Vertebrates:

550 mya: Agnatha (jawless vertebrates): Myxini (hagfishes) and Petromyzontida (lampreys)

439 mya: Gnathostomata (jawed vertebrates):

439 mya: Chondrichthyes (cartilaginous fishes): sharks, rays, and chimaeras

425 mya: Osteichthyes (bony fish):

425 mya: Actinopterygii (ray-finned fish) constitutes nearly 99% of over 30,000 living species of fish

425 mya: Sarcopterygii (lobe-finned 'fish'): coelacanths, lungfish and Tetrapoda:

380 mya: Tetrapoda (four-limbed vertebrates):

380 mya: Amphibia: frogs, salamanders and caecilians

315 mya: Sauria (or reptiles in general):

250 mya: Lepidosauromorpha: tuatara, lizards, snakes

250 mya: Archelosauria: turtles, crocodilians, dinosaurs (birds: 100 mya)

225 mya: Mammalia

red: warm-blooded

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