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Shingle Urchin
''Colobocentrotus atratus'', the helmet urchin or shingle urchin, is a species of sea urchin in the family Echinometridae. In Hawaii it is known as "hāʻukeʻuke." It is found on wave-swept intertidal shores in the Indo-West Pacific, particularly on the shores of Hawaii. Description This urchin is a deep maroon colour and shaped like a domed limpet. It can grow to the size of a softball, but is usually much smaller. The upper surface is a mosaic of tiny polygonal plates formed from modified spines to form a smooth mosaic. This is fringed by a ring of large, flattened modified spines. On the underside there is another ring of smaller flattened spines and a large number of tube feet. Biology This urchin is usually found on substrates fully exposed to waves and their associated abrasive effect, often in groups. It feeds on periwinkles, other urchins and coralline algae Coralline algae are red algae in the order Corallinales. They are characterized by a thallus that is hard b ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Animal
Animals are multicellular, eukaryotic organisms in the Kingdom (biology), biological kingdom Animalia. With few exceptions, animals Heterotroph, consume organic material, Cellular respiration#Aerobic respiration, breathe oxygen, are Motility, able to move, can Sexual reproduction, reproduce sexually, and go through an ontogenetic stage in which their body consists of a hollow sphere of Cell (biology), cells, the blastula, during Embryogenesis, embryonic development. Over 1.5 million Extant taxon, living animal species have been Species description, described—of which around 1 million are Insecta, insects—but it has been estimated there are over 7 million animal species in total. Animals range in length from to . They have Ecology, complex interactions with each other and their environments, forming intricate food webs. The scientific study of animals is known as zoology. Most living animal species are in Bilateria, a clade whose members have a Symmetry in biology#Bilate ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Hawaii
Hawaii ( ; haw, Hawaii or ) is a state in the Western United States, located in the Pacific Ocean about from the U.S. mainland. It is the only U.S. state outside North America, the only state that is an archipelago, and the only state geographically located within the tropics. Hawaii comprises nearly the entire Hawaiian archipelago, 137 volcanic islands spanning that are physiographically and ethnologically part of the Polynesian subregion of Oceania. The state's ocean coastline is consequently the fourth-longest in the U.S., at about . The eight main islands, from northwest to southeast, are Niihau, Kauai, Oahu, Molokai, Lānai, Kahoolawe, Maui, and Hawaii—the last of these, after which the state is named, is often called the "Big Island" or "Hawaii Island" to avoid confusion with the state or archipelago. The uninhabited Northwestern Hawaiian Islands make up most of the Papahānaumokuākea Marine National Monument, the United States' largest protected ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Echinometra
''Echinometra'' is a genus of sea urchins in the family Echinometridae. Species The following species In biology, a species is the basic unit of classification and a taxonomic rank of an organism, as well as a unit of biodiversity. A species is often defined as the largest group of organisms in which any two individuals of the appropriate s ... are listed in the World Echinoidea Database: References {{Taxonbar, from=Q3046974 Echinometridae ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Coralline Algae
Coralline algae are red algae in the order Corallinales. They are characterized by a thallus that is hard because of calcareous deposits contained within the cell walls. The colors of these algae are most typically pink, or some other shade of red, but some species can be purple, yellow, blue, white, or gray-green. Coralline algae play an important role in the ecology of coral reefs. Sea urchins, parrot fish, and limpets and chitons (both mollusks) feed on coralline algae. In the temperate Mediterranean Sea, coralline algae are the main builders of a typical algal reef, the ''Coralligène'' ("coralligenous"). Many are typically encrusting and rock-like, found in marine waters all over the world. Only one species lives in freshwater. Unattached specimens ( maerl, rhodoliths) may form relatively smooth compact balls to warty or fruticose thalli. A close look at almost any intertidal rocky shore or coral reef will reveal an abundance of pink to pinkish-grey patches, distributed throu ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Common Periwinkle
The common periwinkle or winkle (''Littorina littorea'') is a species of small edible whelk or sea snail, a marine gastropod mollusc that has gills and an operculum, and is classified within the family Littorinidae, the periwinkles.Reid, David G.; Gofas, S. (2011). Littorina littorea (Linnaeus, 1758). Accessed through: World Register of Marine Species at http://www.marinespecies.org/aphia.php?p=taxdetails&id=140262 on 2011-05-16 This is a robust intertidal species with a dark and sometimes banded shell. It is native to the rocky shores of the northeastern, and introduced to the northwestern, Atlantic Ocean. There is another snail known as the small periwinkle or ''Melarhaphe neritoides'' that looks similar, but is smaller. Description The shell is broadly ovate, thick, and sharply pointed except when eroded. The shell contains six to seven whorls with some fine threads and wrinkles. The color varies from grayish to gray-brown, often with dark spiral bands. The base of th ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Abrasion (mechanical)
Abrasion is the process of scuffing, scratching, wearing down, marring, or rubbing away. It can be intentionally imposed in a controlled process using an abrasive. Abrasion can be an undesirable effect of exposure to normal use or exposure to the elements. In stone shaping Ancient artists, working in stone, used abrasion to create sculptures. The artist selected dense stones like carbonite and emery and rubbed them consistently against comparatively softer stones like limestone and granite. The artist used different sizes and shapes of abrasives, or turned them in various ways as they rubbed, to create effects on the softer stone's surface. Water was continuously poured over the surface to carry away particles. Abrasive technique in stone shaping was a long, tedious process that, with patience, resulted in eternal works of art in stone. Models The Archard equation is a simple model used to describe sliding wear and is based on the theory of asperity contact. Q = \frac H whe ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Substrate (marine Biology)
