|
Mephitid
Mephitidae is a family of mammals comprising the skunks and stink badgers. They are noted for the great development of their anal scent glands, which they use to deter predators. Skunks were formerly classified as a subfamily of the Mustelidae (the weasel family); however, in the 1990s, genetic evidence caused skunks to be treated as a separate family. Similarly, the stink badgers had been classified with badgers, but genetic evidence shows they share a more recent common ancestor with skunks, so they are now included in the skunk family. A 2017 study using retroposon markers indicated that they are most closely related to the Ailuridae (red pandas and allies) and Procyonidae (raccoons and allies). There are twelve extant species of mephitids in four genera: ''Conepatus'' (hog-nosed skunks, four species); '' Mephitis'' (the hooded and striped skunks, two species); ''Mydaus'' (stink badgers, two species); and ''Spilogale'' (spotted skunks, four species). The two stink badgers in ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Palaeomephitis
''Palaeomephitis steinheimensis'' is an extinct species of musteloid, possibly a mephitid (skunk), from the Miocene epoch of Europe. Description ''Palaeomephitis steinheimensis'' was described by Jäger in 1839 from a well-preserved cranium found in Steinheim am Albuch in Baden-Württemberg, southern Germany. Subsequently, different authors considered it to represent a viverrid or a leptarctine mustelid. It was placed in the Mephitinae (now considered to be a distinct family) by Wolsan in 1999, on the evidence of its having an extended epitympanic recess to the middle ear. However, Geraads and Spassov (2016) were uncertain it in fact had this expanded recess, since that area of the skull is imperfectly preserved. Due to this and other factors, such as it differing from Mephitidae in some characters, these authors considered the mephitid affinities of ''Palaeomephitis'' doubtful. Taxonomy In its traditional skunk classification, ''Palaeomephitis'' is considered to stand close ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Spotted Skunk
The genus ''Spilogale'' includes all skunks commonly known as spotted skunks. Currently, there are four accepted extant species: ''S. gracilis'', ''S. putorius'', ''S. pygmaea'', and ''S. angustifrons''. New research, however, proposes that there may be up to seven. Extant species In the past, anywhere between two and fourteen species of ''Spilogale'' have been recognized, but today most authorities accept a four species model (seen below). A 2021 DNA analysis of 203 specimens from across their known range suggests that there may be as many as seven distinct species in the genus, some cryptic. Description Mammalogists consider ''S. gracilis'' and ''S. putorius'' different species because of differences in reproductive patterns, reproductive morphology, and chromosomal variation. However, interbreeding has never been disproved. The name ''Spilogale'' comes from the Greek word ''spilo'', which means "spotted", and gale, which means "weasel". ''Putorius'' is the Latin word for " ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Promephitis
''Promephitis'' is an extinct genus of mephitid, of which several species have been described from the Miocene and early Pliocene of Europe and Asia. Characteristics The fossil remains of the ''Promephitis'' species, like all members of the skunk family (Mephitidae), have a significant extension of epitympanic recess, a chamber of the middle ear, into the region of mastoid and squamous parts of the temporal bones. This extension is recognizable as an inflated bulge on the lateral wall of the skull over the mastoid. In addition, skunks have specific characteristics of the teeth, especially the molars, which distinguish them from other carnivora. The genus ''Promephitis'' also shows a distinctive structure of the premolar tooth P4 as well as a very small P2, through which they are distinguishable from other genera. Distribution and temporal classification Species of ''Promephitis'' ranged widely in Eurasia, and fossils have been found both in Europe and in Asia. They are clas ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Spilogale
The genus ''Spilogale'' includes all skunks commonly known as spotted skunks. Currently, there are four accepted extant species: ''S. gracilis'', ''S. putorius'', ''S. pygmaea'', and ''S. angustifrons''. New research, however, proposes that there may be up to seven. Extant species In the past, anywhere between two and fourteen species of ''Spilogale'' have been recognized, but today most authorities accept a four species model (seen below). A 2021 DNA analysis of 203 specimens from across their known range suggests that there may be as many as seven distinct species in the genus, some cryptic. Description Mammalogists consider ''S. gracilis'' and ''S. putorius'' different species because of differences in reproductive patterns, reproductive morphology, and chromosomal variation. However, interbreeding has never been disproved. The name ''Spilogale'' comes from the Greek word ''spilo'', which means "spotted", and gale, which means "weasel". ''Putorius'' is the Latin word for " ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Skunk
Skunks are mammals in the family Mephitidae. They are known for their ability to spray a liquid with a strong, unpleasant scent from their anal glands. Different species of skunk vary in appearance from black-and-white to brown, cream or ginger colored, but all have warning coloration. While related to polecats and other members of the weasel family, skunks have as their closest relatives the Old World stink badgers. Taxonomy In alphabetical order, the living species of skunks are: * Family Mephitidae ** Genus: '' Conepatus'' *** ''Conepatus chinga'' – Molina's hog-nosed skunk *** ''Conepatus humboldtii'' – Humboldt's hog-nosed skunk *** ''Conepatus leuconotus'' – American hog-nosed skunk *** ''Conepatus semistriatus'' – striped hog-nosed skunk ** Genus: '' Mephitis'' *** ''Mephitis macroura'' – hooded skunk *** ''Mephitis mephitis'' – striped skunk ** Genus: '' Spilogale'' *** ''Spilogale angustifrons'' – southern spotted skunk *** ''Spilogale gr ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Middle Miocene
