Understanding What a Geological Era Is
A geological era is a major division of Earth’s history. Eras divide long stretches of time based on big changes in climate, life, and the planet’s surface.
How Scientists Define Eras
Geologists study rocks, fossils, and sediment layers to identify major shifts. When many species appear or disappear, it marks the boundary between eras.
The Main Geological Eras
Paleozoic Era: Ancient oceans, early plants, and the first land animals.
Mesozoic Era: The age of dinosaurs, lush forests, and early birds.
Cenozoic Era: The age of mammals, modern climates, and eventually humans.
Why Geological Eras Matter
Each era reflects major events like mass extinctions, climate shifts, and new forms of life. They help scientists understand how Earth has changed through time.
How Eras Fit Into Geological Time
Eras are part of the geological time scale, which also includes smaller divisions like periods and epochs. Together, they form Earth’s historical timeline.
The Simple Takeaway
A geological era is a large time division marked by major changes in life and Earth’s environment. It helps us understand the planet’s long and complex history.