A Brief History of the A Brief History of the EarthEarth

TimescaleTimescale

• 7/8 of the entire period life has existed on 7/8 of the entire period life has existed on earth is known as the Precambrian era.earth is known as the Precambrian era.

• During this era, life was largely single During this era, life was largely single celled, and prokaryotic.celled, and prokaryotic.

Other ErasOther ErasFollowing the Following the Precambrian Precambrian era came the era came the Paleozoic,Paleozoic, MesozoicMesozoic, & , & CenozoicCenozoic eras eras

Cambrian ExplosionCambrian Explosion

• At the beginning of At the beginning of the the PaleozoicPaleozoic era, era, came the came the development of development of multicellularity. With multicellularity. With this came an this came an explosion of diverse explosion of diverse life forms, only a few life forms, only a few lines of these lines of these organisms would organisms would survive…survive…

Cambrian speciesCambrian species

TrilobiteTrilobite

AnimaloracisAnimaloracis

Cambrian Organisms contdCambrian Organisms contd..

SidneyiaSidneyiaOpabiniaOpabinia

Our Distant AncestorOur Distant Ancestor• PikaiaPikaia, was the first animal known to , was the first animal known to

posess a notochord, and is probably the posess a notochord, and is probably the ancestor to all vertebrates.ancestor to all vertebrates.

PikaiaPikaia

OrdovichianOrdovichian

The Giant OrthoconeThe Giant Orthocone

Sea ScorpionsSea Scorpions

A Canadian TimelineA Canadian Timeline

• The following scenes represent the The following scenes represent the same location of northern Canada, same location of northern Canada, separated only in time.separated only in time.

Devonian period - 360 million Devonian period - 360 million yearsyears

DunkleosteusDunkleosteus

Permian period - 280 million yearsPermian period - 280 million years

Jurassic period - 180 million yearsJurassic period - 180 million years

LipleurodonLipleurodon

CymbospondylusCymbospondylus

Jurassic period - 140 million yearsJurassic period - 140 million years

Cretaceous period - 107 million Cretaceous period - 107 million yearsyears

Cretaceous period - 75 million Cretaceous period - 75 million yearsyears

Cretaceous period 72 million Cretaceous period 72 million yearsyears

A VERY Bad DayA VERY Bad Day

Another artist’s rendition of impactAnother artist’s rendition of impact

The SurvivorsThe Survivors

Some early mammals survived the cataclysm.Some early mammals survived the cataclysm.These would be the ancestors to all living mammals.These would be the ancestors to all living mammals.Mammals weren't the only survivors, there was of Mammals weren't the only survivors, there was of course….course….

TROGDOR!TROGDOR!The BurninatorThe Burninator

Eocene period - 50 million yearsEocene period - 50 million years

Eocene period - 50 million yearsEocene period - 50 million years

Oligocene - 32 million yearsOligocene - 32 million years

Miocene - 10 million yearsMiocene - 10 million years

Pleistocene - 19,000 years agoPleistocene - 19,000 years ago