Chapter 15 Section 4 January 3, 2011  Focus: Anticipation/Reaction Guide  ( See following slide)  Put responses in CPS  Notes:  What are fossils? Describe five ways to become a fossil and describe each  Name three additional fossil and describe  How are fossils used to trace the past?  How are fossils used to date rock?  Why are ammonites and trilobites index fossils?

How do we date rocks and fossils? Relative DatingAbsolute Dating-  The process of getting the age of an object by determining the number of years it has existed. 72/lectures/week01/img010.gif

Anticipation/Reaction Guide Statements Respond to the statements in your journal. Record whether you agree or disagree with the eight statements mentioned below. Write your responses in your journal.  Fossils are only preserved in rocks.  Freezing of an organism often keeps it preserved in its original state.  Although tracks provide evidence of animal activity, they do not reveal much about the animal that made them.  A mold and a cast are the same thing.  Fossil records give scientists an extra history of life on Earth.  Scientists can learn about changes in the climate just from fossil records.  Only a small fraction of the organisms that have existed in Earth's history have been fossilized.  To be considered an index fossil, it must be found in rock layers worldwide.

Fossils How do fossils form? Read p In rocksIn Amber PetrifactionIn asphalt Frozen

Fossils – 5 types amber frozen rock petrifacation asphalt

Fossils  the remains or physical evidence of an organism preserved by geological processes

Fossils  Paleontologists study fossils  Fossils are the remains of organisms preserved by geologic processes…. These are used to date the age of the rock _mammoth_fossils_1_640x480.jpg es/Fossils.jpg

Ways to preserve organisms  they are buried quickly to avoid decay  they have hard parts that don’t decay easily

Original remains of organisms can be preserved in  Amber  Asphalt or tar pits  ice  Petrifaction

A mber fossils can be preserved in amber (hardened tree sap) ex. Insects fossils, frogs, lizards /webpictures/insectinamber.jpg files/p_ribnitiodamgartensis(fossil).jpg

Mosquito in amber sc_05_img0260.jpg gallery/amber_zoom.jpg

Fossils in Rock  When an organism dies, it begins to decay or get eaten!  Organisms get buried into sediment and hard parts become resistant to decay.  Hard parts preserved but soft tissue decay.

Fossils can be preserved in asphalt or tar pits err/fossil/mammal/6mammoth- tar-pits1957.jpg La Brea asphalt in California)

Frozen fossils AMMOTH.gif ice (wooly mammoth) Cold temperatures slow down decay. Frozen fossils are preserved from last ice age. Subfrezzing climates contain no decomposing bacteria.

Permineralization Petrifaction – minerals replace original tissue rmineralization560.jpeg yard.org/images/ty/petwooda.jpg

Forms of petrifaction  Permineralization– a process in which minerals replace an organisms hared tissues (petrified wood) or bone  Replacement- organisms tissue is completely replaced by minerals. ( all wood replaced)

February 4, 2015  Focus: Write a paragraph to describe the fossils record of your own lives that might be found 65 million years from now.

Fossils How do fossils form? Read p In rocksIn Amber PetrifactionIn asphalt Frozen

Fossils – 5 types amber frozen rock petrifaction asphalt

What clues do organisms leave behind for paleontologist? Fossil Evidence Trace Fossils Mold Cast

What clues of organisms are left for paleontologist to interpret the past?

How are fossils used to date rocks?

Trace fossils are any naturally preserved evidence of animal activity (footprints, tracks) pg&imgrefurl= 1Lm0K5SBqJDdueg=&h=313&w=315&sz=34&hl=en&start=14&sig2=r764v9sIscXyIQYhINDK4g &itbs=1&tbnid=QuT1qCnHwgBdiM:&tbnh=116&tbnw=117&prev=/images%3Fq%3Dpermineraliz ed%2Bfossils%26gbv%3D2%26hl%3Den&ei=ZrgqS6_FFJXj8Qa_9qmeBw tell how big organisms are, how fast they move, or if they travel in groups.

Trace fossils Examples: burrows-made when filled in with sediment and buried quickly. ( clams) Coprolite- fossil in animal dung.  tracks dung - corprolite burrows

mold  a mark or cavity made in sedimentary rock by a shell or other body that was buried c/wood1.jpg&imgrefurl= s.html&usg=__2UelulY5N5wH1Lm0K5SBqJDdueg=&h=313&w=315&sz=34&hl=e n&start=14&sig2=r764v9sIscXyIQYhINDK4g&itbs=1&tbnid=QuT1qCnHwgBdiM:& tbnh=116&tbnw=117&prev=/images%3Fq%3Dpermineralized%2Bfossils%26gbv %3D2%26hl%3Den&ei=ZrgqS6_FFJXj8Qa_9qmeBw

mold stMold560.jpeg erck/nature/specimens/image s/intmold22403.s.jpg

cast  a type of fossil that forms when sediments fill in the mold cavity left by a decomposed organism and becomes a rock.  Shows what the outside of the animal looked like. fossils.jpg

cast mages/Carbonization2.jpg _eff7cb4d45.jpg?v=0

Carbon film users/pciesiel/gly3603c/fossils.html&usg=__2UelulY5N5wH1Lm0K5SBqJDdueg=&h=3 13&w=315&sz=34&hl=en&start=14&sig2=r764v9sIscXyIQYhINDK4g&itbs=1&tbnid=Q uT1qCnHwgBdiM:&tbnh=116&tbnw=117&prev=/images%3Fq%3Dpermineralized%2B fossils%26gbv%3D2%26hl%3Den&ei=ZrgqS6_FFJXj8Qa_9qmeBw

