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remains/imprints of prehistoric life


study of fossils, ancient life forms,

Hard parts

parts of the organism most likely to become a fossil (bones, teeth, shells)

Sedimentary Rocks

only rocks to contain fossils


fossilized waste


dinosaur stomach stones


imprint in rock or sediment


results when sediment fills in mold


earliest known fossils

Index fossils

used to estimate age of rocks


common index fossil


insects, spiders, scorpions, etc.


extinct marine arthropods (sea scorpions)

Original remains

can be preserved by ice, amber, or tar.

Trace fossil

imprints, trails, or burrows

Carbon Films

imprint of plant/ insect on shale

Petrified Wood

forms when silicarich wood turns into rock

Relative age

"oldest rock layer is on bottom"

Absolute Age

exact age of rock layer in years

Mass extinction

seperates geologic eras


the age of marine invertebres (all life in the ocean)

Cambrian Explosion

sudden appearence of diverse life

Silurian Period

the Age of corals (first plants and animals on land)

Devonian Period

the Age of fishes (first amphibians)

Carboniferous Period

the Age of coal (first reptiles)

Permian Period

the Age of amphibians and reptiles )largest mass extinsion in earths history)

Triassic Period

first dinosaurs (pangea starts to break up)

Jurassic Period

the Age of dinosaurs (first mammals, first birds)

Cretaceous Period

named after chalk (first flowering plants)

Tertiary Period

the age of mammals

Quaternary Period

the Age of humans (mega mammals die)

Pleistocene Epoch

mega mammals die off at the end of the pleistocene epoch

Holocene Epoch

today epoch

Dinosaur Foot Shape

first or original classification

Dinosaur Hip Shape

todays classification


5 toed meat eaters


large plant eaters, large necks, large tail


horned dinosaurs

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