Recently, I have seen several of the patrons at the Mesa Regional Family History Center copying information from online user posted family trees. There are probably dozens, if not hundreds, of websites that will allow you to "store" your genealogy files online. Some of these are free and other are free for small files, but charge for larger ones. The reasons for uploading your genealogy files used by the promoters of these sites includes backing up your files, convenience and collaboration with other family members.
When I first started investigating my family many, many years ago, I spent days and weeks in the Family History Library in Salt Lake City, Utah following my family line through the submitted 4-generation and 5-generation paper Family Group Records submitted by members of The Church of Jesus Christ of Latter-day Saints. At that time, none of this information was readily available online. This was long before the Internet arrived on the scene. Even in those ancient days, I realized that many (most) of the Family Group Records submitted by my erstwhile relatives were bogus. Dates, names, places were all a mish-mash of unsubstantiated claims. I spent years verifying the basic information on my lines and compiling a believable pedigree.
So now, I see the same problems, only magnified, online in various databases. I can't figure out if people cannot read, type or are simply brain dead when they enter the things I frequently find online. Perhaps you can understand why I am appalled when I see someone copying out information from an online family tree. When I questioned one patron, he said, "Oh, I just copy it out and then check to see if it is correct later." Yeah, sure. Well, maybe he actually does, giving him the benefit of the doubt. The problem is, how do you tell the bogus information from your real information? Maybe I need to have more confidence in my fellow researchers? Hmm, not after what I see online.
Here is a prime example. I did a search for my "test case" Great-grandfather, Henry Martin Tanner in the Ancestry.com Family Trees section. First of all, Ancestry.com does not find "Henry Martin Tanner" but comes up with entries for "Martin Henry Tanner." They are not the same person. Martin Henry Tanner was Henry Martin Tanner's great-uncle. There doesn't seem to be anything I can do to make Henry Martin Tanner come up first, unless I practically tell his life story in the search boxes. But, if I already know his life story, why would I be searching for him online? Perhaps that is another topic about why search engines in these large data bases ask for a lot of details on the individual. If you have the details, why would you be using their website?
After looking a the first few entries for "Martin Henry Tanner" (the wrong person), I noticed that many of the Ancestry.com Family Trees listed "sources." So, I looked further to see what people have been using as sources for Martin Henry Tanner. Here is an example:
Back to another search for Henry Martin Tanner and again, I get a list of Martin Henry Tanners, most of whom are the son of Nathan Tanner. These would all be my Henry Martin Tanner's cousin, since Nathan and Henry Martin Tanner's father Sidney, were brothers. This time I choose one with 13 sources, however, strangely enough, no parents are listed for this particular iteration of Martin Henry Tanner. According to this heavily sourced record, this Martin Henry Tanner died in Gransville, Tooele, Utah in 1935 which appears to be correct. Another strange thing is that in going back to the submitter's family tree, I cannot find any connection to Martin Henry Tanner. This is an orphan tree for this particular family. I never did get around to finding my own great-grandfather.
Enough. Like Alice in Wonderland, things keep getting "curiouser and curiouser." The moral of this story is rather obvious, before you step off into the fire swamp of online family trees, you had better be well versed in your own family lines. You may be able to find some useful information, but you can never tell if you are even on the same continent as the submitters.