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The Greenland shark has the longest known lifespan of all vertebrate species. [43] It is estimated that the species has a lifespan of at least 272 years, with the oldest individual estimated to be 392 ± 120 years of age. Estimates of age were made using radiocarbon dating of crystals within the lenses of their eyes. [44]
Elegestolepis. Elegestolepis is a primitive shark from the Mongolepidida that lived during the Silurian and Devonian periods in Russia with only one species, E. grossi, known to date. [1] It was closely related to Mongolepis and Polymerolepis. It is only known from fragmentary placoid scales discovered in Russia before 1973. The oldest of these ...
The use of sight probably varies with species and water conditions. The shark's field of vision can swap between monocular and stereoscopic at any time. [58] A micro-spectrophotometry study of 17 species of sharks found 10 had only rod photoreceptors and no cone cells in their retinas giving them good night vision while making them colorblind.
It is the oldest known living human-planted tree in the world. [59] The Great sugi of Kayano, the cryptomeria deemed planted by humans in Kaga, Ishikawa, Japan, had an estimated age of 2,300 years in 1928. Jōmon Sugi, the cryptomeria naturally grown in Yakushima Island, Kagoshima, Japan, is 2,170 to 7,200 years old.
The first shark-like chondrichthyans appeared in the oceans 400 million years ago, [1] developing into the crown group of sharks by the Early Jurassic. [2] Listed below are extant species of shark. Sharks are spread across 512 described and 23 undescribed species in eight orders. The families and genera within the orders are listed in ...
The carpet sharks are a diverse group of sharks with differing sizes, appearances, diets, and habits. They first appeared in the fossil record in the Early Jurassic; the oldest known orectolobiform genera are Folipistrix (known from Toarcian to Aalenian of Belgium and Germany), Palaeobrachaelurus (Aalenian to Barremian) and Annea (Toarcian to ...
Megalodon. Otodus megalodon (/ ˈmɛɡələdɒn / MEG-əl-ə-don; meaning "big tooth"), commonly known as megalodon, is an extinct species of giant mackerel shark that lived approximately 23 to 3.6 million years ago (Mya), from the Early Miocene to the Early Pliocene epochs.
The three known genera are: Elegestolepis, [3] Mongolepis [4] and Polymerolepis. [5] [2] [6] [7] They are only known from fragmentary placoid scales, so their appearance is unknown. The oldest of these scales have been dated back to the Ludlow epoch (427.4 Ma to 423 Ma), making the members of the Mongolepidida possibly the oldest sharks known ...