The intertidal zone known as the foreshore and seashore and sometimes referred to as the littoral zone, is the area, above water at low tide and underwater at high tide. This area can include many different types of habitats, with many types of animals, such as starfish, sea urchins, numerous species of coral; the well-known area includes steep rocky cliffs, sandy beaches, or wetlands. The area can be a narrow strip, as in Pacific islands that have only a narrow tidal range, or can include many meters of shoreline where shallow beach slopes interact with high tidal excursion. Peritidal zone is similar but a somewhat wider zone, extending from above the highest tide level to below that of the lowest tide level. Organisms in the intertidal zone are adapted to an environment of harsh extremes; the intertidal zone is home to many several species from different taxa including Porifera, Coelenterates, crustaceans, etc. Water is available with the tides but varies from fresh with rain to saline and dry salt with drying between tidal inundations.
Wave splash can dislodge residents from the littoral zone. With the intertidal zone's high exposure to the sun, the temperature range can be anything from hot with full sun to near freezing in colder climates; some microclimates in the littoral zone are ameliorated by local features and larger plants such as mangroves. Adaptation in the littoral zone allows the use of nutrients supplied in high volume on a regular basis from the sea, moved to the zone by tides. Edges of habitats, in this case land and sea, are themselves significant ecologies, the littoral zone is a prime example. A typical rocky shore can be divided into a spray zone or splash zone, above the spring high-tide line and is covered by water only during storms, an intertidal zone, which lies between the high and low tidal extremes. Along most shores, the intertidal zone can be separated into the following subzones: high tide zone, middle tide zone, low tide zone; the intertidal zone is one of a number of marine biomes or habitats, including estuaries, neritic and deep zones.
Marine biologists divide the intertidal region into three zones, based on the overall average exposure of the zone. The low intertidal zone, which borders on the shallow subtidal zone, is only exposed to air at the lowest of low tides and is marine in character; the mid intertidal zone is exposed and submerged by average tides. The high intertidal zone is only covered by the highest of the high tides, spends much of its time as terrestrial habitat; the high intertidal zone borders on the splash zone. On shores exposed to heavy wave action, the intertidal zone will be influenced by waves, as the spray from breaking waves will extend the intertidal zone. Depending on the substratum and topography of the shore, additional features may be noticed. On rocky shores, tide pools form in depressions. Under certain conditions, such as those at Morecambe Bay, quicksand may form; this subregion is submerged - it is only exposed at the point of low tide and for a longer period of time during low tides. This area is teeming with life.
There is a great biodiversity. Organisms in this zone are not well adapted to periods of dryness and temperature extremes; some of the organisms in this area are abalone, sea anemones, brown seaweed, crabs, green algae, isopods, mussels, sculpin, sea cucumber, sea lettuce, sea palms, sea urchins, snails, surf grass, tube worms, whelks. Creatures in this area can grow to larger sizes because there is more available energy in the localized ecosystem. Marine vegetation can grow to much greater sizes than in the other three intertidal subregions due to the better water coverage; the water is shallow enough to allow plenty of light to reach the vegetation to allow substantial photosynthetic activity, the salinity is at normal levels. This area is protected from large predators such as fish because of the wave action and the shallow water; the intertidal region is an important model system for the study of ecology on wave-swept rocky shores. The region contains a high diversity of species, the zonation created by the tides causes species ranges to be compressed into narrow bands.
