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Bandicoot
Bandicoots are a group of more than 20 species of small to medium-sized, terrestrial, largely nocturnal marsupial omnivores in the order Peramelemorphia. They are endemic to the Australia–New Guinea region, including the Bismarck Archipelago to the east and Seram and Halmahera to the west. Etymology The bandicoot is a member of the order Peramelemorphia, and the word "bandicoot" is often used informally to refer to any peramelemorph, such as the bilby. The term originally referred to the unrelated Indian bandicoot rat from the Telugu word ''pandikokku'' (పందికొక్కు) wherein ''pandi'' means pig and ''kokku'' means rat. Characteristics Bandicoots have V-shaped faces, ending with their prominent noses similar to proboscides. These noses make them, along with bilbies, similar in appearance to elephant shrews and extinct leptictids, and they are distantly related to both mammal groups. With their well-attuned snouts and sharp claws, bandicoots are ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Eastern Barred Bandicoot
The eastern barred bandicoot (''Perameles gunnii'') is a nocturnal, rabbit-sized marsupial endemic to southeastern Australia, being native to the island of Tasmania and mainland Victoria (Australia), Victoria. It is one of three surviving bandicoot species in the genus ''Perameles''. It is distinguishable from its partially-sympatric congener – the long-nosed bandicoot – via three or four dark horizontal bars found on its rump. In Tasmania, it is relatively abundant. The mainland population in Victoria is struggling and is subject to ongoing conservation endeavors. Description The eastern barred bandicoot weighs less than and has a short tail and three to four whitish bars across the rump. The eastern barred bandicoot has two separated populations, one on the mainland of Australia and one on the island of Tasmania. The Tasmanian form is somewhat larger than the mainland form as the average adult mass is 750 g in Victoria and 1,000 g in Tasmania. It lives for just two ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Peramelemorphia
The order Peramelemorphia includes the bandicoots and bilbies. All members of the order are endemic to Australia-New Guinea and most have the characteristic bandicoot shape: a plump, arch-backed body with a long, delicately tapering snout, very large upright ears, relatively long, thin legs, and a thin tail. Their size varies from about 140 grams up to 4 kilograms, but most species are about one kilogram. Phylogeny Placement within Marsupialia The position of the Peramelemorphia within the marsupial family tree has long been puzzling and controversial. There are two morphological features in the order that appear to show a clear evolutionary link with another marsupial group: the type of foot, and the teeth. Unfortunately, these clear signposts point in opposite directions. All members of the order are polyprotodont (have several pairs of lower front teeth)—in the case of the Peramelemorphia, three pairs. This suggests that they have evolved within Dasyuromorphia (mar ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Marsupial Penis
Marsupials are a diverse group of mammals belonging to the infraclass Marsupialia. They are natively found in Australasia, Wallacea, and the Americas. One of marsupials' unique features is their reproductive strategy: the young are born in a relatively undeveloped state and then nurtured within a pouch on their mother's abdomen. Extant marsupials encompass many species, including kangaroos, koalas, opossums, possums, Tasmanian devils, wombats, wallabies, and bandicoots. Marsupials constitute a clade stemming from the last common ancestor of extant Metatheria, which encompasses all mammals more closely related to marsupials than to placentals. The evolutionary split between placentals and marsupials occurred 125-160 million years ago, in the Middle Jurassic-Early Cretaceous period. Presently, close to 70% of the 334 extant marsupial species are concentrated on the Australian continent, including mainland Australia, Tasmania, New Guinea, and nearby islands. The remaini ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Marsupial
Marsupials are a diverse group of mammals belonging to the infraclass Marsupialia. They are natively found in Australasia, Wallacea, and the Americas. One of marsupials' unique features is their reproductive strategy: the young are born in a relatively undeveloped state and then nurtured within a pouch on their mother's abdomen. Extant marsupials encompass many species, including Kangaroo, kangaroos, Koala, koalas, Opossum, opossums, Phalangeriformes, possums, Tasmanian devil, Tasmanian devils, Wombat, wombats, Wallaby, wallabies, and Bandicoot, bandicoots. Marsupials constitute a clade stemming from the last common ancestor of extant Metatheria, which encompasses all mammals more closely related to marsupials than to Placentalia, placentals. The evolutionary split between placentals and marsupials occurred 125-160 million years ago, in the Middle Jurassic-Early Cretaceous period. Presently, close to 70% of the 334 extant marsupial species are concentrated on the Australian ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Bandicota
''Bandicota'' is a genus of rodents from Asia known as the bandicoot rats. Their common name and genus name are derived from the Telugu language word ''pandikokku'' (పందికొక్కు). DNA studies have found the group to be a monophyletic clade sister to the radiation of Maluku Islands, Molucca and Australian ''Rattus'' species as part of the Paraphyly, paraphyletic ''Rattus'' ''sensu lato''. Species *Greater bandicoot rat (''B. indica'') Bechstein, 1800 *Lesser bandicoot rat (''B. bengalensis'') Gray and Hardwicke, 1833 *Savile's bandicoot rat (''B. savilei'') Thomas, 1916 References Bandicota, Rodent genera Taxa named by John Edward Gray {{Murinae-stub ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Late Oligocene
The Chattian is, in the geologic timescale The geologic time scale or geological time scale (GTS) is a representation of time based on the rock record of Earth. It is a system of chronological dating that uses chronostratigraphy (the process of relating strata to time) and geochron ..., the younger of two age (geology), ages or upper of two stage (stratigraphy), stages of the Oligocene epoch (geology), Epoch/Series (stratigraphy), Series. It spans the time between . The Chattian is preceded by the Rupelian and is followed by the Aquitanian (stage), Aquitanian (the lowest stage of the Miocene). Stratigraphic definition The Chattian was introduced by Austrian palaeontologist Theodor Fuchs in 1894. Fuchs named the stage after the Chatti, a Germanic peoples, Germanic tribe.Berry, Edward W"The Mayence Basin, a Chapter of Geologic History" ''The Scientific Monthly'', Vol. 16, No. 2, February 1923. pp. 114. Retrieved March 18, 2020. The original type locality (geology), type l ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Chorioallantoic Placenta
