Entries here consist of Good and Featured articles, which meet a core set of high editorial standards.
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Stephanolepis cirrhifer
Stephanolepis cirrhifer, commonly known as the thread-sail filefish, is a species of marine fish in the family Monacanthidae. It is found in the western Pacific, in an area that ranges from northern Japan to the East China Sea, to Korea. The fish grows to a maximum length of about 12 inches (30 centimetres), and consumes both plant material and small marine organisms like skeleton shrimp. S. cirrhifer is host of the parasitePeniculus minuticaudae. Some minor genetic differentiation between S. cirrhifer born in the wild and those bred in a hatchery for consumer use has been shown. The fish is edible and sold commercially for culinary purposes in many Asian countries. (Full article...)
Livyatan is an extinctgenus of macroraptorial sperm whale containing one known species: L. melvillei. The genus name was inspired by the biblical sea monster Leviathan, and the species name by Herman Melville, the author of the famous novel Moby-Dick about a white bull sperm whale. Herman Melville often referred to whales as "Leviathans" in his book. It is mainly known from the Pisco Formation of Peru during the Tortonian stage of the Mioceneepoch, about 9.9–8.9 million years ago (mya); however, finds of isolated teeth from other locations such as Chile, Argentina, the United States (California), South Africa and Australia imply that either it or a close relative survived into the Pliocene, around 5mya, and may have had a global presence. It was a member of a group of macroraptorial sperm whales (or "raptorial sperm whales") and was probably an apex predator, preying on whales, seals and so forth. Characteristically of raptorial sperm whales, Livyatan had functional, enamel-coated teeth on the upper and lower jaws, as well as several features suitable for hunting large prey.
Livyatan's total length has been estimated to be about 13.5–17.5 m (44–57 ft), almost similar to that of the modern sperm whale (Physeter macrocephalus), making it one of the largest predators known to have existed. The teeth of Livyatan measured 36.2 cm (1.19 ft), and are the largest biting teeth of any known animal, excluding tusks. It is distinguished from the other raptorial sperm whales by the basin on the skull spanning the length of the snout. The spermaceti organ contained in that basin is thought to have been used in echolocation and communication, or for ramming prey and other sperm whales. The whale may have interacted with the large extinct shark megalodon (Otodus megalodon), competing with it for a similar food source. Its extinction was probably caused by a cooling event at the end of the Miocene period causing a reduction in food populations. The geological formation where the whale has been found has also preserved a large assemblage of marine life, such as sharks and marine mammals. (Full article...)
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X. bocki. Black arrow indicates side furrow. a is the anterior tip. p is the posterior tip. Black triangle indicates mouth. White triangle indicates circumferential furrow. The scale bar in the bottom right is 1 cm.
Xenoturbella bocki is a marine benthicworm-like species from the genus Xenoturbella. It is found in saltwater sea floor habitats off the coast of Europe, predominantly Sweden. It was the first species in the genus discovered. Initially it was collected by Swedish zoologist Sixten Bock in 1915, and described in 1949 by Swedish zoologist Einar Westblad. The unusual digestive structure of this species, in which a single opening is used to eat food and excrete waste, has led to considerable study and controversy as to its classification. It is a bottom-dwelling, burrowing carnivore that eats mollusks (likely larval forms, as opposed to hard-shelled adults). (Full article...)
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Crinoid on the reef of Batu Moncho Island, Indonesia
Crinoids are marine invertebrates that make up the classCrinoidea. Crinoids that remain attached to the sea floor by a stalk in their adult form are commonly called sea lilies, while the unstalked forms, called feather stars or comatulids, are members of the largest crinoid order, Comatulida. Crinoids are echinoderms in the phylumEchinodermata, which also includes the starfish, brittle stars, sea urchins and sea cucumbers. They live in both shallow water and in depths of over 9,000 metres (30,000 ft).
Adult crinoids are characterised by having the mouth located on the upper surface. This is surrounded by feeding arms, and is linked to a U-shaped gut, with the anus being located on the oral disc near the mouth. Although the basic echinoderm pattern of fivefold symmetry can be recognised, in most crinoids the five arms are subdivided into ten or more. These have feathery pinnules and are spread wide to gather planktonic particles from the water. At some stage in their lives, most crinoids have a short stem used to attach themselves to the substrate, but many live attached only as juveniles and become free-swimming as adults. (Full article...)
