Outline of sharks

The following outline is provided as an overview of and topical guide to sharks:

Sharks (superorder Selachimorpha) – a type of fish with a full cartilaginous skeleton and a highly streamlined body. The earliest known sharks date from more than 420 million years ago, before the time of the dinosaurs.^[1]

Fields that study sharks

Ichthyology – branch of zoology devoted to fish (including sharks)
Meristics – branch of ichthyology that relates to counting features of fish, such as the number of fins or scales

What is a shark?

A shark, also called a "selachimorph", can be described as all of the following:

Animal – multicellular, eukaryotic organism of the kingdom Animalia or Metazoa. An animal's body plan eventually becomes fixed as it develops, although some types of animal undergo a process of metamorphosis later on in their life. Most kinds of animal are motile, meaning they can move spontaneously and independently.
- Chordate – Chordates (phylum Chordata) are animals which are either vertebrates or one of several closely related invertebrates.
  - Fish – gill-bearing aquatic vertebrate (or craniate) animal that lacks limbs with digits.
    - Chondrichthye (cartilaginous fish) – jawed fish with paired fins, paired nares, scales, two-chambered hearts, and skeletons made of cartilage rather than bone.
      - Elasmobranch – member of the subclass Elasmobranchii, which includes sharks, rays, and skates.
Predator – organism that attacks and feeds on prey (the organism that is attacked).^[2]
- Apex predator – some shark species are apex predators, that is, predators with no predators of their own, residing at the top of their food chain.^[3]

Biological classification

Kingdom: Animalia
Phylum: Chordata
Class: Chondrichthyes
Subclass: Elasmobranchii
Superorder: Selachimorpha

Types of sharks

Subdivisions of the biological classification Selachimorpha include:

Carcharhiniformes – groundsharks
Heterodontiformes – bullhead sharks
Hexanchiformes – the five extant species of the most primitive types of sharks
Lamniformes – mackerel sharks
Orectolobiformes – includes carpet sharks, including zebra sharks, nurse sharks, wobbegongs and whale shark
Pristiophoriformes – includes sawsharks
Squaliformes – includes gulper sharks, bramble sharks, lantern sharks, rough sharks, sleeper sharks and dogfish sharks
Squatiniformes – angel sharks
† Symmoriida
† Cladoselachiformes
† Xenacanthida (Xenacantiformes)
† Iniopterygia
† Eugeneodontida
† Hybodontiformes

Shark behavior

Photo of front page of newspaper showing photo of large shark with open mouth — The *Philadelphia Inquirer* report of Jersey Shore shark attack.

Predation
- Apex predator
Shark threat display – Behaviour shown by some sharks when threatened
Spy hopping – Raising the head out of the water

Shark attacks

International Shark Attack File
List of fatal, unprovoked shark attacks in the United States
Jersey Shore shark attacks of 1916 – series of shark attacks along the coast of New Jersey between July 1 and July 12, 1916^[4]
Summer of the Shark – the name given to the summer of 2001 by American media outlets capitalizing on a bull shark attack and subsequent shark attacks ^[5]

Range and habitats of sharks

Range

Bodies of water in which sharks can be found include:
- Seas: all
- Freshwater – some species of shark can live both in seawater and freshwater, and include:
Depths: from the surface down to depths of 2,000 metres (6,600 ft).

Habitats

White Shark Cafe – remote mid-Pacific Ocean area noted as a winter and spring habitat of otherwise coastal great white sharks

Sharks in captivity

Shark tank
Shark tunnel – underwater tunnel that passes through an aquarium that keeps sharks

Shark anatomy

Physical characteristics of sharks – shark skeleton, respiration and skin
- Dermal denticle – small outgrowths which cover the skin of sharks
- Ampullae of Lorenzini – sensing organ that helps sharks and fish to sense electric fields
- Electroreception – the biological ability to perceive electrical impulses (see also Ampullae of Lorenzini)
- Lateral line – sense organ that detects movement and vibration in the surrounding water
- Shark cartilage – material that a sharks' skeleton is composed of
- Shark teeth
- Spiracle – pumps water across gills
- Clasper – the anatomical structure that male sharks use for mating
- Fish anatomy – generic description of fish anatomy

