Men sleep in consistent, regular patterns. Women, on the other hand, save up sleep. They store it like a battery. They tuck it away like squirrels do nuts.

Why? Because when they begin a relationship, they can draw upon their sleep reservoirs. They can stay up for countless hours without feeling the strain.

This always comes as a surprise to men at the end of a long date. I don’t just mean dinner and a movie; I meant an entire day and evening and a large chunk of the night. They both talk, and discover things about each other, and do things together, and finally around 3 a.m. they may decide okay, time to fall asleep.

He hits sleep like a ton of rocks; she fidgets uncomfortably. She looks at the ceiling. She glances at her watch. And finally, around 5 a.m., she jabs him with her foot until he stirs awake and mumbles: “Uhh...what’s wrong?”

“Something’s on my mind. Something important.”

“What is it?”

“I was wondering...what were you like in kindergarten?”