It's the end of the world!

This morning, we were working at the main desk with Zebra. It was very quiet. Out of nowhere, we heard this loud, weird beeping. A few minutes later Zebra said, "Did you hear that weird noise?" 
Speck said, "You mean that scary beeping noise?" 
Zebra gave this weird look. "It wasn't that scary." 
Said Speck, "No, I know. I call all beeping scary. It's a joke." 

Seriously, we tend to make these kinds of faces when there are weird noises.

Zebra just sat there for a minute, staring. Finally he gave Speck a 'boy, you're dumb' kind of look.

You've all read the Zebra posts. You tell us: Who's the dumb one?