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Black coral colony
Antipatharians, also known as black corals or thorn corals, are an order of soft deep-water corals. These corals can be recognized by their jet-black or dark brown chitin skeletons, which are surrounded by their colored polyps (part of coral that is alive). Antipatharians are a cosmopolitan order, existing in nearly every oceanic location and depth, with the sole exception of brackish waters. However, they are most frequently found on continental slopes under 50 m (164 ft) deep. A black coral reproduces both sexually and asexually throughout its lifetime. Many black corals provide housing, shelter, food, and protection for other animals.
Black corals were originally classified in the subclass Ceriantipatharia along with ceriantharians (tube-dwelling anemones), but were later reclassified under Hexacorallia. Though they have historically been used by Pacific Islanders for medical treatment and in rituals, its only modern use is making jewelry. Black corals have been declining in numbers and are expected to continue declining due to the effects of poaching, ocean acidification and climate change. (Full article...)
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Pinnipedia is an infraorder of mammals in the orderCarnivora, composed of seals, sea lions, and the walrus. A member of this group is called a pinniped or a seal. They are widespread throughout the ocean and some larger lakes, primarily in colder waters. Pinnipeds range in size from the 1.1 m (3 ft 7 in) and 50 kg (110 lb) Baikal seal to the 6 m (20 ft) and 3,700 kg (8,200 lb) male southern elephant seal, which is also the largest member of Carnivora. Several species exhibit sexual dimorphism, such as the southern elephant seal, where the males can be more than three times as long and six times as massive as the females, or the Ross seal, which has females typically larger than the males. Four seal species are estimated to have over one million members, while six are classified as endangered with population counts as low as 600, and two, the Caribbean monk seal and the Japanese sea lion, went extinct in the 20th century.
The 34 extant species of Pinnipedia are split into 22 genera within 3 families: Odobenidae, comprising the walrus; Otariidae, the eared seals, split between the sea lions and fur seals; and Phocidae, the earless or true seals. Odobenidae and Otariidae are combined into the superfamilyOtarioidea, with Phocidae in Phocoidea. Extinct species have also been placed into the three extant families, as well as the extinct family Desmatophocidae, though most extinct species have not been categorized into a subfamily. Nearly one hundred extinct Pinnipedia species have been discovered, though due to ongoing research and discoveries the exact number and categorization is not fixed. (Full article...)
Thalassocnus evolved several marine adaptations over 4 million years, such as dense and heavy bones to counteract buoyancy, the internal nostrils migrating farther into the head to help with breathing while completely submerged, the snout becoming wider and more elongated to consume aquatic plants better, and the head angling farther and farther downwards to aid in bottom feeding. The long tail was probably used for diving and balance similar to the modern day beaver (Castor spp.) and platypus (Ornithorhynchus anatinus). (Full article...)
Whales are a widely distributed and diverse group of fully aquaticplacentalmarine mammals. As an informal and colloquial grouping, they correspond to large members of the infraorder Cetacea, i.e. all cetaceans apart from dolphins and porpoises. Dolphins and porpoises may be considered whales from a formal, cladistic perspective. Whales, dolphins and porpoises belong to the order Cetartiodactyla, which consists of even-toed ungulates. Their closest non-cetacean living relatives are the hippopotamuses, from which they and other cetaceans diverged about 54 million years ago. The two parvorders of whales, baleen whales (Mysticeti) and toothed whales (Odontoceti), are thought to have had their last common ancestor around 34 million years ago. Mysticetes include four extant (living) families: Balaenopteridae (the rorquals), Balaenidae (right whales), Cetotheriidae (the pygmy right whale), and Eschrichtiidae (the grey whale). Odontocetes include the Monodontidae (belugas and narwhals), Physeteridae (the sperm whale), Kogiidae (the dwarf and pygmy sperm whale), and Ziphiidae (the beaked whales), as well as the six families of dolphins and porpoises which are not considered whales in the informal sense.
Whales are fully aquatic, open-ocean animals: they can feed, mate, give birth, suckle and raise their young at sea. Whales range in size from the 2.6 metres (8.5 ft) and 135 kilograms (298 lb) dwarf sperm whale to the 29.9 metres (98 ft) and 190 tonnes (210 short tons) blue whale, which is the largest known animal that has ever lived. The sperm whale is the largest toothed predator on Earth. Several whale species exhibit sexual dimorphism, in that the females are larger than males. (Full article...)
