Sheep

• Mongolia's sheep outnumber its people 15 million to 2 million.
• You can tell the age of a mountain sheep by the rings on its horns.
• The fleece on a full-grown sheep weighs 8 to 10 pounds. Uncleaned, it's called "grease wool." Cleaned it's called "scoured wool."
• Sheep were used as the first lawn mowers, sort of. After cutting down the trees on their estates (so they could see attackers), English castle lords planted grass and then let the sheep keep it cropped.
• Sheep, like other cud chewers, have four stomachs. Because of this, they can't lie comfortably on their sides; they have to lie with their bodies upright. This may be the reason sheep's sleep is fitful, according to those who study such things.
• They say that sheep know which sheep are which. What's more, they can recognize which are which in photographs.