Question

When geologists refer to the "Big Five," what are they referring to?

Answer 1

When geologists refer to the Big Five, they are referring to the five different events of extinction in history. Cretaceous-Paleogene, Triassic-Jurassic, Permian-Triassic, Late Devonian and Ordovician-Silurian.

Answer 2

The five largest mass extinctions in Earth's history.

Step-by-step explanation:

The Big Five is the term used for the 5 mass extinctions that took place during the course of Earth's history.

These big five mass extinctions were :

1. End-Ordovician
2. Late Devonian
3. End-Permian
4. End-Triassic
5. End-Cretaceous

These extinctions are really significant because they impacted the population of organisms found in those specific times drastically and also led to the evolution of new species.