Terropterus was the earliest known and largest mixopterid eurypterid. Fossil specimens referred to T. xiushanensis are estimated to have reached up to 40 centimeters (15.7 in) in length, but other fossils, either representing older T. xiushanensis or a second species of Terropterus, demonstrate that members of the genus could reach upwards of at least 100 centimeters (3.3 ft) in length. Terropterus is the only mixopterid known from the ancient southern continent of Gondwana, with the other two mixopterid genera, Mixopterus and Lanarkopterus, only being known from what was once the northern continent of Laurussia. The discovery of Terropterus significantly expanded the known geographical and temporal ranges of the Mixopteridae. (Full article...)
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Southern right whale breaching
Right whales are three species of large baleen whales of the genusEubalaena: the North Atlantic right whale (E. glacialis), the North Pacific right whale (E. japonica) and the Southern right whale (E. australis). They are classified in the family Balaenidae with the bowhead whale. Right whales have rotund bodies with arching rostrums, V-shaped blowholes and dark gray or black skin. The most distinguishing feature of a right whale is the rough patches of skin on its head, which appear white due to parasitism by whale lice. Right whales are typically 13–17 m (43–56 ft) long and weigh up to 100 short tons (91 t; 89 long tons) or more.
All three species are migratory, moving seasonally to feed or give birth. The warm equatorial waters form a barrier that isolates the northern and southern species from one another although the southern species, at least, has been known to cross the equator. In the Northern Hemisphere, right whales tend to avoid open waters and stay close to peninsulas and bays and on continental shelves, as these areas offer greater shelter and an abundance of their preferred foods. In the Southern Hemisphere, right whales feed far offshore in summer, but a large portion of the population occur in near-shore waters in winter. Right whales feed mainly on copepods but also consume krill and pteropods. They may forage the surface, underwater or even the ocean bottom. During courtship, males gather into large groups to compete for a single female, suggesting that sperm competition is an important factor in mating behavior. Gestation tends to last a year, and calves are weaned at eight months old. (Full article...)
The hammerhead sharks are a group of sharks that form the family Sphyrnidae, named for the unusual and distinctive form of their heads, which are flattened and laterally extended into a cephalofoil (a T-shape or "hammer"). The shark's eyes are placed one on each end of this T-shaped structure, with their small mouths directly centered and underneath. Most hammerhead species are placed in the genus Sphyrna, while the winghead shark is placed in its own genus, Eusphyra. Many different—but not necessarily mutually exclusive—functions have been postulated for the cephalofoil, including sensory reception, manoeuvering, and prey manipulation. The cephalofoil gives the shark superior binocular vision and depth perception.
Hammerheads are found worldwide, preferring life in warmer waters along coastlines and continental shelves. Unlike most sharks, some hammerhead species will congregate and swim in large schools during the day, becoming solitary hunters at night. (Full article...)
Image 2Cnidarians are the simplest animals with cells organised into tissues. Yet the starlet sea anemone contains the same genes as those that form the vertebrate head. (from Marine invertebrates)
Image 3Biomass pyramids. Compared to terrestrial biomass pyramids, aquatic pyramids are generally inverted at the base. (from Marine food web)
Different bacteria shapes (cocci, rods and spirochetes) and their sizes compared with the width of a human hair. A few bacteria are comma-shaped (vibrio). Archaea have similar shapes, though the archaeon Haloquadratum is flat and square.
