Evolution: The source of many, MANY questions

Evolution is an interesting subject, one that affects us all. Take a look at fossils you can find in almost every museum, and compare them to the knowledge we have of their current descendants. Note the similarities and the differences in the following two skeletons, The Prehistoric horse and the modern one:

 versus

 and if it's not easy to see, here's a close-up of some of the differences:

To successfully navigate their terrain, prehistoric horses were about 3 feet tall, lacked fetlocks,which are ankle joints, and had cloven hooves. Modern day horses average at twice that size, have their "ankle" joint further down, and their hooves have become solid. Why?

To put this more simply, I will stray from my example above, and instead wander off into the subject of beetles.

Let's say we have a beetle, and he's green. Now this beetle lives in the desert with an entire species of green beetles. The birds keep eating these easy-to-spy beetles until one, just one, is born brown. This brown beetle lives longer, and is able to have a ton of children, many of them are brown. Those children have more children, until the green strain dies out and the entire species becomes brown.

Ta-da! Evolution!
Make sense? I have a feeling I was all over the place there...