Because they fly.

Mom: -enters the bathroom and discovers a baby lizard- Why, hello baby lizard! -observes it's not moving- Is it dead or alive?

Me: I don't know. It's been there since afternoon.

Mom: -gets tissue to remove lizard-

Lizard: -starts running away-

Mom: Don't run! I'm trying to help! Do you want to live or die?

Lizard: -stops running and finally gets caught-

Mom: -picks it up and throws it out the window-

Me: . . .