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Coelacanth caught in 1974 Bony fish split their jaws into several bones and evolve lungs, fin bones, two pairs of rib bones, and opercular bones, and diverge into the actinopterygii (with ray fins) and the sarcopterygii (with fleshy, lower fins); [17] the latter transitioned from marine to freshwater habitats. Jawed fish also possess dorsal and ...
The evolution of fish began about 530 million years ago ... (including humans)—are known from the Middle ... The fins evolved into the legs of the first ...
The earliest known tracks on land named the Zachelmie trackways which are possibly related to icthyostegalians. [80] 375 Ma Tiktaalik, a lobe-finned fish with some anatomical features similar to early tetrapods. It has been suggested to be a transitional species between fish and tetrapods. [81] 365 Ma
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]
The largest known lobe-finned fish was Rhizodus hibberti from the Carboniferous period of Scotland which may have exceeded 7 meters in length. Among the two groups of living species, the coelacanths and the lungfishes , the largest species is the West Indian Ocean coelacanth , reaching 2 m (6 ft 7 in) in length and weighing up 110 kg (240 lb).
The coelacanth was long considered a "living fossil" because scientists thought it was the sole remaining member of a taxon otherwise known only from fossils, with no close relations alive, [8] and that it evolved into roughly its current form approximately 400 million years ago. [1]
The evolution of tetrapods began about 400 million years ago in the Devonian Period with the earliest tetrapods evolved from lobe-finned fishes. [1] Tetrapods (under the apomorphy-based definition used on this page) are categorized as animals in the biological superclass Tetrapoda, which includes all living and extinct amphibians, reptiles, birds, and mammals.
Osteichthyes (/ ˌ ɒ s t iː ˈ ɪ k θ iː z / ost-ee-IK-theez; from Ancient Greek ὀστέον (ostéon) 'bone' and ἰχθύς (ikhthús) 'fish'), [2] also known as osteichthyans or commonly referred to as the bony fish, is a diverse superclass of vertebrate animals that have endoskeletons primarily composed of bone tissue.