Cretaceous Period

The Cretaceous Period is the period of time from about 140 million to 65 million years ago (ages vary). Associated with it are warmer global temperatures and no major glaciers, which enabled the survival of large reptile dinosaurs such as the Tyrannosaurus rex and the Triceratops. It is also the time of the appearance of modern insects, flowering plants, and new mammal species.
       
  Period Millions of Years Ago Life Forms
Ceneozoic Quaternary 1.8 Man, mammals, 
Neogene 24 - 1.8 First hominids, horses, canine
Paleogene 65 - 24 tapirs, rodents
Mesozoic Cretaceous 146 - 65 marine invertebrates, marsupials, pterosaurs
Jurassic 208 - 146 Suaropods, birds, flowering plants
Triassic 248 - 248 First mammals, turtles, ichtyosaur
Paleozoic Permian 280 - 248 Amphibians and reptiles
Pennsylvanian 325 - 280 First reptiles, ferns, cockroaches
Mississippian 360 - 325 First winged insects
Devonian 408 - 360 Fish and land plants
Silurian 438-408 First jawed fishes, first insects
Ordovician 505 - 438 First primitive plants, corals, fungi
Cambrian 575 - 500 Trilobites,mollusks, brachiopods

 

 

 

 
 
CARM ison