1.
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
2.
Plant
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Plants are mainly multicellular, predominantly photosynthetic eukaryotes of the kingdom Plantae. The term is generally limited to the green plants, which form an unranked clade Viridiplantae. This includes the plants, conifers and other gymnosperms, ferns, clubmosses, hornworts, liverworts, mosses and the green algae. Green plants have cell walls containing cellulose and obtain most of their energy from sunlight via photosynthesis by primary chloroplasts and their chloroplasts contain chlorophylls a and b, which gives them their green color. Some plants are parasitic and have lost the ability to produce amounts of chlorophyll or to photosynthesize. Plants are characterized by sexual reproduction and alternation of generations, although reproduction is also common. There are about 300–315 thousand species of plants, of which the great majority, green plants provide most of the worlds molecular oxygen and are the basis of most of Earths ecologies, especially on land. Plants that produce grains, fruits and vegetables form humankinds basic foodstuffs, Plants play many roles in culture. They are used as ornaments and, until recently and in variety, they have served as the source of most medicines. The scientific study of plants is known as botany, a branch of biology, Plants are one of the two groups into which all living things were traditionally divided, the other is animals. The division goes back at least as far as Aristotle, who distinguished between plants, which generally do not move, and animals, which often are mobile to catch their food. Much later, when Linnaeus created the basis of the system of scientific classification. Since then, it has become clear that the plant kingdom as originally defined included several unrelated groups, however, these organisms are still often considered plants, particularly in popular contexts. When the name Plantae or plant is applied to a group of organisms or taxon. The evolutionary history of plants is not yet settled. Those which have been called plants are in bold, the way in which the groups of green algae are combined and named varies considerably between authors. Algae comprise several different groups of organisms which produce energy through photosynthesis, most conspicuous among the algae are the seaweeds, multicellular algae that may roughly resemble land plants, but are classified among the brown, red and green algae. Each of these groups also includes various microscopic and single-celled organisms
3.
Flowering plant
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The flowering plants, also known as Angiospermae or Magnoliophyta, are the most diverse group of land plants, with 416 families, approx. 13,164 known genera and a total of c.295,383 known species, etymologically, angiosperm means a plant that produces seeds within an enclosure, in other words, a fruiting plant. The term angiosperm comes from the Greek composite word meaning enclosed seeds, the ancestors of flowering plants diverged from gymnosperms in the Triassic Period, during the range 245 to 202 million years ago, and the first flowering plants are known from 160 mya. They diversified extensively during the Lower Cretaceous, became widespread by 120 mya, angiosperms differ from other seed plants in several ways, described in the table. These distinguishing characteristics taken together have made the angiosperms the most diverse and numerous land plants, the amount and complexity of tissue-formation in flowering plants exceeds that of gymnosperms. The vascular bundles of the stem are arranged such that the xylem and phloem form concentric rings, in the dicotyledons, the bundles in the very young stem are arranged in an open ring, separating a central pith from an outer cortex. In each bundle, separating the xylem and phloem, is a layer of meristem or active formative tissue known as cambium, the soft phloem becomes crushed, but the hard wood persists and forms the bulk of the stem and branches of the woody perennial. Among the monocotyledons, the bundles are more numerous in the stem and are scattered through the ground tissue. They contain no cambium and once formed the stem increases in diameter only in exceptional cases, the characteristic feature of angiosperms is the flower. Flowers show remarkable variation in form and elaboration, and provide the most trustworthy external characteristics for establishing relationships among angiosperm species, the function of the flower is to ensure fertilization of the ovule and development of fruit containing seeds. The floral apparatus may arise terminally on a shoot or from the axil of a leaf, occasionally, as in violets, a flower arises singly in the axil of an ordinary foliage-leaf. There are two kinds of cells produced by flowers. Microspores, which divide to become pollen grains, are the male cells and are borne in the stamens. The female cells called megaspores, which divide to become the egg cell, are contained in the ovule. The flower may consist only of parts, as in willow. Usually, other structures are present and serve to protect the sporophylls, the individual members of these surrounding structures are known as sepals and petals. The outer series is usually green and leaf-like, and functions to protect the rest of the flower, the inner series is, in general, white or brightly colored, and is more delicate in structure. It functions to attract insect or bird pollinators, attraction is effected by color, scent, and nectar, which may be secreted in some part of the flower
4.
