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Aegyptonycteris
''Aegyptonycteris'' ("Egyptian bat") is a genus of extinct bat from the Late Eocene of North Africa. It is currently known from a single specimen (holotype CGM 83740) from the Birket Qarun Formation in the Fayum Depression in western Egypt. ''Aegyptonycteris'' is notable both its large size, comparable to the larger modern bat species, as well due to its omnivorous diet, as opposed to the mostly insectivorous diets of other Eocene bats (and the majority of modern species). This makes it a remarkable example of early chiropteran speciation, having not only attained a rather large size but also specialised towards a drastically different ecological niche from its contemporaries. Description ''Aegyptonycteris'' is currently known only from its holotype. Said specimen is composed of a right maxilla - including the posterior portion of the orbital door and base of the zygomatic arch - and two molar teeth. The anterior orbital door is broad and flat and the zygomatic arch is robust a ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Witwatia
''Witwatia'' (from the Egyptian Arabic ''Wit Wat'' meaning "large, flapping wings") is an extinct genus of giant bat that contained two species which lived in the Al Fayyum in Egypt during the late Eocene (Priabonian epoch) and one species which lived in Tunisia during the early Eocene. It is known from a lower jaw and teeth. Three species have been named: the type species ''W. schlosseri'', ''W. eremicus'' and ''W. sigei''. Ecology These were large-sized carnivorous bats, possessing large canines, robust jaws and slicing molars. Opportunistic frugivory has been suggested, but since rejected.Nancy B. Simmons; Erik R. Seiffert; Gregg F. Gunnell (2016). "A New Family of Large Omnivorous Bats (Mammalia, Chiroptera) from the Late Eocene of the Fayum Depression, Egypt, with Comments on Use of the Name “Eochiroptera”". ''American Museum Novitates'' 3857: 1–43. doi:10.1206/3857.1. The largest forms such as ''Witwatia schlosseri'' were comparable in size and possibly ecology to ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Priabonian
The Priabonian is, in the ICS's geologic timescale, the latest age or the upper stage of the Eocene Epoch or Series. It spans the time between . The Priabonian is preceded by the Bartonian and is followed by the Rupelian, the lowest stage of the Oligocene. '' Priabona'', an extinct dipteran of Pipunculidae family, is named after Priabonian, the age of deposits from which this insect is known. History and naming The Priabonian Stage was introduced in scientific literature by Ernest Munier-Chalmas and Albert de Lapparent in 1893. The stage is named after the small hamlet of Priabona in the community of Monte di Malo, in the Veneto region of northern Italy. Stratigraphic definition The base of the Priabonian Stage is at the first appearance of calcareous nannoplankton species '' Chiasmolithus oamaruensis'' (which forms the base of nanoplankton biozone NP18). An official GSSP was ratified in 2020, and was placed in the Alano di Piave section in Alano di Piave, Bellu ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Animal Echolocation
Echolocation, also called bio sonar, is a biological active sonar used by several animal groups, both in the air and underwater. Echolocating animals emit calls and listen to the Echo (phenomenon) , echoes of those calls that return from various objects near them. They use these echoes to locate and identify the objects. Echolocation is used for animal navigation , navigation, foraging, and predation, hunting prey. Echolocation calls can be Frequency modulation, frequency modulated (FM, varying in pitch during the call) or constant frequency (CF). FM offers precise range discrimination to localize the prey, at the cost of reduced operational range. CF allows both the prey's velocity and its movements to be detected by means of the Doppler effect. FM may be best for close, cluttered environments, while CF may be better in open environments or for hunting while perched. Echolocating animals include mammals, especially odontocetes (toothed whales) and some bat species, and, using s ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Gigantism
Gigantism (, ''gígas'', "wiktionary:giant, giant", plural γίγαντες, ''gígantes''), also known as giantism, is a condition characterized by excessive growth and height significantly above average height, average. In humans, this condition is caused by over-production of growth hormone in childhood. It is a rare disorder resulting from increased levels of growth hormone before the fusion of the Epiphyseal plate, growth plate which usually occurs at some point soon after puberty. This increase is most often due to abnormal tumor growths on the pituitary gland. Gigantism should not be confused with acromegaly, the adult form of the disorder, characterized by Somatic (biology), somatic enlargement specifically in the extremities and face. Cause Gigantism is characterized by an excess of growth hormone (GH). The excess of growth hormone that brings about gigantism is virtually always caused by pituitary growths (adenomas). These adenomas are on the Anterior pituitary, anteri ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Hyaenodonta
Hyaenodonta (" hyena teeth") is an extinct order of hypercarnivorous placental mammals of clade Pan-Carnivora from mirorder Ferae. Hyaenodonts were important mammalian predators that arose during the early Paleocene in Europe and persisted well into the late Miocene. Characteristics Hyaenodonts are characterized by long, often disproportionately large skulls, slender jaws, and slim bodies. They generally ranged in size from 30 to 140 cm at the shoulder. While '' Simbakubwa kutokaafrika'' may have been up to (surpassing the modern polar bear in size), this estimate is suspect due to being based on skull-body size ratios derived from felids, which have much smaller skulls for their body size. Other large hyaenodonts include two close and later-surviving relatives of ''Simbakubwa'', '' Hyainailouros'' and '' Megistotherium'' (the latter likely being the largest in the group), and the much earlier-living '' Hyaenodon gigas'' (the largest species from genus '' Hyaenodo ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Embrithopod
