Why are mass extinction extremely rare?

Answer 1

That's a tough questions because there are many answers to it.

Most rocks are meteors which burns before hitting the earth. There are much fewer meteorites that hits earth before completely burned than meteors but most meteors aren't large enough to wipe out life. There are much fewer dangerous meteorites that could wipe out life on earth than normal meteorites. Fortunately, most dangerous meteorites are very far away from the earth. All the gas giants and black holes draws in most of the dangerous asteroids that could wipe out life. There are much fewer dangerous asteroid that comes near earth than dangerous asteroid that got defeated but most dangerous asteroid that comes near earth won't hit earth and just pass by. There are much fewer dangerous asteroids that hits earth than the dangerous asteroid that pass comes near earth. The dangerous asteroid that hit earth could trigger a mass extinction. Most mass extinctions causes most of the life to be wiped out. Only a very few mass extinctions causes completely all of the life to be wiped out.

Mass extinctions only happen a very few time every millions of years, which means after a mass extinction occurs, there won't be another mass extinction for millions of years later. That's why mass extinctions are extremely rare.

Frequency Arrangement:

Meteors, Meteorites, Dangerous Meteorites (sucked in by gas giants and black holes), Dangerous Meteorites (Come pass by earth), Dangerous Meteorites (Wipes out most life), Dangerous Meteorites (Wipes out completely all life)

There have been 5 mass extinctions in the past which is 443.8 million years ago (Ordovician-Silurian), 377.5 million years ago (Late Devonian), 252 million years ago (Permian-Triassic), 201.3 million years ago (Triassic-Jurassic) and 66 million years ago (Cretaceous-Paleogene).

Most scientists predicted it's most likely that there will be no more mass extinction in the future.

Life will be extinct 5.4 billion years ago when the sun expands into red giant because the expansion of the red giant sun causes the earth's ocean to evaporate, making it uninhabitable for life.