Malus
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Malus is a genus of about 30–55 species of small deciduous apple trees or shrubs in the family Rosaceae, including the domesticated orchard apple. The other species are known as crabapples, crab apples, crabs. The genus is native to the zone of the Northern Hemisphere. Apple trees are typically 4–12 m tall at maturity, with a dense, the leaves are 3–10 cm long, alternate, simple, with a serrated margin. Apples require cross-pollination between individuals by insects, all are self-sterile, and self-pollination is impossible, making pollinating insects essential, several Malus species, including domestic apples, hybridize freely. They are used as food plants by the larvae of a number of Lepidoptera species. The centre of the fruit contains five carpels arranged star-like, each containing one or two seeds, for the Malus pumila cultivars, the cultivated apples, see Apple. Crabapples are popular as ornamental trees, providing blossom in Spring. The fruits often persist throughout Winter, numerous hybrid cultivars have been selected, of which Evereste and Red Sentinel have gained The Royal Horticultural Societys Award of Garden Merit. Other varieties are dealt with under their species names, some crabapples are used as rootstocks for domestic apples to add beneficial characteristics. For example, varieties of Baccata, also called Siberian crab and they are also used as pollinizers in apple orchards. In emergencies, a bucket or drum bouquet of crabapple flowering branches are placed near the beehives as orchard pollenizers. Crabapple fruit is not an important crop in most areas, being extremely sour due to acid, and in some species woody. In some southeast Asian cultures they are valued as a condiment, sometimes eaten with salt and chili pepper. Some crabapple varieties are an exception to the reputation of being sour, crabapples are an excellent source of pectin, and their juice can be made into a ruby-coloured preserve with a full, spicy flavour. A small percentage of crabapples in cider makes a more interesting flavour, as Old English Wergulu, the crab apple is one of the nine plants invoked in the pagan Anglo-Saxon Nine Herbs Charm, recorded in the 10th century. Apple wood gives off a pleasant scent when burned, and smoke from a wood fire gives an excellent flavour to smoked foods. It is easier to cut when green, dry wood is exceedingly difficult to carve by hand
5.
Carl Linnaeus
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Carl Linnaeus, also known after his ennoblement as Carl von Linné, was a Swedish botanist, physician, and zoologist, who formalised the modern system of naming organisms called binomial nomenclature. He is known by the father of modern taxonomy. Many of his writings were in Latin, and his name is rendered in Latin as Carolus Linnæus, Linnaeus was born in the countryside of Småland, in southern Sweden. He received most of his education at Uppsala University. He lived abroad between 1735 and 1738, where he studied and also published a first edition of his Systema Naturae in the Netherlands and he then returned to Sweden, where he became professor of medicine and botany at Uppsala. In the 1740s, he was sent on journeys through Sweden to find and classify plants. In the 1750s and 1760s, he continued to collect and classify animals, plants, and minerals, at the time of his death, he was one of the most acclaimed scientists in Europe. The philosopher Jean-Jacques Rousseau sent him the message, Tell him I know no man on earth. The German writer Johann Wolfgang von Goethe wrote, With the exception of Shakespeare and Spinoza, Swedish author August Strindberg wrote, Linnaeus was in reality a poet who happened to become a naturalist. Among other compliments, Linnaeus has been called Princeps botanicorum, The Pliny of the North and he is also considered as one of the founders of modern ecology. In botany, the abbreviation used to indicate Linnaeus as the authority for species names is L. In older publications, sometimes the abbreviation Linn. is found, Linnæus was born in the village of Råshult in Småland, Sweden, on 23 May 1707. He was the first child of Nicolaus Ingemarsson and Christina Brodersonia and his siblings were Anna Maria Linnæa, Sofia Juliana Linnæa, Samuel Linnæus, and Emerentia Linnæa. One of a line of peasants and priests, Nils was an amateur botanist, a Lutheran minister. Christina was the daughter of the rector of Stenbrohult, Samuel Brodersonius, a year after Linnæus birth, his grandfather Samuel Brodersonius died, and his father Nils became the rector of Stenbrohult. The family moved into the rectory from the curates house, even in his early years, Linnæus seemed to have a liking for plants, flowers in particular. Whenever he was upset, he was given a flower, which calmed him. Nils spent much time in his garden and often showed flowers to Linnaeus, soon Linnæus was given his own patch of earth where he could grow plants
6.
