Fossil 3
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Transcript of Fossil 3
12.1 The Fossil Record
KEY CONCEPT Specific environmental conditions are necessary in order for fossils to form.
12.1 The Fossil Record
Fossils can form in several ways.
• Permineralization occurs when minerals carried by water are deposited around a hard structure.
12.1 The Fossil Record
• A natural cast forms when flowing water removes all of the original tissue, leaving an impression.
12.1 The Fossil Record
• Trace fossils record the activity of an organism.
12.1 The Fossil Record
• Amber-preserved fossils are organisms that become trapped in tree resin that hardens after the tree is buried.
12.1 The Fossil Record
• Preserved remains form when an entire organism becomes encased in material such as ice.
12.1 The Fossil Record
• Specific conditions are needed for fossilization.• Only a tiny percentage of living things became fossils.