Does Laughter Really Cause Wrinkles, Or Do Wrinkles Just Cause Laughter?

Today I glanced in the rearview mirror while backing out of the drive and noticed something new. I stopped midway, put the car in park, and flipped the visor down thinking the lighted mirror would be more encouraging than the broad glare of daylight (and yes, I realize how ridiculous that sounds). Obviously there was no change. It was long and very defined and slightly disturbing. I smiled. I frowned. I used my index fingers to slightly tug the skin toward each temple on either side of my face. That worked... did wonders actually, until I let go. With a heavy sigh, I flipped the mirror back up and put the car back in drive.

So this is what they call a deep crease.
A no-doubt-about-it wrinkle.
Something even cover-up won't begin to hide.

I hear some of you moaning all ready. No, this is not the first wrinkle I've noticed on my face and I know full well there are many more to come. But this one was so there, so visible as if shouting to the world, Hey! Check me out! I comforted myself with all those feel good thoughts about laugh lines and love lines and just plain old life lines. I told myself it was only really noticeable when I smiled big so either

A). It's a result from all the big smiling I do every day, or
B.) I just won't smile big anymore and no one will notice.

And for anyone that knows me, either choice would be believable depending on the day and my mood. As I sat in the park a little while later waiting for a couple of kids to join the ride home from school, my daughter took a good look at me and said, "I love your hair! It makes you look waaaaay younger than what you really are!" Feeling a sudden boost of confidence, I pointed to my new found wrinkle.

"Wow," she frowned, "and you've got one on the other side, too."
There's just no end to the laughter around here.