Thorns, spines, and prickles
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Leaf margins may also have teeth, and if those teeth are sharp, they are called spinose teeth on a spinose leaf margin. On a leaf apex, if there is a process, and if it is especially sharp, stiff. When the leaf epidermis is covered very long, stiff trichomes, it may be referred to as a hispid vestiture, if the trichomes are stinging trichomes. There can be found also spines or spinose structures derived from roots, the predominant function of thorns, spines and prickles is deterring herbivory in a mechanical form. For this reason they are classified as physical or mechanical defenses, not all functions of spines or glochids are limited to defense from physical attacks by herbivores and other animals. In some cases, spines have been shown to shade or insulate the plants that grow them, for example, saguaro cactus spines shade the apical meristem in summer, and in members of the Opuntioideae, glochids insulate the apical meristem in winter. Agrawal et al. found that seem to have little effect on specialist pollinators. Thorns are modified branches or stems and they may be simple or branched. Spines are modified leaves, stipules, or parts of leaves, some authors prefer not to distinguish spines from thorns because, like thorns, and unlike prickles, they commonly contain vascular tissue. The plants of the family are particularly well known for their dense covering of spines. Cacti often have a kind of spine called a glochidium or glochid. Prickles are comparable to hairs but can be quite coarse and they are extensions of the cortex and epidermis. Technically speaking, many plants commonly thought of as having thorns or spines actually have prickles, other similar structures are spinose teeth, spinose apical processes, and trichomes. Trichomes are often effective defenses against small insect herbivores, thorns, spines, spinescent is a term describing plants that bear any sharp structures that deter herbivory. It also can refer to the state of tending to be or become spiny in some sense or degree, there are also spines derived from roots, like the ones on the trunk of the Root Spine Palms. The trunk roots of Cryosophila guagara grow downwards to a length of 6–12 cm, then stop growing, the anatomy of crown roots on this species also alters during their life. They initially grow upwards and then turn down and finally they, too, lateral roots on these two types of roots, as well as those on the stilt roots on this species, also become spinous. Some authors believe that some of these short spiny laterals have a ventilating function so they are pneumorhizae, short spiny laterals that may have a ventilating funcion may also be found on roots of Iriartea exorrhiza
7.
Apple
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The apple tree is a deciduous tree in the rose family best known for its sweet, pomaceous fruit, the apple. It is cultivated worldwide as a tree, and is the most widely grown species in the genus Malus. The tree originated in Central Asia, where its wild ancestor, Apples have been grown for thousands of years in Asia and Europe, and were brought to North America by European colonists. Apples have religious and mythological significance in many cultures, including Norse, Greek, Apple trees are large if grown from seed. Generally apple cultivars are propagated by grafting onto rootstocks, which control the size of the resulting tree, There are more than 7,500 known cultivars of apples, resulting in a range of desired characteristics. Different cultivars are bred for various tastes and uses, including cooking, eating raw, trees and fruit are prone to a number of fungal, bacterial and pest problems, which can be controlled by a number of organic and non-organic means. In 2010, the genome was sequenced as part of research on disease control. Worldwide production of apples in 2014 was 84.6 million tonnes, the apple is a deciduous tree, generally standing 1.8 to 4.6 m tall in cultivation and up to 12 m in the wild. When cultivated, the size, shape and branch density are determined by rootstock selection, the leaves are alternately arranged dark green-colored simple ovals with serrated margins and slightly downy undersides. Blossoms are produced in spring simultaneously with the budding of the leaves, the 3 to 4 cm flowers are white with a pink tinge that gradually fades, five petaled, with an inflorescence consisting of a cyme with 4–6 flowers. The central flower of the inflorescence is called the king bloom, it opens first, the fruit matures in late summer or autumn, and cultivars exist with a wide range of sizes. Commercial growers aim to produce an apple that is 7.0 to 8.3 cm in diameter, due to market preference. Some consumers, especially those in Japan, prefer a larger apple, while apples below 5.7 cm are generally used for making juice and have little market value. The skin of ripe apples is generally red, yellow, green, pink, the skin may also be wholly or partly russeted i. e. rough and brown. The skin is covered in a layer of epicuticular wax. The exocarp is generally pale yellowish-white, though pink or yellow also occur. The original wild ancestor of Malus pumila was Malus sieversii, found growing wild in the mountains of Central Asia in southern Kazakhstan, Kyrgyzstan, Tajikistan, in strains without recent admixture the contribution of the latter predominates. It had about 57,000 genes, the highest number of any plant genome studied to date and this new understanding of the apple genome will help scientists in identifying genes and gene variants that contribute to resistance to disease and drought, and other desirable characteristics
8.
