''Allodesmus'') and that the dentary itself is much thicker. They are also highly vascularized and covered in unusually large mental foramina, indicating that ''Pelagiarctos'' may have had somewhat fleshy lips. The cheek teeth resemble those of several terrestrial carnivores, specifically borophagine dogs and hyaenids. This, coupled with the robust dentary, indicates that ''Pelag ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Odobenid
Odobenidae is a family of pinniped Pinnipeds (pronounced ), commonly known as seals, are a widely range (biology), distributed and diverse clade of carnivorous, fin-footed, semiaquatic, mostly marine mammals. They comprise the extant taxon, extant families Odobenidae (whose onl ...s, of which the only extant species is the walrus (''Odobenus rosmarus''). In the past, however, the group was much more diverse, and includes more than a dozen fossil genera. Taxonomy All genera, except ''Walrus, Odobenus'', are extinct. *†''Archaeodobenus'' *†''Prototaria'' *†''Proneotherium'' *†''Nanodobenus'' *†''Neotherium'' *†''Imagotaria'' *†''Kamtschatarctos'' *†''Pelagiarctos'' *†''Pontolis'' *†''Pseudotaria'' *†''Titanotaria'' *Clade Neodobenia **†''Gomphotaria'' **Subfamily Dusignathinae ***†''Dusignathus'' **Subfamily Odobeninae ***†''Aivukus'' ***†''Ontocetus'' ***†''Pliopedia'' ***†''Protodobenus'' ***†''Valenictus'' ***''Walrus, Odobenus'' In re ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Miocene
The Miocene ( ) is the first epoch (geology), 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 followed the Oligocene and preceded 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 distinct global events but by regionally defined transitions from the warmer Oligocene to the cooler Pliocene Epoch. During the Early Miocene, Afro-Arabia collided with Eurasia, severing the connection between the Mediterranean and Indian Oceans, and allowing the interchange of fauna between Eurasia and Africa, including the dispersal of proboscideans and Ape, hominoids into Eurasia. During the late Miocene, the conn ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Sharktooth Hill
The Temblor Formation is a geologic formation in California. It preserves fossils dating back from the Late Oligocene to the Middle Miocene of the Neogene period. It is notable for the famous Sharktooth Hill deposit (otherwise known as Ernst Quarry). Fossils Vertebrates Cartilagenous fishes = Sharks = * '' Carcharias'' * '' Cephaloscyllium'' * '' Cetorhinus'' * †'' Carcharocles megalodon'' Boessenecker, Ehret, D, Long, D, Churchill, M, Martin, E, Boessenecker, S. The Early Pliocene extinction of the mega-toothed shark ''Otodus megalodon'': a view from the eastern north Pacific. PeerJ. 2019 Feb 13;7:e6088. doi: 10.7717/peerj.6088. eCollection 2019. * †'' Galeocerdo aduncus'' * †'' Hemipristis serra'' * '' Heterodontus'' * '' Hexanchus'' * †''Isurus desori'' * †'' Isurus hastalis'' * †'' Isurus planus''Malchow, A. 2009. MIOCENE SHARK TOOTH HILL LOCALITY, KERN COUNTY, CALIFORNIA. Geological Society of America North-Central Section - 43rd Annual Meeting (2-3 Apri ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Carnivores
A carnivore , or meat-eater (Latin, ''caro'', genitive ''carnis'', meaning meat or "flesh" and ''vorare'' meaning "to devour"), is an animal or plant whose nutrition and energy requirements are met by consumption of animal tissues (mainly muscle, fat and other soft tissues) as food, whether through predation or scavenging. Nomenclature Mammal order The technical term for mammals in the order Carnivora is ''carnivoran'', and they are so-named because most member species in the group have a carnivorous diet, but the similarity of the name of the order and the name of the diet causes confusion. Many but not all carnivorans are meat eaters; a few, such as the large and small cats (Felidae) are ''obligate'' carnivores (see below). Other classes of carnivore are highly variable. The ursids (bears), for example: while the Arctic polar bear eats meat almost exclusively (more than 90% of its diet is meat), almost all other bear species are omnivorous, and one species, the giant ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Puffinus
''Puffinus'' is a genus of seabirds in the order Procellariiformes that contains about 20 small to medium-sized shearwaters. Two other shearwater genera are named: '' Calonectris'', which comprises three or four large shearwaters, and '' Ardenna'' with another seven species (formerly often included within ''Puffinus''). The taxonomy of this group is the cause of much debate, and the number of recognised species varies with the source. The species in this group are long-winged birds, dark brown or black above, and white to dark brown below. They are pelagic outside the breeding season. They are most common in temperate and cold waters. These tubenose birds fly with stiff wings, and use a shearing flight technique to move across wave fronts with the minimum of active flight. Some small species, such as the Manx shearwater, are cruciform in flight, with their long wings held directly out from their bodies. Many are long-distance migrants, perhaps most spectacularly the sooty an ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Osteodontornis
