How do bats go to the bathroom if they are always hanging upside down?

Hi, Matthew:

I have a question regarding bats. You see, my mom runs with her friends, and they have nothing better to do while they are running, so they come up with questions like this. How do bats go to the bathroom if they are always hanging upside down?

-- Greg, the Net

You see, Greg, when you run your brain clonks around in your head, and that shakes loose weird questions like this. Stuff the rest of us keep to ourselves. And I think maybe there's something about the Spandex pressure that figures in too. Anyway, that's why I recommend for sound mental health you spend as much time as possible sitting quietly in a big chair, with your feet up, eating only very soft, creamy foods. It sure worked for me. I haven't had a weird thought since I started this regimen. You might suggest it to Mom so she'll stop embarrassing you in public.

But just this once we'll humor her and make a call to Bat Conservation International in Austin, Texas, experts on all things batty. So, we asked, how does all that bat poop end up on the bottom of the cave when the poop-making machinery points up? We find out right away, it's rough to generalize about bats. There are more than 950 species of the mammals worldwide, and they're pretty independent thinkers. But yes, they do spend at least some hours each day roosting upside down, and yes, they do poop. But their secret is, they don't do those two things at the same time. Bats sometimes go to the bathroom on the wing, so that's no problem. When they're snoozing in their roosts-- a cave, a tree, an attic and nature calls, they flip themselves right-side up, fire away, then flip back again. Most bats have a "thumb" along the top edge of their wings that can grip a roost as well as their feet can. And if you think pooping is tough, consider giving birth upside down. Many bats do that too. I won't run down the usual list of misconceptions about bats. Maybe you'll see the fuzzy flyers in a different light when you know that they help pollinate the blue agave from which we get tequila