Plant reproductive morphology
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Plant reproductive morphology is the study of the physical form and structure of those parts of plants directly or indirectly concerned with sexual reproduction. Among all living organisms, flowers, which are the structures of angiosperms, are the most varied physically. Plants that are not flowering plants also have complex interplays between morphological adaptation and environmental factors in their sexual reproduction, christian Konrad Sprengel studied the reproduction of flowering plants and for the first time it was understood that the pollination process involved both biotic and abiotic interactions. Charles Darwins theories of natural selection utilized this work to build his theory of evolution, Plants have complex lifecycles involving alternation of generations. One generation, the sporophyte, gives rise to the next generation asexually via spores, spores may be identical isospores or come in different sizes, but strictly speaking, spores and sporophytes are neither male nor female because they do not produce gametes. The alternate generation, the gametophyte, produces gametes, eggs and/or sperm, a gametophyte can be be monoicous, producing both eggs and sperm or dioicous, either female or male. In the bryophytes, the gametophyte is the dominant generation. In ferns and seed plants the sporophyte is the dominant generation, the obvious visible plant, whether a small herb or a large tree, is the sporophyte, and the gametophyte is very small. In seed plants, each female gametophyte, and the spore that gives rise to it, is hidden within the sporophyte and is dependent on it for nutrition. Each male gametophyte consists of from two to four cells enclosed within the protective wall of a pollen grain. The sporophyte of a plant is often described using sexual terms based on the sexuality of the gametophyte it gives rise to. For example, a sporophyte that produces spores that give rise only to male gametophytes may be described as male, even though the sporophyte itself is asexual, producing only spores. Similarly, flowers produced by the sporophyte may be described as unisexual or bisexual, the flower is the characteristic structure concerned with sexual reproduction in flowering plants. Flowers vary enormously in their construction, a complete flower, like that of Ranunculus glaberrimus shown in the figure, has a calyx of outer sepals and a corolla of inner petals. The sepals and petals form the perianth. Next inwards there are numerous stamens, which produce pollen grains, stamens may be called the male parts of a flower and collectively form the androecium. Finally in the middle there are carpels, which at maturity one or more ovules. Carpels may be called the parts of a flower and collectively form the gynoecium
9.