This makes it simple to study species across their entire cross-shore range, something that can be difficult in, for instance, terrestrial habitats that can stretch thousands of kilometres. Communities on wave-swept shores have high turnover due to disturbance, so it is possible to watch ecological succession over years rather than decades; the burrowing invertebrates that make up large portions of sandy beach ecosystems are known to travel great distances in cross-shore directions as beaches change on the order of days, semilunar cycles, seasons, or years. The distribution of some species has been found to correlate with geomorphic datums such as the high tide strand and the water table outcrop. Since the foreshore is alternately covered by the sea and exposed to the air, organisms living in this environment must have adaptions for both wet and dry conditions. Hazards include being smashed or carried away by rough waves, exposure to dangerously high temperatures, desiccation. Typical inhabit
Vertebrates comprise all species of animals within the subphylum Vertebrata. Vertebrates represent the overwhelming majority of the phylum Chordata, with about 69,276 species described. Vertebrates include the jawless fishes and jawed vertebrates, which include the cartilaginous fishes and the bony fishes; the bony fishes in turn, cladistically speaking include the tetrapods, which include amphibians, reptiles and mammals. Extant vertebrates range in size from the frog species Paedophryne amauensis, at as little as 7.7 mm, to the blue whale, at up to 33 m. Vertebrates make up less than five percent of all described animal species; the vertebrates traditionally include the hagfish, which do not have proper vertebrae due to their loss in evolution, though their closest living relatives, the lampreys, do. Hagfish do, possess a cranium. For this reason, the vertebrate subphylum is sometimes referred to as "Craniata" when discussing morphology. Molecular analysis since 1992 has suggested that hagfish are most related to lampreys, so are vertebrates in a monophyletic sense.
Others consider them a sister group of vertebrates in the common taxon of craniata. The word vertebrate derives from the Latin word vertebratus. Vertebrate is derived from the word vertebra, which refers to any of the bones or segments of the spinal column. All vertebrates are built along the basic chordate body plan: a stiff rod running through the length of the animal, with a hollow tube of nervous tissue above it and the gastrointestinal tract below. In all vertebrates, the mouth is found at, or right below, the anterior end of the animal, while the anus opens to the exterior before the end of the body; the remaining part of the body continuing after the anus forms a tail with vertebrae and spinal cord, but no gut. The defining characteristic of a vertebrate is the vertebral column, in which the notochord found in all chordates has been replaced by a segmented series of stiffer elements separated by mobile joints. However, a few vertebrates have secondarily lost this anatomy, retaining the notochord into adulthood, such as the sturgeon and coelacanth.
Jawed vertebrates are typified by paired appendages, but this trait is not required in order for an animal to be a vertebrate. All basal vertebrates breathe with gills; the gills are carried right behind the head, bordering the posterior margins of a series of openings from the pharynx to the exterior. Each gill is supported by a cartilagenous or bony gill arch; the bony fish have three pairs of arches, cartilaginous fish have five to seven pairs, while the primitive jawless fish have seven. The vertebrate ancestor no doubt had more arches than this, as some of their chordate relatives have more than 50 pairs of gills. In amphibians and some primitive bony fishes, the larvae bear external gills, branching off from the gill arches; these are reduced in adulthood, their function taken over by the gills proper in fishes and by lungs in most amphibians. Some amphibians retain the external larval gills in adulthood, the complex internal gill system as seen in fish being irrevocably lost early in the evolution of tetrapods.
While the more derived vertebrates lack gills, the gill arches form during fetal development, form the basis of essential structures such as jaws, the thyroid gland, the larynx, the columella and, in mammals, the malleus and incus. The central nervous system of vertebrates is based on a hollow nerve cord running along the length of the animal. Of particular importance and unique to vertebrates is the presence of neural crest cells; these are progenitors of stem cells, critical to coordinating the functions of cellular components. Neural crest cells migrate through the body from the nerve cord during development, initiate the formation of neural ganglia and structures such as the jaws and skull; the vertebrates are the only chordate group to exhibit cephalisation, the concentration of brain functions in the head. A slight swelling of the anterior end of the nerve cord is found in the lancelet, a chordate, though it lacks the eyes and other complex sense organs comparable to those of vertebrates.
