The ultimate mash-up, which means compiling together a lot of “stuff” (code like writing) was probably the Bible, where bits were quoted together and sometimes edited by busy scribes getting as much stuff as possible onto one scroll. The results were called “the Old Testament,” or “the Apochrypha” or “the New Testament” or “the Gospels.” If you try reconciling the four “gospels” that were finally accepted by the committee that reviewed and sorted all this mish-mash, you’ll see that they are irreconcilable, thus came from different origins. Scholars can tell from clues when something different was shoehorned into a pre-existing document, so if you have access to a “rainbow” Bible in which the different sources are in different colors, the mozaic nature of the text becomes clear.
Today’s term, mash-up, comes from music in which music from different sources are mixed up together. I suppose one could even say that Paul Winter’s ecstatic combinations of instruments and animal sounds are essentially a “mash up.” It’s the old idea of the two things that combine to create a third thing. Thesis, antithesis, hypothesis. So “mash-up” is not essentially anything but a strategy.
A “screen scrape” is something a little different. In computer terms (I’m quoting stuff I just learned so if I blunder badly, forgive me), most mashups are putting together bits of computer program that might not even be readable by a human being. These are in the interest of analysis or synthesis -- new ways of looking at information. A “screen scrape” is when you take material meant for human eyes and combine it with something else.
Now consider some stuff that has nothing to do with computers but everything to do with lawsuits. An excellent Montana artist has painted an abstract, stylized version of a familiar Charlie Russell painting of a cowboy riding his horse into a saloon. The pleasure of it is seeing in one's mind at the same time the abstracted forms and tweaked colors while remembering the traditional representational version. Consider the satire of “Gone with the Wind” which is the whole novel retold through the eyes of Miss Scarlett’s black slave. Consider the practice of taking the characters of a pre-existing (usually wildly popular) work like “Star Wars” and telling stories about them that were not in the original work. These are not quite mashups. Whether they violate copyright law is controversial.
Copyright is about “intellectual property.” That there stuff is what comes out of a creative mind, which in our ownership society is considered to be as much your property as a physical product like, um , an egg or work you have done: spinning, say, or typing or chopping wood. However, if you did this work while under contract to someone else or simply while on their salary, you cannot claim it as your property. One of the edgier issues has been whether someone who takes your very cells out of your body -- say by removing a cancer or your spleen -- and then uses those cells in research until the cell-line becomes valuable owes you any money. At one point when I went for a pap smear, I was asked to sign a release in case any of the cervix-scrapings turned out to be worth money. The nurse confided that it was a worthless document because the issue is STILL not resolved. Our technology is way out ahead of our law.
But even in the old-fashioned world, back in the Sixties, Bob Scriver discovered that a mold maker and casting company could make illegal copies of his work and sell them while the copyright law only prevented the guy from preventing HIM from casting his own work. A lawyer managed to make the thieves stop. No recompense, just a bill from the lawyer.
But then we visited a major Western art institution where the staff artist sat in front of a casting of a Remington and made a copy in a different scale by eye-balling it, and this was considered legal. Today in Asia there are factories where clever artisans sit copying American sculptures from photos. People buy them because they’re cheap. Many have no "eye" so see no difference and others just don’t care. For a while one of the Cowboy Artists of America wives got the idea that photos of the paintings by their husbands should not be on the art auction websites because they got copied, but then no one could buy them via the Internet. How could the customers know what they were buying? Dilemmas.
When I first started out posting writing on listservs and blogs, everyone was worrying about other people “stealing your work,” esp. in the Native American community where they are constantly obsessed with the idea that they’ve been robbed. (Of course, they have.) But then it occurred to me that posting something constitutes proof of prior existence, which is the key to most copyrights, and also that there are search engines that can find the copies easily, even in the devious homework of some resourceful kid. Besides, I'm always moving on and there's no money in it anyway. I give up on both copyright and property.
Lacking a clear legal set of guidelines, the moral issues raised by mashing music (whether the composer intended it or appreciates it or not) or screen-scraping art have been enforced by dint of outcry. That is, a great hullabaloo by watchdogs who come close to being an American Taliban, always on the alert for incorrectness, whether political or not. (Actually, it’s ALL political. There is no escape.) So if you’re big enough to ignore them, you can just thumb your nose. If you’re small and maybe vulnerable in some other way, like maybe being stigmatized for hiding your true identity (like Jehovah pretending to be a burning bush or maybe Zeus in the form of a bull or swan or golden shower (Ooooo! Naughty!), then you’re going to get slapped with lawsuit threats.
Now if you want to talk about biological mashups, we can either go to tions and ligers, or chimeras which are creatures like mothers whose babies have left cells of their different genome in their bodies after the pregnancy or twins who are born as singletons because they absorbed the other guy at an early stage. Genomic mashups happen all the time with viruses. That's how AIDS came to be.
Maybe the Bible is not the ultimate mashup. Maybe it’s meiosis, the biological process that is the basis of evolution when two genomes entwine to create a new creature, like a person. I suppose that a birth certificate is a copyright for a mashup child. With entitlement comes obligation.