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Kairomone
A kairomone (a coinage using the Greek καιρός ''opportune moment'', paralleling pheromone"kairomone, n.". OED Online. September 2012. Oxford University Press. http://www.oed.com/view/Entry/241005?redirectedFrom=kairomone (accessed 3 October 2012).) is a semiochemical, emitted by an organism, which mediates interspecific interactions in a way that benefits an individual of another species which receives it and harms the emitter. This "eavesdropping" is often disadvantageous to the producer (though other benefits of producing the substance may outweigh this cost, hence its persistence over evolutionary time). The kairomone improves the fitness of the recipient and in this respect differs from an allomone (which is the opposite: it benefits the producer and harms the receiver) and a synomone (which benefits both parties). The term is mostly used in the field of entomology (the study of insects). Two main ecological cues are provided by kairomones; they generally either indica ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Semiochemical
A semiochemical, from the Greek σημεῖον (''semeion''), meaning "signal", is a chemical substance or mixture released by an organism that affects the behaviors of other individuals. Semiochemical communication can be divided into two broad classes: communication between individuals of the same species (intraspecific) or communication between different species ( interspecific). It is usually used in the field of chemical ecology to encompass pheromones, allomones, kairomones, attractants and repellents. Many insects, including parasitic insects, use semiochemicals. Pheromones are intraspecific signals that aid in finding mates, food and habitat resources, warning of enemies, and avoiding competition. Interspecific signals known as allomones and kairomones have similar functions. In nature Pheromone A pheromone (from Greek ''phero'' "to bear" + ''hormone'' from Greek – "impetus") is a secreted or excreted chemical factor that triggers a social response in members ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Daphnia
''Daphnia'' is a genus of small planktonic crustaceans, in length. ''Daphnia'' are members of the order Anomopoda, and are one of the several small aquatic crustaceans commonly called water fleas because their saltatory swimming style resembles the movements of fleas. ''Daphnia'' spp. live in various aquatic environments ranging from acidic swamps to freshwater lakes and ponds. The two most commonly found species of ''Daphnia'' are '' D. pulex'' (small and most common) and '' D. magna'' (large). They are often associated with a related genus in the order Cladocera: '' Moina'', which is in the Moinidae family instead of the Daphniidae, and is much smaller than ''D. pulex'' (roughly half the maximum length). Appearance and characteristics The body of a ''Daphnia'' species is usually long, and is divided into segments, although this division is not visible. The head is fused, and is generally bent down towards the body with a visible notch separating the ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Predator-induced Polyphenism
A polyphenic trait is a trait for which multiple, discrete phenotypes can arise from a single genotype as a result of differing environmental conditions. It is therefore a special case of phenotypic plasticity. There are several types of polyphenism in animals, from having sex determined by the environment to the castes of honey bees and other social insects. Some polyphenisms are seasonal, as in some butterflies which have different patterns during the year, and some Arctic animals like the snowshoe hare and Arctic fox, which are white in winter. Other animals have predator-induced or resource polyphenisms, allowing them to exploit variations in their environment. Some nematode worms can develop either into adults or into resting dauer larvae according to resource availability. Definition upright=1.2, Polyphenism in termites A : Primary king B : Primary queen C : Secondary queen D : Tertiary queen E : Soldiers F : Worker A polyphenism is the occurr ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Bark Beetle
A bark beetle is the common name for the subfamily of beetles Scolytinae. Previously, this was considered a distinct family (Scolytidae), but is now understood to be a specialized clade of the "true weevil" family ( Curculionidae). Although the term "bark beetle" refers to the fact that many species feed in the inner bark (phloem) layer of trees, the subfamily also has many species with other lifestyles, including some that bore into wood, feed in fruit and seeds, or tunnel into herbaceous plants. Well-known species are members of the type genus '' Scolytus'', namely the European elm bark beetle ''S. multistriatus'' and the large elm bark beetle ''S. scolytus'', which like the American elm bark beetle '' Hylurgopinus rufipes'', transmit Dutch elm disease fungi (''Ophiostoma''). The mountain pine beetle ''Dendroctonus ponderosae'', southern pine beetle '' Dendroctonus frontalis'', and their near relatives are major pests of conifer forests in North America. A similarly aggr ... [...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 interspeci ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Neologism
