Eutreptornis
Eutreptornis ("changing bird")is a genus of extinct possible cariamiforme bird from the Late Eocene of Utah. It is traditionally considered to be a bathornithid, though a combination of the relative incompleteness of the material alongside some differences from other bathornithids have raised some suspicions about this affiliation. Description ''Eutreptornis'' is currently represented by a single type species, ''E. uintae'', in turn represented by a tibiotarsus and tarsometatarsus from the Uinta Formation of Utah. Biology It is represented by the smallest bathornithid remains known. Due to the incompleteness of its remains it is unclear whereas it was flightless like other bathornithids. It was, however, most certainly a terrestrial predator, perhaps akin to its closest living relatives, the seriemas. Ecology ''Eutreptornis'' co-existed with a rich mammalian megafauna, such as the brontothere ''Megacerops ''Megacerops'' ("large-horned face", from '' méga-'' "large" ... [...More Info...]       [...Related Items...]     OR:     [Wikipedia]   [Google]   [Baidu]   |
|
Bathornithid
Bathornithidae is an extinct family of birds from the Eocene to Miocene of North America. Part of Cariamiformes, they are related to the still extant seriemas and the also extinct Phorusrhacidae. They were likely similar in habits, being terrestrial, long-legged predators, some of which attained massive sizes. It has been suggested that most, if not all, North American Paleogene cariamiforme fossils are part of this group. Storrs Olson also referred the European '' Elaphrocnemus'' to this clade, though it has since been rejected. Conversely, some analysis have instead recovered them as a polyphyletic group, with '' Bathornis'' and kin being sister taxa to phorusrhacids while ''Paracrax'' is rendered closer to modern seriemas, though this assessment is heavily debated.Mayr, G., & Noriega, J. I. A well-preserved partial skeleton of the poorly known early Miocene seriema ''Noriegavis santacrucensis'' (Aves, Cariamidae). ''Acta palaeontologica Polonica'', 60(3):589-598. The most ... [...More Info...]       [...Related Items...]     OR:     [Wikipedia]   [Google]   [Baidu]   |
|
Eocene
The Eocene ( ) Epoch is a geological epoch (geology), epoch that lasted from about 56 to 33.9 million years ago (mya). It is the second epoch of the Paleogene Period (geology), Period in the modern Cenozoic Era (geology), Era. The name ''Eocene'' comes from the Ancient Greek (''ēṓs'', "dawn") and (''kainós'', "new") and refers to the "dawn" of modern ('new') fauna that appeared during the epoch. The Eocene spans the time from the end of the Paleocene Epoch to the beginning of the Oligocene Epoch. The start of the Eocene is marked by a brief period in which the concentration of the carbon isotope Carbon-13, 13C in the atmosphere was exceptionally low in comparison with the more common isotope Carbon-12, 12C. The end is set at a major extinction event called the ''Grande Coupure'' (the "Great Break" in continuity) or the Eocene–Oligocene extinction event, which may be related to the impact of one or more large bolides in Popigai impact structure, Siberia and in what is now ... [...More Info...]       [...Related Items...]     OR:     [Wikipedia]   [Google]   [Baidu]   |
|
Megafauna
In terrestrial zoology, the megafauna (from Greek μέγας ''megas'' "large" and New Latin ''fauna'' "animal life") comprises the large or giant animals of an area, habitat, or geological period, extinct and/or extant. The most common thresholds used are weight over see page 17 (i.e., having a mass comparable to or larger than a human) or over a tonne, (i.e., having a mass comparable to or larger than an ox). The first of these include many species not popularly thought of as overly large, and being the only few large animals left in a given range/area, such as white-tailed deer, Thomson's gazelle, and red kangaroo. In practice, the most common usage encountered in academic and popular writing describes land mammals roughly larger than a human that are not (solely) domesticated. The term is especially associated with the Pleistocene megafauna – the land animals often larger than their extant counterparts that are considered archetypical of the last ice age, such as mammoth ... [...More Info...]       [...Related Items...]     OR:     [Wikipedia]   [Google]   [Baidu]   |
|
