|
Uranotheria
Paenungulata (from Latin ''paene'' "almost" + ''ungulātus'' "having hoofs") is a clade of "sub-ungulates", which groups three extant mammal orders: Proboscidea (including elephants), Sirenia ( sea cows, including dugongs and manatees), and Hyracoidea (hyraxes). At least two more possible orders are known only as fossils, namely Embrithopoda and Desmostylia. Molecular evidence indicates that Paenungulata (or at least its extant members) is part of the cohort Afrotheria, an ancient assemblage of mainly African mammals of great diversity. The other members of this cohort are the orders Afrosoricida (tenrecs and golden moles), Macroscelidea (elephant shrews) and Tubulidentata (aardvarks). Of the five orders, hyraxes are the most basal, followed by embrithopods; the remaining orders (sirenians and elephants) are more closely related. These latter three are grouped as the Tethytheria, because it is believed that their common ancestors lived on the shores of the prehistoric Tethys Sea ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Paleocene
The Paleocene ( ), or Palaeocene, is a geological epoch (geology), epoch that lasted from about 66 to 56 mya (unit), million years ago (mya). It is the first epoch of the Paleogene Period (geology), Period in the modern Cenozoic Era (geology), Era. The name is a combination of the Ancient Greek ''palaiós'' meaning "old" and the Eocene Epoch (which succeeds the Paleocene), translating to "the old part of the Eocene". The epoch is bracketed by two major events in Earth's history. The K–Pg extinction event, brought on by an asteroid impact (Chicxulub impact) and possibly volcanism (Deccan Traps), marked the beginning of the Paleocene and killed off 75% of species, most famously the non-avian dinosaurs. The end of the epoch was marked by the Paleocene–Eocene Thermal Maximum (PETM), which was a major climatic event wherein about 2,500–4,500 gigatons of carbon were released into the atmosphere and ocean systems, causing a spike in global temperatures and ocean acidification. ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Mammal
A mammal () is a vertebrate animal of the Class (biology), class Mammalia (). Mammals are characterised by the presence of milk-producing mammary glands for feeding their young, a broad neocortex region of the brain, fur or hair, and three Evolution of mammalian auditory ossicles, middle ear bones. These characteristics distinguish them from reptiles and birds, from which their ancestors Genetic divergence, diverged in the Carboniferous Period over 300 million years ago. Around 6,640 Neontology#Extant taxon, extant species of mammals have been described and divided into 27 Order (biology), orders. The study of mammals is called mammalogy. The largest orders of mammals, by number of species, are the rodents, bats, and eulipotyphlans (including hedgehogs, Mole (animal), moles and shrews). The next three are the primates (including humans, monkeys and lemurs), the Artiodactyl, even-toed ungulates (including pigs, camels, and whales), and the Carnivora (including Felidae, ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Elephant Shrew
Elephant shrews, also called jumping shrews or sengis, are small insectivore, insectivorous mammals native to Africa, belonging to the family Macroscelididae, in the order (biology), order Macroscelidea. Their traditional common English name "elephant shrew" comes from a perceived resemblance between their long noses and the trunk of an elephant, and their superficial similarity with shrews (family Soricidae) in the order Eulipotyphla. However, Phylogenetics, phylogenetic analysis has revealed that elephant shrews are not properly classified with true shrews, but are in fact more closely related to elephants than to shrews. In 1997, the biologist Jonathan Kingdon proposed that they instead be called "sengis" (singular ''sengi''), a term derived from the Bantu languages of Africa, and in 1998, they were classified into the new clade Afrotheria. They are widely distributed across the southern part of Africa, and although common nowhere, can be found in almost any type of habitat, ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Golden Mole
