Cenozoic

Definition

The Cenozoic is the most recent geological era, spanning from approximately 66 million years ago to the present. This era is characterized by significant changes in climate, biodiversity, and the evolution of mammals and birds, following the mass extinction event that marked the end of the Mesozoic Era. The Cenozoic is crucial for understanding the development of modern ecosystems and how organisms adapted to changing environments.

5 Must Know Facts For Your Next Test

1. The Cenozoic Era is often referred to as the 'Age of Mammals' due to the dominance of mammals in various ecosystems after the extinction of dinosaurs.
2. This era is divided into three main periods: Paleogene, Neogene, and Quaternary, each showcasing distinct evolutionary trends and climatic shifts.
3. During the Cenozoic, there was a significant cooling trend, leading to ice ages that shaped global climate patterns and influenced species distribution.
4. The emergence and evolution of flowering plants during the Cenozoic provided new habitats and food sources for many animal species.
5. The Cenozoic has seen major geological events, including mountain building and plate tectonics that have shaped continents and ocean basins.

Review Questions

• How did the climate changes during the Cenozoic affect biodiversity?
  • Climate changes during the Cenozoic had a profound impact on biodiversity by influencing habitat availability and species interactions. As temperatures fluctuated and ice ages occurred, many species adapted to new environments or faced extinction. The diversification of mammals and birds during this era was closely linked to these climatic shifts, as new ecological niches opened up and different survival strategies emerged.
• Evaluate the significance of flowering plants in shaping ecosystems during the Cenozoic Era.
  • Flowering plants played a critical role in shaping ecosystems during the Cenozoic Era by providing diverse habitats and food sources. Their evolution allowed for more complex food webs and facilitated interactions between various species. This increased plant diversity supported herbivores, which in turn influenced predator populations, creating a dynamic balance within ecosystems that set the stage for modern biological communities.
• Analyze how geological events during the Cenozoic influenced the evolutionary trajectory of mammals.
  • Geological events during the Cenozoic, such as continental drift and mountain building, significantly influenced mammalian evolution by altering habitats and climate. For example, as landmasses shifted, new barriers were formed, leading to isolation of populations and subsequent speciation. The formation of mountain ranges also affected climate patterns, which created different ecological zones that drove adaptation in mammals. These factors contributed to the incredible diversity seen in mammal species today.

Related terms

Paleogene:

The Paleogene is the first period of the Cenozoic Era, lasting from about 66 to 23 million years ago, marked by the diversification of mammals and birds after the extinction of dinosaurs.

Neogene: The Neogene is the second period of the Cenozoic Era, spanning from about 23 to 2.6 million years ago, characterized by further evolution of mammals and birds and significant geological changes.

Quaternary:

The Quaternary is the most recent period of the Cenozoic, beginning around 2.6 million years ago and continuing to the present, known for its ice ages and the rise of humans.