1.
Black mamba
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The black mamba is a venomous snake endemic to parts of sub-Saharan Africa. Skin colour varies from grey to dark brown, juvenile black mambas tend to be lighter in color than adults and darken with age. It is the longest species of venomous snake indigenous to the African continent, mature specimens generally exceed 2 meters, specimens of 4.3 to 4.5 meters have been reported. Although most mamba species are tree-dwelling snakes, the black mamba is not generally arboreal and these include savannah, woodlands, rocky slopes and in some regions dense forest. It is diurnal and chiefly an ambush predator, known to prey on hyrax, bushbabies and it is also a pursuit predator, in this it resembles some other long, speedy, highly-venomous species with well-developed vision. Over suitable surfaces it is possibly the speediest species of snake, adult mambas have few natural predators. In a threat display, the mamba usually opens its inky black mouth, spreads its narrow neck-flap and it is capable of striking at considerable range and occasionally may deliver a series of bites in rapid succession. Its venom is composed of potent neurotoxins that may cause fast onset of symptoms. Despite its reputation for being formidable and highly aggressive, like most snakes, not being proximal to humans, bites from the black mamba are not frequent. The black mamba, Dendroaspis polylepis, is an elapid within the genus Dendroaspis, although it had been known to missionaries and residents, prior to 1860, by the name mamba, which was already established in the vernacular and taken from the Zulu word imamba. The first formal description was made by Albert Günther in 1864, in 1873, Wilhelm Peters described two subspecies, the nominotypical D. polylepis polylepis and also D. polylepis antinorii. However, these are no longer held to be distinct, in 1896, Boulenger combined the species as a whole with the eastern green mamba, a lumping diagnosis that remained in force until 1946, when FitzSimons split them again into separate species. The generic name, Dendroaspis, derives from Ancient Greek dendro, meaning tree, and aspis, which is understood to mean shield, via Latin aspis, it is the source of the English word asp. In ancient texts, aspis or asp often referred to the Egyptian cobra, thus, Dendroaspis literally means tree asp, reflecting the arboreal nature of most of the species within the genus. The genus was first described by the German ornithologist and herpetologist Hermann Schlegel in 1848, slowinski et al. pointed out that the relationships of the African genus Dendroaspis are problematical. However, evidence suggests that Dendroaspis, Ophiophagus, Bungarus, the specific epithet polylepis is derived from the Ancient Greek poly meaning many and lepis meaning scale. It apparently refers to the count of this species, which is higher than some other species in the genus. Dendroaspis polylepis is a large, round-bodied, slender, but powerful snake and it tapers smoothly towards the tail, and is of markedly more robust build than its distinctly gracile congeners Dendroaspis angusticeps and Dendroaspis viridis
2.
Taxonomy (biology)
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Taxonomy is the science of defining groups of biological organisms on the basis of shared characteristics and giving names to those groups. The exact definition of taxonomy varies from source to source, but the core of the remains, the conception, naming. There is some disagreement as to whether biological nomenclature is considered a part of taxonomy, the broadest meaning of taxonomy is used here. The word taxonomy was introduced in 1813 by Candolle, in his Théorie élémentaire de la botanique, the term alpha taxonomy is primarily used today to refer to the discipline of finding, describing, and naming taxa, particularly species. In earlier literature, the term had a different meaning, referring to morphological taxonomy, ideals can, it may be said, never be completely realized. They have, however, a value of acting as permanent stimulants. Some of us please ourselves by thinking we are now groping in a beta taxonomy, turrill thus explicitly excludes from alpha taxonomy various areas of study that he includes within taxonomy as a whole, such as ecology, physiology, genetics, and cytology. He further excludes phylogenetic reconstruction from alpha taxonomy, thus, Ernst Mayr in 1968 defined beta taxonomy as the classification of ranks higher than species. This activity is what the term denotes, it is also referred to as beta taxonomy. How species should be defined in a group of organisms gives rise to practical and theoretical problems that are referred to as the species problem. The scientific work of deciding how to define species has been called microtaxonomy, by extension, macrotaxonomy is the study of groups at higher taxonomic ranks, from subgenus and above only, than species. While some descriptions of taxonomic history attempt to date taxonomy to ancient civilizations, earlier works were primarily descriptive, and focused on plants that were useful in agriculture or medicine. There are a number of stages in scientific thinking. Early taxonomy was based on criteria, the so-called artificial systems. Later came systems based on a complete consideration of the characteristics of taxa, referred to as natural systems, such as those of de Jussieu, de Candolle and Bentham. The publication of Charles Darwins Origin of Species led to new ways of thinking about classification based on evolutionary relationships and this was the concept of phyletic systems, from 1883 onwards. This approach was typified by those of Eichler and Engler, the advent of molecular genetics and statistical methodology allowed the creation of the modern era of phylogenetic systems based on cladistics, rather than morphology alone. Taxonomy has been called the worlds oldest profession, and naming and classifying our surroundings has likely been taking place as long as mankind has been able to communicate
3.
