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Precambrian Period
Event 10: The presence of of stromatolites indicates that shallow seas covered much of Earth during intervals in this period. -
Period: to
DSalazar P.6
Geological Timescale -
Cambrian
Event 22: Trilobites appear. Event 23:Shelled brachiopods appear. Event 34: Ichthyosaurs are living in the ocean,new invertebrates call ammonite develop. -
Ordovician
Event 30: Colonies of tiny invertebrates call graptolites flourished and vertebrates appear, Fish did not have jaws or teeth and their bodies were covered with bony plates. Event 38: Environmental change causes mass extinction of sea invertebrates (trilobites amd eurypterids) as the seas retreats. -
Silurian
Event 24: Eurypterids (sea scorpions), sea stars and coral become more common. Event 33: Vascular land plants and animals, such as scorpions begin to evolve on land. Event 38: Environmental change causes mass extinction of sea invertebrates (trilobites and eurypterids) as the seas retreat. -
Devonian
Event 31: Huge plants began to develop, early amphibians form. Event 37: Age of fishes, fish that can breath out of the water and spend time on land form. -
Mississippian period
Event 2: Swamps and forests cover the land. -
Pennsylvanian Period
Event 4: Giant cockroaches appear. Event 15: Coal deposits form. -
Carboniferous
Event 21: Early reptiles resembling large ulizards appear. -
Permian
Event 35: Impact hypothesis- dinosaur mass exctinction -
Triassic
Event 16: Welcome to the world of the dinosaur! Enter the squirrel sized dinosaur and the first forest dwelling mammals appear -
Jurassic
Event 13: Whoa those Dino's are getting big and dominate the land- lizard hipped and bird hipped appear- carnivores and herbivores arrive. -
Cretaceous
Event 7: Some scientists believe that human kind has cause mass extinctions of plant and animal species , polluted the oceans and altered the atmosphere. -
Paleocene
Event 12: First primates evolve. -
Eocene
Event 25: World Wide temperatures drop about 4 degrees Celsius ( 39.2 degrees Fahrenheit). -
Oligocene
Event 6: Himalayas develop due to uplifting caused by the Indian continent and Eurasian continents colliding. Event 27: Many early mammals became extinct, clams and snails flourish. -
Miocene
Event 32: Antartic ice caps begin to form. -
Pliocene
Event 18: Various species migrated between continents across land bridges. -
Pleistocene
Event 9: Homosapiens (modern human )appeared and are hunters -
Holocene
Event 28: Modern human developed agriculture and made tools from bronze and iron