Outline of Historical Evolution
[click here for a detailed chart;  MYBP = Millions of years since beginning of interval]
Era Period MYBP Epochs MYBP Biology Geology
Cenozoic Quaternary     3 Holocene
Pleistocene		 0.4
  3		 Age of Humans Wisconsin Ice 7000 BP;
Cycles of glaciation

Tertiary   65 Pliocene
Miocene
Oligocene
Eocene
Paleocene		   5
 25
 38
 55
 65		 Hominidae 5 MYBP

Radiation of Mammalia & Aves;
Dominance of Teleosts

 N & S America join;

Continents assuming modern positions
Mesozoic Cretaceous 135

Massive extinctions

Origin of Angiosperms, colonial insects

 K/T Boundary event;
N America & Eurasia separate;
S America & Africa separate

Jurassic 215

Age of Dinosaurs;
Origin of Aves
Origin of Teleost fishes		 Breakup of Pangaea as Gondwanaland (S) 
& Laurasia (N)

Triassic 250

Gymnosperms dominant;
Origin of *Therapsida
Origin of Dinosaurs		 Continents adrift
Paleozoic Permian 290

"Great Dying":
>95% of marine invertebrates extinct		 Pangaea supercontinent & Tethys Sea

Carboniferous
[Pennsylvanian /
 Mississippian]		 360

Forests of tree ferns;

Age of Amphibia;
Origin of Amniota

 Origins of coal fields

Devonian 405

Abundant terrestrial life:
bryophytes, club mosses, Insecta

Age of Fishes;
Origin of Amphibia

 Pangaea coalescing

Silurian 435

Invasion of Land by Arthropoda & Trachaeophyta

Origin of Gnathostomata
*Ostracodermi dominant;
Origin of *Placodermi

Ordovician 505

Invertebrates dominate seas;
Trilobites dominant

Cambrian 570

Origin of Vertebrata

"Cambrian explosion":
Invertebrate phyla & algae abundant
Proterozoic
[Sinian]		 Vendian
Sturtian

....

 610
800

3800

Origin of Chordata (Pikaia)
 

Origins of Life
Archaeozoic
[Hadean]
4560

- Oldest rocks
l 
Text material © 2005 by Steven M. Carr