Animal
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Animals are multicellular, eukaryotic organisms of the kingdom Animalia. The animal kingdom emerged as a clade within Apoikozoa as the group to the choanoflagellates. Animals are motile, meaning they can move spontaneously and independently at some point in their lives and their body plan eventually becomes fixed as they develop, although some undergo a process of metamorphosis later in their lives. All animals are heterotrophs, they must ingest other organisms or their products for sustenance, most known animal phyla appeared in the fossil record as marine species during the Cambrian explosion, about 542 million years ago. Animals can be divided broadly into vertebrates and invertebrates, vertebrates have a backbone or spine, and amount to less than five percent of all described animal species. They include fish, amphibians, reptiles, birds and mammals, the remaining animals are the invertebrates, which lack a backbone. These include molluscs, arthropods, annelids, nematodes, flatworms, cnidarians, ctenophores, the study of animals is called zoology. The word animal comes from the Latin animalis, meaning having breath, the biological definition of the word refers to all members of the kingdom Animalia, encompassing creatures as diverse as sponges, jellyfish, insects, and humans. Aristotle divided the world between animals and plants, and this was followed by Carl Linnaeus, in the first hierarchical classification. In Linnaeuss original scheme, the animals were one of three kingdoms, divided into the classes of Vermes, Insecta, Pisces, Amphibia, Aves, and Mammalia. Since then the last four have all been subsumed into a single phylum, in 1874, Ernst Haeckel divided the animal kingdom into two subkingdoms, Metazoa and Protozoa. The protozoa were later moved to the kingdom Protista, leaving only the metazoa, thus Metazoa is now considered a synonym of Animalia. Animals have several characteristics that set apart from other living things. Animals are eukaryotic and multicellular, which separates them from bacteria and they are heterotrophic, generally digesting food in an internal chamber, which separates them from plants and algae. They are also distinguished from plants, algae, and fungi by lacking cell walls. All animals are motile, if only at life stages. In most animals, embryos pass through a stage, which is a characteristic exclusive to animals. With a few exceptions, most notably the sponges and Placozoa and these include muscles, which are able to contract and control locomotion, and nerve tissues, which send and process signals
4.
Chordate
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Chordates are deuterostomes, as during the embryo development stage the anus forms before the mouth. They are also bilaterally symmetric coelomates, in the case of vertebrate chordates, the notochord is usually replaced by a vertebral column during development, and they may have body plans organized via segmentation. There are also additional extinct taxa, the Vertebrata are sometimes considered as a subgroup of the clade Craniata, consisting of chordates with a skull, the Craniata and Tunicata compose the clade Olfactores. Of the more than 65,000 living species of chordates, the worlds largest and fastest animals, the blue whale and peregrine falcon respectively, are chordates, as are humans. Fossil chordates are known from at least as early as the Cambrian explosion, Hemichordata, which includes the acorn worms, has been presented as a fourth chordate subphylum, but it now is usually treated as a separate phylum. The Hemichordata, along with the Echinodermata, form the Ambulacraria, the Chordata and Ambulacraria form the superphylum Deuterostomia, composed of the deuterostomes. Attempts to work out the relationships of the chordates have produced several hypotheses. All of the earliest chordate fossils have found in the Early Cambrian Chengjiang fauna. Because the fossil record of early chordates is poor, only molecular phylogenetics offers a prospect of dating their emergence. However, the use of molecular phylogenetics for dating evolutionary transitions is controversial and it has also proved difficult to produce a detailed classification within the living chordates. Attempts to produce family trees shows that many of the traditional classes are paraphyletic. While this has been known since the 19th century, an insistence on only monophyletic taxa has resulted in vertebrate classification being in a state of flux. Although the name Chordata is attributed to William Bateson, it was already in prevalent use by 1880, ernst Haeckel described a taxon comprising tunicates, cephalochordates, and vertebrates in 1866. Though he used the German vernacular form, it is allowed under the ICZN code because of its subsequent latinization, among the vertebrate sub-group of chordates the notochord develops into the spine, and in wholly aquatic species this helps the animal to swim by flexing its tail. In fish and other vertebrates, this develops into the spinal cord, the pharynx is the part of the throat immediately behind the mouth. In fish, the slits are modified to form gills, a muscular tail that extends backwards behind the anus. This is a groove in the wall of the pharynx. In filter-feeding species it produces mucus to gather food particles, which helps in transporting food to the esophagus and it also stores iodine, and may be a precursor of the vertebrate thyroid gland
5.
