creepy crawlies

considering I don't really like caterpillars, I am oddly fascinated by them. I spent the better part of my break taking photos of them. At one point I noticed a different coloured one and thought, cool. I took a photo and then I glanced up and there were literally dozens and dozens crawling around on the trunk of the tree. It looked like some had been squished or partially eaten or just died there, but many were still moving. I am going to try and track down a book to identify them... then I'll post a comment to update for anyone who might be reading.