''Osteodontornis'' is an extinct seabird genus. It contains a single named species, ''Osteodontornis orri'' (Orr's bony-toothed bird, in literal translation of its scientific name), which was described quite exactly one century after the first species of the Pelagornithidae ('' Pelagornis miocaenus'') was. ''O. orri'' was named after Santa Barbara Museum of Natural History paleontologist Phil C. Orr, for his recognition of the importance of the specimen. The bony-toothed or pseudotooth birds were initially believed to be related to albatrosses in the Procellariiformes, but actually they seem to be rather close relatives of either pelicans and storks, or of waterfowl, and are here placed in the order Odontopterygiformes to account for this uncertainty. Also, their internal taxonomy is not well-resolved. An earlier-described pseudotooth bird, '' Cyphornis magnus'' from Vancouver Island (Canada), was believed to be of Eocene age but is nowadays assumed to have lived about twenty mil ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Psephophorus
''Psephophorus'' is an extinct genus of sea turtle that lived from the Oligocene to the Pliocene. Its remains have been found in Europe, Africa, North America, and New Zealand. It was first named by Hermann von Meyer in 1847, and contains seven species, ''P. polygonus'', ''P. calvertensis'', ''P. eocaenus'', ''P. oregonesis'', ''P. californiensis'', ''P. rupeliensis'',''Proceedings''; page 8. By the Zoological Society of London; published 1891. Retrieved on June 28th, 2008. ''P. scaldii'', and a species discovered in 1995, ''P. terrypratchetti''. ''Psephophorus'' is the only Miocene dermochelyid turtle found in Europe. One species of ''Psephophorus'' could measure up to ten feet in length. Discovery and identification Von Meyer originally named ''Psephophorus'' in 1846. At first he was unable to identify the creature beyond its dermal plates, but when he later received a drawing he was able to describe the specimen, which was then in Pressburg, as a fragment of a carapace, whi ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Carcharocles
''Otodus'' is an extinct, cosmopolitan genus of mackerel shark which lived from the Paleocene to the Pliocene epoch. The name ''Otodus'' comes from Ancient Greek (, meaning "ear") and (, meaning "tooth") – thus, "ear-shaped tooth". Description All species are known from their fossilized teeth, and four of them (''O. obliquus'', ''O. auriculatus'', ''O. angustidens'' and ''O. megalodon'') are also known from their fossilized vertebral centra. Like other elasmobranchs, the skeleton of ''Otodus'' was composed of cartilage and not bone, resulting in relatively few preserved skeletal structures appearing within the fossil record. The teeth of this shark are large with triangular crown, smooth cutting edges, and visible cusps on the roots. Some ''Otodus'' teeth also show signs of evolving serrations. Size estimation The fossils of ''Otodus'' sharks indicate that they were very large macro-predatory sharks. The largest known teeth of ''O. obliquus'' measure about in height. The ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Sphyrna
''Sphyrna'' is a genus of hammerhead sharks with a cosmopolitan distribution in the world's oceans. Members of ''Sphyrna'' have a tendency to inhabit coastal waters along the intertidal zone rather than the open ocean, as their prey such as invertebrates, fish, rays, small crustaceans, and other benthic organisms hide in the sands and sediment along these zones. Members of ''Sphyrna'' are also known by synonyms such as ''Zygaena'', ''Cestracion'', and ''Sphyrichthys''. The earliest species described of this genus was '' Sphyrna zygaena'' by Carl Linnaeus in 1758, while the latest described member, '' Sphyrna alleni'', was described in 2024. The genus name comes from the Greek word ''sphyra'' "hammer", it is also where the family name Sphyrnidae comes from. Species The recognized species in this genus are: ;Extant * '' Sphyrna alleni'' Gonzalez, Postaire, Driggers, Caballero, & Chapman, 2024 (shovelbill shark)Gonzalez, C., Postaire, B., Driggers, W., Caballero, S. & Ch ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Isurus
''Isurus'' (meaning "equal tail") is a genus of mackerel sharks in the family Lamnidae, commonly known as the mako sharks. They are largely pelagic, and are fast, predatory fish capable of swimming at speeds of up to . Fossil history and evolution Although fossil teeth of ''Isurus'' have been reported from as early as the Late Cretaceous, they are likely to be of a shark with a similar dentition, '' Cretoxyrhina''; since at one point they were considered to be the same (now defunct) genus ''Oxyrhina'', and modern referrals to ''Isurus'' in the Cretaceous are scant. The earliest appearance of ''Isurus'' proper seems to be during the Oligocene with ''Isurus desori''. There has been much debate and speculation about the evolutionary origin and relationships between ''Isurus'' and its closest relatives, including the extant great white shark (''Carcharodon carcharias''). Molecular clock analyses place the last common ancestor of ''Isurus'' and '' Carcharodon'' between 43–60 mil ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
North Pacific
The Pacific Ocean is the largest and deepest of Earth's five oceanic divisions. It extends from the Arctic Ocean in the north to the Southern Ocean, or, depending on the definition, to Antarctica in the south, and is bounded by the continents of Asia and Australia in the west and the Americas in the east. At in area (as defined with a southern Antarctic border), the Pacific Ocean is the largest division of the World Ocean and the hydrosphere and covers approximately 46% of Earth's water surface and about 32% of the planet's total surface area, larger than its entire land area ().Pacific Ocean . '' Britannica Concise.'' 2008: Encyclopædia Britannica, Inc. The centers of both the [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
