Doom of the Dinosaurs
Unfortunately, this massive extinction of life was not an isolated event. Over the past 500 million years, the Earth has experienced five large scale extinctions. One of them was so complete in its utter devastation it is estimated only 4% of life on Earth survived.
These moments of “great dying” have drastically impacted the biological and evolutionary trajectory of life on Earth. For the most part, the reasons for these extinctions remain shrouded in mystery though evidence of global cooling, severe volcanic upheaval, and even extrasolar events like Gamma Ray Bursts remain likely causes.