The Cenozoic Era saw the rise of mammals as the dominant land animal, replacing reptiles. Flowering plants known as angiosperms also became the dominant land plant over gymnosperms. Major geological events like mountain building, volcanism, and earthquakes occurred in western regions due to plate tectonics during this era. Mammals were better adapted than reptiles for more active lifestyles through bearing live young and maintaining steady body temperatures.

1. 13.4 Cenozoic Era: Age of
Mammals

2. mammal
• animal that bears live young and maintains a
steady body temperature

3. Angiosperm
• Flowering plant that produces seeds within a
fruit

4. Key Concept
• Plate interactions during the Cenozoic caused
many events of mountain
building, volcanism, and earthquakes in the
West

5. Key concept
• Mammals replaced reptiles as the dominant
land animals in the Cenozoic

6. Key concept
• Angiosperms- flowering plants with covered
seeds- replaced gymnosperms as the
dominant land plants.

7. Key concept
• These adaptations allow mammals to lead
more active lives than reptiles