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Paragordius Tricuspidatus
''Paragordius tricuspidatus'' belongs to the phylum Nematomorpha, and is known for manipulating the behavior of its host, the cricket ''Nemobius sylvestris''. In its larval stage, the worm is microscopic, but grows into a large worm () inside its host after accidental ingestion since their eggs are laid at the edge of the water by rivers where crickets frequently reside. Upon ingestion, the worm nourishes upon its host and fills the entire body cavity of the cricket, until maturation, when the parasitic worm is ready to exit into water to complete its life cycle, maximizing its reproductive success. The worm induces a peculiar behavior on its cricket host, which causes it to leap into water whereby the parasitic worm can slither out and find its mate, while the cricket often perishes. Should the cricket be preyed upon by a predator, such as a fish or frog, the worm has the ability to not only escape from the host's body but also the predator's digestive system. The worm emerges fr ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Nematomorpha
Nematomorpha (sometimes called Gordiacea, and commonly known as horsehair worms, hairsnakes, or Gordian worms) are a phylum of parasitoid animals superficially similar to nematode worms in morphology, hence the name. Most species range in size from long, reaching 2 metres in extreme cases, and in diameter. Horsehair worms can be discovered in damp areas, such as watering troughs, swimming pools, streams, puddles, and cisterns. The adult worms are free-living, but the larvae are parasitic on arthropods, such as beetles, cockroaches, mantises, orthopterans, and crustaceans. About 351 freshwater species are known and a conservative estimate suggests that there may be about 2000 freshwater species worldwide. The name "Gordian" stems from the legendary Gordian knot. This relates to the fact that nematomorphs often coil themselves in tight balls that resemble knots. Description and biology Nematomorphs possess an external cuticle without cilia. Internally, they have only longitudin ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Behavior-altering Parasite
Behavior-altering parasites are parasites with two or more hosts, capable of causing changes in the behavior of one of their Host (biology), hosts to enhance their Transmission (medicine), transmission, sometimes directly affecting the hosts' decision-making and behavior control mechanisms. They do this by making the intermediate host, where they may reproduce asexually, more likely to be eaten by a predator at a higher trophic level which becomes the definitive host where the parasite reproduces sexually; the mechanism is therefore sometimes called parasite increased trophic facilitation or parasite increased trophic transmission. Examples can be found in bacteria, protozoa, viruses, and animals. Parasites may also alter the host behaviour to increase protection of the parasites or their offspring; the term bodyguard manipulation is used for such mechanisms. Among the behavioral changes caused by parasites is carelessness, making their hosts easier prey.Moore, J. (2002). Parasites ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Cricket (insect)
Crickets are orthopteran insects which are related to bush crickets, and, more distantly, to grasshoppers. In older literature, such as Imms,Imms AD, rev. Richards OW & Davies RG (1970) ''A General Textbook of Entomology'' 9th Ed. Methuen 886 pp. "crickets" were placed at the family level (''i.e.'' Gryllidae), but contemporary authorities including Otte now place them in the superfamily Grylloidea. The word has been used in combination to describe more distantly related taxa in the suborder Ensifera, such as king crickets and mole crickets. Crickets have mainly cylindrically-shaped bodies, round heads, and long antennae. Behind the head is a smooth, robust pronotum. The abdomen ends in a pair of long cerci; females have a long, cylindrical ovipositor. Diagnostic features include legs with 3-segmented tarsi; as with many Orthoptera, the hind legs have enlarged femora, providing power for jumping. The front wings are adapted as tough, leathery elytra, and some crickets ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Nemobius Sylvestris
''Nemobius sylvestris'', the wood cricket, is a flightless species of cricket in the family Gryllidae. It is native to Western Europe and North Africa but uncommon in Britain. Description This cricket is a small, dark brown, ground-dwelling, grasshopper-like insect with long, thread-like antennae. It grows to about . Neither males nor females have hind wings; in males the fore-wings extend half way along the abdomen, while in females, the fore-wings are reduced to rounded stubs. Females also have a long ovipositor at the tip of the abdomen. Distribution and habitat The wood cricket is native to Europe and North Africa. Its range includes Western, Central and Southern Europe, Corsica, Algeria and Morocco. The natural habitat of this species is forest edges and woodland clearings, where it is associated with oak, beech, hazel and holly trees and with bracken. It thrives among the leaf litter in warm, sunny spots. It is uncommon in Britain, with separate populations in the New F ... [...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 immobil ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Behavioral Ecology (journal)
''Behavioral Ecology'' is a bimonthly peer-reviewed scientific journal published by Oxford University Press on behalf of the International Society for Behavioral Ecology. The journal was established in 1990. Scope ''Behavioral Ecology'' publishes empirical and theoretical papers on a broad range of topics related to behavioural ecology, including ethology, sociobiology, evolution, and ecology of behaviour. The journal includes research at the levels of the individual, population, and community on various organisms such as vertebrates, invertebrates, and plants. According to the ''Journal Citation Reports'', the journal has a 2020 impact factor The impact factor (IF) or journal impact factor (JIF) of an academic journal is a scientometric index calculated by Clarivate that reflects the yearly mean number of citations of articles published in the last two years in a given journal, as ... of 2.671, ranking it 22nd out of 175 journals in the category "Zoology". Artic ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Parasitic Worm