Other chordates do not show any trends towards cephalisation. A peripheral nervous system branches out from the nerve cord to innervate the various systems; the front end of the nerve tube is expanded by a thickening of the walls and expansion of the central canal of spinal cord into three primary brain vesicles: The prosencephalon and rhombencephalon, further differentiated in the various vertebrate groups. Two laterally placed eyes form around outgrowths from the midbrain, except in hagfish, though this may be a secondary loss; the forebrain is well developed and subdivided in most tetrapods, while the midbrain dominates in many fish and some salamanders. Vesicles of the forebrain are paired, giving rise to hemispheres like the cerebral hemispheres in mammals; the resulting anatomy of the central nervous system, with a single hollow nerve cord topped by a series of vesicles, is unique to vertebrates. All invertebrates with well-developed brains, such as insects and squids, have a ventral rather than dorsal system of ganglions, with a split brain stem running on each side of the mouth or gut.
Vertebrates originated about 525 million years ago during the Cambrian explosion, which saw
Gulls or seagulls are seabirds of the family Laridae in the suborder Lari. They are most related to the terns and only distantly related to auks and more distantly to the waders; until the 21st century, most gulls were placed in the genus Larus, but this arrangement is now considered polyphyletic, leading to the resurrection of several genera. An older name for gulls is mews, cognate with German Möwe, Danish måge, Dutch meeuw, French mouette. Gulls are medium to large birds grey or white with black markings on the head or wings, they have harsh wailing or squawking calls. Most gulls are ground-nesting carnivores which take live food or scavenge opportunistically the Larus species. Live food includes crabs and small fish. Gulls have unhinging jaws. Gulls are coastal or inland species venturing far out to sea, except for the kittiwakes; the large species take up to four years to attain full adult plumage, but two years is typical for small gulls. Large white-headed gulls are long-lived birds, with a maximum age of 49 years recorded for the herring gull.
Gulls nest in large, densely packed, noisy colonies. They lay three speckled eggs in nests composed of vegetation; the young are precocial, mobile upon hatching. Gulls are resourceful and intelligent, the larger species in particular, demonstrating complex methods of communication and a developed social structure. For example, many gull colonies display mobbing behavior and harassing predators and other intruders. Certain species have exhibited tool-use behavior, such as the herring gull, using pieces of bread as bait with which to catch goldfish, for example. Many species of gulls have learned to coexist with humans and have thrived in human habitats. Others rely on kleptoparasitism to get their food. Gulls have been observed preying on live whales, landing on the whale as it surfaces to peck out pieces of flesh. Gulls range in size from the little gull, at 120 g and 29 cm, to the great black-backed gull, at 1.75 kg and 76 cm. They are uniform in shape, with heavy bodies, long wings, moderately long necks.
The tails of all but three species are rounded. Gulls have moderately long legs when compared to the similar terns, with webbed feet; the bill is heavy and hooked, with the larger species having stouter bills than the smaller species. The bill colour is yellow with a red spot for the larger white-headed species and red, dark red or black in the smaller species; the gulls are generalist feeders. Indeed, they are the least specialised of all the seabirds, their morphology allows for equal adeptness in swimming and walking, they are more adept walking on land than most other seabirds, the smaller gulls tend to be more manoeuvrable while walking. The walking gait of gulls includes a slight side to side motion, something that can be exaggerated in breeding displays. In the air, they are able to hover and they are able to take off with little space; the general pattern of plumage in adult gulls is a white body with a darker mantle. A few species vary in this, the ivory gull is white, some like the lava gull and Heermann's gull have or grey bodies.
The wingtips of most species are black, which improves their resistance to wear and tear with a diagnostic pattern of white markings. The head of a gull may be covered by a dark hood or be white; the plumage of the head varies by breeding season. The gulls have a worldwide cosmopolitan distribution, they breed on every continent, including the margins of Antarctica, are found in the high Arctic, as well. They are less common on tropical islands, although a few species do live on islands such as the Galapagos and New Caledonia. Many species breed in coastal colonies, with a preference for islands, one species, the grey gull, breeds in the interior of dry deserts far from water. Considerable variety exists in the family and species may breed and feed in marine, freshwater, or terrestrial habitats. Most gull species are migratory, with birds moving to warmer habitats during the winter, but the extent to which they migrate varies by species; some migrate long distances, like Franklin's gull, which migrates from Canada to wintering grounds in the south of South America.