The unit μm is a measurement of length, the micrometer, equal to 1/1,000 of a millimeter
Image 6Scanning electron micrograph of a strain of Roseobacter, a widespread and important genus of marine bacteria. For scale, the membrane pore size is 0.2μm in diameter. (from Marine prokaryotes)
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Diagram of a mycoloop (fungus loop)
Parasitic chytrids can transfer material from large inedible phytoplankton to zooplankton. Chytrids zoospores are excellent food for zooplankton in terms of size (2–5 μm in diameter), shape, nutritional quality (rich in polyunsaturated fatty acids and cholesterols). Large colonies of host phytoplankton may also be fragmented by chytrid infections and become edible to zooplankton. (from Marine fungi)
Image 10In the open ocean, sunlit surface epipelagic waters get enough light for photosynthesis, but there are often not enough nutrients. As a result, large areas contain little life apart from migrating animals. (from Marine habitat)
Image 12Estuaries occur when rivers flow into a coastal bay or inlet. They are nutrient rich and have a transition zone which moves from freshwater to saltwater. (from Marine habitat)
Image 18Cycling of marine phytoplankton. Phytoplankton live in the photic zone of the ocean, where photosynthesis is possible. During photosynthesis, they assimilate carbon dioxide and release oxygen. If solar radiation is too high, phytoplankton may fall victim to photodegradation. For growth, phytoplankton cells depend on nutrients, which enter the ocean by rivers, continental weathering, and glacial ice meltwater on the poles. Phytoplankton release dissolved organic carbon (DOC) into the ocean. Since phytoplankton are the basis of marine food webs, they serve as prey for zooplankton, fish larvae and other heterotrophic organisms. They can also be degraded by bacteria or by viral lysis. Although some phytoplankton cells, such as dinoflagellates, are able to migrate vertically, they are still incapable of actively moving against currents, so they slowly sink and ultimately fertilize the seafloor with dead cells and detritus. (from Marine food web)
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Model of the energy generating mechanism in marine bacteria
(1) When sunlight strikes a rhodopsin molecule (2) it changes its configuration so a proton is expelled from the cell (3) the chemical potential causes the proton to flow back to the cell (4) thus generating energy (5) in the form of adenosine triphosphate. (from Marine prokaryotes)
Image 21Chytrid parasites of marine diatoms. (A) Chytrid sporangia on Pleurosigma sp. The white arrow indicates the operculate discharge pore. (B) Rhizoids (white arrow) extending into diatom host. (C) Chlorophyll aggregates localized to infection sites (white arrows). (D and E) Single hosts bearing multiple zoosporangia at different stages of development. The white arrow in panel E highlights branching rhizoids. (F) Endobiotic chytrid-like sporangia within diatom frustule. Bars = 10 μm. (from Marine fungi)
Image 22Jellyfish are easy to capture and digest and may be more important as food sources than was previously thought. (from Marine food web)
Image 23Sea ice food web and the microbial loop. AAnP = aerobic anaerobic phototroph, DOC = dissolved organic carbon, DOM = dissolved organic matter, POC = particulate organic carbon, PR = proteorhodopsins. (from Marine food web)
Image 25The distribution of anthropogenic stressors faced by marine species threatened with extinction in various marine regions of the world. Numbers in the pie charts indicate the percentage contribution of an anthropogenic stressors' impact in a specific marine region. (from Marine food web)
Image 27The deep sea amphipodEurythenes plasticus, named after microplastics found in its body, demonstrating plastic pollution affects marine habitats even 6000m below sea level. (from Marine habitat)
Image 29Archaea were initially viewed as extremophiles living in harsh environments, such as the yellow archaea pictured here in a hot spring, but they have since been found in a much broader range of habitats. (from Marine prokaryotes)
Image 31This algae bloom occupies sunlit epipelagic waters off the southern coast of England. The algae are maybe feeding on nutrients from land runoff or upwellings at the edge of the continental shelf. (from Marine habitat)
Image 34Ernst Haeckel's 96th plate, showing some marine invertebrates. Marine invertebrates have a large variety of body plans, which are currently categorised into over 30 phyla. (from Marine invertebrates)
Image 35Tidepools on rocky shores make turbulent habitats for many forms of marine life (from Marine habitat)
Image 36Waves and currents shape the intertidal shoreline, eroding the softer rocks and transporting and grading loose particles into shingles, sand or mud (from Marine habitat)
Image 37Sponges have no nervous, digestive or circulatory system (from Marine invertebrates)
