Vertebrate Geological Periods, BIO 3220

GEOLOGICAL PERIODS – # are millions of years ago


(age of mammals; 65 million yrs. duration)

Quaternary Period 2-4

 Holocene Epoch

modern species/subspecies

 Pleistocene Epoch

modern mammal species

Tertiary Period 65

Pliocene Epoch

appearance modern mammal genera

 Miocene Epoch

rise of mammalian subfamilies

 Oligocene Epoch

rise of modern mammalian families

 Eocene Epoch

rise of modern orders of mammals

 Paleocene Epoch

dominance of archaic mammals


(age of reptiles; 185 million yrs. duration)

Cretaceous Period 145

extinction large reptiles

Jurassic Period 210

reptiles dominant; first birds; arc. mammals

Triassic Period 245

first dinosaurs, turtles, mammals


(350 million yrs. duration)

Permian Period 290

primitive reptiles, decline of early amphibians

Carboniferous Period 360

amphibians dominant; first reptiles

Devonian Period 410

age of fishes; first amphibians

Silurian Period 440

archaic fishes

Ordovician Period 500

appearance of vertebrates (ostracoderms)

Cambrian Period 600

appearance of all major invertebrate phyla