Bird Genera
Birds are a group of warm-blooded vertebrates constituting the class Aves (), characterised by feathers, toothless beaked jaws, the laying of hard-shelled eggs, a high metabolic rate, a four-chambered heart, and a strong yet lightweight skeleton. Birds live worldwide and range in size from the bee hummingbird to the ostrich. There are about ten thousand living species, more than half of which are passerine, or "perching" birds. Birds have whose development varies according to species; the only known groups without wings are the extinct moa and elephant birds. Wings, which are modified forelimbs, gave birds the ability to fly, although further evolution has led to the loss of flight in some birds, including ratites, penguins, and diverse endemic island species. The digestive and respiratory systems of birds are also uniquely adapted for flight. Some bird species of aquatic environments, particularly seabirds and some waterbirds, have further evolved for swimming. Bi ... [...More Info...]       [...Related Items...]     OR:     [Wikipedia]   [Google]   [Baidu]   |
|
Eocene Birds
The Eocene ( ) Epoch is a geological epoch that lasted from about 56 to 33.9 million years ago (mya). It is the second epoch of the Paleogene Period in the modern Cenozoic Era. The name ''Eocene'' comes from the Ancient Greek (''ēṓs'', "dawn") and (''kainós'', "new") and refers to the "dawn" of modern ('new') fauna that appeared during the epoch. The Eocene spans the time from the end of the Paleocene Epoch to the beginning of the Oligocene Epoch. The start of the Eocene is marked by a brief period in which the concentration of the carbon isotope 13C in the atmosphere was exceptionally low in comparison with the more common isotope 12C. The end is set at a major extinction event called the ''Grande Coupure'' (the "Great Break" in continuity) or the Eocene–Oligocene extinction event, which may be related to the impact of one or more large bolides in Siberia and in what is now Chesapeake Bay. As with other geologic periods, the strata that define the start and end of the ... [...More Info...]       [...Related Items...]     OR:     [Wikipedia]   [Google]   [Baidu]   |
|
Geranoididae
Geranoididae is a clade of extinct birds from the early to late Eocene and possibly early Oligocene of North America and Europe. These were mid-sized, long-legged flightless birds.Gerald Mayr (2009). Paleogene Fossil Birds Recent research shows that these birds may actually be palaeognaths related to ostriches. Classification It is rather unambiguous that geranoidids are either part of or stem representatives of Gruoidea, the clade that includes modern cranes, limpkins and trumpeters, though their precise relationship varies among studies, some recovering them as sister taxa to another clade of flightless ratite-like birds, the eogruiids. The most recent consensus appears to be that geranoidids are outside of Gruoidea, with eogruiids being more closely related to modern cranes. However, Mayr (2019) argued that close affinities between Geranoididae and the palaeognathous family Palaeotididae are at least as well supported as the classification of geranoidids into the Gruifo ... [...More Info...]       [...Related Items...]     OR:     [Wikipedia]   [Google]   [Baidu]   |
|
Crane (bird)
Cranes are a family, the Gruidae, of large, long-legged, and long-necked birds in the group Gruiformes. The 15 species of cranes are placed in three genera, ''Antigone'', ''Balearica'', and '' Grus''. Unlike the similar-looking but unrelated herons, cranes fly with necks outstretched, not pulled back. Cranes live on most continents, with the exception of Antarctica and South America. They are opportunistic feeders that change their diets according to the season and their own nutrient requirements. They eat a range of items from small rodents, eggs of birds, fish, amphibians, and insects to grain and berries. Cranes construct platform nests in shallow water, and typically lay two eggs at a time. Both parents help to rear the young, which remain with them until the next breeding season. Some species and populations of cranes migrate over long distances; others do not migrate at all. Cranes are solitary during the breeding season, occurring in pairs, but during the nonbreeding se ... [...More Info...]       [...Related Items...]     OR:     [Wikipedia]   [Google]   [Baidu]   |
