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Fontanellar Gun
The fontanellar gun is a termite Defense in insects#Chemical defenses, defense mechanism in the form of a horn-like frontal projection (''nasus'') on the head of the soldier caste which is capable of expelling chemical weaponry at a distance, a trait exclusive to the subfamily Nasutitermitinae. It is primarily used to anti-predator adaptation, ward off predators such as ants. Physiology and usage The "gun" is a gland with a duct on the front of the head. It operates by a chemical reaction triggered when the termite contracts its Mandible (insect mouthpart), mandibular muscles. The termite is "able to eject the frontal gland material over a distance of many centimeters". The gland material is forced out through the front of the internal nose and its pores, which covers much of the termite's head. Termites have been shown to be extremely accurate with the gun, even though they are blind. The exact nature of how termites retain such accuracy and are able to orient themselves toward th ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Terpene
Terpenes () are a class of natural products consisting of compounds with the formula (C5H8)n for n ≥ 2. Terpenes are major biosynthetic building blocks. Comprising more than 30,000 compounds, these unsaturated hydrocarbons are produced predominantly by plants, particularly Pinophyta, conifers. In plants, terpenes and terpenoids are important mediators of ecological biological interaction, interactions, while some insects use some terpenes as a form of defense. Other functions of terpenoids include cell growth modulation and plant elongation, light harvesting and photoprotection, and membrane permeability and fluidity control. Terpenes are classified by the number of carbons: monoterpenes (C10), sesquiterpenes (C15), diterpenes (C20), as examples. The terpene alpha-pinene is a major component of the common solvent, turpentine. The one terpene that has major applications is natural rubber (i.e., polyisoprene). The possibility that other terpenes could be used as precursors to pr ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Convergent Evolution
Convergent evolution is the independent evolution of similar features in species of different periods or epochs in time. Convergent evolution creates analogous structures that have similar form or function but were not present in the last common ancestor of those groups. The cladistic term for the same phenomenon is Cladogram#Homoplasies, homoplasy. The recurrent evolution of flight is a classic example, as flying pterygota, insects, birds, pterosaurs, and bats have independently evolved the useful capacity of flight. Functionally similar features that have arisen through convergent evolution are ''analogous'', whereas ''homology (biology), homologous'' structures or traits have a common origin but can have dissimilar functions. Bird, bat, and pterosaur wings are analogous structures, but their forelimbs are homologous, sharing an ancestral state despite serving different functions. The opposite of convergence is divergent evolution, where related species evolve different trai ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Syntermitinae
The Syntermitinae, also known as the ''Mandibulate nasutes'', is a Neotropical subfamily of higher termites represented by 21 genera and 103 species. The soldier caste of members of this subfamily have a conspicuous horn-like projection on the head which is adapted for chemical defense, similar to the fontanellar gun of true nasute termites (Nasutitermitinae). However unlike true nasutes, the mandibles of the soldiers are functional and highly developed, and they are unable to expel their chemical weaponry at a distance – instead relying on direct physical contact. Some genera, such as ''Syntermes'' or '' Labiotermes'', have a highly reduced nasus and in some species it may appear absent altogether. Although the Syntermitinae were once grouped and considered basal within the Nasutitermitinae, they are not closely related with modern cladistic analyses showing Syntermitinae to be a separate lineage that is sister to '' Microcerotermitinae''. It is believed the nasus evolved inde ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Alarm Pheromone
A pheromone () is a secreted or excreted chemical factor that triggers a social response in members of the same species. Pheromones are chemicals capable of acting like hormones outside the body of the secreting individual, to affect the behavior of the receiving individuals. There are ''alarm pheromones'', ''food trail pheromones'', ''sex pheromones'', and many others that affect behavior or physiology. Pheromones are used by many organisms, from basic unicellular prokaryotes to complex multicellular eukaryotes. Their use among insects has been particularly well documented. In addition, some vertebrates, plants and ciliates communicate by using pheromones. The ecological functions and evolution of pheromones are a major topic of research in the field of chemical ecology. Background The portmanteau word "pheromone" was coined by Peter Karlson and Martin Lüscher in 1959, based on the Greek () and (). Pheromones are also sometimes classified as ecto-hormones ("ecto-" meaning ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Pine Resin
A resin is a solid or highly viscous liquid that can be converted into a polymer. Resins may be biological or synthetic in origin, but are typically harvested from plants. Resins are mixtures of organic compounds, predominantly terpenes. Common resins include amber, hashish, frankincense, myrrh and the animal-derived resin, shellac. Resins are used in varnishes, adhesives, food additives, incenses and perfumes. Resins protect plants from insects and pathogens, and are secreted in response to injury. Resins repel herbivores, insects, and pathogens, while the volatile phenolic compounds may attract benefactors such as predators of insects that attack the plant. Composition Most plant resins are composed of terpenes. Specific components are alpha-pinene, beta-pinene, delta-3 carene, and sabinene, the monocyclic terpenes limonene and terpinolene, and smaller amounts of the tricyclic sesquiterpenes, longifolene, caryophyllene, and delta-cadinene. Some resins also contain a hi ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Limonene