Image 38Schematic representation of the changes in abundance between trophic groups in a temperate rocky reef ecosystem. (a) Interactions at equilibrium. (b) Trophic cascade following disturbance. In this case, the otter is the dominant predator and the macroalgae are kelp. Arrows with positive (green, +) signs indicate positive effects on abundance while those with negative (red, -) indicate negative effects on abundance. The size of the bubbles represents the change in population abundance and associated altered interaction strength following disturbance. (from Marine food web)
Image 40Oceanic pelagic food web showing energy flow from micronekton to top predators. Line thickness is scaled to the proportion in the diet. (from Marine food web)
Image 46Phylogenetic tree representing bacterial OTUs from clone libraries and next-generation sequencing. OTUs from next-generation sequencing are displayed if the OTU contained more than two sequences in the unrarefied OTU table (3626 OTUs). (from Marine prokaryotes)
Image 52Reconstruction of an ammonite, a highly successful early cephalopod that first appeared in the Devonian (about 400 mya). They became extinct during the same extinction event that killed the land dinosaurs (about 66 mya). (from Marine invertebrates)
Image 54Common-enemy graph of Antarctic food web. Potter Cove 2018. Nodes represent basal species and links indirect interactions (shared predators). Node and link widths are proportional to number of shared predators. Node colors represent functional groups. (from Marine food web)
Image 58On average there are more than one million microbial cells in every drop of seawater, and their collective metabolisms not only recycle nutrients that can then be used by larger organisms but also catalyze key chemical transformations that maintain Earth's habitability. (from Marine food web)
Image 63Some lobe-finned fishes, like the extinct Tiktaalik, developed limb-like fins that could take them onto land (from Marine vertebrate)
Image 64The Ocean Cleanup is one of many organizations working toward marine conservation such at this interceptor vessel that prevents plastic from entering the ocean. (from Marine conservation)
Image 68Conceptual diagram of faunal community structure and food-web patterns along fluid-flux gradients within Guaymas seep and vent ecosystems. (from Marine food web)
Image 69Sandy shores provide shifting homes to many species (from Marine habitat)
Image 70Antarctic marine food web. Potter Cove 2018. Vertical position indicates trophic level and node widths are proportional to total degree (in and out). Node colors represent functional groups. (from Marine food web)
Image 71An in situ perspective of a deep pelagic food web derived from ROV-based observations of feeding, as represented by 20 broad taxonomic groupings. The linkages between predator to prey are coloured according to predator group origin, and loops indicate within-group feeding. The thickness of the lines or edges connecting food web components is scaled to the log of the number of unique ROV feeding observations across the years 1991–2016 between the two groups of animals. The different groups have eight colour-coded types according to main animal types as indicated by the legend and defined here: red, cephalopods; orange, crustaceans; light green, fish; dark green, medusa; purple, siphonophores; blue, ctenophores and grey, all other animals. In this plot, the vertical axis does not correspond to trophic level, because this metric is not readily estimated for all members. (from Marine food web)
Image 72Some representative ocean animal life (not drawn to scale) within their approximate depth-defined ecological habitats. Marine microorganisms exist on the surfaces and within the tissues and organs of the diverse life inhabiting the ocean, across all ocean habitats. (from Marine habitat)
Image 73Whales were close to extinction until legislation was put in place. (from Marine conservation)
Image 74Ocean surface chlorophyll concentrations in October 2019. The concentration of chlorophyll can be used as a proxy to indicate how many phytoplankton are present. Thus on this global map green indicates where a lot of phytoplankton are present, while blue indicates where few phytoplankton are present. – NASA Earth Observatory 2019. (from Marine food web)
Image 82Only 29 percent of the world surface is land. The rest is ocean, home to the marine habitats. The oceans are nearly four kilometres deep on average and are fringed with coastlines that run for nearly 380,000 kilometres.
Image 92Conference events, such as the events hosted by the United Nations, help to bring together many stakeholders for awareness and action. (from Marine conservation)
Image 93
Bacterioplankton and the pelagic marine food web
Solar radiation can have positive (+) or negative (−) effects resulting in increases or decreases in the heterotrophic activity of bacterioplankton. (from Marine prokaryotes)
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Estimates of microbial species counts in the three domains of life
Bacteria are the oldest and most biodiverse group, followed by Archaea and Fungi (the most recent groups). In 1998, before awareness of the extent of microbial life had gotten underway, Robert M. May estimated there were 3 million species of living organisms on the planet. But in 2016, Locey and Lennon estimated the number of microorganism species could be as high as 1 trillion. (from Marine prokaryotes)
