A Villager visiting and studying the cactus will earn some healing skills. This is useful for getting a doctor "started" (if there isn't anyone currently sick.) A trainee doctor has a better chance of healing than someone with no skills.
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Red Sox--2007 World Champions!
Celtics--2008 NBA Champions!

Isola is a magic island! All sorts of strange things can happen, and often do happen. -- arnie