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Dart Sac
A love dart (also known as a gypsobelum, shooting darts, or just as darts) is a sharp, calcareous or chitinous dart which some hermaphroditic land snails and slugs create. Love darts are both formed and stored internally in a dart sac. These darts are made in sexually mature animals only, and are used as part of the sequence of events during courtship, before actual mating takes place. Darts are quite large compared to the size of the animal: in the case of the semi-slug genus ''Parmarion'', the length of a dart can be up to one fifth that of the semi-slug's foot. The process of using love darts in snails is a form of sexual selection. Prior to copulation, each of the two snails (or slugs) attempts to "shoot" one (or more) darts into the other snail (or slug). There is no organ to receive the dart; this action is more analogous to stabbing, or to being shot with an arrow or flechette. The dart does not fly through the air to reach its target, but is "fired" as a contact ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Monachoides Vicinus Dart Lateral
''Monachoides'' is a genus of air-breathing land snails, terrestrial pulmonate gastropod mollusks in the family Hygromiidae, the hairy snails and their allies. MolluscaBase eds. (2021). MolluscaBase. Monachoides Gude & B. B. Woodward, 1921. Accessed through: World Register of Marine Species at: http://www.marinespecies.org/aphia.php?p=taxdetails&id=996512 on 2021-08-12 Some species of snails in this genus create and use love darts as part of their mating behavior. Species The following species are recognised within the genus ''Monachoides'': * '' Monachoides bacescui'' (Grossu, 1979) * †'' Monachoides barotiana'' Marinescu, 1975 * '' Monachoides fallax'' (Wagner, 1914) * '' Monachoides incarnatus'' (Müller, 1774) - the type species In zoological nomenclature, a type species (''species typica'') is the species name with which the name of a genus or subgenus is considered to be permanently taxonomically associated, i.e., the species that contains the biological type specimen ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Flechette
A flechette ( ) is a pointed steel projectile with a vaned tail for stable flight. The name comes from French , "little arrow" or "dart", and sometimes retains the acute accent in English: fléchette. They have been used as ballistic weapons since World War I. Delivery systems and methods of launching flechettes vary, from a single shot, to thousands in a single explosive round. The use of flechettes as antipersonnel weapons has been controversial. Air-dropped During World War I, flechettes were dropped from aircraft to attack infantry and were able to pierce helmets. Later the U.S. used Lazy Dog bombs, which are small, unguided kinetic projectiles typically about in length, in diameter, and weighing about . The weapons were designed to be dropped from an aircraft. They contained no explosive charge but as they fell they developed significant kinetic energy making them lethal and able to easily penetrate soft cover such as jungle canopy, several inches of sand or light armo ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Helix (genus)
''Helix'' is a genus of large, air-breathing land snails native to Europe and the Mediterranean region. They are the type genus of the family Helicidae, and are among the first animal genera described by Carl Linnaeus.Rosenberg, G.; Bouchet, P. (2014). ''Helix'' Linnaeus, 1758. Accessed through: World Register of Marine Species at http://www.marinespecies.org/aphia.php?p=taxdetails&id=153970 on 2015-02-24 Members of the genus first appeared during the Oligocene. Like most land snails, ''Helix'' species are hermaphroditic, and like other helicids, a Courtship, courting pair will impale each other with hormone-rich love darts prior to exchanging sperm. Well-known species include ''Helix pomatia'' (Roman snail, Burgundy snail, or edible snail) and ''Helix lucorum'' (Turkish snail). ''Cornu aspersum'' (garden snail) – another well-known helicid – was originally described as a member of ''Helix'' (as "''Helix aspersa''"), but the prevailing classification places it as the sole memb ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Courting
Courtship is the period wherein some couples get to know each other prior to a possible marriage. Courtship traditionally may begin after a betrothal and may conclude with the celebration of marriage. A courtship may be an informal and private matter between two people or may be a public affair, or a formal arrangement with family approval. Traditionally, in the case of a formal engagement, it is the role of a male to actively "court" or "woo" a female, thus encouraging her to understand him and her receptiveness to a marriage proposal. Duration The average duration of courtship varies considerably throughout the world. Furthermore, there is vast individual variation between couples. Courtship may be completely omitted, as in cases of some arranged marriages where the couple do not meet before the wedding. In the United Kingdom, a poll of 3,000 [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Mating
In biology, mating is the pairing of either opposite-sex or hermaphroditic organisms for the purposes of sexual reproduction. ''Fertilization'' is the fusion of two gametes. ''Copulation'' is the union of the sex organs of two sexually reproducing animals for insemination and subsequent internal fertilization. Mating may also lead to external fertilization, as seen in amphibians, fishes and plants. For most species, mating is between two individuals of opposite sexes. However, for some hermaphroditic species, copulation is not required because the parent organism is capable of self-fertilization (autogamy); for example, banana slugs. The term ''mating'' is also applied to related processes in bacteria, archaea and viruses. Mating in these cases involves the pairing of individuals, accompanied by the pairing of their homologous chromosomes and then exchange of genomic information leading to formation of recombinant progeny (see mating systems). Animals For animals, mating ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Helix Pomatia Head Mating