Other species move much shorter distances and may disperse along the coasts near their breeding sites. Charadriiform birds drink salt water, as well as fresh water, as they possess exocrine glands located in supraorbital grooves of the skull by which salt can be excreted through the nostrils to assist the kidneys in maintaining electrolyte balance. Gulls are adaptable feeders that opportunistically take a wide range of prey; the food taken by gulls includes fish and marine and freshwater invertebrates, both alive and dead, terrestrial arthropods and invertebrates such as insects and earthworms, eggs, offal, amphibians, plant items such as seeds and fruit, human refuse and other birds. No gull species is a single-prey specialist, no gull species forages using only a single method; the type of food depe
Tides are the rise and fall of sea levels caused by the combined effects of the gravitational forces exerted by the Moon and the Sun, the rotation of the Earth. Tide tables can be used for any given locale to find the predicted times and amplitude; the predictions are influenced by many factors including the alignment of the Sun and Moon, the phase and amplitude of the tide, the amphidromic systems of the oceans, the shape of the coastline and near-shore bathymetry. They are however only predictions, the actual time and height of the tide is affected by wind and atmospheric pressure. Many shorelines experience low tides each day. Other locations have a diurnal tide -- one low tide each day. A "mixed tide" – two uneven magnitude tides a day – is a third regular category. Tides vary on timescales ranging from hours to years due to a number of factors, which determine the lunitidal interval. To make accurate records, tide gauges at fixed stations measure water level over time. Gauges ignore; these data are compared to the reference level called mean sea level.
While tides are the largest source of short-term sea-level fluctuations, sea levels are subject to forces such as wind and barometric pressure changes, resulting in storm surges in shallow seas and near coasts. Tidal phenomena are not limited to the oceans, but can occur in other systems whenever a gravitational field that varies in time and space is present. For example, the shape of the solid part of the Earth is affected by Earth tide, though this is not as seen as the water tidal movements. Tide changes proceed via the following stages: Sea level rises over several hours, covering the intertidal zone; the water rises to its highest level. Sea level falls over several hours; the water stops reaching low tide. Oscillating currents produced by tides are known as tidal streams; the moment that the tidal current ceases is called slack tide. The tide reverses direction and is said to be turning. Slack water occurs near high water and low water, but there are locations where the moments of slack tide differ from those of high and low water.
Tides are semi-diurnal, or diurnal. The two high waters on a given day are not the same height; the two low waters each day are the higher low water and the lower low water. The daily inequality is not consistent and is small when the Moon is over the Equator. From the highest level to the lowest: Highest astronomical tide – The highest tide which can be predicted to occur. Note that meteorological conditions may add extra height to the HAT. Mean high water springs – The average of the two high tides on the days of spring tides. Mean high water neaps – The average of the two high tides on the days of neap tides. Mean sea level – This is the average sea level; the MSL is constant for any location over a long period. Mean low water neaps – The average of the two low tides on the days of neap tides. Mean low water springs – The average of the two low tides on the days of spring tides. Lowest astronomical tide and Chart Datum – The lowest tide which can be predicted to occur. Modern charts use this as the chart datum.
Note that under certain meteorological conditions the water may fall lower than this meaning that there is less water than shown on charts. Tidal constituents are the net result of multiple influences impacting tidal changes over certain periods of time. Primary constituents include the Earth's rotation, the position of the Moon and Sun relative to the Earth, the Moon's altitude above the Earth's Equator, bathymetry. Variations with periods of less than half a day are called harmonic constituents. Conversely, cycles of days, months, or years are referred to as long period constituents. Tidal forces affect the entire earth. In contrast, the atmosphere is much more fluid and compressible so its surface moves by kilometers, in the sense of the contour level of a particular low pressure in the outer atmosphere. In most locations, the largest constituent is the "principal lunar semi-diurnal" known as the M2 tidal constituent, its period is about 12 hours and 25.2 minutes half a tidal lunar day, the average time separating one lunar zenith from the next, thus is the time required for the Earth to rotate once relative to the Moon.