Stream substrate (sediment) is the material that rests at the bottom of a stream. There are several classification guides. One is: *Mud – silt and clay. *Sand – Particles between 0.06 and 2 mm in diameter. * Granule – Between 2 and 4 mm in diameter. *Pebble – Between 4 – 64 mm in diameter. *Cobble – between 6.4 and 25.6 cm in diameter *Boulder – more than 25.6 cm in diameter. Stream substrate can affect the life found within the stream habitat. Muddy streams generally have more sediment in the water, reducing clarity. Clarity is one guide to stream health. Marine substrate can be classified geologically as well. See Green et al., 1999 for a reference. Mollusks and clams that live in areas with substrate, and need them to survive, use their silky byssal threads to cling to it. See Cteniodes Ales for reference. See also * Grain size * Substrate (biology) In biology, a substrate is the surface on which an organism (such as a plant, fungus, ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Tube Feet
Tube feet (technically podia) are small active tubular projections on the oral face of an echinoderm, whether the arms of a starfish, or the undersides of sea urchins, sand dollars and sea cucumbers; they are more discreet though present on brittle stars, and have only a feeding function in feather stars. They are part of the water vascular system. Structure and function Tube feet function in locomotion, feeding, and respiration. The tube feet in a starfish are arranged in grooves along the arms. They operate through hydraulic pressure. They are used to pass food to the oral mouth at the center, and can attach to surfaces. A starfish that is inverted turns one arm over and attaches it to a solid surface, and levers itself the right way up. Tube feet allow these different types of animals to stick to the ocean floor and move slowly. Each tube foot consists of two parts: the ampulla and the podium. The ampulla is a water-filled sac contained in the body of the animal that contain ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Limpet
Limpets are a group of aquatic snails that exhibit a conical shell shape (patelliform) and a strong, muscular foot. Limpets are members of the class Gastropoda, but are polyphyletic, meaning the various groups called "limpets" descended independently from different ancestral gastropods. This general category of conical shell is known as "patelliform" (dish-shaped). All members of the large and ancient marine clade Patellogastropoda are limpets. Within that clade, the members of the Patellidae family in particular are often referred to as "true limpets". Other groups, not in the same family, are also called limpets of one type or another, due to the similarity of their shells' shape. Examples include the Fissurellidae ("keyhole limpet") family, which is part of the Vetigastropoda clade (many other members of the Vetigastropoda do not have the morphology of limpets) and the Siphonariidae ("false limpets"), which use a siphon to pump water over their gills. Behaviour and ecolo ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Indo-West Pacific
The Indo-Pacific is a vast biogeographic region of Earth. In a narrow sense, sometimes known as the Indo-West Pacific or Indo-Pacific Asia, it comprises the tropical waters of the Indian Ocean, the western and central Pacific Ocean, and the seas connecting the two in the general area of Indonesia. It does not include the temperate and polar regions of the Indian and Pacific oceans, nor the Tropical Eastern Pacific, along the Pacific coast of the Americas, which is also a distinct marine realm. The term is especially useful in marine biology, ichthyology, and similar fields, since many marine habitats are continuously connected from Madagascar to Japan and Oceania, and a number of species occur over that range, but are not found in the Atlantic Ocean. The region has an exceptionally high species richness, with the world's highest species richness being found in at its heart in the Coral Triangle, and a remarkable gradient of decreasing species richness radiating outward in a ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Echinodermata
An echinoderm () is any member of the phylum Echinodermata (). The adults are recognisable by their (usually five-point) radial symmetry, and include starfish, brittle stars, sea urchins, sand dollars, and sea cucumbers, as well as the sea lilies or "stone lilies". Adult echinoderms are found on the sea bed at every ocean depth, from the intertidal zone to the abyssal zone. The phylum contains about 7,000 living species, making it the second-largest grouping of deuterostomes, after the chordates. Echinoderms are the largest entirely marine phylum. The first definitive echinoderms appeared near the start of the Cambrian. The echinoderms are important both ecologically and geologically. Ecologically, there are few other groupings so abundant in the biotic desert of the deep sea, as well as shallower oceans. Most echinoderms are able to reproduce asexually and regenerate tissue, organs, and limbs; in some cases, they can undergo complete regeneration from a single limb. Geolo ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Sea Urchin
Sea urchins () are spiny, globular echinoderms in the class Echinoidea. About 950 species of sea urchin live on the seabed of every ocean and inhabit every depth zone from the intertidal seashore down to . The spherical, hard shells (tests) of sea urchins are round and spiny, ranging in diameter from . Sea urchins move slowly, crawling with tube feet, and also propel themselves with their spines. Although algae are the primary diet, sea urchins also eat slow-moving (sessile) animals. Predators that eat sea urchins include a wide variety of fish, starfish, crabs, marine mammals. Sea urchins are also used as food especially in Japan. Adult sea urchins have fivefold symmetry, but their pluteus larvae feature bilateral (mirror) symmetry, indicating that the sea urchin belongs to the Bilateria group of animal phyla, which also comprises the chordates and the arthropods, the annelids and the molluscs, and are found in every ocean and in every climate, from the tropics to the pol ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
