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Evolution of fish

Fish began evolving about 530 million years ago during the Cambrian explosion. It was during this time that the early chordates developed the skull and the vertebral column, leading to the first craniates and vertebrates. The first fish lineages belong to the Agnatha, or jawless fish. Early examples include Haikouichthys. During the late Cambrian…

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Jawless fish, Jawed fish & Overview

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Overview

Jawless fish

Jawed fish

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Evolution of fish

Nodes170
Edges169
Triples6
Avg. degree1.99
Density0.011765
Components1

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Important terminology

fish vertebrates devonian bony ostracoderms first lobe-finned early sharks silurian late evolved jawless placoderms known jawed appeared armoured mya conodonts

Entity relationships Subject–Predicate–Object triples

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SubjectPredicateObjectConfidenceSrc
the presence of a backboneinstance ofrather than purely on physical traits0.80text
catfishinstance ofHe compared them at first with extant armored fish0.80text
sturgeons but laterinstance ofHe compared them at first with extant armored fish0.80text
realizing that they had no movable jawsinstance ofHe compared them at first with extant armored fish0.80text
classified them in 1844 into a new groupinstance ofHe compared them at first with extant armored fish0.80text
the coelacanths show a strong similarity to the expected ancestral form of tetrapod limbsinstance ofThe fin-limbs of lobe-finned fish0.80text

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