Simple tide clocks track this constituent. The lunar day is longer than the Earth day because the Moon orbits in the same direction the Earth spins; this is analogous to the minute hand on a watch crossing the hour hand at 12:00 and again at about 1:05½. The Moon orbits the Earth in the same direction as the Earth rotates on its axis, so it takes more than a day—about 24 hours and 50 minutes—for the Moon to return to the same location in the sky. During this time, it has passed overhead once and underfoot once, so in many places the period of strongest tidal forcing is the above-mentioned, about 12 hours and 25 minutes; the moment of highest tide is not when the Moon is nearest to zenith or nadir, but the period of the forcing still determines the time between high tides. Because the gravitational field created by the Moon weakens
Clam is a common name for several kinds of bivalve molluscs. The word is applied only to those that are edible and live as infauna, spending most of their lives buried in the sand of the ocean floor. Clams have two shells of equal size connected by two adductor muscles and have a powerful burrowing foot. Clams in the culinary sense do not live near the bottom. In culinary usage, clams are eaten marine bivalves, as in clam digging and the resulting soup, clam chowder. Many edible clams such as palourde clams are triangular; some clams have life cycles of only one year. All clams have two calcareous shells or valves joined near a hinge with a flexible ligament, all are filter feeders. A clam's shell consists of two valves, which are connected by a hinge joint and a ligament that can be external or internal; the ligament provides tension to bring the valves apart, while one or two adductor muscles can contract to close the valves. Clams have kidneys, a heart, a mouth, a stomach, a nervous system and an anus.
Many have a siphon. In culinary use, within the eastern coast of the United States and large swathes of the Maritimes of Canada, the term "clam" most refers to the hard clam Mercenaria mercenaria, it may refer to a few other common edible species, such as the soft-shell clam, Mya arenaria and the ocean quahog, Arctica islandica. Another species commercially exploited on the Atlantic Coast of the United States is the surf clam Spisula solidissima. Scallops are used for food nationwide, but not cockles: they are more difficult to get than in Europe because of their habit of being farther out in the tide than European species on the West Coast, on the East Coast they are found in salt marshes and mudflats where mosquitoes are abundant. Up and down the coast of the Eastern U. S. the bamboo clam, ensis directus, is prized by Americans for making clam strips although because of its nature of burrowing into the sand close to the beach, it cannot be harvested by mechanical means without damaging the beaches.
The bamboo clam is notorious for having a sharp edge of its shell, when harvested by hand must be handled with great care. On the U. S. West Coast, there are several species that have been consumed for thousands of years, evidenced by middens full of clamshells near the shore and their consumption by nations including the Chumash of California, the Nisqually of Washington State and the Tsawwassen of British Columbia; the butter clam, Saxidomus gigantea, the Pacific razor clam, Siliqua patula, gaper clams Tresus capax, the geoduck clam, Panopea generosa and the Pismo clam, Tivela stultorum are all eaten as delicacies. Clams can be eaten raw, boiled, baked or fried, they can be made into clam chowder, clams casino, Clam cakes, stuffies, or they can be cooked using hot rocks and seaweed in a New England clam bake. On the West Coast, they are an ingredient in making cioppino and local variants of ceviche In Japan, clams are an ingredient of mixed seafood dishes, they can be made into hot pot, miso soup or Tsukudani.
The more used varieties of clams in Japanese cooking are the Shijimi, the Asari and the Hamaguri. In Italy, clams are an ingredient of mixed seafood dishes or are eaten together with pasta; the more used varieties of clams in Italian cooking are the Vongola, the Cozza and the Tellina. Though Dattero di mare was once eaten, overfishing drove it to the verge of extinction and the Italian government has declared it an endangered species since 1998 and its harvest and sale are forbidden. Clams are eaten more in the coastal regions of India in the Konkan, Kerala and coastal regions of Karnataka regions. In Kerala clams are used to make fried with coconut. In Malabar region it is known as "elambakka" and in middle kerala it is known as "kakka". Clam curry made with coconut is a dish from Malabar in the Thalassery region. On the south western coast of India known as the Konkan region of Maharashtra, clams are used in curries and side dishes, like Tisaryachi Ekshipi, clams with one shell on. Beary Muslim households in the Mangalore region prepare a main dish with clams called Kowldo Pinde.