Image 96A protected sea turtle area that warns of fines and imprisonment on a beach in Miami, Florida. (from Marine conservation)
Image 97A 2016 metagenomic representation of the tree of life using ribosomal protein sequences. The tree includes 92 named bacterial phyla, 26 archaeal phyla and five eukaryotic supergroups. Major lineages are assigned arbitrary colours and named in italics with well-characterized lineage names. Lineages lacking an isolated representative are highlighted with non-italicized names and red dots. (from Marine prokaryotes)
Image 98Topological positions versus mobility: (A) bottom-up groups (sessile and drifters), (B) groups at the top of the food web. Phyto, phytoplankton; MacroAlga, macroalgae; Proto, pelagic protozoa; Crus, Crustacea; PelBact, pelagic bacteria; Echino, Echinoderms; Amph, Amphipods; HerbFish, herbivorous fish; Zoopl, zooplankton; SuspFeed, suspension feeders; Polych, polychaetes; Mugil, Mugilidae; Gastropod, gastropods; Blenny, omnivorous blennies; Decapod, decapods; Dpunt, Diplodus puntazzo; Macropl, macroplankton; PlFish, planktivorous fish; Cephalopod, cephalopods; Mcarni, macrocarnivorous fish; Pisc, piscivorous fish; Bird, seabirds; InvFeed1 through InvFeed4, benthic invertebrate feeders. (from Marine food web)
Mycoloop links between phytoplankton and zooplankton
Chytrid‐mediated trophic links between phytoplankton and zooplankton (mycoloop). While small phytoplankton species can be grazed upon by zooplankton, large phytoplankton species constitute poorly edible or even inedible prey. Chytrid infections on large phytoplankton can induce changes in palatability, as a result of host aggregation (reduced edibility) or mechanistic fragmentation of cells or filaments (increased palatability). First, chytrid parasites extract and repack nutrients and energy from their hosts in form of readily edible zoospores. Second, infected and fragmented hosts including attached sporangia can also be ingested by grazers (i.e. concomitant predation). (from Marine fungi)
Image 101640 μm microplastic found in the deep sea amphipod Eurythenes plasticus (from Marine habitat)
Image 102Lampreys are often parasitic and have a toothed, funnel-like sucking mouth (from Marine vertebrate)
Image 108The pelagic food web, showing the central involvement of marine microorganisms in how the ocean imports nutrients from and then exports them back to the atmosphere and ocean floor (from Marine food web)
Image 112Food web structure in the euphotic zone. The linear food chain large phytoplankton-herbivore-predator (on the left with red arrow connections) has fewer levels than one with small phytoplankton at the base. The microbial loop refers to the flow from the dissolved organic carbon (DOC) via heterotrophic bacteria (Het. Bac.) and microzooplankton to predatory zooplankton (on the right with black solid arrows). Viruses play a major role in the mortality of phytoplankton and heterotrophic bacteria, and recycle organic carbon back to the DOC pool. Other sources of dissolved organic carbon (also dashed black arrows) includes exudation, sloppy feeding, etc. Particulate detritus pools and fluxes are not shown for simplicity. (from Marine food web)
Image 116Microplastics found in sediments on the seafloor (from Marine habitat)
Image 117Elevation-area graph showing the proportion of land area at given heights and the proportion of ocean area at given depths (from Marine habitat)
Image 125A microbial mat encrusted with iron oxide on the flank of a seamount can harbour microbial communities dominated by the iron-oxidizing Zetaproteobacteria (from Marine prokaryotes)
Image 23Global distribution of coral, mangrove, and seagrass diversity (from Marine ecosystem)
Image 24Ecosystem services delivered by epibenthicbivalve reefs. Reefs provide coastal protection through erosion control and shoreline stabilization, and modify the physical landscape by ecosystem engineering, thereby providing habitat for species by facilitative interactions with other habitats such as tidal flat benthic communities, seagrasses and marshes. (from Marine ecosystem)
Image 25Drivers of change in marine ecosystems (from Marine ecosystem)
Did you know (auto-generated)
... that Alexis Sharkey's last Instagram post before her murder documented her travels to Tulum, Mexico?
... that for 25 years after an attempt to explode a whale went awry, the Oregon TV station that filmed it regularly fielded requests for its footage?
... The teeth of carnivorous sharks are not attached to the jaw, but embedded in their flesh. In many species, teeth are constantly replaced throughout the shark's life.
... In Australia in 1935, a tiger shark vomited up a human arm. The shark had not killed anyone but had scavenged the arm after a murder victim had been cut up with a knife and thrown into sea.
... A typical shark has several hundred teeth at any one time.
... You have a greater chance of being struck by lightning, drowning in a bathtub, fatally falling down stairs, or dying from a bee sting than being killed by a shark.
... groups of bottlenose dolphinss around the Australian Pacific have displayed basic tool use by wrapping pieces of sponge around their beaks to prevent abrasions. This is a display of a cognitive process similar to that of great apess.