The title of this post (and the original article) is very misleading. Scientists are not "reviving proteins from billions of years ago". Currently, there is n

The title of this post (and the original article) is very misleading. Scientists are not "reviving proteins from billions of years ago". Currently, there is no technology that allows us to sequence DNA that is billions of years old (mostly because there is no DNA that is billions of years old). What the researchers are doing is inferring a probable sequence of the ancestor of many modern (currently existing) proteins. This inferred protein sequence can be expressed, and then assayed to test how its activities might differ from the modern proteins it was derived from. This is an exciting approach to exploring a possible evolutionary past, but nothing has been revived -- we cannot know whether the "revived" protein ever existed.