Protective equipment

Drum lines
Shark net – submerged net placed around beaches to reduce shark attacks on swimmers
Shark proof cage – cage from which a SCUBA diver can examine sharks more safely
Shark repellent – method of driving sharks from an area, object, person, or animal
- Magnetic shark repellent – use of permanent magnet to repel sharks
- Protective Oceanic Device – first successful electronic shark repellent
Shark suit

Shark fishing

Drivers of the shark trade
Land-based shark fishing – fishing for sharks from land such as a beach, shoreline, jetty, pier, or bridge
Shark finning–the removal of shark fins for commercial purposes

Shark conservation

Shark Trust logo

1992 Cageless shark-diving expedition – 1st publicized cageless dive with great white sharks which contributed to changing public opinions about the supposed "killing machine"
Shark Alliance – coalition of non-governmental organizations dedicated to restoring and conserving shark populations by improving European fishing policy
Shark Conservation Act – Proposed US law to protect sharks
Shark sanctuary – Palau's first-ever attempt to prohibit taking sharks within its territorial waters
Shark tourism – form of ecotourism showcasing sharks
Shark Trust – A UK organisation for conservation of sharks

Notable sharks

Stronsay Beast – large, dead creature washed ashore on Stronsay, in the Orkney Islands, after a storm in 1808, later presumed to be a basking shark

Notable researchers and people

Peter Benchley – author of the novel Jaws, later worked for shark conservation
Jacques-Yves Cousteau – French naval officer, explorer, ecologist, filmmaker, innovator, scientist, photographer, author and researcher who studied the sea and all forms of life in water including sharks
Eugenie Clark – American ichthyologist researching poisonous fish and the behavior of sharks; popularly known as The Shark Lady
Leonard Compagno – international authority on shark taxonomy, best known for 1984 catalog of shark species (FAO)
Ben Cropp – Australian former shark hunter, who stopped in 1962 to produced some 150 wildlife documentaries
Richard Ellis – American marine biologist, author, and illustrator.
Rodney Fox – Australian film maker, conservationist, survivor of great white shark attack and one of the world's foremost authorities on them
Andre Hartman – South African diving guide best known for free-diving unprotected with great white sharks
Hans Hass – diving pioneer, known for shark documentaries
Mike Rutzen – great white shark expert and outspoken champion of shark conservation; known for free diving unprotected with great white sharks
Ron & Valerie Taylor – ex-spearfishing champions who switched from killing to filming underwater documentaries

References

^ Martin, R. Aidan. "Geologic Time". ReefQuest. Retrieved 2006-09-09.
^ Begon, M., Townsend, C., Harper, J. (1996). Ecology: Individuals, populations and communities (Third edition). Blackwell Science, London. ISBN 0-86542-845-X, ISBN 0-632-03801-2, ISBN 0-632-04393-8.
^ "apex predator". PBS. Retrieved 2010-01-25.
^ Fernicola, Twelve Days of Terror
^ "Summer of the Shark". Time. July 30, 2001. Retrieved May 20, 2010.

External links

Taxonomy of sharks and rays

[RQGT-1] Martin, R. Aidan. "Geologic Time". ReefQuest. Retrieved 2006-09-09.

[Ecology-2] Begon, M., Townsend, C., Harper, J. (1996). Ecology: Individuals, populations and communities (Third edition). Blackwell Science, London. ISBN 0-86542-845-X, ISBN 0-632-03801-2, ISBN 0-632-04393-8.

[3] "apex predator". PBS. Retrieved 2010-01-25.

[4] Fernicola, Twelve Days of Terror

[5] "Summer of the Shark". Time. July 30, 2001. Retrieved May 20, 2010.

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