ERA’S 1
What was the Mesozoic ERA know as?
The age of reptiles
What was the Cenozoic ERA known as?
The age of mammals
What are fossil records?
Fossil records are something that provided history about earth different organisms changed over time.
What are some examples of trace fossils?
Examples of trace fossils include foot prints, teeth marks on bones, fossils feces, nest or burrows.
What are examples of the fossils?
Examples of fossils include Mold & Cast, Trace, True form, and Carbon film.
What kind of extinct animal ruled during the Mesozoic ERA?
Dinosaurs ruled during this time period.
What ERA are we living in?
We are living in the Cenozoic ERA.
What are two ways to enhance carbon film fossils?
Two ways to enhance carbon film fossils is pressure and heat.
Where are fossils best preserve?
Fossils are best preserved under water.
Where are most fossils found?
Most fossils are found in sediment (dirt/mud that hardens into rock.)
When does the Cenozoic ERA span from.
The Cenozoic Era snaps from 65 million year ago to now.
What percent of marine organisms went extinct during the Paleozoic ERA?
90% of marine organisms went extinct.
What do trace fossils provide clues for.
Trace fossils provide clues of knwing what activities of ancient organisms, how big the were, what they ate.
What are different ways True form fossils can be formed?
The canb be formed from being trapped in amber, tar, or frozen in ice.
How is a carbon film fossil formed?
They are formed when an organism decomposes, and thin layers of carbon are left on the rock, creating a silhouette.
What ERA did Pangea start to happen?
Why did mammals begin to appear at the end of the mesozoic ERA?
They began to appear because of the absence of reptiles.
What are index fossils?
Short lived organisms that provide reference other rocks or nearby fossils.
How are mold fossils formed?
Mold fossils are formed when the hard part of organic material ar buried in sediment, the hard parts dissolve and leave a negitve image of the fossil.
How are cast fossils formed?
cast fossils are formed as a result of a mold fossil, minerals enter the cavity and fill in the impression.
What happended at the end of the Paleozoic ERA that caused a mass extinction?
Pangea began moving and creating more land masses, making marine organisms go extinct.
What are the ERA’s listed from oldest to youngest?
Precambrian, Paleozoic, Mesozoic, Cenozoic.
How are fossils created?
When an organism dies and is buried by sediment and the minerals become replaced.
Fossils found in the ground are not usually the original bone of the animal. How are they created?
Minerals in the soil and water seep into the tiny pores and harden over time as the fossil decays/ wears away.
What is absolute dating?
An accurate way to find the age of a rock/fossil, Scientists date rocks by using Radioactive Decay.