Reptile
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Reptiles are tetrapod animals in the class Reptilia, comprising todays turtles, crocodilians, snakes, amphisbaenians, lizards, tuatara, and their extinct relatives. The study of these traditional reptile orders, historically combined with that of amphibians, is called herpetology. Because some reptiles are more related to birds than they are to other reptiles. For this reason, many scientists prefer to consider the birds part of Reptilia as well. Some early examples include the lizard-like Hylonomus and Casineria, in addition to the living reptiles, there are many diverse groups that are now extinct, in some cases due to mass extinction events. In particular, the K–Pg extinction wiped out the pterosaurs, plesiosaurs, ornithischians, and sauropods, as well as species of theropods, crocodyliforms. Modern non-avian reptiles inhabit every continent with the exception of Antarctica, several living subgroups are recognized, Testudines, approximately 400 species, Sphenodontia,1 species, Squamata, over 9,600 species, Crocodilia,25 species, and Aves,10,000 species. Reptiles are tetrapod vertebrates, creatures that either have four limbs or, unlike amphibians, reptiles do not have an aquatic larval stage. As amniotes, reptile eggs are surrounded by membranes for protection and transport, many of the viviparous species feed their fetuses through various forms of placenta analogous to those of mammals, with some providing initial care for their hatchlings. In the 18th century, the reptiles were, from the outset of classification, the terms reptile and amphibian were largely interchangeable, reptile being preferred by the French. Josephus Nicolaus Laurenti was the first to use the term Reptilia for an expanded selection of reptiles. Today, the two groups are commonly treated under the same heading as herptiles. He subsequently proposed the names of Sauropsida and Ichthyopsida for the two groups. In 1866, Haeckel demonstrated that vertebrates could be divided based on their strategies, and that reptiles, birds. The terms Sauropsida and Theropsida were used again in 1916 by E. S, Goodrich to distinguish between lizards, birds, and their relatives on the one hand and mammals and their extinct relatives on the other. Goodrich supported this division by the nature of the hearts and blood vessels in each group, according to Goodrich, both lineages evolved from an earlier stem group, Protosauria in which he included some animals today considered reptile-like amphibians, as well as early reptiles. Watson observed that the first two groups diverged very early in history, so he divided Goodrichs Protosauria between them. He also reinterpreted Sauropsida and Theropsida to exclude birds and mammals, thus his Sauropsida included Procolophonia, Eosuchia, Millerosauria, Chelonia, Squamata, Rhynchocephalia, Crocodilia, thecodonts, non-avian dinosaurs, pterosaurs, ichthyosaurs, and sauropterygians
6.