The placenta (: placentas or placentae) is a temporary embryonic and later fetal organ that begins developing from the blastocyst shortly after implantation. It plays critical roles in facilitating nutrient, gas, and waste exchange between the physically separate maternal and fetal circulations, and is an important endocrine organ, producing hormones that regulate both maternal and fetal physiology during pregnancy. The placenta connects to the fetus via the umbilical cord, and on the opposite aspect to the maternal uterus in a species-dependent manner. In humans, a thin layer of maternal decidual (endometrial) tissue comes away with the placenta when it is expelled from the uterus following birth (sometimes incorrectly referred to as the 'maternal part' of the placenta). Placentas are a defining characteristic of placental mammals, but are also found in marsupials and some non-mammals with varying levels of development. Mammalian placentas probably first evolved about 150 m ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Leptictida
Leptictida (''leptos iktis'' "small/slender weasel") is a possibly paraphyletic extinct order of eutherian mammals. Their classification is contentious: according to cladistic studies, they may be (distantly) related to Euarchontoglires (rodents, primates and their relatives), although they are more recently regarded as the first branch to split from basal eutherians. One recent large-scale cladistic analysis of eutherian mammals favored lepictidans as close to the placental crown-clade; and several other recent analyses that included data from Cretaceous non-eutherian mammals found ''Leptictis'' to belong to the superorder Afrotheria. The most recent phylogenetic studies recover it as actually a paraphyletic assemblage leading to Placentalia. Description The leptictids are a characteristic example of the non-specialized placental mammals that took part in the late Cretaceous-Paleocene evolutionary radiation, originally bunched together in the order Insectivora. The leptictids ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Fossorial
A fossorial animal () is one that is adapted to digging and which lives primarily (but not solely) underground. Examples of fossorial vertebrates are Mole (animal), moles, badgers, naked mole-rats, meerkats, armadillos, wombats, and mole salamanders. Among invertebrates, many molluscs (e.g., clams), insects (e.g., beetles, wasps, bees), and arachnids (e.g. spiders) are fossorial. Prehistoric evidence The physical adaptation of fossoriality is widely accepted as being widespread among many Prehistory, prehistoric Phylum, phyla and Taxon, taxa, such as bacteria and early eukaryotes. Furthermore, fossoriality has evolved independently multiple times, even within a single Family (biology), family. Fossorial animals appeared simultaneously with the colonization of land by arthropods in the late Ordovician period (over 440 million years ago). Other notable early burrowers include ''Eocaecilia'' and possibly ''Dinilysia''. The oldest example of burrowing in synapsids, the lineag ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Embryo
An embryo ( ) is the initial stage of development for a multicellular organism. In organisms that reproduce sexually, embryonic development is the part of the life cycle that begins just after fertilization of the female egg cell by the male sperm cell. The resulting fusion of these two cells produces a single-celled zygote that undergoes many cell divisions that produce cells known as blastomeres. The blastomeres (4-cell stage) are arranged as a solid ball that when reaching a certain size, called a morula, (16-cell stage) takes in fluid to create a cavity called a blastocoel. The structure is then termed a blastula, or a blastocyst in mammals. The mammalian blastocyst hatches before implantating into the endometrial lining of the womb. Once implanted the embryo will continue its development through the next stages of gastrulation, neurulation, and organogenesis. Gastrulation is the formation of the three germ layers that will form all of the different parts of t ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Choriovitelline Placenta
A choriovitelline placenta is a placenta formed by the yolk sac and chorion. In a choriovitelline placenta, the yolk sac fuses with the chorion and, subsequently, wrinkles develop that hold the embryo to the uterine wall, thus forming the choriovitelline placenta. The chorionic blood vessels are connected with the vitelline blood vessel of the yolk sac. Because the yolk sac is formed earlier than the allantois in embryo development, a choriovitelline placenta can form earlier than the chorioallantoic placenta. All marsupials maintain a choriovitelline placenta. (However, bandicoots also have a chorioallantoic placenta The placenta (: placentas or placentae) is a temporary embryonic and later fetal organ that begins developing from the blastocyst shortly after implantation. It plays critical roles in facilitating nutrient, gas, and waste exchange between th ....) Primates do not form any choriovitelline placenta. However, this is not to say the existence of a choriovitelline p ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Uterine
The uterus (from Latin ''uterus'', : uteri or uteruses) or womb () is the organ in the reproductive system of most female mammals, including humans, that accommodates the embryonic and fetal development of one or more fertilized eggs until birth. The uterus is a hormone-responsive sex organ that contains glands in its lining that secrete uterine milk for embryonic nourishment. (The term ''uterus'' is also applied to analogous structures in some non-mammalian animals.) In humans, the lower end of the uterus is a narrow part known as the isthmus that connects to the cervix, the anterior gateway leading to the vagina. The upper end, the body of the uterus, is connected to the fallopian tubes at the uterine horns; the rounded part, the fundus, is above the openings to the fallopian tubes. The connection of the uterine cavity with a fallopian tube is called the uterotubal junction. The zygote, fertilized egg is carried to the uterus along the fallopian tube. It will have Cleavage ( ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
