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Drosophila Neotestacea
''Drosophila neotestacea'' is a member of the ''testacea'' species group of ''Drosophila''. Testacea species are specialist fruit flies that breed on the fruiting bodies of mushrooms. These flies will choose to breed on psychoactive mushrooms such as the Fly Agaric '' Amanita muscaria''. ''Drosophila neotestacea'' can be found in temperate regions of North America, ranging from the north eastern United States to western Canada. Immunity ''Drosophila neotestacea'' and other mushroom-breeding Drosophila have been studied extensively for their interactions with '' Howardula'' nematode parasites, particularly ''Howardula aoronymphium''. Unlike related species, ''D. neotestacea'' is sterilized by ''H. aoronymphium'' infection. The genetic basis of this susceptibility is unknown, and is nematode-dependent. For instance, a related ''Howardula'' species from Japan does not sterilize ''D. neotestacea'', even though the European and North American ''Howardula'' species do. Moreover, t ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Agaricus
''Agaricus'' is a genus of mushrooms containing both edible and poisonous species, with over 400 members worldwide and possibly again as many disputed or newly-discovered species. The genus includes the common ("button") mushroom (''Agaricus bisporus'') and the field mushroom ('' A. campestris''), the dominant cultivated mushrooms of the West. Members of ''Agaricus'' are characterized by having a fleshy cap or pileus, from the underside of which grow a number of radiating plates or gills, on which are produced the naked spores. They are distinguished from other members of their family, Agaricaceae, by their chocolate-brown spores. Members of ''Agaricus'' also have a stem or stipe, which elevates it above the object on which the mushroom grows, or substrate, and a partial veil, which protects the developing gills and later forms a ring or annulus on the stalk. The genus contains the most widely consumed and best-known mushroom today, '' A. bisporus'', with '' A. arvensis'', ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Frugivorous
A frugivore is an animal that thrives mostly on raw fruits or succulent fruit-like produce of plants such as roots, shoots, nuts and seeds. Approximately 20% of mammalian herbivores eat fruit. Frugivores are highly dependent on the abundance and nutritional composition of fruits. Frugivores can benefit or hinder fruit-producing plants by either dispersing or destroying their seeds through digestion. When both the fruit-producing plant and the frugivore benefit by fruit-eating behavior the interaction is a form of mutualism. Frugivore seed dispersal Seed dispersal is important for plants because it allows their progeny to move away from their parents over time. The advantages of seed dispersal may have led to the evolution of fleshy fruits, which entice animals to consume them and move the plant's seeds from place to place. While many fruit-producing plant species would not disperse far without frugivores, their seeds can usually germinate even if they fall to the ground directly ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Spiroplasma
''Spiroplasma'' is a genus of Mollicutes, a group of small bacteria without cell walls. ''Spiroplasma'' shares the simple metabolism, parasitic lifestyle, fried-egg colony morphology and small genome of other ''Mollicutes'', but has a distinctive helical morphology, unlike ''Mycoplasma''. It has a spiral shape and moves in a corkscrew motion. Many ''Spiroplasma'' are found either in the gut or haemolymph of insects where they can act to manipulate host reproduction, or defend the host as endosymbionts. ''Spiroplasma'' are also disease-causing agents in the phloem of plants. Spiroplasmas are fastidious organisms, which require a rich culture medium. Typically they grow well at 30 °C, but not at 37 °C. A few species, notably '' Spiroplasma mirum'', grow well at 37 °C (human body temperature), and cause cataracts and neurological damage in suckling mice. The best studied species of spiroplasmas are ''Spiroplasma poulsonii'', a reproductive manipulator and defensive ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Drosophila Testacea
''Drosophila testacea'' is a member of the ''testacea'' species group of ''Drosophila''. Testacea species are specialist fruit flies that breed on the fruiting bodies of mushrooms. ''Drosophila testacea'' can be found in temperate regions of Europe, extending to east Asia. ''Drosophila testacea'' and '' Drosophila orientacea'' can produce viable hybrids, though they are separated by geography and behavioural barriers. ''Drosophila testacea'' females will also readily mate with ''Drosophila neotestacea'' males, but viable hybrids are never produced. This hybrid inviability (see Haldane's rule)) may be due to selfish X chromosomes and co-evolved suppressors. Alternately, differences in sex pheromone (e.g. vaccenyl acetate) reception could underlie female readiness and male willingness to copulate. The antimicrobial peptide gene '' Diptericin B'' has been pseudogenized in ''D. testacea'' and likely its sister species ''D. neotestacea''. See also * Drosophila testacea species ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Muller's Ratchet
In evolutionary genetics, Muller's ratchet (named after Hermann Joseph Muller, by analogy with a ratchet effect) is a process through which, in the absence of recombination (especially in an asexual population), an accumulation of irreversible deleterious mutations results. (original paper as cited by, e.g.: ; ) This happens due to the fact that in the absence of recombination, and assuming reverse mutations are rare, offspring bear at least as much mutational load as their parents. Muller proposed this mechanism as one reason why sexual reproduction may be favored over asexual reproduction, as sexual organisms benefit from recombination and consequent elimination of deleterious mutations. The negative effect of accumulating irreversible deleterious mutations may not be prevalent in organisms which, while they reproduce asexually, also undergo other forms of recombination. This effect has also been observed in those regions of the genomes of sexual organisms that do not undergo ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Climate Change
