"That shark really whetted my appetite for something substantial."

Approximately 375 million years ago, during the late Devonian period, our ancestors—such as the tetrapod-like Tiktaalik roseae fish—first started crawling up out of the oceans to make lives for themselves on dry land. You ever wonder why they did that? Here, I'll help you figure it out.

First, think of the scariest oceanic animal that you know of. It's a shark, right?

Okay, now watch this video: