Search results
Results From The WOW.Com Content Network
The thresher sharks have an extreme example of this tail in which the upper lobe has evolved into a weapon for stunning prey. Bottom-dwelling sharks such as catsharks and carpet sharks have tails with long upper lobes and virtually no lower lobe. The upper lobe is held at a very low angle, which sacrifices speed for maneuverability.
The value of shark fins for shark fin soup has led to an increase in shark catches where usually only the fins are taken, while the rest of the shark is discarded, typically into the sea; health concerns about BMAA in the fins now exists regarding consumption of the soup A 4.3-metre (14 ft), 540-kilogram (1,200 lb) tiger shark caught in Kāne ...
Until that time, shark was generally an incidental catch rather than a targeted species. Flake rapidly became popular. It has a mild flavour, a soft texture that nevertheless remains well-defined after cooking, and a clean white appearance. A special advantage is that flake has no bones, because sharks are cartilaginous.
Two marine biologists share 10 shark facts for kids, as well as why shark attacks happen and why sharks are essential to human survival.
For premium support please call: 800-290-4726 more ways to reach us
Cartilaginous fish, such as sharks and rays, have jaws and skeletons made of cartilage rather than bone. Megalodon is an extinct species of shark that lived about 28 to 1.5 Ma. It looked much like a stocky version of the great white shark, but was much larger with fossil lengths reaching 20.3 metres (67 ft). [10]
This complex primitive pattern has, however, been simplified to various degrees in the great majority of vertebrates, as bones have either fused or vanished entirely. In teleosts, only the dentary, articular, and angular bones remain. [11] Cartilaginous fish, such as sharks, do
Cartilaginous fish (sharks and rays) have a more advanced immune system. They have three specialized organs that are unique to chondrichthyes; the epigonal organs (lymphoid tissues similar to mammalian bone) that surround the gonads, the Leydig's organ within the walls of their esophagus, and a spiral valve in their intestine. These organs ...