In Udupi and Mangalore regions it is famously called as "marvai" in local tulu language. It is used to prepare many delicious dishes like marvai sukka, marvai gassi, marvai pundi. Local fishermen sell them in rural markets. In Judaism, clams are considered non-kosher; some species of clams Mercenaria mercenaria, were in the past used by the Algonquians of Eastern North America to manufacture wampum, a type of sacred jewelry. Edible: Grooved carpet shell: Ruditapes decussatus Hard clam or Northern Quahog: Mercenaria mercenaria Manila clam: Venerupis philippinarum Soft clam: Mya arenaria Atlantic surf clam: Spisula solidissima Ocean quahog: Arctica islandica Pacific razor clam: Siliqua patula Pismo clam: Tivela stultorum Geoduck: Panopea abrupta or Panope generosa Atlantic jackknife clam: Ensis directus Lyrate Asiat
Desiccation is the state of extreme dryness, or the process of extreme drying. A desiccant is a hygroscopic substance that induces or sustains such a state in its local vicinity in a moderately sealed container. Desiccation is employed in the oil and gas industry; these materials are obtained in a hydrated state, but the water content leads to corrosion or is incompatible with downstream processing. Removal of water is achieved by cryogenic condensation, absorption into glycols, absorption onto desiccants such as silica gel. A desiccator is a heavy glass or plastic container, now somewhat antiquated, used in practical chemistry for drying or keeping small amounts of materials dry; the material is placed on a shelf, a drying agent or desiccant, such as dry silica gel or anhydrous sodium hydroxide, is placed below the shelf. Some sort of humidity indicator is included in the desiccator to show, by color changes, the level of humidity; these indicators are in the form of indicator plugs or indicator cards.
The active chemical is cobalt chloride. Anhydrous cobalt chloride is blue; when it bonds with two water molecules, it turns purple. Further hydration results in the pink hexaaquacobalt chloride complex 2+. In biology and ecology, desiccation refers to the drying out of a living organism, such as when aquatic animals are taken out of water, slugs are exposed to salt, or when plants are exposed to sunlight or drought. Ecologists study and assess various organisms' susceptibility to desiccation. For example, in one study the investigators found that Caenorhabditis elegans dauer is a true anhydrobiote that can withstand extreme desiccation and that the basis of this ability is founded in the metabolism of trehalose. Several bacterial species have been shown to accumulate DNA damages upon desiccation. Deinococcus radiodurans is resistant to ionizing radiation; the functions necessary to survive ionizing radiation are necessary to survive prolonged desiccation. Radiation resistance is considered to be an incidental consequence of the organism's evolutionary adaptation to dehydration, a common physiological stress in nature.
The chromosomal DNA from desiccated D. radiodurans revealed increased DNA double-strand breaks. DNA double-strand breaks are repaired principally by a RecA-dependent recombination process that requires the presence of two genome copies. By this process D. radiodurans can survive thousands of double-strand breaks per cell. Mycobacterium smegmatis mutant strains that are deficient in the ability to repair double-strand breaks by the non-homologous enjoining pathway are more sensitive to prolonged desiccation during stationary phase than wild-type strains. NHEJ appears to be the preferred pathway for repairing double-strand breaks caused by desiccation during stationary phase. NHEJ can repair double-strand breaks when only one chromosome is present in a cell. Upon exposure to extreme dryness, Bacillus subtilis endospores acquire DNA-double strand breaks and DNA-protein crosslinks. In broadcast engineering, a desiccator may be used to pressurize the feedline of a high-power transmitter; because it carries a large amount of energy from the transmitter to the antenna, the feedline must have low dielectric losses.
