GEOLOGIC TIME SCALE

PRECAMBRIAN ERAPRECAMBRIAN ERA

5,000 – 544 MYA.The beginnings of

life, approximately 1,200 MYA.

Single and multiple celled organisms-lived in water.

5,000 – 544 MYA.The beginnings of

life, approximately 1,200 MYA.

Single and multiple celled organisms-lived in water.

CyanobacteriaCyanobacteria

prokaryote, no nucleus.

prokaryote, no nucleus.

PALEOZOIC ERAPALEOZOIC ERA

544 - 245 MYA. The evolution of life

in the sea and on land.

Divided into 7 Periods: Cambrian, Ordovician, Silurian, Devonian, Mississippian, Pennsylvanian, Permian.

544 - 245 MYA. The evolution of life

in the sea and on land.

Divided into 7 Periods: Cambrian, Ordovician, Silurian, Devonian, Mississippian, Pennsylvanian, Permian.

Cambrian periodCambrian period

544 – 505 MYA.544 – 505 MYA.

Cambrian periodCambrian period

Great variety of marine invertebrates.

Great variety of marine invertebrates.

Ordovician periodOrdovician period

438 – 505 MYA.First fish began to

appear.

438 – 505 MYA.First fish began to

appear.

Silurian periodSilurian period

408 – 438 MYA.First land plants

form.

408 – 438 MYA.First land plants

form.

CoralCoral

coral reefs & cephalopods abundant.

coral reefs & cephalopods abundant.

Devonian periodDevonian period

360 – 408 MYA.First land dwelling

creatures appear.First amphibians.

360 – 408 MYA.First land dwelling

creatures appear.First amphibians.

Devonian OceanDevonian Ocean

Mississippian periodMississippian period

320 – 360 MYA.Insects evolve.First fully

terrestrial creatures evolve.

320 – 360 MYA.Insects evolve.First fully

terrestrial creatures evolve.

Pennsylvanian PeriodPennsylvanian Period

286 – 320 MYA.Reptiles evolve.

286 – 320 MYA.Reptiles evolve.

Pennsylvanian Period Pennsylvanian Period

Swampy, future coal beds.

Swampy, future coal beds.

Permian periodPermian period

245 – 286 MYA.Largest mass extinctions. 90-95%

marine invertebrates became extinct.Reptiles getting bigger and stronger.

245 – 286 MYA.Largest mass extinctions. 90-95%

marine invertebrates became extinct.Reptiles getting bigger and stronger.

MESOZOIC ERAMESOZOIC ERA

“Age of the Dinosaurs”

66 – 245 MYA.Three periods:

Cretaceous, Jurassic, Triassic.

“Age of the Dinosaurs”

66 – 245 MYA.Three periods:

Cretaceous, Jurassic, Triassic.

Triassic PeriodTriassic Period

208 – 245 MYA.First mammals.Reptiles ruled.

208 – 245 MYA.First mammals.Reptiles ruled.

Jurassic PeriodJurassic Period

144 – 208 MYA.144 – 208 MYA.

Jurassic PeriodJurassic Period

Dinosaurs dominant.

Dinosaurs dominant.

Jurassic PeriodJurassic Period

First birds begin to appear.

First birds begin to appear.

Cretaceous PeriodCretaceous Period

66 – 144 MYA.Last period of

dinosaurs.Largest dinosaurs.

66 – 144 MYA.Last period of

dinosaurs.Largest dinosaurs.

CENOZOIC ERACENOZOIC ERA

Began at the extinction of the dinosaurs.

Present to 66 MYA.

Rise of the mammal.

Began at the extinction of the dinosaurs.

Present to 66 MYA.

Rise of the mammal.

Tertiary PeriodTertiary Period

1.5 – 66 MYA.Flowering plants

dominate.Mammals

dominate.

1.5 – 66 MYA.Flowering plants

dominate.Mammals

dominate.

Tertiary PeriodTertiary Period

Quaternary PeriodQuaternary Period

Present – 1.6 MYA.

Present – 1.6 MYA.

Quaternary PeriodQuaternary Period

Evolution of humans.

Evolution of humans.

Human evolutionHuman evolution

Extinctions and VariationsExtinctions and Variations