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An analysis of a partially complete tail fin fossil shows that Cretoxyrhina had a lunate (crescent-shaped) tail most similar with modern lamnid sharks, whale sharks, and basking sharks. The transition to tail vertebrae is estimated to be between the 140th and 160th vertebrae out of the total 230, resulting in a total tail vertebral count of 70 ...
Cosmopolitodus is an extinct genus of mackerel shark that lived between thirty and one million years ago during the late Oligocene to the Early Pleistocene epochs.Its type species is Cosmopolitodus hastalis, the broad-tooth mako (other common names include the extinct giant mako and broad-tooth white shark).
The 2007 film Sharkwater documents ways in which sharks are being hunted to extinction. [15] In 2009, the IUCN Shark Specialist Group reported on the conservation status of pelagic (open water) sharks and rays. They found that over half the pelagic sharks targeted by high-seas fisheries were threatened with extinction. [16] [17] [18]
Sharks could be facing extinction over the next couple of decades. Human interference is largely to blame for the species interference. Overfishing of sharks has increased as the global demand has ...
The fossils of Otodus sharks indicate that they were very large macro-predatory sharks. [7] The largest known teeth of O. obliquus measure about 104 millimetres (4.1 in) in height. [8] The vertebral centrum of this species are over 12.7 cm (5 inch) wide. [7] Scientists suggest that O. obliquus would have measured about 8–9 metres (26–30 ft ...
Hybodontiformes, commonly called hybodonts, are an extinct group of shark-like cartilaginous fish (chondrichthyans) which existed from the late Devonian to the Late Cretaceous. Hybodonts share a close common ancestry with modern sharks and rays (Neoselachii) as part of the clade Euselachii. They are distinguished from other chondrichthyans by ...
Xenacanthida (or Xenacanthiformes) is an order or superorder of extinct shark-like chondrichthyans (cartilaginous fish) known from the Carboniferous to Triassic. They were native to freshwater, marginal marine and shallow marine habitats. [1] Some xenacanths may have grown to lengths of 5 m (16 ft). [2]
Cretalamna is a genus of extinct otodontid shark that lived from the latest Early Cretaceous to Eocene epoch (about 103 to 46 million years ago). It is considered by many to be the ancestor of the largest sharks to have ever lived, such as Otodus angustidens , Otodus chubutensis , and Otodus megalodon .