Hi, you're about to get smarter in just a few minutes with Curiosity Daily from Discovery.

Time flies when you're learning super cool stuff.

I'm Nate.

And I'm Callie. If you're dropping it for the first time,

welcome to curiosity where we aim to blow your mind by helping you to grow your mind.

If you're a loyal listener, welcome back. Today you'll learn about a bacterial discovery

that challenges our understanding of how and when life formed on Earth,

the important difference between self-control and willpower, and the truth about whether or not

your dog really loves you. Without further I do, let's satisfy some curiosity.

For our first story, I want to take you back a few billion years or so. The Earth's

atmosphere was dramatically different, full of methane instead of oxygen.

And as we've talked about a million times on this show, methane is a pretty potent greenhouse

gas.

If I remember correctly, methane traps way more heat than carbon dioxide, but it also dissipates faster, right?

Right, but with all that methane trapping, all that heat, life struggled to really gain a foothold.

But then came what scientists call the great oxygenation event or the GOE.

Uh-huh, yeah, I'm assuming that's when oxygen started to replace methane as a dominant gas.

Yeah, and once the oceans in the atmosphere were flush with oxygen, the earth cooled considerably and little creatures began popping up everywhere just slooshing and

crawling their way into existence.

Okay, so why did oxygen suddenly replace methane? Where did it come from? Was it a comet?

No, not quite. Think bacteria.

Hold up. You said there was no life back then.

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