How long are your legs?
My friends know that I'm willing to come up with a theory for anything. I'm embarrassed to say I was completely stumped when someone asked me to speculate how the bilateral parts in our human bodies "know" to stop growing at the same length/size.
The legs I can imagine because we're constantly pounding on them and I can imagine them "evening out". But the arms? Ears and eyes for that matter? I know that hormones are involved in the cessation of skeletal growth, but that doesn't fully cover it from my limited understanding.
I'll probably look it up eventually.
BTW: Abraham Lincoln was once asked "How long to you think a man's legs should be?" His answer was "Long enough to reach the ground".
Why are manhole covers round?
Riddle: Say, if you read this far, perhaps you like riddles? Here's one of my favorites: Why are manholes and their covers round? (They weren't always that way, I believe an easier-to-fabricate octagonal shape was favored in the early days.)
Answer: It turns out that a round cover is the only shape that can't fall through it's own hole! I don't know about you, but I sure wouldn't want to be in a sewer, but if I WAS, I wouldn't want a 300 pound manhole cover falling on my head!
