Life began in the water.

It looked across the boundary between wet and dry, and saw... dinner.

Some species evolved legs from their fins and became land animals.

Others, like this archerfish, found a way to bridge the distance between water and land... while still staying wet.

Archerfish spit water in a high-pressure stream through the air, knocking prey from its perch.

Pretty clever, right?

They live in the estuaries of Southeast Asia, where mangrove trees stand knee deep in brackish water.

It's the perfect arena for a deadly game of hide and seek.

But this fish has more than just good aim.

Depending on the distance to its target, the archerfish can calibrate, changing the shape and speed of its spit.

A series of experiments at Wake Forest University measured the force of that spit on impact.

The spitball on the left has further to go, but it still packs the same punch.

That's because its tail end catches up to the front on contact.

Like an archer pulling a bowstring, the fish judges the distance, makes a few calculations, then lets it fly.

You might say it's using water as a weapon.

But wait a minute... That kind of sounds like tool use, which among scientists who study evolution is a big deal.

Because we used to think that you needed a big, complicated brain -- more like a human brain -- to use tools.

And like all fish, this archer has no neocortex, that outer layer of the brain, where functions like higher reasoning and memory live.

In other words, this fish has less of a brain than we do, but in a way, it's incredibly smart.

But how smart?

That's what one Oxford scientist wanted to know.

She asked: Can an archerfish tell one human face from another?

In her lab, she trained an archerfish to expect food whenever it spat at the image of this one face.

See, facial recognition is another of those abilities you're supposed to need a neocortex for.

When she showed the fish a series of other faces...Nothing.

But when that familiar face appeared?

Bingo.

In spite of its tiny brain, it knew the face.

We humans have used our brains as the baseline for intelligence -- if you don't have our hardware, you can't do what we can do.

But that idea is evolving.

The archerfish and many other animals... it turns out, have found their own ways to be smart.

Are you a better shot than an archerfish?

Try hitting a beer bottle with a snowball from about 50 feet away and you'll see.

And check out this episode about some other animals that manipulate water to survive.

They carry a breathing bubble around with them, like little scuba divers.

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