1. Mesozoic Era (Age of the Dinosaurs)
225,000,000 years ago to 65,000,000 years ago
Warm Climate
Three Periods
Triassic
Jurassic
Cretaceous

3. Mesozoic Era Triassic Period (225-180 MYA)
Pangaea (supercontinent) formed

4. Mesozoic Era Triassic Period (225-180 MYA)
First Dinosaurs (small in size)

5. Mesozoic Era Triassic Period (225-180 MYA)
Conifers and Cycad Forests Dominate (Gymnosperms)

6. Mesozoic Era Jurassic Period (180-135 MYA)
Pangaea starts to separate

7. Mesozoic Era Jurassic Period (180-135 MYA)
Dinosaurs Dominate: Allosaurus, Diplodocus, Brachiosaurus, Stegasaurus.

8. Mesozoic Era Jurassic Period (180-135 MYA)
1st mammals (small rodents).

9. Mesozoic Era Cretaceous Period (135-65 MYA)
Continents in modern positions

10. Mesozoic Era Cretaceous Period (135-65 MYA)
Flower plants (angiosperms) evolve & dominate

11. Mesozoic Era Cretaceous Period (135-65 MYA)
Mass Extinction: 50% of all plant and animal groups die out
Alvarez’s Meteor Impact Theory- iridium layer (common in meteors), dust blocked out the sun.

12. Cenozoic Era (Age of the Mammals)
65,000,000 years ago to Present Day
Two Periods
Tertiary
Quaternary

14. Cenozoic Era Tertiary Period (65 MYA to 1.8 MYA)
Warm and humid climate
Mammals dominate: increasing in size
Earliest prehistoric humans (approx. 4 MYA).
Flowering plants (angiosperms) dominate
Grasses develop, grazing animals become even larger

15. The Great Ice Age

16. Cenozoic Era Quaternary Period (1.8 MYA to Present)
The “Great Ice Age”, ice sheets covered 30% of all land
Land & ice bridges connected many continents allowing animal migration
North American elephants (mastodons, mammoths), giant sloths & armadillos, and saber-toothed cats go extinct.
Modern humans evolve, maybe causing the above extinctions from over hunting.