I agree Betty, and also even if you are familiar with the family you are researching it is extra easy to grab the wrong record on Ancestry and not notice. Ancestry gives "hints" to suggest records that are similar to the info you enter in your tree. If you tell it to accept that hint, it attaches the records and auto fills the form in for you. With a few quick clicks you may accidentally save the wrong info. And it also uses other's family trees to suggest things. So if one person gets the info wrong in their tree, the wrong info may be saved on multiple trees. The hint tools are helpful for quickly building a tree but there can be errors when people have not carefully researched the tree or taken their time looking at the info. JMO.
Yes! I think it's referred to as "hit and run" geneaology.
Reading the references now to those speculating about Nichols being the Zodiac. I'm not up on that investigation, but is there some DNA evidence retrieved from those crimes? If so, it seems they should have some kind of answer soon.
Re the questions about why Nichols created a false identity for himself in the late 70's, could it just be that he realized computer automation in record keeping was advancing and he didn't want to be tapped to pay child support? He seemed very frugal and avoiding it may have been a priority in his mind.