Fossil Record  The fossil record is incomplete because most organisms never became fossils or have yet to be discovered.  Reveal evidence of environmental changes and how organisms changed over time. How are fossils used to interpret the past?

index fossil  a fossil found in the rock layers of only one geologic age. These are used to establish the age of rock layers Examples: Trilobite Ammonite How are fossils used to date rocks?

Gastropod and Trilobite g.jpg guidebooks/NEKS/figs/trip21.jpg

Ammonite _fossils.jpg ammonite.jpg

Fossilized leaf rthspace/images/show2_fossil1.jpg

What clues do organisms leave behind for paleontologist? Fossil Evidence Trace Fossils Mold Cast

Directions: Put the events below in the right sequence using the lines provided. 1. The sediment is squeezed and cemented together into rock. 2. The seashell becomes buried in sediment. 3. Other sediments fill the hollow place and harden into rock. 4. A seashell falls into the mud. 5. Someone finds the fossil of a seashell buried in sediment and rock. 6. Holes in the rock let water and air reach the seashell and dissolve it/ leaving behind a hollow place in the rock. January 5, 2011 Sequence Activity

January 5, 2011 Geologic Time Scale p  How long have geologist studied Earth’s history?  Name the sections of time Earth’ history has been divided into from largest to smallest.  What do the boundaries between geologic time intervals represent?  What is extinction?  Explain the causes of mass extinction. What was it due to?  Define Glaciation  Why do scientist use ice cores?  Explain the events of the Paleozic Era, Mesozoic Era, and Cenozoic Era. You may use a tree map to organize your information.

February 4, 2015  Come in the class,sit quietly, and get your notebook out!  Label your notes: Geologic Time Scale  1) AGENDA: TAKE NOTES 2)GUEST SPEAKER: DR.FOSSIL

Fossil Dig  Separate fossils  Label Fossils on the paper towel THINK ABOUT IT !  What types of organism formed from these fossils?  Where in the world could you find these fossils?

Geologic Time Scale  Homework:  How do Fossils Form?  Geologic Periods/Fossils Worksheet  Study for your chapter 15 test Monday

Geologic time covers 4.6 billion years One of the best places to study earth history is the Grand Canyon

Geologic time scale  How scientists divide the age of the earth. Eon Era Period Epoch

Division of Geologic Time  Eon largest Hadean, Archean, Proterozoic, Phanerozoic  Era second largest contains two or more periods Paleozoic, mesozoic, cenozoic  Period third largest periods are divided into epochs  Epoch smallest

Boundary lines  Boundaries between geologic time intervals represent shorter intervals in which visible changes took place.  Some changes marked by disappearance of index fossils

extinction  They all died out!

Climate change and Extinction  Changes in Earth climate disrupt the environment and cause  global cooling or glaciation  Global cooling is caused by airbourne ash from volcanic eruptions or debris thrown into the atmosphere by asteriods  Glaciation is large amounts of water frozen in ice sheets during global cooling.

Ice Cores  Cylinders of ice drilled to obtain information about trapped atmospheric gases and particles (dust, soot, volcanic ash, chemical compounds) to show atmosphere composition of the past. Cores/Images/greenland_drilling.jpg

Phanerozoic Eon  Means “visible life”  Consist of  Paleozoic era  Mesozoic era  Cenozoic era

Paleozoic Era  Means “Old life”  First represented by fossils  Lasted from Million years ago  Marine life flourished at the beginning  Land plants appeared in the middle  Amphibians and reptiles live on land at the end  Insects were abundant  Largest Mass extinction which may be due to changes in seawater circulation.

Mesozoic Era  Means “Age of the Reptile”  Began 248 million years ago  Reptiles inhabited and dominated land  Small mammals appeared and  Dinosaurs and bird appeared late in the Mesozoic era  Dinosaurs and % of the species became extinct at the end of the era  Extinction may be due to global climate change.

Cenozoic Era  Means the “age of the mammal”  Began 65 million years ago and continues to present day  Mammals had to compete with dinosaurs and other animals for food.  Mammals can regulate body temperature internally and ablity to bear young inside mothers were unique traits.  We are here!!!!!!!

January 7, 2011  Focus:  Name the Epoch, Period, Era and Eon we live in.  Bill Nye DVD: Fossils  Excavate the Pterosaur  Chapter 15 Test Monday !!!!!!!!!!!!!!!

Answer  Phanerozoic Eon, Cenozoic Era, Quartnernary Period, and Holocence Epoch

January 10, 2011  Focus: Study for the Chapter 15 Test  Pick up your CPS remote  Finish the Pterosaur Lab Cut out and questions  Read Chapter 16 Section 1 and 2  p. 470 – 477 Take notes in your own words