A neologism Greek νέο- ''néo''(="new") and λόγος /''lógos'' meaning "speech, utterance"] is a relatively recent or isolated term, word, or phrase that may be in the process of entering common use, but that has not been fully accepted into mainstream language. Neologisms are often driven by changes in culture and technology. In the process of language formation, neologisms are more mature than '' protologisms''. A word whose development stage is between that of the protologism (freshly coined) and neologism (new word) is a ''prelogism''. Popular examples of neologisms can be found in science, fiction (notably science fiction), films and television, branding, literature, jargon, cant, linguistics, the visual arts, and popular culture. Former examples include ''laser'' (1960) from Light Amplification by Stimulated Emission of Radiation; ''robot'' (1941) from Czech writer Karel Čapek's play '' R.U.R. (Rossum's Universal Robots)''; and '' agitprop'' (1930) (a portmantea ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Iridomyrmex Purpureus
''Iridomyrmex'' is a genus of ants called rainbow ants (referring to their blue-green iridescent sheen) first described by Austrian entomologist Gustav Mayr in 1862. He placed the genus in the subfamily Dolichoderinae of the family Formicidae. It has 79 described species and five fossil species. Most of these ants are native to Australia; others are found in Asia and Oceania, and they have been introduced to Brazil, New Zealand, and the United Arab Emirates. Fossil species are known from China, France, and the United States. These ants are known to be an ecologically dominant and important group of ants, but they are sometimes regarded as pests because they disturb soil and enter human houses. Farmers in rural Australia place animal carcasses on meat ant ('' I. purpureus'') mounds as a method of disposing of them; meat ants consume the carcass and reduce it to bones in a matter of weeks. Meat ants also engage in ritualised fighting, which helps prevent casualties and solve ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Spider
Spiders (order Araneae) are air-breathing arthropods that have eight legs, chelicerae with fangs generally able to inject venom, and spinnerets that extrude silk. They are the largest order of arachnids and rank seventh in total species diversity among all orders of organisms. Spiders are found worldwide on every continent except for Antarctica, and have become established in nearly every land habitat. , 50,356 spider species in 132 families have been recorded by taxonomists. However, there has been debate among scientists about how families should be classified, with over 20 different classifications proposed since 1900. Anatomically, spiders (as with all arachnids) differ from other arthropods in that the usual body segments are fused into two tagmata, the cephalothorax or prosoma, and the opisthosoma, or abdomen, and joined by a small, cylindrical pedicel, however, as there is currently neither paleontological nor embryological evidence that spiders ever had a sep ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Morphology (biology)
Morphology is a branch of biology dealing with the study of the form and structure of organisms and their specific structural features. This includes aspects of the outward appearance ( shape, structure, colour, pattern, size), i.e. external morphology (or eidonomy), as well as the form and structure of the internal parts like bones and organs, i.e. internal morphology (or anatomy). This is in contrast to physiology, which deals primarily with function. Morphology is a branch of life science dealing with the study of gross structure of an organism or taxon and its component parts. History The etymology of the word "morphology" is from the Ancient Greek (), meaning "form", and (), meaning "word, study, research". While the concept of form in biology, opposed to function, dates back to Aristotle (see Aristotle's biology), the field of morphology was developed by Johann Wolfgang von Goethe (1790) and independently by the German anatomist and physiologist Karl Fr ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Larva
A larva (; plural larvae ) is a distinct juvenile form many animals undergo before metamorphosis into adults. Animals with indirect development such as insects, amphibians, or cnidarians typically have a larval phase of their life cycle. The larva's appearance is generally very different from the adult form (''e.g.'' caterpillars and butterflies) including different unique structures and organs that do not occur in the adult form. Their diet may also be considerably different. Larvae are frequently adapted to different environments than adults. For example, some larvae such as tadpoles live almost exclusively in aquatic environments, but can live outside water as adult frogs. By living in a distinct environment, larvae may be given shelter from predators and reduce competition for resources with the adult population. Animals in the larval stage will consume food to fuel their transition into the adult form. In some organisms like polychaetes and barnacles, adults are im ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Leptodora
''Leptodora'' is a genus containing two species of large, nearly transparent predatory water fleas. They grow up to long, with two large antennae used for swimming and a single compound eye. The legs are used to catch copepods that it comes into contact with by chance. ''Leptodora kindtii'' is found in temperate lakes across the Northern Hemisphere and is probably the only cladoceran ever described in a newspaper; ''L. richardi'' is only known from eastern Russia. For most of the year, ''Leptodora'' reproduces parthenogenetically, with males only appearing late in the season, to produce winter eggs which hatch the following spring. ''Leptodora'' is the only genus in its family, the Leptodoridae, and suborder, Haplopoda. Description Adults of ''Leptodora'' are the largest planktonic cladocerans native to North America; reports vary concerning the largest size, but adult females typically grow to long, but with some reports of females up to . They are about 98% transparent, as a ... [...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 anim ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
