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Clumping (biology)
Clumping is a behavior in an organism, usually sessile, in which individuals of a particular species group close to one another for beneficial purposes. Clumping can be caused by the abiotic environment surrounding an organism. Barnacles, for example, group together on rocks that are exposed for the least amount of time during the low tide. Usually, clumping in sessile animals starts when one organism binds to a hard substrate, such as rock, and other members of the same species attach themselves afterwards. Herbivorous snails are known to clump around where sufficient algae are present. The clumping of mussels (shown right) has been found to be influenced by competition with other species. The mussels attach themselves by byssal threads to potential competitors for space. Causes Predation avoidance Clumping and increased locomotion has been found to occur with organisms such as blue mussels ( ''Mytilus edulis'') due to risks from predators such as the European lobster (''Homaru ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Mussels On Rock
Mussel () is the common name used for members of several families of bivalve molluscs, from saltwater and freshwater habitats. These groups have in common a shell whose outline is elongated and asymmetrical compared with other edible clams, which are often more or less rounded or oval. The word "mussel" is frequently used to mean the bivalves of the marine family Mytilidae, most of which live on exposed shores in the intertidal zone, attached by means of their strong byssal threads ("beard") to a firm substrate. A few species (in the genus ''Bathymodiolus'') have colonised hydrothermal vents associated with deep ocean ridges. In most marine mussels the shell is longer than it is wide, being wedge-shaped or asymmetrical. The external colour of the shell is often dark blue, blackish, or brown, while the interior is silvery and somewhat nacreous. The common name "mussel" is also used for many freshwater bivalves, including the freshwater pearl mussels. Freshwater mussel species in ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Organism
In biology, an organism () is any living system that functions as an individual entity. All organisms are composed of cells (cell theory). Organisms are classified by taxonomy into groups such as multicellular animals, plants, and fungi; or unicellular microorganisms such as protists, bacteria, and archaea. All types of organisms are capable of reproduction, growth and development, maintenance, and some degree of response to stimuli. Beetles, squids, tetrapods, mushrooms, and vascular plants are examples of multicellular organisms that differentiate specialized tissues and organs during development. A unicellular organism may be either a prokaryote or a eukaryote. Prokaryotes are represented by two separate domains – bacteria and archaea. Eukaryotic organisms are characterized by the presence of a membrane-bound cell nucleus and contain additional membrane-bound compartments called organelles (such as mitochondria in animals and plants ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Sessility (motility)
Sessility is the biological property of an organism describing its lack of a means of self-locomotion. Sessile organisms for which natural ''motility'' is absent are normally immobile. This is distinct from the botanical concept of sessility, which refers to an organism or biological structure attached directly by its base without a stalk. Sessile organisms can move via external forces (such as water currents), but are usually permanently attached to something. Organisms such as corals lay down their own substrate from which they grow. Other sessile organisms grow from a solid such as a rock, dead tree trunk, or a man-made object such as a buoy or ship's hull. Mobility Sessile animals typically have a motile phase in their development. Sponges have a motile larval stage and become sessile at maturity. Conversely, many jellyfish develop as sessile polyps early in their life cycle. In the case of the cochineal, it is in the nymph stage (also called the crawler stage) that the ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Barnacles
A barnacle is a type of arthropod constituting the subclass Cirripedia in the subphylum Crustacea, and is hence related to crabs and lobsters. Barnacles are exclusively marine, and tend to live in shallow and tidal waters, typically in erosive settings. They are sessile (nonmobile) and most are suspension feeders, but those in infraclass Rhizocephala are highly specialized parasites on crustaceans. They have four nektonic (active swimming) larval stages. Around 1,000 barnacle species are currently known. The name is Latin, meaning "curl-footed". The study of barnacles is called cirripedology. Description Barnacles are encrusters, attaching themselves temporarily to a hard substrate or a symbiont such as a whale ( whale barnacles), a sea snake ('' Platylepas ophiophila''), or another crustacean, like a crab or a lobster (Rhizocephala). The most common among them, "acorn barnacles" ( Sessilia), are sessile where they grow their shells directly onto the substrate. Pedunculate ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Snails
A snail is, in loose terms, a shelled gastropod. The name is most often applied to land snails, terrestrial pulmonate gastropod molluscs. However, the common name ''snail'' is also used for most of the members of the molluscan class Gastropoda that have a coiled shell that is large enough for the animal to retract completely into. When the word "snail" is used in this most general sense, it includes not just land snails but also numerous species of sea snails and freshwater snails. Gastropods that naturally lack a shell, or have only an internal shell, are mostly called ''slugs'', and land snails that have only a very small shell (that they cannot retract into) are often called ''semi-slugs''. Snails have considerable human relevance, including as food items, as pests, and as vectors of disease, and their shells are used as decorative objects and are incorporated into jewelry. The snail has also had some cultural significance, tending to be associated with lethargy. The snai ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Mussels
Mussel () is the common name used for members of several families of bivalve mollusc Mollusca is the second-largest phylum of invertebrate animals after the Arthropoda, the members of which are known as molluscs or mollusks (). Around 85,000 extant species of molluscs are recognized. The number of fossil species is esti ...s, from saltwater and Freshwater bivalve, freshwater habitats. These groups have in common a shell whose outline is elongated and asymmetrical compared with other edible clams, which are often more or less rounded or oval. The word "mussel" is frequently used to mean the bivalves of the marine family Mytilidae, most of which live on exposed shores in the intertidal zone, attached by means of their strong Byssus, byssal threads ("beard") to a firm substrate. A few species (in the genus ''Bathymodiolus'') have colonised hydrothermal vents associated with deep ocean ridges. In most marine mussels the shell is longer than it is wide, being wedge-shaped ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Byssal Thread