Squamata
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The Squamata, or the scaled reptiles, are the largest recent order of reptiles, comprising all lizards and snakes. With over 10,000 species, it is also the second-largest order of extant vertebrates, after the perciform fish, members of the order are distinguished by their skins, which bear horny scales or shields. They also possess movable quadrate bones, making it possible to move the upper jaw relative to the neurocranium and this is particularly visible in snakes, which are able to open their mouths very wide to accommodate comparatively large prey. They are the most variably sized order of reptiles, ranging from the 16 mm dwarf gecko to the 5.21 m green anaconda and the now-extinct mosasaurs, among the other reptiles, squamates are most closely related to the tuatara, which strongly resembles lizards. Squamates are a sister group to the tuatara. The squamates and tuatara together are a group to crocodiles and birds. Fossils of the sister group, the Rhynchocephalia, appear in the Early Triassic. Also appearing in the Cretaceous are the polyglyphanodonts, a group of uncertain affinities, and the mosasaurs. At the end of the Cretaceous, squamates suffered a major extinction at the K-T boundary which wiped out polyglyphanodonts, mosasaurs, the relationships of squamates have been debated. From morphological data, the iguanians were long thought to be the most ancient branch of the tree, however, iguanians are now united with snakes and anguimorphs in a group called the Toxicofera. DNA also suggests that the various limbless groups- snakes, amphisbaenians, and dibamids- are unrelated, the male members of the group Squamata have hemipenes, which are usually held inverted within their bodies, and are everted for reproduction via erectile tissue like that in the human penis. Only one is used at a time, and some evidence indicates that males alternate use between copulations, the hemipenis has a variety of shapes, depending on the species. Often it bears spines or hooks, to anchor the male within the female, some species even have forked hemipenes. Due to being everted and inverted, hemipenes do not have a completely enclosed channel for the conduction of sperm and this is also the only reptile group in which both viviparous and ovoviviparous species are found, as well as the usual oviparous reptiles. Some species, such as the Komodo dragon, can reproduce asexually through parthenogenesis. There have been studies on how sexual selection manifests itself in snakes, snakes use a variety of tactics in acquiring mates. It is common for neck biting to occur while the snakes are entwined, parthenogenesis is a natural form of reproduction in which growth and development of embryos occur without fertilization. Agkistrodon contortrix and Agkistrodon piscivorus can reproduce by facultative parthenogenesis and that is, they are capable of switching from a sexual mode of reproduction to an asexual mode
7.
Snake
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Snakes are elongated, legless, carnivorous reptiles of the suborder Serpentes that can be distinguished from legless lizards by their lack of eyelids and external ears. Like all squamates, snakes are ectothermic, amniote vertebrates covered in overlapping scales, many species of snakes have skulls with several more joints than their lizard ancestors, enabling them to swallow prey much larger than their heads with their highly mobile jaws. To accommodate their bodies, snakes paired organs appear one in front of the other instead of side by side. Some species retain a pelvic girdle with a pair of claws on either side of the cloaca. Additionally, sea snakes are widespread throughout the Indian and Pacific Oceans, more than 20 families are currently recognized, comprising about 500 genera and about 3,400 species. They range in size from the tiny,10.4 cm -long thread snake to the reticulated python of 6.95 meters in length, the fossil species Titanoboa cerrejonensis was 12.8 meters long. Snakes are thought to have evolved from either burrowing or aquatic lizards, perhaps during the Jurassic period, the diversity of modern snakes appeared during the Paleocene period. The oldest preserved descriptions of snakes can be found in the Brooklyn Papyrus, most species are nonvenomous and those that have venom use it primarily to kill and subdue prey rather than for self-defense. Some possess venom potent enough to cause injury or death to humans. Nonvenomous snakes either swallow prey alive or kill by constriction, the word ousted adder, as adder went on to narrow in meaning, though in Old English næddre was the general word for snake. The other term, serpent, is from French, ultimately from Indo-European *serp-, the fossil record of snakes is relatively poor because snake skeletons are typically small and fragile making fossilization uncommon. Fossils readily identifiable as snakes first appear in the record during the Cretaceous period. The earliest known snake fossils come from the marine simoliophiids. Based on comparative anatomy, there is consensus that snakes descended from lizards, pythons and boas—primitive groups among modern snakes—have vestigial hind limbs, tiny, clawed digits known as anal spurs, which are used to grasp during mating. The families Leptotyphlopidae and Typhlopidae also possess remnants of the pelvic girdle, front limbs are nonexistent in all known snakes. This is caused by the evolution of Hox genes, controlling limb morphogenesis, the axial skeleton of the snakes’ common ancestor, like most other tetrapods, had regional specializations consisting of cervical, thoracic, lumbar, sacral, and caudal vertebrae. Early in snake evolution, the Hox gene expression in the axial skeleton responsible for the development of the thorax became dominant, as a result, the vertebrae anterior to the hindlimb buds all have the same thoracic-like identity. In other words, most of a skeleton is an extremely extended thorax
8.
