Portal:Sharks

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Welcome to the shark portal!

Sharks are a group of elasmobranch fish characterized by a cartilaginous skeleton, five to seven gill slits on the sides of the head, and pectoral fins that are not fused to the head. Modern sharks are classified within the clade Selachimorpha (or Selachii) and are the sister group to the rays. However, the term "shark" has also been used to refer to all extinct members of Chondrichthyes with a shark-like morphology, such as hybodonts and xenacanths.

The oldest modern sharks are known from the Early Jurassic. They range in size from the small dwarf lanternshark (Etmopterus perryi), a deep sea species that is only 17 centimetres (6.7 in) in length, to the whale shark (Rhincodon typus), the largest fish in the world, which reaches approximately 12 metres (40 ft) in length. Sharks are found in all seas and are common to depths up to 2,000 metres (6,600 ft). They generally do not live in freshwater, although there are a few known exceptions, such as the bull shark and the river shark, which can be found in both seawater and freshwater. Sharks have a covering of dermal denticles that protects their skin from damage and parasites in addition to improving their fluid dynamics. They have numerous sets of replaceable teeth.

Several species are apex predators, which are organisms that are at the top of their food chain. Select examples include the tiger shark, blue shark, great white shark, mako shark, thresher shark, and hammerhead shark. (Full article...)

Selected article -

The finetooth shark, Carcharhinus isodon, is a species of requiem shark, family Carcharhinidae, found in the western Atlantic Ocean from North Carolina to Brazil. It forms large schools in shallow, coastal waters and migrates seasonally following warm water. A relatively small, slender-bodied shark, the finetooth shark can be identified by its needle-like teeth, dark blue-gray dorsal coloration, and long gill slits. It attains a maximum length of 1.9 m (6.2 ft). The diet of this species consists primarily of small bony fishes, in particular menhaden. Like other members of its family, it is viviparous in reproduction; every other year, females give birth to 2–6 pups in estuarine nursery areas. The finetooth shark is important to the gillnet shark fishery operating off the southeastern United States; the meat is sold for human consumption. Its population has not yet been depleted, but the US National Marine Fisheries Service (NMFS) has determined that fishing is occurring at unsustainable levels.

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Sharks
Sharks by order
Shark families
Shark genera
Sharks in art
Shark attacks
Shark conservation
Extinct sharks
Fictional sharks
Films about sharks
Shark stubs

WikiProjects

WikiProjects related to sharks:

  • WikiProject Science
    • WikiProject Biology
      • WikiProject Tree of Life
        • WikiProject Animals
          • WikiProject Fishes
            • WikiProject Sharks
  • WikiProject Aquarium Fishes
  • WikiProject Fishing

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The blacktip reef shark is a species of requiem shark, family Carcharhinidae, easily identified by the prominent black tips on its fins. It is among the most abundant sharks inhabiting the tropical coral reefs of the Indian and Pacific Oceans, and prefers shallow, inshore waters.

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General images

The following are images from various shark-related articles on Wikipedia.
  • Clear agonistic behaviour observed in Great White Shark (from Shark agonistic display)
  • A sign at Pyramid Rock Beach in Hawaii warning about a shark sighting, 2015 (from Shark tourism)
  • Postural elements of the agonistic display of the Gray Reef Shark (from Shark agonistic display)
  • Anti-cull protesters on Perth's Cottesloe Beach in Western Australia in 2014 (from Shark culling)
  • Shark Anatomy (50693674756) (from Shark anatomy)
  • The major features of sharks (from Shark anatomy)
  • A dissected view of the unique four-chambered heart of the sharkChambers: Sinus Venosus, Atrium, Ventricle, Conus Ateriosus (from Shark anatomy)
  • White shark cage diving near Gansbaai in South Africa (2015) (from Shark cage diving)
  • Lateral and Cross Section View of Shark Red and White Locomotor Muscles (from Shark anatomy)
  • The gill slits of a whale shark flaring as it expels water from its pharyngeal cavity. (from Shark anatomy)
  • Great white shark cages at Isla Guadalupe, Mexico (from Shark cage diving)
  • Placoid Scale (from Shark anatomy)
  • Shark cage diving (from Shark tourism)
  • Great white shark at Isla Guadalupe, Mexico, August 2006. Animal estimated at 11-12 feet (3.3 to 3.6 m) in length, age unknown (from Shark tourism)
  • Distribution of highly sensitive ampullae of Lorenzini across the shark's head and rostrum. (from Shark agonistic display)
  • Dorsal fin diagram with landmarks labeled. (from Shark anatomy)
  • Sharksucker (Echeneis naucrates) (from Shark agonistic display)
  • Postural configuration of a Gray Reef Shark as it displays agonistic behaviour, in a sculpture (from Shark agonistic display)
  • Sharks swimming outside shark-proof cage with people inside. (from Shark cage diving)
  • A 14-foot (4.3 m), 1,200-pound (540 kg) tiger shark caught in Kāne'ohe Bay, Oahu, in 1966
  • A ventral dissection of a pregnant female dogshark exposing its internal gill slits and internal spiracles. (from Shark anatomy)
  • This grey reef shark demonstrates countershading, with its darker dorsal surface and lighter ventral surface. (from Shark anatomy)
  • Depiction of shark anatomy including eggs, pups, and the liver (from Shark anatomy)
  • In a milestone decision in 2013, CITES prohibited international trade in the fins of the scalloped hammerhead (pictured) and four other shark species. (from List of threatened sharks)
  • BranchiostomaLanceolatum PioM (from Shark anatomy)
  • The whale shark, the world's largest fish, is classified as Endangered.
    Binding legislation and harvest management strategies... are urgently needed to address the disproportionate impact of fisheries on cartilaginous fishes.
    – IUCN global study 2010
    (from List of threatened sharks)

Topics

Shark · Outline of sharks
Shark orders
Carcharhiniformes (groundsharks) · Cladoselachiformes (extinct) · Eugeneodontida (extinct) · Heterodontiformes (bullhead sharks) · Hexanchiformes (most primitive sharks) · Hybodontiformes (extinct) · Iniopterygia (extinct) · Lamniformes (mackerel sharks) · Orectolobiformes (carpet sharks and relatives) · Pristiophoriformes (sawsharks and relatives) · Squaliformes (gulper sharks, bramble sharks, lantern sharks, rough sharks, sleeper sharks, dogfish sharks and relatives) · Squatiniformes (angel sharks) · Symmoriida (extinct) · Xenacanthida (also known as Xenacantiformes, extinct)


Major species
Basking shark · Blue shark · Bull shark · Great hammerhead · Great white shark · Grey reef shark · Hammerhead shark · Megalodon · Megamouth shark · Nurse shark · Oceanic whitetip shark · Requiem shark · Scalloped hammerhead · Shortfin mako shark · Swellshark · Thresher shark · Tiger shark · Whale shark


Shark biology
Ampullae of Lorenzini · Mermaid's purses · Physical characteristics of sharks · Shark teeth · Shark threat display


Shark-human interaction
Attack (drum lines, International Shark Attack File, Jersey Shore shark attacks of 1916, list of fatal, unprovoked shark attacks in the United States, shark net, shark proof cage, shark suit, Summer of the Shark) · Captivity (shark tunnel) · Conservation (grey nurse shark conservation, Shark Alliance, Shark Conservation Act, Shark Trust) · Fishing (International Land-Based Shark Fishing Association, land-based shark fishing) · Products (shark cartilage, shark finning, shark fin soup, shark liver oil)

See also

For additional lists of marine life-related featured articles and good articles see:

Wikimedia

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