|
Bathornis
''Bathornis'' ("tall bird") is an extinct lineage of birds related to modern day seriemas, that lived in North America about 37–20 million years ago. Like the closely related and also extinct phorusrhacids, it was a flightless predator, occupying predatory niches in environments classically considered to be dominated by mammals. It was a highly diverse and successful genus, spanning a large number of species that occurred from the Priabonian Eocene to the Burdigalian Miocene epochs. Description Though most material is highly incomplete, ''Bathornis'' is nonetheless known from a variety of skeletal elements: hindlimbs (most commonly tarso-metatarsals), forelimb elements (especially humeri), pelvises and skulls.Federico L. Agnolin (2009)"Sistemática y Filogenia de las Aves Fororracoideas (Gruiformes, Cariamae)"(PDF). Fundación de Historia Natural Felix de Azara: 1–79. ''Bathornis grallator'' is known from a mostly complete skeleton, including the skull, bearing a proportional ... [...More Info...]       [...Related Items...]     OR:     [Wikipedia]   [Google]   [Baidu]   |
|
Megacerops
''Megacerops'' ("large-horned face", from '' méga-'' "large" + '' kéras'' "horn" + '' ōps'' "face") is an extinct genus of the prehistoric odd-toed ungulate (hoofed mammal) family Brontotheriidae, an extinct group of rhinoceros-like browsers related to horses. It was endemic to North America during the Late Eocene epoch (38–33.9 mya), existing for approximately . Description All of the species had a pair of blunt horns on their snout (the size varying between species), with the horns of males being much larger than those of the females. This could indicate that they were social animals which butted heads for breeding privileges. Despite resembling the rhinoceros, it was larger than any living rhinoceros: the living animal easily approached the size of the African forest elephant, the third-largest land animal today. It stood about tall at the shoulders with an overall length(including tail) of . Its skull reached in greatest length, with some specimens possessing subst ... [...More Info...]       [...Related Items...]     OR:     [Wikipedia]   [Google]   [Baidu]   |
|
Brontothere
Brontotheriidae is a family of extinct mammals belonging to the order Perissodactyla, the order that includes horses, rhinoceroses, and tapirs. Superficially, they looked rather like rhinos, although they were actually more closely related to horses; Equidae and Brontotheriidae make up the suborder Hippomorpha. They lived around 56–34 million years ago, until the very close of the Eocene. Characteristics and evolution Brontotheres retain four toes on their front feet and three toes on their hind feet. Their teeth are adapted to shearing (cutting) relatively nonabrasive vegetation. Their molars have a characteristic W-shaped ectoloph (outer shearing blade). The evolutionary history of this group is well known due to an excellent fossil record in North America. The earliest brontotheres, such as ''Eotitanops'', were rather small, no more than a meter in height, and hornless. Brontotheres evolved massive bodies, although some small species such as ''Nanotitanops'' did pers ... [...More Info...]       [...Related Items...]     OR:     [Wikipedia]   [Google]   [Baidu]   |
|
Seriemas
The seriemas are the sole living members of the small bird family Cariamidae, which is also the only surviving lineage of the order Cariamiformes. Once believed to be related to cranes, they have been placed near the falcons, parrots and passerines, as well as the extinct Phorusrhacidae (terror birds).Hackett, S. J. ''et al''. (2008) A Phylogenomic Study of Birds Reveals Their Evolutionary History. ''Science'' 320(5884):1763–1768 10.1126/science.1157704 The seriemas are large, long-legged territorial birds that range from in length. They live in grasslands, savanna, dry woodland and open forests of Brazil, Bolivia, Argentina, Paraguay and Uruguay. There are two species of seriemas, the red-legged seriema (''Cariama cristata'') and the black-legged seriema (''Chunga burmeisteri'').del Hoyo, J. Elliott, A. & Sargatal, J. (editors). (1996) ''Handbook of the Birds of the World. Volume 3: Hoatzin to Auks''. Lynx Edicions. Names for these birds in the Tupian languages are variously ... [...More Info...]       [...Related Items...]     OR:     [Wikipedia]   [Google]   [Baidu]   |