Caterpillar
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Caterpillars /ˈkætərˌpɪlər/ are the larval stage of members of the order Lepidoptera. As with most common names, the application of the word is arbitrary, caterpillars of most species are herbivorous, but not all, some are insectivorous, even cannibalistic. Some feed on other products, for example clothes moths feed on wool. Caterpillars as a rule are voracious feeders and many of them are among the most serious of agricultural pests. In fact many moth species are best known in their caterpillar stages because of the damage cause to fruits and other agricultural produce, whereas the moths are obscure. Conversely, various species of caterpillar are valued as sources of silk, as human or animal food, the origins of the word caterpillar date from the early 16th century. They derive from Middle English catirpel, catirpeller, probably an alteration of Old North French catepelose, cate, cat + pelose, caterpillars have soft bodies that can grow rapidly between moults. Only the head capsule is hardened, the mandibles are tough and sharp for chewing leaves. Behind the mandibles of the caterpillar are the spinnerets, for manipulating silk, antennae are present on either side of the labrum, but small and relatively inconspicuous. Some larvae of the Hymenoptera order can appear like the caterpillars of the Lepidoptera, such larvae are mainly seen in the sawfly family. Caterpillars can be confused with the larvae of sawflies, lepidopteran larvae can be differentiated by, the numbers of pairs of pro-legs, sawfly larvae have 6 while caterpillars have up to 5 pairs. The number of stemmata, the larvae have only two, while a caterpillar has six. The presence of crochets on the prolegs, these are absent in the Symphyta, sawfly larvae have an invariably smooth head capsule with no cleavage lines, while lepidopterous caterpillars bear an inverted Y or V. Many animals feed on caterpillars as they are rich in protein, as a result, caterpillars have evolved various means of defense. The appearance of a caterpillar can often repel a predator, its markings and certain body parts can make it seem poisonous, or bigger in size and thus threatening, some types of caterpillars are indeed poisonous. Caterpillars have evolved defenses against physical conditions such as cold, hot or dry environmental conditions, some Arctic species like Gynaephora groenlandica have special basking and aggregation behaviours apart from physiological adaptations to remain in a dormant state. Many caterpillars are cryptically colored and resemble the plants on which they feed and they may even have parts that mimic plant parts such as thorns. Their size varies from as little as 1 mm to about 75 millimetres, some look like objects in the environment such as bird droppings
10.
Cultivar
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The term cultivar most commonly refers to an assemblage of plants selected for desirable characteristics that are maintained during propagation. More generally, cultivar refers to the most basic classification category of cultivated plants governed by the ICNCP, most cultivars have arisen in cultivation, but a few are special selections from the wild. Popular ornamental garden plants like roses, camellias, daffodils, rhododendrons, trees used in forestry are also special selections grown for their enhanced quality and yield of timber. Cultivars form a part of Liberty Hyde Baileys broader grouping. Cultivar was coined by Bailey and it is regarded as a portmanteau of cultivated and variety. A cultivar is not the same as a variety, a taxonomic rank below subspecies. In recent times, the naming of cultivars has been complicated by the use of statutory plant patents, the International Union for the Protection of New Varieties of Plants offers legal protection of plant cultivars to people or organisations who introduce new cultivars to commerce. UPOV requires that a cultivar be distinct, uniform and stable, to be distinct, it must have characteristics that easily distinguish it from any other known cultivar. To be uniform and stable, the cultivar must retain these characteristics under repeated propagation, a cultivar is given a cultivar name, which consists of the scientific Latin botanical name followed by a cultivar epithet. The cultivar epithet is usually in a vernacular language, for example, the full cultivar name of the King Edward potato is Solanum tuberosum King Edward. The King Edward part of the name is the cultivar epithet, the origin of the term cultivar arises from the need to distinguish between wild plants and those with characteristics that have arisen in cultivation. This distinction dates back to the Greek philosopher Theophrastus, the Father of Botany, botanical historian Alan Morton notes that Theophrastus in his Enquiry into Plants had an inkling of the limits of culturally induced changes and of the importance of genetic constitution. In Species Plantarum, Linnaeus listed all the known to him. Most of the listed by Linnaeus were of garden origin rather than being wild plants. Over time there was an increasing need to distinguish between plants growing in the wild, and those with variations that had produced in cultivation. In the nineteenth century many garden-derived plants were given names, sometimes in Latin. In the twentieth century an improved international terminology was proposed for the classification and it is essentially the equivalent of the botanical variety except in respect to its origin. However, Bailey was never explicit about the etymology of the word, and it has suggested that it is a contraction of the words cultigen and variety
11.
