|
Almejas Formation
The Almejas Formation is a geologic formation in Mexico. It preserves fossils dating back to the Late Miocene to Early Pliocene of the Neogene period. Fossil content Various fossils have been found in the formation:Arroyo Delphin at .org Mammals * '' Aivukus cedrosensis'' * '' Albireo whistleri'' * '' Balaenoptera sp.'' * ''[...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Formation (stratigraphy)
A geological formation, or simply formation, is a body of rock having a consistent set of physical characteristics (lithology) that distinguishes it from adjacent bodies of rock, and which occupies a particular position in the layers of rock exposed in a geographical region (the stratigraphic column). It is the fundamental unit of lithostratigraphy, the study of strata or rock layers. A formation must be large enough that it can be mapped at the surface or traced in the subsurface. Formations are otherwise not defined by the thickness (geology), thickness of their rock strata, which can vary widely. They are usually, but not universally, tabular in form. They may consist of a single lithology (rock type), or of alternating beds of two or more lithologies, or even a heterogeneous mixture of lithologies, so long as this distinguishes them from adjacent bodies of rock. The concept of a geologic formation goes back to the beginnings of modern scientific geology. The term was used by ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Carcharhinus
''Carcharhinus'' is the type genus of the family (biology), family Carcharhinidae, the requiem sharks. One of 12 genera in its family, it contains over half of the species therein. It contains 35 extant and eight extinct species to date, with likely more species yet to be described. Species Extant T Type species Fossil See also * List of prehistoric cartilaginous fish genera References Bibliography * * * * * * * {{Authority control Carcharhinus, Shark genera Extant Eocene first appearances Taxa named by Henri Marie Ducrotay de Blainville ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Carcharodon
''Carcharodon'' (meaning "jagged/sharp tooth" in Ancient Greek) is a genus of sharks within the family Lamnidae, colloquially called the "white sharks." The only extant member is the great white shark (''Carcharodon carcharias''). Extinct species include '' C. hubbelli'' and '' C. hastalis.'' The first appearance of the genus may have been as early as the Early Miocene or Late Oligocene. Carcharocles megalodon is still argued by some paleontologists (e.g. Michael D. Gottfried, Leonard Compagno, and Ewan Fordyce) to be a close relative of ''Carcharodon carcharias'' - as well as being in the same genus. When Megalodon belonged to this genus it had the scientific name ''Carcharodon megalodon''. More recently, Megalodon has been assigned by most scientists to either the genus ''Carcharocles'' or ''Otodus''. Fossil History and Evolution The fossil ancestry of ''Carcharodon'' is an active area of research and debate, given the dearth of the fossil record and the incompleteness of f ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Synthliboramphus
''Synthliboramphus'' is a small genus of seabirds in the auk family from the North Pacific. The genus name ''Synthliboramphus'' is from Ancient Greek ''sunthlibo'', "to compress", and ''rhamphos'', "bill". The English name "Murrelet" is a diminutive of "murre", a word of uncertain origins, but which may imitate the call of the common guillemot. Taxonomy The genus ''Synthliboramphus'' was introduced in 1837 by the German born naturalist Johann Friedrich von Brandt. The type genus was subsequently designated by George Robert Gray as the ancient murrelet. The genus name combines Ancient Greek ''sunthlibō'' meaning "to compress" with ''rhamphos'' meaning "bill". The genus contains five species: The first two species were formally considered conspecific, and are sometimes separated in the genus ''Endomychura''. Fossil remains of two prehistoric species are known: an undescribed ''Synthliboramphus'' sp. from the Late Miocene or Early Pliocene (c. 5 mya) of Cedros Island, Me ... [...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] |
Morus (bird)
