How about the remnants of an implant or operation he is due to get and is scheduled for but hasn't yet. No idea how those investigating it would know he's due to get it though although maybe you could have it so they tell him the skeleton is genetically identical to him although the skeleton has had an implant and the guy figures out himself that it's his body from the future. The police would tell him that while the implant is new to the market it appears to be x amount of years old and haves them totally baffled
What about something not unique but very unlikely? For example, the character in question could've been a punk in his youth and deformed his skull in some unspecified but very particular way, he finds the deformed skull and that by itself it's freaky, since his skull shape itself is kind of a secret (maybe even technically doubtful before he actually tried, with no previous cases existing and such).
Adding the physical proximity to his house to that very uncommon trait would be enough to at least assume the skeleton is related with him.
Is there a way to test if something's from the future? No.
We would never be able to tell if something was from the future. The object might appear older then it should be, or of technology that doesn't exist yet, but how would we eliminate other possibilities and know it's from the future. We would have to wait until the future had become the past before we could know.
For example: The year is 1960, and a iPod falls out of the sky onto the ground. How would someone tell if this iPod was from the future, aliens, or some top secrete government agency. If you turn the iPod on you might find some dates and clues, but you couldn't get onto the internet, because there was none in 1960. So, the information you've taken from the iPod could be incredible fiction. You will not know until time passes and the iPod is invented, manufactured and falls into the past.
Originally posted by Quincy
So the protagonist doesn't find out it's his skeleton, but the constant reader does after he lives the rest of his life and is buried there?
Well, what the reader knows and what can be done in science are two different things. Plus, why does a good story have to be scientifically correct?
Originally posted by Quincy
What if the skeleton has a particular injury that the protagonist has yet to have, but is affected with before the story ends?
What would be more messed up is if he only sustainaed the injury because he was investigating how the skeleton came to be there in the 1st place.
Originally posted by Mindship
I could see the story easily as a classic Twilight Zone episode.
Well there is a twist ending that leads to the character realizing something about his personal life that causes him to grow as a person after first using the skeleton for fame and fortune, so yeah, it's very Rod Serling like. 🙂