Hey, recording.

Yeah.

You did it.

(Hanson) This is my friend, Dianna.

You probably know her from "Physics Girl."

How's it going?

I needed to show you something because I'm not a physicist.

I don't know physics like you do.

Okay, that's what I'm here for.

I'm about to show her one of the fastest animals in nature.

You might be picturing something like this: Or this: Or even this: But you'd be wrong.

The actual fastest animals on earth can accelerate from zero to 200 miles per hour 5,000 times faster than the blink of an eye.

They can pull enough G's to turn your body into Jell-O.

And they could hang out on your fingertip.

(Cowern) Whoa.

(Hanson) Boing.

(Cowern) [laughs] Oh, my God.

What is it even doing?

Oh, my gosh, you silly bug.

(Hanson) These tiny animals can store and release energy in some mind blowing ways, even better than some of our most advanced inventions.

And today, using some super-slow motion macro video and a little physics, we're going to answer this question: How fast are the fastest animals?

And how do they do it?

[light instrumental music] Hey, smart people.

Joe here.

So humans have reached some pretty impressive speeds.

Of course, there are different ways to go fast.

One option is you can speed up very slowly for a long time, like NASA's Dawn Spacecraft.

Its ion thrusters put out less force than it takes to push a single key on a keyboard.

But it accelerated to over 11 kilometers per second by firing that tiny engine for nearly six years.

But the real challenge is getting going fast quickly.

And that's where teeny, tiny bugs leave us humans in the dust, along with pretty much every other large animal on earth.

This awesome footage was captured by Adrian Smith, a biologist who developed a bit of an obsession with studying nature's tiny speed freaks.

And thanks to his YouTube channel, so have I.

But before we go any farther, let's get back to our friend Dianna so she can explain the unique physics problem that these tiny, little insects have solved.

So we're talking about little bugs jumping fast.

Velocity is just, like, how fast you're going in what direction.

Acceleration is changing your speed or the direction that you're going.

And that's where you got to put in effort.

I have to put in some energy in order to change my velocity.

Now imagine you wanted to change the speed really fast.

The thing is, things just want to stay going the way they're going in the same speed, or they want to stay not moving if they're not moving.

Things resist changes in motion.

They have inertia.

As you may know-- (Speaker) Inertia is a property of matter.

The last piece of analyzing a change in speed is to think about mass.

And to think about the fact that if I want to push something up to speed, like, pushing a real big human up to a certain speed takes a lot of effort.

But pushing a small, little human up to speed doesn't take nearly as much effort.

Pushing a tiny--a tiny, little being up to speed, I would just have to flick it.

So, you want to flick tiny, tiny beings for science?

Don't flick tiny, tiny beings.

So there's an equation that describes the relationship Dianna's talking about-- the equation for kinetic energy.

Energy is on the left.

And on the right side we have an "m" in there for mass.

Which means that if we have a bigger mass, then the energy we have to put in to move increases at the same rate.

It's a linear relationship.

And that means if we have a smaller mass, then it takes less energy to move.

And having a tiny, tiny mass is what lets those bugs that we saw accelerate faster than just about any other animals on earth.

But studying how they do that isn't easy because, well, first you've got to catch them.

Or Adrian does, anyway.

(Smith) So recently, I was surprised when a bunch of really cool bugs showed up right outside my door.

These are springtails on the lid of my trash can.

Springtails are tiny soil arthropods that launch themselves into the air to avoid predators.

Or in this case, my finger.

Springtail jumping hasn't been studied much.

So I collected those and brought them back here, to the lab, to film them with this high speed camera.

Filming them is a challenge.

These springtails are tiny, so the best way to handle them is to push them around with a tiny paintbrush.

Then the challenge is to follow them around with a camera and hope they jump while you've got them both in frame and in focus.

When I did manage to catch them on film, what I saw was astounding.

(Hanson) These springtails go really fast, really quickly.

Clocking an upwards acceleration of 700 meters per second squared in a fraction of a second.

Which is almost 20 times the acceleration of a top-fueled dragster.

And about 100 times quicker than an accelerating cheetah.

Fastest animal on earth?

I don't think so, kitty.

To do what these bugs do, even with their tiny mass, they have to store and release a ton of energy all at once.

Enough energy to send a springtail spinning at 374 flips per second.

That's almost 40 times faster than a spinning helicopter rotor.

But when scientists crunched the numbers, they uncovered a mystery because muscles alone are incapable of producing that much energy in such a short amount of time.

What they're doing seems beyond the physical limitations of biology itself.

Muscle tissue can only contract so fast, which means it can only provide a finite amount of energy to accelerate.

That's why humans can't throw a 1,000 mile per hour fastball.

These bugs must be releasing that energy using something other than muscle power alone.

The answer?

Well, it's right in the name.

They use springs.

What is a spring?

So a spring is this mechanical device that stores some energy to be released later, usually very quickly.

'Cause the idea of springs is that you usually put in energy over a longer amount of time.