Parasitic worms, also known as helminths, are large Parasitism#Basic concepts, macroparasites; adults can generally be seen with the naked eye. Many are intestinal worms that are soil-transmitted helminth, soil-transmitted and intestinal parasite infection, infect the gastrointestinal tract. Other parasitic worms such as schistosomes reside in blood vessels. Some parasitic worms, including leeches and monogeneans, are ectoparasites thus, they are not classified as helminths, which are Parasitism#Basic concepts, endoparasites. Parasitic worms live in and feed in living host (biology), hosts. They receive nourishment and protection while disrupting their hosts' ability to absorb nutrients. This can cause weakness and disease in the host, and poses a global health and economic problem. Parasitic worms cannot reproduce entirely within their host's body; they have a life cycle that includes some stages that need to take place outside of the host. Helminths are able to survive in the ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
International Journal For Parasitology
The ''International Journal for Parasitology'' is an international medical journal published for the Australian Society for Parasitology by Elsevier. The journal includes original research articles, reviews, and commentary relating to parasites Parasitism is a Symbiosis, close relationship between species, where one organism, the parasite, lives on or inside another organism, the Host (biology), host, causing it some harm, and is Adaptation, adapted structurally to this way of lif ... and their host interactions. External links * Australian Society for Parasitology Parasitology journals Publications established in 1971 Elsevier academic journals English-language journals Journals published between 13 and 25 times per year {{med-journal-stub ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Spinochordodes Tellinii
''Spinochordodes tellinii'' is a parasitic nematomorph hairworm whose larvae develop in grasshoppers and crickets. This parasite is able to influence its host's behavior: once the parasite is grown, it causes its grasshopper host to jump into water, where the grasshopper will likely drown. The parasite then leaves its host; the adult worm lives and reproduces in water. ''S. tellinii'' does not influence its host to actively seek water over large distances, but only when it is already close to water. The microscopic larvae are ingested by their insect hosts and develop inside them into worms that can be three to four times longer than the host. The precise molecular mechanism underlying the modification of the host's behaviour is not yet known. A study in 2005 indicated that grasshoppers which contain the parasite express, or create, different proteins in their brains compared to uninfected grasshoppers. Some of these proteins have been linked to neurotransmitter activity, ot ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Central Nervous System
The central nervous system (CNS) is the part of the nervous system consisting primarily of the brain and spinal cord. The CNS is so named because the brain integrates the received information and coordinates and influences the activity of all parts of the bodies of bilaterally symmetric and triploblastic animals—that is, all multicellular animals except sponges and diploblasts. It is a structure composed of nervous tissue positioned along the rostral (nose end) to caudal (tail end) axis of the body and may have an enlarged section at the rostral end which is a brain. Only arthropods, cephalopods and vertebrates have a true brain (precursor structures exist in onychophorans, gastropods and lancelets). The rest of this article exclusively discusses the vertebrate central nervous system, which is radically distinct from all other animals. Overview In vertebrates, the brain and spinal cord are both enclosed in the meninges. The meninges provide a barrier to chemicals dissolv ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Wnt Signaling Pathway
The Wnt signaling pathways are a group of signal transduction pathways which begin with proteins that pass signals into a cell through cell surface receptors. The name Wnt is a portmanteau created from the names Wingless and Int-1. Wnt signaling pathways use either nearby cell-cell communication (paracrine) or same-cell communication (autocrine). They are highly evolutionarily conserved in animals, which means they are similar across animal species from fruit flies to humans. Three Wnt signaling pathways have been characterized: the canonical Wnt pathway, the noncanonical planar cell polarity pathway, and the noncanonical Wnt/calcium pathway. All three pathways are activated by the binding of a Wnt-protein ligand to a Frizzled family receptor, which passes the biological signal to the Dishevelled protein inside the cell. The canonical Wnt pathway leads to regulation of gene transcription, and is thought to be negatively regulated in part by the SPATS1 gene. The noncanonical plana ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Molecular Mimicry
Molecular mimicry is defined as the theoretical possibility that sequence similarities between foreign and self-peptides are sufficient to result in the cross-activation of autoreactive T or B cells by pathogen-derived peptides. Despite the prevalence of several peptide sequences which can be both foreign and self in nature, a single antibody or TCR (T cell receptor) can be activated by just a few crucial residues which stresses the importance of structural homology in the theory of molecular mimicry. Upon the activation of B or T cells, it is believed that these "peptide mimic" specific T or B cells can cross-react with self-epitopes, thus leading to tissue pathology (autoimmunity). Molecular mimicry is a phenomenon that has been just recently discovered as one of several ways in which autoimmunity can be evoked. A molecular mimicking event is, however, more than an epiphenomenon despite its low statistical probability of occurring and these events have serious implications in th ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
