Chapter 9.3 Paleontology Flashcards
What is paleontology?
The study of animal and plant fossils
What are fossils?
The preserved remains or traces of an organism that lived in the past.
What is the fossil record?
All the fossils that have been discovered and what we have learned from them
What do fossils tell us?
- What our planet was like long ago
- How animals changed over time
- What things looked like
What do fossils not tell us?
They cannot tell us about colors, sounds and behaviors
Are fossils common?
No, they are rare. Most things never become fossils.
How do fossils form?
Most fossils form when organisms that die become burried in sediments.
What are sediments?
Small, solid pieces of material that come from rocks or organism remains
What are three ways that fossils form?
- Petrified fossils
- Molds and casts
- Preserved remains
What are petrified fosssils?
Some remains that become buried in sediments are actually changed to rock.
A petrified fossil is a fossil formed when minerals replace all or part of an organism.
What is a mold?
A mold is a type of fossil formed when a shell or other hard part of an organism dissolves, leaving an empty space in the shape of the part.
What is a cast?
A cast is a type of fossil that forms when a mold becomes filled in with minerals that then harden.
What are preserved remains?
Organisms can be preserved in substances other than sediements such as
1. Elephant-like mammoths preserved in ICE 2. Other ancient animals preserved in TAR 3. Insects that became stuck in sticky SAP hardened, forming amber
What methods are used to determine the age of a fossil?
- Relative dating
2. Radioactive dating
What is relative dating?
It is used to determine the age of a fossil by comparing its placement with that of fossils in other layers of rock.