Malus coronaria
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Malus coronaria, also known by the names sweet crabapple or garland crab, is a North American species of Malus. It grows primarily in the Great Lakes Region and in the Ohio Valley, with outlying populations as far away as Alabama, eastern Kansas, Long Island, and Ontario. Malus coronaria often is a shrub with rigid, contorted branches. Its flowering time is two weeks later than that of the domestic apple, and its fragrant fruit clings to the branches on clustered stems long after the leaves have fallen. Malus coronaria var. coronariaMalus coronaria var. dasycalyx list source, Bark, Reddish brown, longitudinally fissured, wood, Reddish brown, sapwood yellow, heavy, close-grained, not strong. Used for the handles of tools and small domestic articles, specific graity,0.7048, weight of cubic foot,43.92. Winter buds, Bright red, obtuse, minute, inner scales grow with the growing shoot, become half an inch long and bright red before they fall. Feather-veined, midrib and primary veins grooved above, prominent beneath and they come out of the bud involute, red bronze, tomentose and downy, when full grown are bright dark green above, paler beneath. Petioles slender, long, often two dark glands near the middle. Stipules filiform, half a long, early deciduous. Flowers, May, June, when leaves are nearly grown, perfect, rose-colored, fragrant, one and one-half inch to two inches across. Borne in five or six-flowered umbels on slender pedicels, calyx, Urn-shaped, downy or tomentose, five-lobed, lobes slender, acute, persistent, imbricate in bud. Corolla, Petals five, rose colored, ob ovate, rounded above, with long claws, undulate or crenelate at margin, inserted on the calyx tube. Pistil, Of five carpels inserted in the bottom of the tube and united into an inferior ovary, styles five, stigma capitate. Fruit, Pome or apple ripening in October, depressed-globular, an inch to an inch and a half in diameter, crowned with calyx lobes and remnant of filaments, yellow green, delightfully fragrant, surface sometimes waxy. Flesh white, delicate and charged with malic acid, seeds two or, by abortion, one in each cell, chestnut brown shining, cotyledons fleshy. They lie under the trees all winter and acquire a yellow color and they seldom begin to rot before spring comes on. List of late spring flowers List of early summer flowers
12.
Species
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In biology, a species is the basic unit of biological classification and a taxonomic rank. A species is defined as the largest group of organisms in which two individuals can produce fertile offspring, typically by sexual reproduction. While this definition is often adequate, looked at more closely it is problematic, for example, with hybridisation, in a species complex of hundreds of similar microspecies, or in a ring species, the boundaries between closely related species become unclear. Other ways of defining species include similarity of DNA, morphology, all species are given a two-part name, a binomial. The first part of a binomial is the genus to which the species belongs, the second part is called the specific name or the specific epithet. For example, Boa constrictor is one of four species of the Boa genus, Species were seen from the time of Aristotle until the 18th century as fixed kinds that could be arranged in a hierarchy, the great chain of being. In the 19th century, biologists grasped that species could evolve given sufficient time, Charles Darwins 1859 book The Origin of Species explained how species could arise by natural selection. Genes can sometimes be exchanged between species by horizontal transfer, and species may become extinct for a variety of reasons. In his biology, Aristotle used the term γένος to mean a kind, such as a bird or fish, a kind was distinguished by its attributes, for instance, a bird has feathers, a beak, wings, a hard-shelled egg, and warm blood. A form was distinguished by being shared by all its members, Aristotle believed all kinds and forms to be distinct and unchanging. His approach remained influential until the Renaissance, when observers in the Early Modern period began to develop systems of organization for living things, they placed each kind of animal or plant into a context. Many of these early delineation schemes would now be considered whimsical, animals likewise that differ specifically preserve their distinct species permanently, one species never springs from the seed of another nor vice versa. In the 18th century, the Swedish scientist Carl Linnaeus classified organisms according to shared physical characteristics and he established the idea of a taxonomic hierarchy of classification based upon observable characteristics and intended to reflect natural relationships. At the time, however, it was widely believed that there was no organic connection between species, no matter how similar they appeared. However, whether or not it was supposed to be fixed, by the 19th century, naturalists understood that species could change form over time, and that the history of the planet provided enough time for major changes. Jean-Baptiste Lamarck, in his 1809 Zoological Philosophy, described the transmutation of species, proposing that a species could change over time, in 1859, Charles Darwin and Alfred Russel Wallace provided a compelling account of evolution and the formation of new species. Darwin argued that it was populations that evolved, not individuals and this required a new definition of species. Darwin concluded that species are what appear to be, ideas
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