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The fins evolved into the legs of the first tetrapod land vertebrates, amphibians. They also possess two dorsal fins with separate bases, as opposed to the single dorsal fin of ray-finned fish. The braincase of lobe-finned fish primitively has a hinge line, but this is lost in tetrapods and lungfish.
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]
A fish with limb-like fins that could take it onto land. [75] It is an example from several lines of ancient sarcopterygian fish developing adaptations to the oxygen-poor shallow-water habitats of its time, which led to the evolution of tetrapods. [61]
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.
Evolutionary theory says all animals that are walking on land actually evolved from sea-dwelling creatures at some point in the ancient past. To study this further, scientists from McGill ...
Eusthenopteron (from Greek: εὖ eû, 'good', Greek: σθένος sthénos, 'strength', and Greek: πτερόν pteron 'wing' or 'fin') [2] is a genus of prehistoric sarcopterygian (often called "lobe-finned") fish known from several species that lived during the Late Devonian period, about 385 million years ago.
Rhenanida ("Rhine fish") were flattened, ray-like, bottom-dwelling predators with large, upturned mouths that lived in marine environments. The rhenanids were once presumed to be the most primitive, or at least the closest to the ancestral placoderm, as their armour was made of unfused components—a mosaic of tubercles—as opposed to the ...
A handful of fossil teeth from a completely new species suggests the creatures emerged some 440 million years ago.