|
Ñandú
The rhea ( ), also known as the ñandu ( ) or South American ostrich, is a South American ratite (flightless bird without a keel (bird anatomy), keel on the sternum bone) of the order Rheiformes. They are distantly related to the two African Ostrich, ostriches and Australia's emu (the largest, second-largest and third-largest living ratites, respectively), with rheas placing just behind the emu in height and overall size. Most taxonomic authorities recognize two Extant taxon, extant species: the Greater rhea, greater or American rhea (''Rhea americana''), and the Darwin's rhea, lesser or Darwin's rhea (''Rhea pennata''). The International Union for Conservation of Nature (IUCN) classifies the puna rhea as another species instead of a subspecies of the lesser rhea. The IUCN currently rates the greater and puna rheas as near-threatened in their native ranges, while Darwin's rhea is of least concern, having recovered from past threats to its survival. In addition, the feral populat ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Pterocnemia
Darwin's rhea or the lesser rhea (''Rhea pennata'') is a large flightless bird, the smaller of the two Extant taxon, extant species of rhea (bird), rheas. It is found in the Altiplano and Patagonia in South America. Description The lesser rhea stands at tall. Length is and weight is . Like most ratites, it has a small head and a small Beak, bill, the latter measuring , but has long legs and a long neck. It has relatively larger wings than other ratites, enabling it to run particularly well. It can reach speeds of 60 km/h (37 mph), enabling it to outrun predators. The sharp claws on the toes are effective weapons. Their feathers are similar to those of ostriches, in that they have no Wiktionary:aftershaft, aftershaft.Perrins, C. (1987) Their plumage is spotted brown and white, and the upper part of their Tarsus (skeleton), tarsus is feathered. The Tarsus (skeleton), tarsus is long and has 18 horizontal plates on the front. Etymology It is known as ''ñandú petiso ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Greater Rhea
The greater rhea (''Rhea americana'') is a species of flightless bird native to eastern South America. Other names for the greater rhea include the grey, common, or American rhea; ema (Portuguese (language), Portuguese); or ñandú (Guaraní language, Guaraní and Spanish language, Spanish). One of two species in the genus ''Rhea (bird), Rhea'', in the Family (biology), family Rheidae, it inhabits a variety of open areas, such as grasslands, savanna or grassy wetlands. Weighing , the greater rhea is the largest native bird in the Americas. In the wild, the greater rhea has a life expectancy of 10.5 years. It is also notable for its reproductive habits, and for the fact that a population has established itself in Northern Germany in recent years. The species is listed as Near Threatened by the IUCN. Taxonomy The greater rhea was Species description, formally described in 1758 by the Swedish naturalist Carl Linnaeus in the 10th edition of Systema Naturae, tenth edition of his ''Syst ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Rhea Americana
The greater rhea (''Rhea americana'') is a species of flightless bird native to eastern South America. Other names for the greater rhea include the grey, common, or American rhea; ema ( Portuguese); or ñandú ( Guaraní and Spanish). One of two species in the genus '' Rhea'', in the family Rheidae, it inhabits a variety of open areas, such as grasslands, savanna or grassy wetlands. Weighing , the greater rhea is the largest native bird in the Americas. In the wild, the greater rhea has a life expectancy of 10.5 years. It is also notable for its reproductive habits, and for the fact that a population has established itself in Northern Germany in recent years. The species is listed as Near Threatened by the IUCN. Taxonomy The greater rhea was formally described in 1758 by the Swedish naturalist Carl Linnaeus in the tenth edition of his ''Systema Naturae''. He placed it with the ostriches in the genus '' Struthio'' and coined the binomial name ''Struthio americanus''. Linnaeus ba ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Lesser Rhea
Darwin's rhea or the lesser rhea (''Rhea pennata'') is a large flightless bird, the smaller of the two extant species of rheas. It is found in the Altiplano and Patagonia in South America. Description The lesser rhea stands at tall. Length is and weight is . Like most ratites, it has a small head and a small bill, the latter measuring , but has long legs and a long neck. It has relatively larger wings than other ratites, enabling it to run particularly well. It can reach speeds of 60 km/h (37 mph), enabling it to outrun predators. The sharp claws on the toes are effective weapons. Their feathers are similar to those of ostriches, in that they have no aftershaft.Perrins, C. (1987) Their plumage is spotted brown and white, and the upper part of their tarsus is feathered. The tarsus is long and has 18 horizontal plates on the front. Etymology It is known as ''ñandú petiso'', or ''ñandú del norte'', in Argentina, where the majority live. Other names are ''su ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Ratite
