[MUSIC PLAYING] [GUITAR STRUMMING] FEMALE NARRATOR: Here's one for you-- why did the tarantula cross the road?

Answer, he's looking for one of these-- a female's den.

Every fall, in this dusty corner of Colorado, thousands of male tarantulas get the itch to leave home and try their luck.

They're each sporting a new pair of tibial hooks, which males only get when it's time to mate.

Scientists call this change "hooking out."

Hooking out means it's time for hooking up.

But sealing the deal is a life-and-death affair.

The journey alone is treacherous.

This guy has run into his worst nightmare-- he's been stung by a tarantula hawk.

This massive wasp delivers the second-most painful sting in the world, at least by human standards.

The tarantula is paralyzed in minutes.

She'll drag him away, lay an egg on him, and use him as live baby food.

Yikes!

This one's survived the trek.

The female tarantula's silk blankets the ground.

This must be the place.

No doorbell, though, so he knocks.

He gently taps his front mouth parts, called pedipalps, to see if she's home.

Hope he's not expecting a warm welcome.

OK, here she comes.

Whoa!

OK, fangs are out.

She may be a lot bigger, but he has those hooks, remember?

And this is his chance to use them.

He clips the hooks under her fangs, blocking her most lethal weapon and tipping the balance in his favor.

Now, with his much longer legs, he lifts her body until she is nearly upright, holding her out of striking distance.

Then, using his pedipalps, the handoff.

The mating dance finished, he runs for his life.

She'll hold onto his little donation until she decides to make an egg sac, which she may not decide to do right away.

She has plenty of time.

Females sometimes live 40 years, way longer than males.

His days are numbered.

As a mature male, he'll be dead by winter.

If his luck holds, he'll mate again... maybe a few times before it's the end of the road.

Hey guys, it's Lauren.

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