Extinction event

Oh, quick question.

In Greater Boston, who, who, whose idea was Extinction Event? I've forgotten.

Extinction Event was Alexander's.

Oh, okay.

Through and through.

I, I-

Um, I, I, I-

I have a soft spot for Extinction Event.

So this is sort of like on the side of all that, but...

Could you please tell our listeners, what is mass extinction? And are we in the six mass extinctions? Have we met the threshold now? Are we not meeting the threshold yet? How does that look like?

To qualify as a mass extinction, a lot of taxa have to disappear from the face of the planet.

So biological extinction, you can't find them anywhere.

And the threshold for that is 75%.

You need to lose 75% of the taxa.

And like you were saying, that has happened.

We've had five mass extinctions in the past.