A Rain Forest Begins With Rain, Right? Is This A Trick Question? : Krulwich Wonders... This is a "Which came first?" riddle. Not chicken vs. egg. This one is about rain forests. When rain forests begin, do they start with rain ("Yes!" say I) or trees ("No! That's ridiculous!" say I)? I should warn you: Sometimes nature has a sense of humor.
NPR logo A Rain Forest Begins With Rain, Right? Is This A Trick Question?

A Rain Forest Begins With Rain, Right? Is This A Trick Question?

Think of a rain forest — rich with trees, covered by clouds, wet all the time.

Then ask yourself, how did this rain forest get started?

I ask, because the answer is so going to surprise you. It's not what you think.

Until I saw the video you're about to see, I just figured that a rain forest starts when a place gets rainier. (Why it gets rainier, I don't know. I don't think about that.) And then — once it starts raining all the time — tropical, rain-loving trees start to grow. They grow everywhere, and make a forest.

So I figure that's the order: rain first, forest second. It's like the name. We don't call these places forest-rains; our name for them describes how they came to be.

Or so I thought.

Now watch this — from the folks at MinuteEarth, with science explainer (and animator) Henry Reich narrating:

MinuteEarth YouTube

This isn't my first "Which came first?" story. I have also tackled the granddaddy of the genre — chicken vs. egg — and I went with the chicken. Here's why.