-
Precambrian 4600
11) Nearly half of the valuable mineral deposits in the world occur in the rocks of this period. 21) Early reptiles resembling large lizards appear. -
Period: to
J Brazer Period 8
Geological Timescale -
Cambrian 542
10) The presence of stromatolites indicates that shallow seas covered much of Earth during intervals this period. 22) Trilobites appear. -
Ordovician 488
30) Colonies of tiny invertebrates called graptolites flourished and vertebrates appear, fish did not have jaws or teeth and their bodies were covered with tiny bony plates. 1) There is very little plant life during this period. -
Silurian 444
33) Vascular land plants and animals, such as scorpions begin to evolve on land. 24) Eurypterids, sea stars and coral become more common. -
Devonian 416
37) Age of fishes, fish that can breath out of the water and spend time on land form. 31) Huge plants begin to develop, early amphibians form. -
Mississippian 359
2) Swamps and forests cover the land. 23) Shelled brachiopods appear. -
Pennsylvanian 318
4) Giant cockroaches appear. 15) Coal deposits form. -
Permian 299
38) Environmental change causes mass extinction of sea invertebrates as the seas retreat. 8) Appalachian Mountains are created because of the collision of tectonic plates and savannahs form. -
Triassic 251
16) Welcome to the world of Dinosaur! Enter the squirrel sized dinosaur and the first forest dwelling mammals appear. 34) Ichthyosaurs are living in the ocean, new invertebrates called ammonite develop. -
Jurassic 200
13) Whoa those dinos are getting big and dominate the land- Lizard hipped and bird-hipped appear - carnivore and herbivores have arrived. 3) Flying reptiles calle pterosaurs are in the air now. -
Cretaceous 146
35) Impact hypothesis- dinosaur mass extinction. 5) First flowering plants appear- angiosperm. -
Paleocene 65.5
12) First primates evolve. 29) Small rodents evolve. -
Eocene 55.8
25) World wide temperatures drop about 4 degrees celsius. 17) Flying squirrels, whales and bats appear. -
Oligocene 33.9
6) Himalayas develop due to uplifting caused by the Indian subcontinent and Eurasian continents colliding. 27) Many early mammal became extinct, clams and snails flourish. -
Miocene 23
36) Mediterranean Sea dries up and refills several times due to tectonic forces and dropping sea levels. 32) Antarctic icecaps begin to form. -
Pliocene 5.3
18) Various species migrated between continents across land bridges. 26) First modern horses appear. -
Pleistocene 1.8
9) Homosapien appeared and are hunters. 20) Species that did not evolve to survive extreme cold moved to warmer climate areas or became extinct. -
Holocene 0.0115
19) The last glacial period ended and sea levels rose, Great Lakes formed. 28) Modern human developed agriculture and used tools made of bronze and iron. -
Anthropocene
7) Some scientists believe that human kind has caused mass extinctions of plant and animal species, polluted the oceans and altered the atmosphere. 14) There is argument as to when this epoch began, some scientists think it began with the industrial age in the early 1800's others think it began with the atomic age in the 1950's.