Elapidae
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Elapid snakes exhibit a wide range of sizes, from 18-cm species of Drysdalia to the 5. 6-m king cobra. All elapids are characterized by hollow, fixed fangs through which they inject venom, currently,325 species in 61 genera are recognized,58 genera and 251 species are in the Old World, against a minor diversity of three genera and 74 species in the New World. All elapids have a pair of proteroglyphous fangs used to inject venom from glands located towards the rear of the upper jaws, in addition, their behavior is usually quite active, and most are oviparous. Some elapids are strongly arboreal, while others are more or less specialised burrowers in either humid or arid environments. Sea snakes have adapted to a way of life in different ways. All have evolved paddle-like tails for swimming and the ability to excrete salt, most also have laterally compressed bodies, their ventral scales are much reduced in size, their nostrils are located dorsally, and they give birth to live young. The sea kraits are the sea snakes least adapted to aquatic life and they spend much of their time on land, where they lay their eggs. They have wide ventral scales, their tails are not as well-developed for swimming, the fangs, which are enlarged and hollow, are the first two teeth on each maxillary bone. Usually only one fang is in place on each side at any time, the maxilla is intermediate in both length and mobility between typical colubrids and viperids. A few species are capable of spraying their venom from forward-facing holes at the tips of their fangs using pressure, on land, these snakes are found worldwide in tropical and subtropical regions, except in Europe. Sea snakes occur mainly in the Indian Ocean and the southwest Pacific, however, the range of one species, Pelamis platura, extends across the Pacific to the coasts of Central and South America. Many elapids are potentially deadly venomous snakes and their venom is mainly neurotoxic, although many of them also possess several other types of toxins, including cardiotoxins and cytotoxins. This family has some members considered to be the worlds most venomous land snakes based on the murine LD50 of their venom, such as the inland taipan. Additionally, some large-sized elapids, such as the Asiatic king cobra, African black mamba, forest cobra, elapids use their venom both to immobilize their prey and in self-defense. * Not including the nominate subspecies The table above lists all of the elapid genera, in the past, many subfamilies were recognized, or have been suggested for the Elapidae, including the Elapinae, Hydrophiinae, Micrurinae, Acanthophiinae and the Laticaudinae. It is believed that the Laticauda and the sea snakes evolved separately from Australasian land snakes. Asian cobras, coral snakes, and American coral snakes also appear to be monophyletic, the type genus for the Elapidae was originally Elaps, but the group was moved to another family. In contrast to what is typical of botany, the Elapidae family was not renamed, in the meantime, Elaps was renamed Homoroselaps and moved back to the Elapidae
9.
Hermann Schlegel
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Hermann Schlegel was a German ornithologist and herpetologist. Schlegel was born at Altenburg, the son of a brassfounder and his father collected butterflies, which stimulated Schlegels interest in natural history. The discovery, by chance, of a buzzards nest led him to the study of birds, Schlegel started to work for his father, but soon tired of it. He travelled to Vienna in 1824, where, at the university, he attended the lectures of Leopold Fitzinger, a letter of introduction from Brehm to Joseph Natterer gained him a position at the Naturhistorisches Museum. At first Schlegel worked mainly on the collection and wrote Essai sur la Physionomie des Serpens. It was at time that Schlegel met Philipp Franz von Siebold. They became firm friends and collaborated on Fauna Japonica, in 1847 he became correspondent of the Royal Institute of the Netherlands, when that became the Royal Netherlands Academy of Arts and Sciences in 1851 he became member. When Temminck died at the beginning of 1858, Schlegel succeeded him as director of the history museum. Schlegel was particularly interested in Southeast Asia, and in 1857 sent his son Gustav to collect birds in China, Gustav arrived to find that Robert Swinhoe had gotten there first. In 1859, Schlegel sent Heinrich Agathon Bernstein to collect birds in New Guinea, after the death of Bernstein in 1865, he was succeeded by Hermann von Rosenberg. Schlegel took on an assistant, Otto Finsch. At the same time, he started to publish a magazine, Notes from the Leyden Museum, as well as a vast work of 14 volumes. He employed three talented illustrators, John Gerrard Keulemans, Joseph Smit and Joseph Wolf. The end of Schlegels life was difficult, his wife died in 1864, Finsch moved to the history museum at Bremen. Schlegel died on 17 January 1884 in Leiden, bromley, Kent, Christopher Helm Publishers Ltd.256 pp. ISBN 1-873403-97-6
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