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An abridged phylogeny of the vertebrates. Shown is the timing of major radiation events within the vertebrate lineage. Extinct lineages and some extant lineages (for example, coelacanths, lungfish and hagfish) have been omitted for simplicity. Here, reptile is synonymous with sauropsid, ray-finned fish is synonymous with actinopterygian, and osteichthyan is synonymous with euteleostome. CZ, Cenozoic; MYA, million years ago.
