Why do dolphins jump in the air?

There's lots of debate about why dolphins jump out of the water, but we know at least one of the things they do while they're up there they grab a breath of fresh air.

Like us, dolphins are mammals.

That means even though they live in the sea, they need to breathe air to survive.

When they're underwater, they hold their breath and they have some pretty impressive lungs.

One species called risso's or gray dolphins can stay down for as long as 30 minutes.

Other species have more like a ten or 15 minute limit.

Let's see how long we can hold our breath.

Ready?

I guess I'm no dolphin, so when they jump, they can take that big, deep breath.

And then they can peek at what's happening up above the water while they're there.

Another reason they jump could be for speed.

There's less resistance when you're flying through the air.

If you see a dolphin shooting up out of the water really fast and then smacking down hard, it might be trying to get rid of a whale sucker.

A type of fish that latches onto the dolphin skin to eat parasites it finds there.

That does sound irritating.

And if you're saying to yourself that if you were a dolphin, you'd leap out of the water just for the fun of it.

You might be on to something, though.

Jumping does take a lot of energy.

Scientists think dolphins sometimes do it just because they like it gives new meanin to the phrase jumping for joy.

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