Question | Answer |
Fossils | the remains or traces of a once-living organism |
Mold Fossil | a cavity in a rock that has the shape of the organism that was trapped there |
Cast Fossil | a type of fossil formed when an earlier fossil in rock is dissolved away leaving behind the ijpression of that fossil and new sediment or minerals enter and fill in the mold |
Petrified Remains | plant or animal remains that have been petrified or "turned to rock" when minerals soak in, replace the remains, and harden |
Preserved Fossil | a fossil that forms when the organisms or parts of organisms are trapped in ice, tar, or amber and are prevented from decaying |
Carbonized Fossil | a fossil impression ina rock, consisting only of a thin carbon deposit |
Trace Fossil | fossilized tracks and other evidence of animal activity |
Adaptation | a tra1t that helps an organism to survive and reproduce |
Variations | Differences within species based on traits |
Species | a group of organisms that have similar charcteristics to each other and that typically reproduce only with each other |
Natural Selection | the process by which some organisms survive and reproduce because they have traits favorable to survival in an environment, while others die out because they lack those traits |
Index Fossil | Used to date other fossils: Lived a short period of time, geographically widespread and very abundant. |
paleontologist | a person who studies fossils |
Sedimentary Rock | usually found in layers and contains fossils |
Theory | an educated guess based on research and observations |
amber fossil | formed from harden tree sap/often engulfs and preserves entire organisms |