Gannets are seabirds comprising the genus ''Morus'' in the family Sulidae, closely related to boobies. They are known as 'solan' or 'solan goose' in Scotland. A common misconception is that the Scottish name is 'guga' but this is the Gaelic name referring to the chicks only. 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 t ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Megapaloelodus
''Megapaloelodus'' is an extinct genus of stem flamingo of the family Palaelodidae. ''Megapaloelodus'' is primarily known from Miocene America, from South Dakota and Oregon in the north to Argentina in the south, but the species ''Megapaloelodus goliath'' was found in Europe. Additionally, one unnamed species was discovered in Miocene sediments from Namibia. Due to a lack of skull material, little can be said about the ecology of ''Megapaloelodus''. Species of this genus are typically larger than those of ''Palaelodus'' and appear to have inhabited similar brackish lake environments. Additionally, they may have been capable of "locking" their legs in a standing position. History and naming ''Megapaloelodus'' was named by American Alden H. Miller in 1944 on the basis of a fossil femur and tarsometatarsus collected from the lower Miocene Rosebud Formation of South Dakota. Recognizing similarities to fossils of '' Palaelodus'', Miller described the material as a new genus of phoenic ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Mancalla
''Mancalla'' is an extinct genus of prehistoric flightless alcids that lived on the Pacific coast of today's California and Mexico during the Late Miocene to Early Pliocene Early may refer to: Places in the United States * Early, Iowa, a city * Early, Texas, a city * Early Branch, a stream in Missouri * Early County, Georgia * Fort Early, Georgia, an early 19th century fort Music * Early B, stage name of Jamaican d .... References Auks Extinct flightless birds Neogene birds Prehistoric bird genera {{Charadriiformes-stub ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Cerorhinca Minor
''Cerorhinca'' is a genus of auk containing the rhinoceros auklet and several fossil species. Evolutionary history The genus ''Cerorhinca'' evolved in the North Pacific during the Miocene. Fossils have been found as far south as Baja California. While previously only known from the Pacific region, an unnamed species has been discovered from the Pliocene of North Carolina North Carolina ( ) is a U.S. state, state in the Southeastern United States, Southeastern region of the United States. It is bordered by Virginia to the north, the Atlantic Ocean to the east, South Carolina to the south, Georgia (U.S. stat ..., suggesting the genus had a much wider distribution in the past. References {{Authority control Bird genera Bird genera with one living species Taxa named by Charles Lucien Bonaparte Alcidae ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Thalassoleon
''Thalassoleon'' ("sea lion" ) is an extinct genus of large fur seal. ''Thalassoleon'' inhabited the Northern Pacific Ocean in latest Miocene and early Pliocene. Fossils of ''T. mexicanus'' are known from Baja California and southern California. ''T. macnallyae'' is known from central California, and ''T. inouei'' (which may be a synonym of ''T. macnallyae'') is known from Japan. ''Thalassoleon'' could be the ancestor of the modern northern fur seal The northern fur seal (''Callorhinus ursinus'') is an eared seal found along the north Pacific Ocean, the Bering Sea, and the Sea of Okhotsk. It is the largest member of the fur seal subfamily (Arctocephalinae) and the only living species in the .... ''T. mexicanus'' was comparable in size to the largest modern fur seals, with an old-male skull length of 272 mm and an estimated minimal weight of 295–318 kg (650–700 lb). Holotype of ''T. macnallyae'', UCMP 112809, is a male equal in size to ''T. mexicanus''. Re ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Praekogia
''Praekogia'' is an extinct genus of cetacean in the family Kogiidae Kogiidae is a family comprising at least two extant species of Cetacea, the pygmy (''Kogia breviceps)'' and dwarf (''K. sima)'' sperm whales. As their common names suggest, they somewhat resemble sperm whales, with squared heads and small lower ... that lived during the Miocene, containing one species: ''P. cedrosensis''. Fossils have been found in Mexico (Baja California). References Cetaceans Miocene extinctions Miocene first appearances Neogene Mexico Fossils of Mexico Fossil taxa described in 1973 {{paleo-whale-stub ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