Ratites () are a polyphyletic group consisting of all birds within the infraclass Palaeognathae that lack keels and cannot fly. They are mostly large, long-necked, and long-legged, the exception being the kiwi, which is also the only nocturnal extant ratite. The understanding of relationships within the paleognath clade has been in flux. Previously, all the flightless members had been assigned to the order Struthioniformes, which is more recently regarded as containing only the ostrich. The modern bird superorder Palaeognathae consists of ratites and the flighted Neotropic tinamous (compare to Neognathae). Unlike other flightless birds, the ratites have no keel on their sternum—hence the name, from the Latin ('raft', a vessel which has no keel—in contradistinction to extant flighted birds with a keel). Without this to anchor their wing muscles, they could not have flown even if they had developed suitable wings. Ratites are a polyphyletic group; tinamous fall within the ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Flightless Bird
Flightless birds are birds that cannot Bird flight, fly, as they have, through evolution, lost the ability to. There are over 60 extant species, including the well-known ratites (ostriches, emus, cassowary, cassowaries, Rhea (bird), rheas, and Kiwi (bird), kiwis) and penguins. The smallest flightless bird is the Inaccessible Island rail (length 12.5 cm, weight 34.7 g). The largest (both heaviest and tallest) flightless bird, which is also the largest living bird in general, is the common ostrich (2.7 m, 156 kg). Many domesticated birds, such as the domestic chicken and domestic duck, have lost the ability to fly for extended periods, although their ancestral species, the red junglefowl and mallard, respectively, are capable of extended flight. A few particularly bred birds, such as the Broad Breasted White turkey, have become totally flightless as a result of selective breeding; the birds were bred to grow massive breast meat that weighs too much for the bird's wings ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Keel (bird Anatomy)
A ''keel'' or ''carina'' (: carinae) in bird anatomy is an extension of the sternum (breastbone) which runs axially along the midline of the sternum and extends outward, perpendicular to the plane of the ribs. The keel provides an anchor to which a bird's wing muscles attach, thereby providing adequate leverage for flight. Not all birds have keels; in particular, some flightless birds lack a keel structure. Some flightless birds have a keel, such as the penguin; but in the penguin's case, its wings are too small for its body, so flight would require flapping its wings too fast to be practical. Historically, the presence or absence of a pronounced keel structure was used as a broad classification of birds into two orders: Carinatae (from ''carina'', "keel"), having a pronounced keel; and ratites (from ''ratis'', "raft"referring to the flatness of the sternum), having a subtle keel structure or lacking one entirely. However, this classification has become disused as evolutio ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Messinian
The Messinian is in the geologic timescale the last age or uppermost stage of the Miocene. It spans the time between 7.246 ± 0.005 Ma and 5.333 ± 0.005 Ma (million years ago). It follows the Tortonian and is followed by the Zanclean, the first age of the Pliocene. The Messinian overlaps the Turolian European Land Mammal Mega Zone (more precisely MN 12 and 13) and the Pontian Central European Paratethys Stage. It also overlaps the late Huayquerian and early Montehermosan South American Land Mammal Ages, and falls inside the more extensive Hemphillian North American Land Mammal Age. During the Messinian, around 6 million years ago, the Messinian salinity crisis took place, which brought about repeated desiccations of the Mediterranean Sea. Definition The Messinian was introduced by Swiss stratigrapher Karl Mayer-Eymar in 1867. Its name comes from the Italian city of Messina on Sicily, where the Messinian evaporite deposit is of the same age. The base of the Messinian ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Sternum
The sternum (: sternums or sterna) or breastbone is a long flat bone located in the central part of the chest. It connects to the ribs via cartilage and forms the front of the rib cage, thus helping to protect the heart, lungs, and major blood vessels from injury. Shaped roughly like a necktie, it is one of the largest and longest flat bones of the body. Its three regions are the manubrium, the body, and the xiphoid process. The word ''sternum'' originates from Ancient Greek στέρνον (''stérnon'') 'chest'. Structure The sternum is a narrow, flat bone, forming the middle portion of the front of the chest. The top of the sternum supports the clavicles (collarbones) and its edges join with the costal cartilages of the first two pairs of ribs. The inner surface of the sternum is also the attachment of the sternopericardial ligaments. Its top is also connected to the sternocleidomastoid muscle. The sternum consists of three main parts, listed from the top: * Man ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