Golden moles are small insectivorous burrowing mammals endemic to Sub-Saharan Africa. They comprise the family Chrysochloridae (the only family in the suborder Chrysochloridea) and as such they are taxonomically distinct from the true moles, family Talpidae, and other mole-like families, all of which, to various degrees, they resemble as a result of evolutionary convergence. There are 21 species. Some (e.g., ''Chrysochloris asiatica'', ''Amblysomus hottentotus'') are relatively common, whereas others (e.g., species of ''Chrysospalax'', ''Cryptochloris'', ''Neamblysomus'') are rare and endangered. Taxonomy Despite their extreme evolutionary convergence with moles, their closest relatives are the otter shrews and tenrecs. They are more distantly related to other insectivorous African mammals such as aardvarks and elephant shrews, and even more distantly related to elephants and sirenians. Characteristics and affinities Like most burrowing mammals with similar habits, the ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Tenrec
A tenrec () is a mammal belonging to any species within the afrotherian family Tenrecidae, which is endemic to Madagascar. Tenrecs are a very diverse group, as a result of adaptive radiation, and exhibit convergent evolution, some resemble hedgehogs, shrews, opossums, rats, and mice. They occupy aquatic, arboreal, terrestrial, and fossorial environments. Some of these species, including the greater hedgehog tenrec, can be found in the Madagascar dry deciduous forests. However, the speciation rate in this group has been higher in humid forests. All tenrecs are believed to descend from a common ancestor that lived 29–37 million years ago after rafting over from Africa. The split from their closest relatives, African otter shrews, is estimated to have occurred about 47–53 million years ago. Etymology The word "tenrec" is borrowed, via French, from the Malagasy word (variant of ), which refers to the tailless tenrec (''Tenrec ecaudatus''); the Malagasy word may be ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Afrosoricida
The clade Afrosoricida (a Latin-Greek compound name which means "looking like African shrews") contains the golden moles of Southern Africa, the otter shrews of equatorial Africa and the tenrecs of Madagascar. These three groups of small mammals were for most of the 19th and 20th centuries regarded as a part of the Insectivora or Lipotyphla, but both of those groups, as traditionally used, are polyphyletic. Naming Some biologists use Tenrecoidea or Tenrecomorpha as the name for the tenrec-golden mole clade and regard Afrosoricida as a junior synonym (even though the rules of the ICZN do not apply above the Linnean rank of family). This is based on the principles of Simpson, summarized by Asher & Helgen to mean that "priority and stability should comprise the overriding principles by which new, high-level taxa are named. Established names for any given clade should not be altered unless the name with precedent unambiguously threatens stability." When "Afrosoricida" was first nam ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Africa
Africa is the world's second-largest and second-most populous continent after Asia. At about 30.3 million km2 (11.7 million square miles) including adjacent islands, it covers 20% of Earth's land area and 6% of its total surface area.Sayre, April Pulley (1999), ''Africa'', Twenty-First Century Books. . With nearly billion people as of , it accounts for about of the world's human population. Demographics of Africa, Africa's population is the youngest among all the continents; the median age in 2012 was 19.7, when the worldwide median age was 30.4. Based on 2024 projections, Africa's population will exceed 3.8 billion people by 2100. Africa is the least wealthy inhabited continent per capita and second-least wealthy by total wealth, ahead of Oceania. Scholars have attributed this to different factors including Geography of Africa, geography, Climate of Africa, climate, corruption, Scramble for Africa, colonialism, the Cold War, and neocolonialism. Despite this lo ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Afrotheria
Afrotheria ( from Latin ''Afro-'' "of Africa" + ''theria'' "wild beast") is a superorder of placental mammals, the living members of which belong to groups that are either currently living in Africa or of African origin: golden moles, elephant shrews (also known as sengis), otter shrews, tenrecs, aardvarks, hyraxes, elephants, sea cows, and several extinct clades. Most groups of afrotheres share little or no superficial resemblance, and their similarities have only become known in recent times due to genetics and molecular studies. Many afrothere groups are found mostly or exclusively in Africa, reflecting the fact that Africa was an island continent from the Cretaceous until the early Miocene around 20 million years ago, when Afro-Arabia collided with Eurasia. Because Africa was isolated by water, Laurasian groups of mammals such as insectivores, rodents, lagomorphs, carnivorans and ungulates could not reach Africa for much of the early to mid-Cenozoic. Instead, the ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Desmostylia
