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Ambrosia Beetles
Ambrosia beetles are beetles of the weevil subfamilies Scolytinae and Platypodinae (Coleoptera, Curculionidae), which live in nutritional symbiosis with ambrosia fungi. The beetles excavate tunnels in dead or stressed trees into which they introduce fungal gardens, their sole source of nutrition. After landing on a suitable tree, an ambrosia beetle excavates a tunnel in which it releases its fungal symbiont. The fungus penetrates the plant's xylem tissue, extracts nutrients from it, and concentrates the nutrients on and near the surface of the beetle gallery. Ambrosia fungi are typically poor wood degraders, and instead utilize less demanding nutrients. Symbiotic fungi produce and detoxify ethanol, which is an attractant for ambrosia beetles and likely prevents growth of antagonistic pathogens and selects for other beneficial symbionts. The majority of ambrosia beetles colonize xylem (sapwood and/or heartwood) of recently dead trees, but some colonize stressed trees that are still ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Weevil
Weevils are beetles belonging to the superfamily Curculionoidea, known for their elongated snouts. They are usually small – less than in length – and herbivorous. Approximately 97,000 species of weevils are known. They belong to several families, with most of them in the family Curculionidae (the true weevils). It also includes bark beetles, which while morphologically dissimilar to other weevils in lacking the distinctive snout, is a subfamily of Curculionidae. Some other beetles, although not closely related, bear the name "weevil", such as the leaf beetle subfamily Bruchinae, known as "bean weevils", or the biscuit weevil (''Stegobium paniceum''), which belongs to the family Ptinidae. Many weevils are considered pests because of their ability to damage and kill crops. The grain or wheat weevil (''Sitophilus granarius'') damages stored grain, as does the maize weevil (''Sitophilus zeamais''), among others. The boll weevil (''Anthonomus grandis'') attacks cotton crop ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Isoptera
Termites are a group of detritophagous eusocial cockroaches which consume a variety of decaying plant material, generally in the form of wood, leaf litter, and 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 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 epifamily Termitoidae, within the order Blattodea (the cockroaches). Termites were once classified in a separate 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 the genus '' Cryptocercus''. Previous estimates suggested the divergence took place during the Jurassic or Triassic. More ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Mycelium
Mycelium (: mycelia) is a root-like structure of a fungus consisting of a mass of branching, thread-like hyphae. Its normal form is that of branched, slender, entangled, anastomosing, hyaline threads. Fungal colonies composed of mycelium are found in and on soil and many other substrates. A typical single spore germinates into a monokaryotic mycelium, which cannot reproduce sexually; when two compatible monokaryotic mycelia join and form a dikaryotic mycelium, that mycelium may form fruiting bodies such as mushrooms. A mycelium may be minute, forming a colony that is too small to see, or may grow to span thousands of acres as in '' Armillaria''. Through the mycelium, a fungus absorbs nutrients from its environment. It does this in a two-stage process. First, the hyphae secrete enzymes onto or into the food source, which break down biological polymers into smaller units such as monomers. These monomers are then absorbed into the mycelium by facilitated diffusion and ac ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Larva
A larva (; : larvae ) is a distinct juvenile form many animals undergo before metamorphosis into their next life stage. Animals with indirect development such as insects, some arachnids, amphibians, or cnidarians typically have a larval phase of their life cycle. A 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. In the case of smaller primitive arachnids, the larval stage differs by having three instead of four pairs of legs. 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 lar ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Palearctic Realm
The Palearctic or Palaearctic is a biogeographic realm of the Earth, the largest of eight. Confined almost entirely to the Eastern Hemisphere, it stretches across Europe and Asia, north of the foothills of the Himalayas, and North Africa. The realm consists of several bioregions: the Mediterranean Basin; North Africa; North Arabia; Western, Central and East Asia. The Palaearctic realm also has numerous rivers and lakes, forming several freshwater ecoregions. Both the eastern and westernmost extremes of the Paleartic span into the Western Hemisphere, including Cape Dezhnyov in Chukotka Autonomous Okrug to the east and Iceland to the west. The term was first used in the 19th century, and is still in use as the basis for zoogeographic classification. History In an 1858 paper for the ''Proceedings of the Linnean Society'', British zoologist Philip Sclater first identified six terrestrial zoogeographic realms of the world: Palaearctic, Aethiopian/ Afrotropic, Indian/ Indom ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Nearctic
