-
Precambrian Time
Trilobites appear, Shelled brachiopods appear -
Period: to
KBritton P:4
Geological Timescale -
Cambrian
There is very little plant life during this period, Nearly half of the valuable mineral deposits in the world occur in the rocks of thisperiod -
Ordovician
Colonies of tiny invertebrates called graptolites flourished and vertebrates appear, fish did not have jaws or teeth and their bodies were covered with bony plates, There is very little plant life durring this period -
Silurian
Coral deposits form, Eurypterids (sea scorpions), sea stars and coral become more common -
Devonian
Age of the fishes, Fish that can breath out of water and spend time on land form, -
Carboniferous
Coal deposits formed, Swamps and forests covered the land -
Permian
Appalachian Mountains are created because of the collision of tectonic plates & savannas form, -
Mesozoic
Early reptiles resembling large reptiles appeared, -
Triassic
Small rodents appear, Ichthyosaurs are living in the ocean, new invertebrates called ammonite develope -
Jurassic
Whoa those dinos are getting big & dominate the land - Lizard-hipped and bird-hipped appear - carnivores and herbivores have arrived, Flying reptiles called pterosaurs are in the air now -
Cretaceous
First flowering plants appear - angiosperm, Impact hypothesis - dinosaur mass extinction -
Paleocene
Small rodents evolve, The first primates appear -
Eocene
First modern horses appear, Flying squirrels, whales and bats appear -
Oligocere
World wide temperatures drop 4 degrees Celsius, -
Miocene
Many early mammals become extinct, clams and snailscflourish, -
Pliocene
First modern horses appear, Various species migrated between continents across land bridges -
Plestocene
Homosapians appear and hunt, Huge icecaps begin to form -
Holocene
Scientists state that we have caused a mass extinction by pouting the air and water, There is debate weather this period started in the 1800's or the 1950's
