| A | B |
|---|
| fossils | preserved remains or traces of living things |
| What do fossils provide to scientists? | how life has changed over time and how Earth's surface has changed |
| HOw do fossils form | living things die and are buried by sediments that harden into rock and preserve the shapes of the organisms |
| paleontologists | scientists who study fossils |
| Where are fossils usually found | sedimentary rock |
| what is sedimentary rock | the typr of rock that is made of hardened sediment |
| Where do fossils usually form | plants or animals that once lived near quiet water |
| What part of the animal is fossilized | the hard part because the soft part decays quickly or is eaten by animals |
| What are some examples that turn into fossils | bones, teeth, shells, seeds and woody stems |
| What are the processes that a fossil may form in rock | petrified fossils, molds & casts, carbon films and trace fossils |
| How are organisms preserved in substances | tar, amber or ice |
| petrified fossils | fossils in which minerals replace all or part of an organisim |
| what does petrified mean | turning into stone |
| What are the steps of petrified wood | water rich in minerals seeped into the spaces, the water evaporated leaving the hardened minerals |
| What is another way petrifed fossils may form | replacement |
| what is replacement | the minerals in water make a copy of the organism |
| what is mold | a hallow area in sediment in the shape of an organism or part of an organism |
| when does mold form | the hard part of the organism,like a shell, is buried in sediment |
| cast | a copy of the shape of the organism |
| how is cast different than mold | the water deposits the minerals and sediment into the empty space of a mold |
| carbon film | an extremly thin coating of carbon on rock |
| How does carbon film form | sediment buries the organism, materials that make up the organism become gases, these gases escape from the sediment |
| what does carbon filming preserve | the delicate parts of plant leaves and insects |
| trace fossils | provide evidence of the activities of ancient organisms |
| what is an example of trace fossils | fossilzed footprints |
| what do most types of fossils preserve | the shapes of ancient animals and plants |
| What do fossilized footprints tell scientists | clues about the animals size, behavior, speed # of legs it walked on, did it live alone |
| What is another use of trace fossils | clues about the size and shape of the organism, where it lived and how it obtained food |
| What are 3 ways remains are preserved | tar, amber and freezing |
| how does tar preserve organisms | soaks into their bones |
| how does amber preserve the organism | the insect becomes trapped in the resin, or sap, the insect dies and more resin covers it |
| fossil record | provides evidence about the history of life on Earth |
| what else does a fossil record show | different grous of organisms have changed over time |
| what is the surprising fossil record fact | fossils occur in a particular order |
| what did older rocks tell scientists | simpler organisms |
| what did younger rocks tell them | complex organisms |
| scientific theory | well-tested concepts that explain a wide range of observations |
| evolution | the gradual change in living things over long periods of time |
| what did the fossil records show | millions of types of organisms have evolved |
| extinct | organisms that no longer exists and will never again live on Earth |
| how do fossils tell about the Earth's environment | fossils tell whether the area was a shallow bay, an ocean bottom or fresh water swamp |
| how do fossils tell about the climate | coal found in Antartica shows it was once was warm and swampy |
| how do fossils tell about Earth's surface | corals live in warm, shallow seas and some were found in midwestern US |