In common usage, climate change describes global warming—the ongoing increase in global average temperature—and its effects on Earth's climate system. Climate change in a broader sense also includes previous long-term changes to Earth's climate. The current rise in global average temperature is more rapid than previous changes, and is primarily caused by humans burning fossil fuels. Fossil fuel use, deforestation, and some agricultural and industrial practices increase greenhouse gases, notably carbon dioxide and methane. Greenhouse gases absorb some of the heat that the Earth radiates after it warms from sunlight. Larger amounts of these gases trap more heat in Earth's lower atmosphere, causing global warming. Due to climate change, deserts are expanding, while heat waves and wildfires are becoming more common. Increased warming in the Arctic has contributed to melting permafrost, glacial retreat and sea ice loss. Higher temperatures are also causing m ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Population Genetics
Population genetics is a subfield of genetics that deals with genetic differences within and between populations, and is a part of evolutionary biology. Studies in this branch of biology examine such phenomena as adaptation, speciation, and population structure. Population genetics was a vital ingredient in the emergence of the modern evolutionary synthesis. Its primary founders were Sewall Wright, J. B. S. Haldane and Ronald Fisher, who also laid the foundations for the related discipline of quantitative genetics. Traditionally a highly mathematical discipline, modern population genetics encompasses theoretical, laboratory, and field work. Population genetic models are used both for statistical inference from DNA sequence data and for proof/disproof of concept. What sets population genetics apart from newer, more phenotypic approaches to modelling evolution, such as evolutionary game theory and adaptive dynamics, is its emphasis on such genetic phenomena as dominance, epi ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Megaselia Nigra
''Megaselia nigra'' is a species of scuttle fly (also called hump-backed flies) in the family Phoridae. ''Megaselia'' species are common pests of mushroom cultivation, attracted by the aroma of developing fungal mycelium. The larvae feed on the developing mycelium of the mushroom, ultimately damaging both the mycelium and gill tissues. ''Megaselia nigra'' can be infected by the symbiotic bacteria ''Spiroplasma'', which may protect its fly host from attack by parasites.Ballinger et al. 2018. https://academic.oup.com/gbe/advance-article/doi/10.1093/gbe/evy272/5255877 See also * ''Megaselia halterata'' * ''Megaselia scalaris The fly ''Megaselia scalaris'' is a member of the order Diptera and the family Phoridae, and it is widely distributed in warm regions of the world. The family members are commonly known as the "humpbacked fly", the "coffin fly", and the "scuttle ...'' References {{Taxonbar, from=Q14121807 Phoridae Insects described in 1830 ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Horizontal Gene Transfer
Horizontal gene transfer (HGT) or lateral gene transfer (LGT) is the movement of genetic material between Unicellular organism, unicellular and/or multicellular organisms other than by the ("vertical") transmission of DNA from parent to offspring (reproduction). HGT is an important factor in the evolution of many organisms. HGT is influencing scientific understanding of higher order evolution while more significantly shifting perspectives on bacterial evolution. Horizontal gene transfer is the primary mechanism for the spread of antibiotic resistance in bacteria, and plays an important role in the evolution of bacteria that can degrade novel compounds such as human-created Bactericide, pesticides and in the evolution, maintenance, and transmission of virulence. It often involves Temperateness (virology), temperate bacteriophages and plasmids. Genes responsible for antibiotic resistance in one species of bacteria can be transferred to another species of bacteria through various m ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Ricin
Ricin ( ) is a lectin (a carbohydrate-binding protein) and a highly potent toxin produced in the seeds of the castor oil plant, ''Ricinus communis''. The median lethal dose (LD50) of ricin for mice is around 22 micrograms per kilogram of body weight via intraperitoneal injection. Oral exposure to ricin is far less toxic. An estimated lethal oral dose in humans is approximately 1 milligram per kilogram of body weight. Ricin was first described by Peter Hermann Stillmark, the founder of lectinology. Biochemistry Ricin is classified as a type 2 ribosome-inactivating protein (RIP). Whereas type 1 RIPs are composed of a single protein chain that possesses catalytic activity, type 2 RIPs, also known as holotoxins, are composed of two different protein chains that form a heterodimeric complex. Type 2 RIPs consist of an A chain that is functionally equivalent to a type 1 RIP, covalently connected by a single disulfide bond to a B chain that is catalytically inactive, but serves to m ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Spiroplasma Poulsonii
''Spiroplasma poulsonii'' are bacteria of the genus ''Spiroplasma'' that are commonly endosymbionts of flies. These bacteria live in the hemolymph (insect blood) of the flies, where they can act as reproductive manipulators or defensive symbionts. Biology ''Spiroplasma poulsonii'' is a maternally transmitted symbiont, meaning it is primarily inherited through the female germ line. This involves the co-option of the fly yolk proteins, which allow the symbiont to enter the developing ovary. In the fly hemolymph, ''S. poulsonii'' feeds on lipids as its primary food source. Male-killing The ''Drosophila melanogaster'' ''S. poulsonii'' strain MSRO kills ''D. melanogaster'' eggs fertilized by Y-bearing sperm. This mode of reproductive manipulation benefits the symbiont as the female fly has a greater reproductive output than males. Thus, by increasing the number of daughters the fly mother produces, the symbiont increases its ability to spread through the increased reproductive outpu ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
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