A helix () is a shape like a corkscrew or spiral staircase. It is a type of smooth space curve with tangent lines at a constant angle to a fixed axis. Helices are important in biology, as the DNA molecule is formed as two intertwined helices, and many proteins have helical substructures, known as alpha helices. The word ''helix'' comes from the Greek word ''ἕλιξ'', "twisted, curved". A "filled-in" helix – for example, a "spiral" (helical) ramp – is a surface called ''helicoid''. Properties and types The ''pitch'' of a helix is the height of one complete helix turn, measured parallel to the axis of the helix. A double helix consists of two (typically congruent) helices with the same axis, differing by a translation along the axis. A circular helix (i.e. one with constant radius) has constant band curvature and constant torsion. A '' conic helix'', also known as a ''conic spiral'', may be defined as a spiral on a conic surface, with the distance to the apex an ex ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Garden Snails And Love Dart
A garden is a planned space, usually outdoors, set aside for the cultivation, display, and enjoyment of plants and other forms of nature. The single feature identifying even the wildest wild garden is ''control''. The garden can incorporate both natural and artificial materials. Gardens often have design features including statuary, follies, pergolas, trellises, stumperies, dry creek beds, and water features such as fountains, ponds (with or without fish), waterfalls or creeks. Some gardens are for ornamental purposes only, while others also produce food crops, sometimes in separate areas, or sometimes intermixed with the ornamental plants. Food-producing gardens are distinguished from farms by their smaller scale, more labor-intensive methods, and their purpose (enjoyment of a hobby or self-sustenance rather than producing for sale, as in a market garden). Flower gardens combine plants of different heights, colors, textures, and fragrances to create interest and delight the ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Sewing Needle
A sewing needle, used for hand-sewing, is a long slender tool with a pointed tip at one end and a hole (or ''eye'') to hold the sewing thread. The earliest needles were made of bone or wood; modern needles are manufactured from high carbon steel wire and are nickel- or 18K gold-plated for corrosion resistance. High quality embroidery needles are plated with two-thirds platinum and one-third titanium alloy. Traditionally, needles have been kept in needle books or needlecases which have become objects of adornment. Sewing needles may also be kept in an étui, a small box that held needles and other items such as scissors, pencils and tweezers. Types of hand sewing needles Hand sewing needles come in a variety of types/classes designed according to their intended use and in a variety of sizes within each type. * Sharp needles: used for general hand sewing; built with a sharp point, a round eye, and are of medium length. Those with a double-eyes are able to carry two strands of ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Harpoon
A harpoon is a long spear-like instrument and tool used in fishing, whaling, seal hunting, sealing, and other marine hunting to catch and injure large fish or marine mammals such as seals and whales. It accomplishes this task by impaling the target animal and securing it with barb or toggling claws, allowing the fishermen to use a rope or chain attached to the projectile to catch the animal. A harpoon can also be used as a weapon. Certain harpoons are made with different builds to perform better with the type of target being aimed at. For example, the Inuit have short, fixed foreshaft harpoons for hunting seals at their breathing holes while loose shafted ones are made for attaching to the game thrown at. History In the 1990s, harpoon points, known as the Semliki harpoons or the Katanda harpoons, were found in the Katanda_Territory, Katanda region in Zaire (called the Democratic Republic of the Congo today). As the earliest known harpoons, these weapons were made and used 90, ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Allomone
An allomone (from Ancient Greek ' "other" and pheromone) is a type of semiochemical produced and released by an individual of one species that affects the behaviour of a member of another species to the benefit of the originator but not the receiver. Production of allomones is a common form of defense against predators, particularly by plant species against insect herbivores. In addition to defense, allomones are also used by organisms to obtain their prey or to hinder any surrounding competitors. Many insects have developed ways to defend against these plant defenses (in an evolutionary arms race). One method of adapting to allomones is to develop a positive reaction to them; the allomone then becomes a kairomone. Others alter the allomones to form pheromones or other hormones, and yet others adopt them into their own defensive strategies, for example by regurgitating them when attacked by an insectivorous insect. A third class of allelochemical (chemical used in interspecif ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Reproductive
The reproductive system of an organism, also known as the genital system, is the biological system made up of all the anatomical organs involved in sexual reproduction. Many non-living substances such as fluids, hormones, and pheromones are also important accessories to the reproductive system. Unlike most organ systems, the sexes of differentiated species often have significant differences. These differences allow for a combination of genetic material between two individuals, which allows for the possibility of greater genetic fitness of the offspring. Reproductive System 2001 Body Guide powered by Adam Animals In mammals, the major organs of the reproductive system include the external |
