traces or remains of living things from long ago.
dinosaur bones and footprints preserved in stone.
replace the remains of animals/plants, forming a fossil of the hard skeletal body parts.
fossils that are actual bodies or body parts of organisms.
Types of original remains
ice, amber and tar
one of the best preservers of original remains. Bodies of 10,000 year old mammoths and prehistoric rhinos with bones, muscle, skin and hair found.
a natural substance that preserves original remains which is a thick syrup like substance from trees that hardens into a resin like substance.
large pools of a thick, oily liquid where saber-toothed cats and other animals have been trapped and preserved.
where most fossils will form
a visible shape that was left after an animal or plant was buried in sediment and then decayed away.
a solid model in the shape of the organism.
the stone fossil of a tree.
sometimes when a dead plant or animal decays, part of it is left behind in a visible layer showing details that aren't visible in normal fossils.
Not part of an animal or impressions of it, but rather evidence of a animal's presence in a given location.
tiny one-celled organisms that lived in an environment without oxygen.
used to study climate patterns.
tubular sample that shows the layers of snow and ice that have built up over thousands of years. Serve as a vertical time line of part of Earth's past.
the age of an event or object in relation to other events or objects.
fossils of organisms that were common, that lived in many areas, and that existed only during specific spans of time.
a kind of sea animal that appeared 144 million years ago and went extinct 65 million years ago. (type of mollusk).
a kind of sea animal that lived between 206 million and 144 million years ago.
the actual age of an event or object.
the length of time it takes it takes for half of the atoms in a sample of a radioactive element to change from an unstable form into another form.
James Hutton's theory with the ideas that earth is an always changing place and the same forces of change at work today were at work in the past.
father of geology
geologic time scale
divides Earth's history into intervals of time defined by major events or changes on Earth.
the largest unit of time to which the geologic scale is divided. (four of these)
eons are divided into these.
each era is subdivided into a number of these.
further subdivisions of geologic time periods.
Makes up 90% of Earth's history. Includes the Hadean, Archean, and Proterozoic eons together.
name means "ancient life"
name means "middle life"
name means "recent life"
the first era of the Phanerozoic eon. All life lived in the ocean.
best known for the dinosaurs that ruled Earth. Mammals, birds, and flowering plants first appeared. Mass extinction occurred towards the end.
the most recent era. Called the Age of Mammals because it marks the time when mammals became a main category of life on Earth.