evoloution

The intelligent design crowd says humans are far too advanced to have evolved, and therefore must have been designed, and that thus implies a designer. While there are a couple of logical fallacies in that conclusion, I'm more interested in the assertion that humans are designed. Off the top of...

When and how did skeletons evolve? Not exoskeletons, but the endo kind, like I have. And a related question, are all animals with endoskeletons vertibrates? Do all vertibrates have endoskeletons? Thanks.