Create an Accurate Model of Geologic Time by Matching the Clues in The

Name:______Date:______Period:__

“Where In Time?”

Directions:  Create an accurate model of geologic time by matching the clues in the Clue Box on back to the Geologic Time Scale on the front of the next page.

 Before you begin you should look over all of the clues and discuss with your lab group any that seem like they belong together.

 There are exactly enough bullet points in each geologic time period to match the time (mya) and events. Use the time scale to answer the questions below with your lab partners.

Questions:

1. Why does the geologic time scale have three eras?

2. Why is the Triassic period known as the “Age of Reptiles”?

3. Why is the Devonian period known as the “Age of Fishes”?

4. How is a geologic period defined?

5. What do scientists mean by the term “Cambrian explosion”?

6. Why is the Cambrian explosion a significant event in Earth’s history?

7. What kinds of species reveal patterns of evolution within the geologic time scale?

8. Can you think of a reason why, during the Cretaceous period, Earth’s atmosphere contained about 50% more oxygen than it does today? Geologic Time Scale Era Period MYA Notes Millions of Years

 Quaternary  Cenozoic  Tertiary  

Cretaceous  

Mesozoic  Jurassic 144 

Triassic 208 

Permian  

 Paleozoic 

 Carboniferous 286 Pennsylvanian Carboniferous   Mississippian  Devonian  

Silurian 408 

Ordovician  

Cambrian 505 

 

Precambrian Early life forms on the Earth (bacteria, algae, jellyfish, corals, and clams). This era accounts for close to 88% of Earth’s history. Assessment Rubric Uses correct grammar, punctuation, and spelling. 4 Correctly matches the clue to the geologic time period. 4 Provides accurate information about the plant life of the time period. 4 Correctly identifies where the animals belong in an evolutionary pattern. 4 Includes facts from the geologic time scale for support. 4 TOTAL POSSIBLE POINTS 20

CLUE BOX During the Quaternary 144 million years ago, During the Tertiary During the Tertiary period, present day largest dinosaurs period, 1.8 million years period, the first sea homo sapiens (humans) appeared, such as ago, a continental glacier mammals, such as the began to inhabit the Stegosaurus, Diplodocus, formed over Antarctica. whale and the dolphin, Earth. and Apatosaurus. It is still there today! began to develop. Tyrannosaurus Rex During the Jurassic At the end of the The Triassic period was began to appear during period, the first flying Triassic period, Pangaea known as the “Age of the Cretaceous period, animals, such as the began splitting apart. Reptiles” because which ended around 66.4 birds and flying reptiles, reptiles such as turtles, million years ago. began to appear. crocodiles, and dinosaurs became abundant. The first mammals, The super continent There were very few During the Permian which evolved from the Pangaea formed during fossils of many land and period, the southern warm-blooded reptiles, the Permian period, sea animals, and no region of Pangaea was in began to develop in the which was 245 million fossils of dinosaurs, an ice age. Triassic period. years ago. found after the Cretaceous period. The first warm-blooded During the Sharks, fish, and We were unable to reptiles began to Carboniferous amphibians were common locate any fossils from develop around 245 Pennsylvanian period, during the many species of million years ago. the first reptiles Carboniferous invertebrates after the developed. Also, large Mississippian period, Permian period. swamp forests made of which was 320 million huge trees were years ago. abundant. During the Devonian The Devonian period, There were many plants During the Silurian period the lungfish ending at about 360 during the Cretaceous period, the first fish developed. million year ago, was period. with jaws began to known as the age of develop. fishes. Fish with scales and bony skeletons developed during this time period. Around 438 million years During the Ordovician During the Cambrian period, During the Precambrian ago, the first fish began period, the first fish, there were large amounts of period, oxygen began trilobites, brachiopods, developing in the sea. which were jawless, sponges, and other sea building up in the These fish were jawless. began to develop. invertebrates. atmosphere.