Embrithopoda ("heavy-footed") is an order of extinct mammals known from Asia, Africa and Eastern Europe. Most of the embrithopod genera are known exclusively from jaws and teeth dated from the late Paleocene to the late Eocene; however, the order is best known from its terminal member, the elephantine '' Arsinoitherium''. Description While embrithopods bore a superficial resemblance to rhinoceroses, their horns had bony cores covered in keratinized skin. Not all embrithopods possessed horns, either. Despite their appearance, they have been regarded as related to elephants, not perissodactyls. As tethytheres, the Embrithopoda have been believed to be part of the clade Afrotheria. However, a study of the basal arsinoitheriid, ''Palaeoamasia'', suggests that embrithopods are not tethytheres or even paenungulates, and that they need to be better sampled in an analysis of eutherian relationships to clarify if they are even afrotherians.[Erdal et al.'s inclusion of Embrithopoda in ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Elephants
Elephants are the Largest and heaviest animals, largest living land animals. Three living species are currently recognised: the African bush elephant (''Loxodonta africana''), the African forest elephant (''L. cyclotis''), and the Asian elephant (''Elephas maximus''). They are the only surviving members of the Family (biology), family Elephantidae and the Order (biology), order Proboscidea; extinct relatives include mammoths and mastodons. Distinctive features of elephants include a long proboscis called a trunk, tusks, large ear flaps, pillar-like legs, and tough but sensitive grey skin. The trunk is Prehensility, prehensile, bringing food and water to the mouth and grasping objects. Tusks, which are derived from the incisor teeth, serve both as weapons and as tools for moving objects and digging. The large ear flaps assist in maintaining a constant body temperature as well as in communication. African elephants have larger ears and concave backs, whereas Asian elephants hav ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Basilosaurus
''Basilosaurus'' (meaning "king lizard") is a genus of large, predatory, prehistoric archaeocete whale from the late Eocene, approximately 41.3 to 33.9 million years ago (mya). First described in 1834, it was the first archaeocete and prehistoric whale known to science. Fossils attributed to the type species ''B. cetoides'' were discovered in the southeastern United States. They were originally thought to be of a giant reptile, hence the suffix "-saurus", Ancient Greek for "lizard". The animal was later found to be an early marine mammal, prompting attempts at renaming the creature, which failed as the rules of zoological nomenclature dictate using the original name given. The second species named in 1904, ''B. isis'', lived in the region currently known as the Mediterranean Sea, with fossils found in North Africa and Jordan. ''Basilosaurus'' is thought to have been one of the largest animals of the Paleogene, with the type species ''B. cetoides'' measuring around long and we ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Lagoons
A lagoon is a shallow body of water separated from a larger body of water by a narrow landform, such as reefs, barrier islands, barrier peninsulas, or isthmuses. Lagoons are commonly divided into '' coastal lagoons'' (or ''barrier lagoons'') and ''atoll lagoons''. They have also been identified as occurring on mixed-sand and gravel coastlines. There is an overlap between bodies of water classified as coastal lagoons and bodies of water classified as estuaries. Lagoons are common coastal features around many parts of the world. Definition and terminology Lagoons are shallow, often elongated bodies of water separated from a larger body of water by a shallow or exposed shoal, coral reef, or similar feature. Some authorities include fresh water bodies in the definition of "lagoon", while others explicitly restrict "lagoon" to bodies of water with some degree of salinity. The distinction between "lagoon" and "estuary" also varies between authorities. Richard A. Davis Jr. restricts " ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Tropical
The tropics are the regions of Earth surrounding the equator, where the sun may shine directly overhead. This contrasts with the temperate or polar regions of Earth, where the Sun can never be directly overhead. This is because of Earth's axial tilt; the width of the tropics (in latitude) is twice the tilt. The tropics are also referred to as the tropical zone and the torrid zone (see geographical zone). Due to the overhead sun, the tropics receive the most solar energy over the course of the year, and consequently have the highest temperatures on the planet. Even when not directly overhead, the sun is still close to overhead throughout the year, therefore the tropics also have the lowest seasonal variation on the planet; "winter" and "summer" lose their temperature contrast. Instead, seasons are more commonly divided by precipitation variations than by temperature variations. The tropics maintain wide diversity of local climates, such as rain forests, monsoons, sa ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Eocene
The Eocene ( ) is a geological epoch (geology), epoch that lasted from about 56 to 33.9 million years ago (Ma). 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'', 'Eos, Dawn') and (''kainós'', "new") and refers to the "dawn" of modern ('new') fauna that appeared during the epoch.See: *Letter from William Whewell to Charles Lyell dated 31 January 1831 in: * From p. 55: "The period next antecedent we shall call Eocene, from ήως, aurora, and χαινος, recens, because the extremely small proportion of living species contained in these strata, indicates what may be considered the first commencement, or ''dawn'', of the existing state of the animate creation." 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 isoto ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Nectarivory
In zoology, a nectarivore is an animal which derives its energy and nutrient requirements from a diet consisting mainly or exclusively of the sugar-rich nectar produced by flowering plants. Nectar as a food source presents a number of benefits as well as challenges. It is essentially a solution of (as much as 80%) the simple sugars sucrose, glucose and fructose, which are easily ingested and digested, representing a rich and efficient source of nutrition. This solution is often diluted either by the plant that produces it or by rain falling on a flower and many nectarivores possess adaptations to effectively rid themselves of any excess water ingested this way. However, nectar is an incomplete source of nutrition. While it does contain proteins and amino acids, these are found in low quantities, and it is severely deficient in minerals and vitamins. Very few organisms consume nectar exclusively over their whole life cycle, either supplementing it with other sources, particularl ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