The Middle Miocene is a sub-epoch of the Miocene epoch (geology), epoch made up of two Stage (stratigraphy), stages: the Langhian and Serravallian stages. The Middle Miocene is preceded by the Early Miocene. The sub-epoch lasted from 15.97 ± 0.05 Ma (million years ago) to 11.608 ± 0.005 Ma. During this period, a sharp drop in global temperatures took place. This event is known as the Middle Miocene disruption, Middle Miocene Climatic Transition. For the purpose of establishing European land mammal ages, this sub-epoch is equivalent to the Astaracian age. References External links GeoWhen Database - Middle Miocene Miocene, .02 Miocene geochronology, 02 Langhian, * Serravallian, * {{geochronology-stub ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Retroposon
Retroposons are repetitive DNA fragments which are inserted into chromosomes after they had been reverse transcribed from any RNA molecule. Difference between retroposons and retrotransposons In contrast to retrotransposons, retroposons never encode reverse transcriptase (RT) (but see below). Therefore, they are non-autonomous elements with regard to transposition activity (as opposed to transposons). Non-long terminal repeat (LTR) retrotransposons such as the human LINE1 elements are sometimes falsely referred to as retroposons. However, this depends on the author. For example, Howard Temin published the following definition: Retroposons encode RT but are devoid of long terminal repeats (LTRs), for example long interspersed elements (LINEs). Retrotransposons also feature LTRs and retroviruses, in addition, are packaged as viral particles (virions). Retrosequences are non-autonomous elements devoid of RT. They are retroposed with the aid of the machinery of autonomous elemen ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Mustelidae
The Mustelidae (; from Latin , weasel) are a diverse family of carnivora, carnivoran mammals, including weasels, badgers, otters, polecats, martens, grisons, and wolverines. Otherwise known as mustelids (), they form the largest family in the suborder Caniformia of the order (biology), order Carnivora with about 66 to 70 species in nine subfamilies. Variety Mustelids vary greatly in size and behaviour. The smaller variants of the least weasel can be under in length, while the giant otter of Amazon rainforest, Amazonian South America can measure up to and sea otters can exceed in weight. Wolverines can crush bones as thick as the femur of a moose to get at the Bone marrow, marrow, and have been seen attempting to drive bears away from their kills. The sea otter uses rocks to break open shellfish to eat. Martens are largely arboreal, while European badgers dig extensive tunnel networks, called setts. Only one mustelid has been domesticated; the ferret. Tayra are also kept ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Genetics
Genetics is the study of genes, genetic variation, and heredity in organisms.Hartl D, Jones E (2005) It is an important branch in biology because heredity is vital to organisms' evolution. Gregor Mendel, a Moravian Augustinians, Augustinian friar working in the 19th century in Brno, was the first to study genetics scientifically. Mendel studied "trait inheritance", patterns in the way traits are handed down from parents to offspring over time. He observed that organisms (pea plants) inherit traits by way of discrete "units of inheritance". This term, still used today, is a somewhat ambiguous definition of what is referred to as a gene. Phenotypic trait, Trait inheritance and Molecular genetics, molecular inheritance mechanisms of genes are still primary principles of genetics in the 21st century, but modern genetics has expanded to study the function and behavior of genes. Gene structure and function, variation, and distribution are studied within the context of the Cell (bi ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Red Pandas
The red panda (''Ailurus fulgens''), also known as the lesser panda, is a small mammal native to the eastern Himalayas and southwestern China. It has dense reddish-brown fur with a black belly and legs, white-lined ears, a mostly white muzzle and a ringed tail. Its head-to-body length is with a tail, and it weighs between . It is well adapted to climbing due to its flexible joints and curved semi-retractile claws. The red panda was formally described in 1825. The two currently recognised subspecies, the Himalayan and the Chinese red panda, genetically diverged about 250,000 years ago. The red panda's place on the evolutionary tree has been debated, but modern genetic evidence places it in close affinity with raccoons, weasels, and skunks. It is not closely related to the giant panda, which is a bear, though both possess elongated wrist bones or " false thumbs" used for grasping bamboo. The evolutionary lineage of the red panda ( Ailuridae) stretches back around , as ind ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Ailuridae
Ailuridae is a family in the mammal order Carnivora. The family consists of the red panda (the sole living representative) and its extinct relatives. Georges Cuvier first described ''Ailurus'' as belonging to the raccoon family in 1825; this classification has been controversial ever since. It was classified in the raccoon family because of morphological similarities of the head, colored ringed tail, and other morphological and ecological characteristics. Somewhat later, it was assigned to the bear family. Molecular phylogenetic studies had shown that, as an ancient species in the order Carnivora, the red panda is relatively close to the American raccoon and may be either a monotypic family or a subfamily within the procyonid family. An in-depth mitochondrial DNA population analysis study stated: "According to the fossil record, the Red Panda diverged from its common ancestor with bears about 40 million years ago." With this divergence, by comparing the sequence difference ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Procyonidae
Procyonidae ( ) is a New World family of the order Carnivora. It includes the raccoons, ringtails, cacomistles, coatis, kinkajous, olingos, and olinguitos. Procyonids inhabit a wide range of environments and are generally omnivorous. Characteristics Procyonids are relatively small animals, with generally slender bodies and long tails, though the common raccoon tends to be bulky. Because of their general build, the Procyonidae are often popularly viewed as smaller cousins of the bear family. This is apparent in their German name, ''Kleinbären'' (small bears), including the names of the species: a raccoon is called a ''Waschbär'' (washing bear, as it "washes" its food before eating), a coati is a ''Nasenbär'' (nose-bear), while a kinkajou is a ''Honigbär'' (honey-bear). Dutch follows suit, calling the animals ''wasbeer'', ''neusbeer'' and ''rolstaartbeer'' (curl-tail bear) respectively. However, it is now believed that procyonids are more closely related to musteli ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
