Dinosaurs dominated for 160 million years
Think about it. If you rewind the clock 100-200 years back, dinosaurs dominated the land.
Not just for a short period of time. But they lived for over 60 million years.
Today, we unearth dinosaur fossils of unfathomable size.
The theory is that gigantism correlates with oxygen levels in the atmosphere. Higher oxygen levels meant more size and mass.
There is varying opinion on oxygen levels during the age of dinosaurs. Regardless, these reptile-like mammals grew to extraordinary size.
Ultimately, the demise of dinosaurs was a 6-mile wide asteroid known as the Cretaceous–Paleogene extinction event. Temperatures began to plummet because a dust cloud blocked the sun.