The Nearctic realm is one of the eight biogeographic realms constituting the Earth's land surface. The Nearctic realm covers most of North America, including Greenland, Central Florida, and the highlands of Mexico. The parts of North America that are not in the Nearctic realm include most of coastal Mexico, southern Mexico, southern Florida, coastal central Florida, Central America, Bermuda and the Caribbean islands. Together with South America, these regions are part of the Neotropical realm. Major ecological regions The World Wildlife Fund (WWF) divides the Nearctic into four bioregions, defined as "geographic clusters of ecoregions that may span several habitat types, but have strong biogeographic affinities, particularly at taxonomic levels higher than the species level (genus, family)." Canadian Shield The Canadian Shield bioregion extends across the northern portion of the continent, from the Aleutian Islands to Newfoundland. It includes the Nearctic's arctic tun ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Neotropic
The Neotropical realm is one of the eight biogeographic realms constituting Earth's land surface. Physically, it includes the tropical terrestrial ecoregions of the Americas and the entire South American temperate zone. Definition In biogeography, the Neotropic or Neotropical realm is one of the eight terrestrial realms. This realm includes South America, Central America, the Caribbean Islands, and southern North America. In Mexico, the Yucatán Peninsula and southern lowlands, and most of the east and west coastlines, including the southern tip of the Baja California Peninsula are Neotropical. In the United States southern Florida and coastal Central Florida are considered Neotropical. The realm also includes temperate southern South America. In contrast, the Neotropical Floristic Kingdom excludes southernmost South America, which instead is placed in the Antarctic kingdom. The Neotropic is delimited by similarities in fauna or flora. Its fauna and flora are distinct f ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Xyleborini
Xyleborini are a tribe of ambrosia beetles (alternatively called subtribe Xyleborina of tribe Scolytini), highly specialized weevils of the subfamily Scolytinae. Much of the ambrosia beetle fauna in Eurasia and the Americas consists of Xyleborini species. Some Xyleborini are notorious invasive species. Most genera are small or even monotypic, and contain 1-8 dozen species. The type genus '' Xyleborus'' contains over 500 species, but it is an unnatural grouping of species which are not closely related. Key for the world genera of Xyleborini available through a North Carolina State University website. Genera Genera include: * ''Amasa'' Lea 1893 * '' Ambrosiodmus'' Hopkins, 1915 (sometimes included in ''Xyleborus'') * '' Ambrosiophilus'' Hulcr & Cognato 2009 * '' Ancipitis'' * '' Anisandrus'' Ferrari 1867 * '' Arixyleborus'' Hopkins 1915 * '' Beaverium'' Hulcr & Cognato 2009 * '' Cnestus'' Sampson 1911 * '' Coptoborus'' Hopkins, 1915 * '' Coptodryas'' Hopkins 1915 * '' Cryptoxylebo ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Paleotropical
The Paleotropical kingdom (Paleotropis) is a floristic kingdom composed of the tropical areas of Africa, Asia and Oceania (excluding Australia and New Zealand), as proposed by Ronald Good and Armen Takhtajan. Part of its flora is inherited from the ancient supercontinent of Gondwana or exchanged later (e.g. Piperaceae with pantropical distribution and but few warm temperate representatives). These Gondwanan lineages are related to those in the Neotropical kingdom, composed of the tropical areas of Central and South America. Flora from the Paleotropical kingdom influenced the tropical flora of the Australian Kingdom. The kingdom is subdivided into five floristic subkingdoms according to Takhtajan (or three, according to Good) and about 13 floristic regions. In this article the floristic subkingdoms and regions are given as delineated by Takhtajan. Origin A distinct community of vascular plants evolved millions of years ago, and are now found on several separate areas. Mill ... [...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] |
Clade
In biology, a clade (), also known as a Monophyly, monophyletic group or natural group, is a group of organisms that is composed of a common ancestor and all of its descendants. Clades are the fundamental unit of cladistics, a modern approach to taxonomy adopted by most biological fields. The common ancestor may be an individual, a population, or a species (extinct or Extant taxon, extant). Clades are nested, one in another, as each branch in turn splits into smaller branches. These splits reflect evolutionary history as populations diverged and evolved independently. Clades are termed ''monophyletic'' (Greek: "one clan") groups. Over the last few decades, the cladistic approach has revolutionized biological classification and revealed surprising evolutionary relationships among organisms. Increasingly, taxonomists try to avoid naming Taxon, taxa that are not clades; that is, taxa that are not Monophyly, monophyletic. Some of the relationships between organisms that the molecul ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
