geologic time time scale app?. precambrain longest era longest era earth was inhospitable earth was...
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PRECAMBRAINPRECAMBRAIN Longest eraLongest era Earth was inhospitableEarth was inhospitable
Still coolingStill cooling No atmosphereNo atmosphere
STROMATOLITESSTROMATOLITES
Oldest known fossilOldest known fossil 3.5 billion years3.5 billion years cynobacteriacynobacteria Began producing Began producing
oxygenoxygen Simple cell- no nucleusSimple cell- no nucleus
PALEOZOICPALEOZOIC
Life flourishes in the Life flourishes in the oceanocean
Trilobites dominate eraTrilobites dominate era
CambrianCambrian
Multi-cellular life in seas beginMulti-cellular life in seas begin First shellsFirst shells
SILURIANSILURIAN
First land plantsFirst land plants Fern-likeFern-like
Sea life continues to Sea life continues to flourishflourish
ammonite
CarboniferousCarboniferous(Mississippian & Pennsylvanian)(Mississippian & Pennsylvanian)
swampyswampy Huge insectsHuge insects Eventually created coal Eventually created coal
depositsdeposits
PERMIANPERMIAN
ReptilesReptiles First amphibiansFirst amphibians Life in sea and land Life in sea and land
thrivingthriving
MASS EXTINCTIONMASS EXTINCTION
THE GREAT DYINGTHE GREAT DYING
80% of species went extinct!80% of species went extinct!
What happened?What happened?
Climate got hotterClimate got hotter Siberian trapsSiberian traps
volcanoes = COvolcanoes = CO22
TRIASSICTRIASSIC
Beginning of dinosaursBeginning of dinosaurs Many smallMany small Primitive mammalsPrimitive mammals
CRETACEOUSCRETACEOUS
Intelligent dinosaurs (T-Intelligent dinosaurs (T-rex, raptors)rex, raptors)
First flowering plantsFirst flowering plants Carnivorous mammalsCarnivorous mammals
Asteroid theoryAsteroid theory
Asteroid caused climate changeAsteroid caused climate change 11stst- dust blocked out sun- dust blocked out sun 22ndnd- trapped in heat- trapped in heat
Evidence for asteroid theory?Evidence for asteroid theory?
CraterCrater IrridiumIrridium
Found in space rocksFound in space rocks Shocked quartzShocked quartz
QUATERNARYQUATERNARY
ice ages ice ages Mammoths/mastodonsMammoths/mastodons NeanderthalsNeanderthals
presentpresent
When will a new geologic time period start?When will a new geologic time period start?