Elasmobranchii

Elasmobranchii is the cartilaginous-fish group that includes sharks, rays, and skates. Its members have skeletons made primarily of cartilage and multiple exposed gill slits.

Chondrichthyes: Chondrichthyes is the class of cartilaginous fishes, including elasmobranchs and chimaeras. Elasmobranchii is one of the two major living groups within this broader class.
Shark skin: Shark skin is covered in dermal denticles, small toothlike scales that reduce drag and resist abrasion. Its surface structures show how elasmobranch skin combines protection with hydrodynamic effects.
Shark finning: Shark finning is the removal of a shark's fins, often followed by discarding its body at sea. It is a major source of fishing pressure on many shark populations.
Great white shark: The great white shark is a large predatory shark found in coastal and offshore waters worldwide. It is a familiar example of a shark within Elasmobranchii.
Shark population decline: Shark population decline is the reduction of shark abundance caused by fishing, habitat change, and other pressures. Assessing trends is difficult where long-term monitoring and catch records are limited.
Chimaera: Chimaeras are cartilaginous fishes with upper jaws fused to the skull and a single external gill opening on each side. They are the other major living chondrichthyan group, distinct from elasmobranchs.
Electroreception: Electroreception is the detection of electric fields by specialized sensory systems. Elasmobranch ampullae are among the best-known examples of this sense in vertebrates.
Bycatch: Bycatch is the unintended capture of organisms during fishing for other species. Sharks and rays are frequently caught in nets and longlines targeting other animals.
Whale shark: The whale shark is the largest living fish and a filter-feeding shark. Its size and plankton-feeding lifestyle demonstrate the diversity of shark ecology.
Elasmobranch phylogeny: Elasmobranch phylogeny is the study of evolutionary relationships among sharks and rays. Molecular and anatomical evidence continue to refine how major lineages are related.

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