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The whale shark (Rhincodon typus) is a slow-moving, filter-feeding carpet shark and the largest known extant fish species. The largest confirmed individual had a length of 18.8 m (61.7 ft). [8] The whale shark holds many records for size in the animal kingdom, most notably being by far the most massive living non-cetacean animal.
Shark Anatomy (50693674756) The gill slits of a whale shark flaring as it expels water from its pharyngeal cavity. In the shark anatomy image, it depicts the beginning half of the shark, including the gills. The shark gills are especially important and were evolved from the chordate pharyngeal gill slits synapomorphy.
Cow sharks are considered the most primitive of all the sharks, because their skeletons resemble those of ancient extinct forms, with few modern adaptations. Their excretory and digestive systems are also unspecialised, suggesting that they may also resemble those of their primitive shark ancestors.
The effectiveness of the tissue varies, with some sharks having stronger nocturnal adaptations. Many sharks can contract and dilate their pupils, like humans, something no teleost fish can do. Sharks have eyelids, but they do not blink because the surrounding water cleans their eyes. To protect their eyes some species have nictitating membranes
The following outline is provided as an overview of and topical guide to sharks: Sharks (superorder Selachimorpha) are a type of fish with a full cartilaginous skeleton and a highly streamlined body. The earliest known sharks date from more than 440 million years ago, before the time of the dinosaurs. [1]
There is a wide diversity of sea life in the Maldives, with corals and over 2,000 species of fish, ranging from colourful reef fish to the blacktip reef shark, moray eels, and a wide variety of rays: manta ray, stingray, and eagle ray. The Maldivian waters are also home to the whale shark.
Since an appreciable fraction of this material was nutritious, rakers subsequently evolved as food-trapping mechanisms in filter feeders. Gill rakers, when long and closely set, play the same role in suspension-feeding fish such as herring, mullet, megamouth, basking and whale sharks, as baleen in the filter-feeding whales. [2]
They are commonly found attached to sharks, manta rays, whales, turtles, and dugongs, hence the common names "sharksucker" and "whalesucker". Smaller remoras also fasten onto fish such as tuna and swordfish , and some of the smallest remoras travel in the mouths or gills of large manta rays, ocean sunfish , swordfish and sailfish .