This phrase dates back to the 1800's and means a very long period of time.
Back then people thought that raccoons had very long lives. When they would greet someone that they hadn't seen in a while they would say "Why, I haven't seen you in a 'coon's age!" Apparently no one had ever really studied exactly how long a raccoon's life span is. Turns out that they average a five-year life span in the wild.
Who knew?
Well, it's better to have a small advantage than a large one that cannot be reached. This saying is said to have originated in a song called "A Bird in the Hand is Worth Two in the Bush," in which the bird is a synonym for a girl or woman.
Of course, these two Barn Owls created by IGMA Artisan Stephanie Brown could never be mistaken for two charming young ladies, but have all the detail and feathering to stand proud with their real life counterparts.
This saying is a little less obscure in its origin.
Since rabbits have such a short gestation period when reproducing offspring, you'll soon find yourself inundated with more bunnies than you'd care to count. I much prefer the whimsical alternative presented by Kristy Taylor and her "Multiplying Rabbits" to the real thing.