Limonene () is a colorless liquid aliphatic hydrocarbon classified as a cyclic monoterpene, and is the major component in the essential oil of citrus fruit peels. The (+)-isomer, occurring more commonly in nature as the fragrance of oranges, is a flavoring agent in food manufacturing. It is also used in chemical synthesis as a precursor to carvone and as a renewables-based solvent in cleaning products. The less common (−)-isomer has a piny, turpentine-like odor, and is found in the edible parts of such plants as caraway, dill, and bergamot orange plants. Limonene takes its name from Italian ''limone'' ("lemon"). Limonene is a chiral molecule, and biological sources produce one enantiomer: the principal industrial source, citrus fruit, contains (+)-limonene (''d''-limonene), which is the (''R'')-enantiomer. (+)-Limonene is obtained commercially from citrus fruits through two primary methods: centrifugal separation or steam distillation. In plants (+)-Limonene ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Myrcene
Myrcene, or β-myrcene, is a terpene, monoterpene. A colorless oil, it occurs widely in essential oils. It is produced mainly semi-synthetically from ''Myrcia'', from which it gets its name. It is an intermediate in the production of several fragrances. A less-common isomeric form, having one of the three alkene units in a different position, is α-myrcene. Production Myrcene is often produced commercially by the pyrolysis (400 °C) of β-pinene, which is obtained from turpentine. It is rarely obtained directly from plants. Plants biosynthesize myrcene via geranyl pyrophosphate (GPP), which isomerizes into linalool, linalyl pyrophosphate. An elimination reaction, releasing the pyrophosphate (OPP) and a proton, completes the conversion. Occurrence It could in principle be extracted from any number of plants, such as verbena or wild thyme, the leaves of which contain up to 40% by weight of myrcene. Many other plants contain myrcene, sometimes in substantial amounts. Some of ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Pinene
Pinene is a collection of unsaturated bicyclic monoterpenes. Two geometric isomers of pinene are found in nature, α-pinene and β-pinene. Both are chiral. As the name suggests, pinenes are found in pines. Specifically, pinene is the major component of the liquid extracts of conifers. Pinenes are also found in many non-coniferous plants such as camphorweed ('' Heterotheca'') and big sagebrush ('' Artemisia tridentata''). Isomers Biosynthesis α-Pinene and β-pinene are both produced from geranyl pyrophosphate, via cyclisation of linaloyl pyrophosphate followed by loss of a proton from the carbocation equivalent. Researchers at the Georgia Institute of Technology and the Joint BioEnergy Institute have been able to synthetically produce pinene with a bacterium. Plants Alpha-pinene is the most widely encountered terpenoid in nature and is highly repellent to insects. Alpha-pinene appears in conifers and numerous other plants. Pinene is a major component of the essent ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Tenuirostritermes Tenuirostris
''Tenuirostritermes'' is a genus of termites in the family Termitidae Termitidae is the largest family of termites consisting of 2,125 described species of which are commonly known as the higher termites. They are evolutionarily the most specialised termite group, with their highly compartmentalized hindgut lackin .... There are about five described species in ''Tenuirostritermes''. Species These five species belong to the genus ''Tenuirostritermes'': * '' Tenuirostritermes briciae'' (Snyder, 1922) * '' Tenuirostritermes cinereus'' (Buckley, 1862) * '' Tenuirostritermes incisus'' (Snyder, 1922) * '' Tenuirostritermes strenuus'' (Hagen, 1860) * '' Tenuirostritermes tenuirostris'' (Desneux, 1904) References Further reading * Termites Articles created by Qbugbot {{termite-stub ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Termite
Termites are a group of detritivore, detritophagous Eusociality, eusocial cockroaches which consume a variety of Detritus, decaying plant material, generally in the form of wood, Plant litter, leaf litter, and Humus, soil humus. They are distinguished by their moniliform antennae and the soft-bodied, unpigmented worker caste for which they have been commonly termed "white ants"; however, they are not ants but highly Apomorphy and synapomorphy, derived cockroaches. About 2,997 extant species are currently described, 2,125 of which are members of the family Termitidae. Termites comprise the infraorder Isoptera, or alternatively the Taxonomic rank#All ranks, epifamily Termitoidae, within the order Blattodea (the cockroaches). Termites were once classified in a separate Order (biology), order from cockroaches, but recent phylogenetic studies indicate that they evolved from cockroaches, as they are deeply nested within the group, and the sister group to wood-eating cockroaches of t ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
A Journal Of Entomology
A, or a, is the first letter and the first vowel letter of the Latin alphabet, used in the modern English alphabet, and others worldwide. Its name in English is '' a'' (pronounced ), plural ''aes''. It is similar in shape to the Ancient Greek letter alpha, from which it derives. The uppercase version consists of the two slanting sides of a triangle, crossed in the middle by a horizontal bar. The lowercase version is often written in one of two forms: the double-storey and single-storey . The latter is commonly used in handwriting and fonts based on it, especially fonts intended to be read by children, and is also found in italic type. In English, '' a'' is the indefinite article, with the alternative form ''an''. Name In English, the name of the letter is the ''long A'' sound, pronounced . Its name in most other languages matches the letter's pronunciation in open syllables. History The earliest known ancestor of A is ''aleph''—the first letter of the Phoenician ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