Like, you incrementally compress it or stretch it and then it snaps back really fast.

The wound, tight coil of wire-- get down into the microscopic level and you've got bonds between all of these atoms and molecules, and you're stretching those apart.

So when you release the spring, those molecules and atoms all snap back into place and you get this release of energy, and typically you push or you pull something really fast.

So actually, a spring is often made of little, mini springs.

Like, all the atoms and molecules act like springs themselves.

So the main idea with a spring is you can slowly store energy using a small amount of force over a longer time.

And then release that energy very quickly to do a lot of work.

Only instead of atoms in a metal being stretched like in a traditional spring, these insects and other superfast creatures with exoskeletons like the mantis shrimp, well, they store and release energy using their exoskeletons.

And those exoskeletons are made of flexible and stiff materials mixed together.

That's called a composite material, and engineers use them all the time.

A springtail's launching appendage is part of its exoskeleton.

And it stores energy just like the spring on a mouse trap.

It stays locked and loaded until... What's crazy is springtails aren't even close to the bug acceleration record.

These are froghoppers.

Little insects that you might find sucking juices out of plants.

And in addition to looking very weird and cool, they're among the fastest jumping insects ever recorded.

The fastest froghoppers can accelerate at 5,400 meters per second squared.

That's just under 550 G's.

Froghoppers, and their cousins, the planthoppers and leafhoppers, they do this using an incredibly cool, simple machine that is built into their bodies.

They draw up their hind jumping legs.

They lock them in place with an actual latch that sticks out of their belly.

They flex a big muscle to bend their exoskeleton.

And then open that latch to release the energy all at once.

It's almost the same way that a crossbow or a catapult works.

Only here, they're using their flexible but strong exoskeleton as the spring.

Now, I'm not an engineer but the fact that they have simple machines, latches, and levers and springs built into their bodies, that blows me away.

But they aren't the fastest either.

These are trap-jaw ants.

And it's not their whole bodies that move fast.

They can snap their jaws shut in less than 1/1000th of a second.

Which is an acceleration of around 100,000 G's.

That's more than the acceleration of a bullet leaving a gun.

And they do it by using their entire head as a spring.

So even though these ants are accelerating their jaws really quickly, the force they're generating on impact is tiny relative to us.

That's because their jaws don't have that much mass.

Basically, when this ant snaps against the tip of my finger, I can barely feel it.

But organisms, like these ants, have evolved to meet challenges on their own physical scale.

The jaws of this ant have evolved ultrafast acceleration to catch prey.

And the forces they generate might not seem like much to us, but to the ant, it's enough for them to do incredible things.

Like this one using its jaw snap to escape from a pit of an antlion.

By timing those snaps perfectly, trap-jaw ants can catapult themselves more than 40 centimeters away, which is like me flinging myself back by like 100 feet.

That ant was the animal acceleration record holder until 2018 when it was dethroned by the snap-jaw or Dracula ant, which snaps its jaws in 23 microseconds.

That's millionths of a second.

20 times faster than the trap-jaw ant.

Those mandibles go from 0 to 200 miles per hour in .000015 seconds.

And it's hard to believe, but that snap-jaw was just knocked out of first place by a termite that can snap its jaw three times faster.

If you're thinking this video looks a little unimpressive, that's because when you're filming at a ridiculous 460,000 fps, 128 by 128 pixels is just the best modern technology can offer.

What makes these tiny animals so cool is they've developed simple machines; latches and springs using nothing more than the power of evolution.

And these latches and springs are the key to their record setting speeds.

If you've ever played paper football, you know it's a lot easier to launch by flicking versus just swinging your finger around.

That's because you're using your fingers like a spring and latch.

Storing energy in your tendons and muscles, and then releasing it quickly, much faster than your muscles can move your finger alone.

And when you snap, well, you're doing what snap-jaw ants do when they push and slide their jaws past one another.

But you do all of these things way slower than the bugs do because you're a whole lot bigger and more massive.

Thanks to the laws of physics, humans can't handle anywhere close to these accelerations.

What is our limit?

Well, in 1954, to test what pilots could endure after ejecting at high speeds, Air Force physician, John Stapp, shot to 623 miles per hour in 5 seconds on a rocket sled, and slammed to a stop just one second later.

He experienced a record breaking 46.2 G's, and for, just an instant, his 168 pound body weighed over 7,700 pounds.

But remember that a froghopper can accelerate at 550 G's, and the mandibles of the snap-jaw ants pull over 100,000 G's.

That's insane.

They're able to do that because they're small.

We're both subject to the same laws of physics, us large mammals and those tiny, little bugs, but in a way, those laws apply to us very differently, how we move through water, how hard or soft that we fall, and how fast our machines can carry us.

You know, it's a good reminder that nature has figured out how to do things that we can still only dream of.

Stay curious.

Your hair swoop looks excellent in this-- Are my legs showing?

(Speaker) Nope.

Okay, 'cause where I'm sitting it doesn't look like I'm wearing pants.

[laughs]