Why does the moon look so big when it's rising?

Almost everyone has noticed the same effect: the moon indeed appears larger when it is close to the horizon than when it is overhead. Yet you can prove to yourself that this is strictly an illusion. Hold a dime at arm's length in front of the moon. Regardless of the moon's elevation in the sky, the dime will just cover it.

The "moon illusion," as it is sometimes called, is entirely conjured up by the human brain. There are still several explanations for what the actual process might be -- some contend it's brought about by having terrestrial frames of reference right near the moon when its rising (trees, houses, telephone poles, etc.), allowing the brain to "focus" on it more closely.

Another theory says the illusion centers of the human perception of the sky as an overturned bowl, more distant on the horizon than overhead, which fools the brain into "correcting" the size of the moon for that scenario. In any case, here is a final test to prove that it's all in the mind. When no one is watching and the full moon is near the horizon, bend over and
look at the moon upside down from between your legs (!). The effect vanishes, presumably because you have flipped the scene reaching the brain by placing the horizon above the moon.
http://oldsite.smasweb.org/faq.html
http://www.space.com/scienceastronomy/solarsystem/bigmoon_000105.html

Why do male dogs lift up one leg to pee?
Dogs descend from wolves and packs of wolves in the wild have certain territories. They establish their territories by marking the perimeters with urine. They males lift a leg and pee on a tree so any passing wolf will be able to smell it and know he better get out of the territory that isn't his. So it's to pee higher.
As for the females, both cats and dogs, lions and wolves squat. The female doesn't have the dominate role (except in hyena packs) so they don't need to mark their territory like a male does.
http://answers.yahoo.com/question/index?qid=20070613015514AAdmfGC