Because it must be lightweight so as not to overload the radio tower, air is used as the dielectric. Since moisture can condense in these lines, desiccated air or nitrogen gas is pumped in; this pressure keeps water or other dampness from coming in the line at any point along its length. Deposition List of desiccants Hygroscopy Mummy
Predation is a biological interaction where one organism, the predator and eats another organism, its prey. It is one of a family of common feeding behaviours that includes parasitism and micropredation and parasitoidism, it is distinct from scavenging on dead prey, though many predators scavenge. Predators may search for prey or sit and wait for it; when prey is detected, the predator assesses. This may involve pursuit predation, sometimes after stalking the prey. If the attack is successful, the predator kills the prey, removes any inedible parts like the shell or spines, eats it. Predators are adapted and highly specialized for hunting, with acute senses such as vision, hearing, or smell. Many predatory animals, both vertebrate and invertebrate, have sharp claws or jaws to grip and cut up their prey. Other adaptations include aggressive mimicry that improve hunting efficiency. Predation has a powerful selective effect on prey, the prey develop antipredator adaptations such as warning coloration, alarm calls and other signals, mimicry of well-defended species, defensive spines and chemicals.
Sometimes predator and prey find themselves in an evolutionary arms race, a cycle of adaptations and counter-adaptations. Predation has been a major driver of evolution since at least the Cambrian period. At the most basic level, predators eat other organisms. However, the concept of predation is broad, defined differently in different contexts, includes a wide variety of feeding methods. A parasitoid, such as an ichneumon wasp, lays its eggs on its host. Zoologists call this a form of parasitism, though conventionally parasites are thought not to kill their hosts. A predator can be defined to differ from a parasitoid in two ways: it kills its prey immediately. There are other borderline cases. Micropredators are small animals that, like predators, feed on other organisms. However, since they do not kill their hosts, they are now thought of as parasites. Animals that graze on phytoplankton or mats of microbes are predators, as they consume and kill their food organisms. However, when animals eat seeds or eggs, they are consuming entire living organisms, which by definition makes them predators, albeit unconventional ones: for instance, a mouse that eats grass seeds has no adaptations for tracking and subduing prey and its teeth are not adapted to slicing through flesh.
Scavengers, organisms that only eat organisms found dead, are not predators, but many predators such as the jackal and the hyena scavenge when the opportunity arises. Among invertebrates, social wasps are both scavengers of other insects. While examples of predators among mammals and birds are well known, predators can be found in a broad range of taxa, they are common among insects, including mantids, dragonflies and scorpionflies. In some species such as the alderfly, only the larvae are predatory. Spiders are predatory, as well as other terrestrial invertebrates such as scorpions. In marine environments, most cnidarians, ctenophora and flatworms are predatory. Among crustaceans, crabs and barnacles are predators, in turn crustaceans are preyed on by nearly all cephalopods. Seed predation is restricted to mammals and insects and is found in all terrestrial ecosystems. Egg predation includes both specialist egg predators such as some colubrid snakes and generalists such as foxes and badgers that opportunistically take eggs when they find them.
Some plants, like the pitcher plant, the Venus fly trap and the sundew, are carnivorous and consume insects. Some carnivorous fungi catch nematodes using either active traps in the form of constricting rings, or passive traps with adhesive structures. Many species of protozoa and bacteria prey on other microorganisms. Among freshwater and marine zooplankton, whether single-celled or multi-cellular, predatory grazing on phytoplankton and smaller zooplankton is common, found in many species of nanoflagellates, ciliates, rotifers, a diverse range of meroplankton animal larvae, two groups of crustaceans, namely copepods and cladocerans. To feed, a predator must search for and kill its prey; these actions form a foraging cycle. The predator must decide. If it chooses pursuit, its physical capabilities determine the mode of pursuit. Having captured the prey, it may need to expend energy handling it (e.g. killing it, removing any shell or