Presentation on theme: "The study of ancient life!"— Presentation transcript:
1The study of ancient life! PaleontologyThe study of ancient life!Fossil Picture Here
2Paleontology Fossils are any evidence of ancient organisms. What can we learn from them?They can help us study how evolution has created and changed life forms on Earth.They can be used to determine relative geologic ages.They tell us about ancient climates and sedimentary environmentsSedimentary environments can include lakes, rivers, beaches, deep oceans, etc.They can help determine the positions of Earth’s lithospheric plates during the geologic past.
3How is evidence of life preserved? Body fossilsTrace fossilsBody Fossil Picture HereTrace Fossil Picture Here
4Body Fossils Body fossils are any direct evidence of prehistoric life: This includes whole bodies of animals, plants, or other organismsOr any parts of bodies such as shells, bones, or teethPetrified wood picture hereShark tooth picture hereFossilized Shells picture here
5Trace FossilsTrace fossils are any indirect evidence of prehistoric life.This includes tracks, trails, burrows, boreholes, bite marks, and coprolitesTrace fossils are useful for studying the behavior of ancient organisms.
11Fossilization What is necessary to preserve a body fossil? 1.Hard parts! (bone, teeth, shell, wood)…Hard parts stand a greater chance of preservation than do soft tissues (skin and muscle) because soft parts readily decay or decompose after death.
122. Rapid burialRapid burial helps to prevent decomposition, erosion, and disarticulation (separation of the body parts or bones).Picture of disarticulation here
13Fossilization Body fossils are preserved as: Unaltered remains Calcified skeletonsMummificationFossils in amberFrozen fossilsFossils in tarAltered remainsPetrification (Replacement)Permineralization or RecrystallizationDissolutionCarbonization
14Unaltered remainsMany marine organisms build their skeletons with the mineral calcite, which is stable over geologic time.Unaltered fossil picture here
15MUMMIFICATIONAn organism may dry out so fast that their soft parts don’t have time to decayMummy picture here
16FOSSILS IN AMBERAmber is fossilized tree sap. If an insect gets caught in the sap, it may become part of the fossil.Insect in amber picture here
17FROZEN FOSSILSAnimals may get trapped in ice and preserved. Wooly mammoths have been found preserved this way.Frozen animal (wooly mammoth) picture here
18FOSSILS IN TARAnimals may have been stuck in naturally occurring pools of tar. A famous example is the La Brea tar pits in CA.Fossil in tar picture
19Altered: Petrification or Replacement This is the removal of the original skeleton material and replacement by another mineral.Example: calcite shells that are replaced with pyrite.Fossil replaced by pyrite
20Altered: Permineralization and Recrystallization This is the filling of pore spaces in porous material such as wood or bone by the precipitation of minerals from water.Example: petrified wood, or dinosaur bonesPetrified wood picture here
21Altered: DissolutionThis is the dissolving of the original skeleton, leaving a hollow impression called a mold.A cast of the object is formed when the sediment fills in the mold and becomes rock.Mold and Cast pictures
22Altered: Carbonization This is where the only compounds left of the organism is a carbon film in rock.Carbon film fossil picture here
23INDEX FOSSILSFossils of organisms that lived during a relatively short time. They help to give a relative age to rock layers.Ammonites and Trilobites are examples of index fossils.Ammonite and Trilobite fossil here
24Stratigraphic columnPicture of a real stratigraphic column, preferably with fossils labeled