A byssus () is a bundle of filaments secreted by many species of bivalve mollusc that function to attach the mollusc to a solid surface. Species from several families of clams have a byssus, including pen shells (Pinnidae), true mussels (Mytilidae), and Dreissenidae. Filaments Byssus filaments are created by certain kinds of marine and freshwater bivalve mollusks, which use the byssus to attach themselves to rocks, substrates, or seabeds. In edible mussels, the inedible byssus is commonly known as the "beard", and is removed before cooking. Many species of mussels secrete byssus threads to anchor themselves to surfaces, with families including the Arcidae, Mytilidae, Anomiidae, Pinnidae, Pectinidae, Dreissenidae, and Unionidae. Mechanics The byssus, or byssal complex, is composed of multiple extracellular collagenous threads that are placed radially by the mussel from a central stem. Each thread is composed of three regions: a corrugated proximal region close to the mussel b ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Blue Mussel
The blue mussel (''Mytilus edulis''), also known as the common mussel, is a medium-sized edible marine (ocean), marine bivalve mollusc in the family (biology), family Mytilidae, the mussels. Blue mussels are subject to commercial use and intensive aquaculture. A species with a large range, empty shells are commonly found on beaches around the world. Systematics and distribution The ''Mytilus edulis'' complex Systematically blue mussel consists of a group of (at least) three closely related taxa of mussels, known as the ''Mytilus edulis'' complex. Collectively they occupy both coasts of the North Atlantic (including the Mediterranean) and of the North Pacific in temperate to polar waters, as well as coasts of similar nature in the Southern Hemisphere. The distribution of the component taxa has been recently modified as a result of human activity. The taxa can hybridise with each other, if present at the same locality. *''Mytilus edulis'' sensu stricto: Native to the North Atla ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Homarus Gammarus
''Homarus gammarus'', known as the European lobster or common lobster, is a species of lobster, clawed lobster from the eastern Atlantic Ocean, Mediterranean Sea and parts of the Black Sea. It is closely related to the American lobster, ''H. americanus''. It may grow to a length of and a mass of , and bears a conspicuous pair of claws. In life the lobsters are blue, only becoming "lobster red" on cooking. Mating occurs in the summer, producing egg (biology), eggs which are carried by the females for up to a year before hatching into planktonic crustacean larvae, larvae. ''Homarus gammarus'' is a highly esteemed food, and is widely lobster fishing, caught using lobster trap, lobster pots, mostly around the British Isles. Description ''Homarus gammarus'' is a large crustacean, with a body length up to and weighing up to , although the lobsters caught in lobster trap, lobster pots are usually long and weigh . Like other crustaceans, lobsters have a hard exoskeleton which th ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Nucella Lamellosa
''Nucella lamellosa'', commonly known as the frilled dogwinkle or wrinkled purple whelk, is a species of sea snail, a marine gastropod mollusk in the family Muricidae, the murex snails or rock snails. This species occurs in the eastern Pacific Ocean, its range extending in the intertidal zone from the Aleutian Islands southward to central California. Description ''Nucella lamellosa'' is a large snail with a strong shell growing to a length of and width of . The shell has no more than seven whorls and has a horny operculum. The spire is well developed, with a short notch to accommodate the siphon. This snail is rather variable in colour, shape and surface texture. Some specimens are smooth, others rough and others have frilled lamellae (angular plates). Some of these features may be as a result of abrasion and wave action, and when present, the spiral sculpture takes the form of one or two ridges per whorl, the whorls being flattened near their joints making them appear to be an ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Quadrat
A quadrat is a frame, traditionally square, used in ecology, geography and biology to isolate a standard unit of area for study of the distribution of an item over a large area. Modern quadrats can for example be rectangular, circular, or irregular. The quadrat is suitable for sampling plants, slow-moving animals, and some aquatic organisms. A photo-quadrat is a photographic record of the area framed by a quadrat. It may use a physical frame to indicate the area, or may rely on fixed camera distance and lens field of view to automatically cover the specified area of substrate. Parallel laser pointers mounted on the camera can also be used as scale indicators. The photo is taken perpendicular to the surface, or as close as possible to perpendicular for uneven surfaces. History The systematic use of quadrats was developed by the pioneering plant ecologists R. Pound and F. E. Clements between 1898 and 1900. The method was then swiftly applied for many purposes in ecology, such a ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Agelenopsis Aperta
''Agelenopsis aperta'', also known as the desert grass spider or funnel-web spider, is a species of spider belonging to the family Agelenidae and the genus ''Agelenopsis''. It is found in dry and arid regions across the southern United States and into northwestern Mexico. Their body is about 13–18 mm long and they have relatively long legs in order to run after their prey. Desert grass spiders can withstand very low temperatures even though they do not Cold hardening, cold harden. It constructs the characteristic funnel-shaped webs in crevices where the funnel will fit, where they wait in the tube for prey which they can run after using their long legs. They often hunt for their prey at night. ''A. aperta'' is known for its territoriality and will fight intruders to protect their space. ''A. aperta'' are mainly monogamous, and the male performs an elaborate courtship ritual that involves swaying his abdomen and releasing pheromones. The male's pheromones induce a cataplec ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
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