igenes/epigenetics and how do they differ from genes? Do epigenetics appear similar to any explanations of evolution that were covered in chapter two?...

What are epigenes/epigenetics and how do they differ from genes?  Do epigenetics appear similar to any explanations of evolution that were covered in chapter two?  If so, please explain the similarities.  If lifestyle/environmental factors can affect how our genes work, what are the possible implications?