The Desmostylia (from Greek δεσμά ''desma'', "bundle", and στῦλος ''stylos'', "pillar") are an extinct order of aquatic mammals native to the North Pacific from the early Oligocene (Rupelian) to the late Miocene (Tortonian) (). Desmostylians are the only known extinct order of marine mammals. The Desmostylia, together with Sirenia and Proboscidea (and possibly Embrithopoda), have traditionally been assigned to the afrotherian clade Tethytheria, a group named after the paleoocean Tethys around which they originally evolved. The relationship between the Desmostylia and the other orders within the Tethytheria has been disputed; if the common ancestor of all tethytheres was semiaquatic, the Proboscidea became secondarily terrestrial; alternatively, the Desmostylia and Sirenia could have evolved independently into aquatic mammals. The assignment of Desmostylia to Afrotheria has always been problematic from a biogeographic standpoint, given that Africa was the locus of the ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Hyrax
Hyraxes (), also called dassies, are small, stout, thickset, herbivorous mammals in the family Procaviidae within the order Hyracoidea. Hyraxes are well-furred, rotund animals with short tails. Modern hyraxes are typically between in length and weigh between . They are superficially similar to marmots or over-large pikas but are much more closely related to elephants and sirenians. Hyraxes have a life span of 9 to 14 years. Both types of "rock" hyrax ( ''P. capensis'' and ''H. brucei'') live on rock outcrops, including cliffs in Ethiopia and isolated granite outcrops called koppies in southern Africa. Almost all hyraxes are limited to Africa; the exception is the rock hyrax (''P. capensis'') which is also found in adjacent parts of the Middle East. Hyraxes were a much more diverse group in the past encompassing species considerably larger than modern hyraxes. The largest known extinct hyrax, '' Titanohyrax ultimus'', has been estimated to weigh , comp ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Manatee
Manatees (, family (biology), family Trichechidae, genus ''Trichechus'') are large, fully aquatic, mostly herbivory, herbivorous marine mammals sometimes known as sea cows. There are three accepted living species of Trichechidae, representing three of the four living species in the order Sirenia: the Amazonian manatee (''Trichechus inunguis''), the West Indian manatee (''Trichechus manatus''), and the West African manatee (''Trichechus senegalensis''). They measure up to long, weigh as much as , and have paddle-like tails. Manatees are Herbivory, herbivores and eat over 60 different freshwater and saltwater plants. Manatees inhabit the shallow, marshy coastal areas and rivers of the Caribbean Sea, the Gulf of Mexico, the Amazon basin, and West Africa. The main causes of death for manatees are human-related issues, such as habitat destruction and human objects. Their slow-moving, curious nature has led to violent collisions with propeller-driven boats and ships. Some manatees h ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Dugong
The dugong (; ''Dugong dugon'') is a marine mammal. It is one of four living species of the order Sirenia, which also includes three species of manatees. It is the only living representative of the once-diverse family Dugongidae; its closest modern relative, Steller's sea cow (''Hydrodamalis gigas''), was hunted to extinction in the 18th century. The dugong is the only sirenian in its range, which spans the waters of some 40 countries and territories throughout the Indo-West Pacific. The dugong is largely dependent on seagrass communities for subsistence and is thus restricted to the coastal habitats that support seagrass meadows, with the largest dugong concentrations typically occurring in wide, shallow, protected areas such as bays, mangrove channels, the waters of large inshore islands, and inter-reefal waters. The northern waters of Australia between Shark Bay and Moreton Bay are believed to be the dugong's contemporary stronghold. Like all modern sirenians, the d ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
