Why do scientists think "fingerprint" island used to be vineyard ?

The mediterrranean island of spin along a was once used to isolate lepers from the mainland rose believes fingerprint island may have been build for a similar purpose you get a very similar layout it's asymmetrical they're these tiny little compounds layrinth theme layout it's meant to keep people in but as ROS closes  in on fingerprint  island all is not as it seems from the satellite image but is this that's it these aren't dwellings i mean there's a couple little structures there but they look like temporary places with shade so i think we can throw the lepercolony out the window i really need to get a look at the place up close ROS head straight to the nearest section of crumbling wall if you look at the wall it doesn't have any mortar it's all dry stone it hasn't been locked into place they're just kind of lumping gaint rock on top of each other it's a vital clue  to the island's purpose island infact is full of these long strips these are agricultural fields these are not dwellings these dry stone walls are not weight -bearing they're not used for structural purpose but rather their primary purpose is to clear the ground of debris once the ground has been cleared in this way it's ready for growing crops but agriculture requires water and satellite image shows no evidence of streams or lakes Rose searches for clues and soon makes a discovery yes eureka it's well than how it all makes sense this is why they're here on the island because there's fresh water there's source of fresh water here the next step is to figureout  what the farmers were growing on this island and whether they left any clues in the soil yep and this pretty much answer the question what were they growing here this is an old grapevine thr lsbyrinth seen from space is a weired vineyard dating back hundred of years it's an interesting choice to put a vineyard on an island probably one of the most remote and bizarre vineyard ever this soil romanian there's source of fresh water here is perfect for growing gruper