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Endangered (EN) species are considered to be facing a very high risk of extinction in the wild. In September 2016, the International Union for Conservation of Nature (IUCN) listed 643 endangered fish species. [1] Of all evaluated fish species, 4.2% are listed as endangered. The IUCN also lists ten fish subspecies as endangered.
The global assessment of freshwater animals on the International Union for Conservation of Nature’s (IUCN) Red List of Threatened Species evaluated the extinction risk of 23,496 freshwater ...
The first ancestors of fish, or animals that were probably closely related to fish, were Haikouichthys and Myllokunmingia. [ 6 ] [ 3 ] These two genera all appeared around 530 Mya . Unlike the other fauna that dominated the Cambrian, these groups had the basic vertebrate body plan : a notochord , rudimentary vertebrae, and a well-defined head ...
Critically endangered (CR) species face an extremely high risk of extinction in the wild. As of July 2017, the International Union for Conservation of Nature (IUCN) listed 1,000 critically endangered fish species, including 87 which are tagged as possibly extinct. [1] [2] Of all evaluated fish species, 3.0% are listed as critically endangered ...
The researchers examined around 23,500 species of dragonflies, fish, crabs and other animals that depend exclusively on freshwater ecosystems. They found that 24% were at risk of extinction – classified as vulnerable, endangered or critically endangered – due to compounding threats from pollution, dams, water extraction, agriculture ...
Researchers assessed the status of 23,496 species of freshwater animals in groups including fishes, crustaceans such as crabs, crayfish and shrimp and insects such as dragonflies and damselflies ...
The evolution of fishes took place over a timeline which spans the Cambrian to the Cenozoic, including during that time in particular the Devonian, which has been dubbed the "age of fishes" for the many changes during that period. The Late Devonian extinctions played a crucial role in shaping the evolution of fish, or vertebrates in general. [1]
A fish (pl.: fish or fishes) is an aquatic, anamniotic, gill-bearing vertebrate animal with swimming fins and a hard skull, but lacking limbs with digits.Fish can be grouped into the more basal jawless fish and the more common jawed fish, the latter including all living cartilaginous and bony fish, as well as the extinct placoderms and acanthodians.