Crocodile shark in a 1936 issue of "Zoological Magazine (Tokyo)" by ichthyologist Kiyomatsu Matsubara, based on a long specimen found at the Koti Fish Market in Japan. The type specimen is a long adult male found at a fish market in Su-ao, Taiwan. After being shuffled between the genera "Carcharias" and "Odontaspis" in the family Odontaspididae by various authors, in 1973 Leonard Compagno resurrected Jean Cadenat's 1963 subgenus "Pseudocarcharias" from synonymy for this species and placed it within its own family. The morphology of the crocodile shark suggests affinity with the megamouth shark (Megachasmidae), basking shark (Cetorhinidae), thresher sharks (Alopiidae), and mackerel
Fish intelligence is large and complex. In at least one important respect, it differs in internal structure from the mammalian cerebellum: The fish cerebellum does not contain discrete deep cerebellar nuclei. Instead, the primary targets of Purkinje cells are a distinct type of cell distributed across the cerebellar cortex, a type not seen in mammals. The circuits in the cerebellum are similar across all classes of vertebrates, including fish, reptiles, birds, and mammals. There is also an analogous brain structure in cephalopods with well-developed brains, such as octopuses. This has been taken as evidence that the cerebellum performs functions important to all