Even the bugs and birds are different

There's something very interesting that I've noticed since being here.  There are no screens on any window.  The windows simply open to the outside and allow for the breeze and whatever else to drift in.  In the U.S., homes would quickly become infested with flies, mosquitoes, etc.  However, this situation does not pose a problem here.  The animals prefer to be outside, so while a small gnat may fly indoors, it simply pokes around for a minute or two and then exits back through the window.  Yesterday at work, a bird flew into the office.  No one seemed to mind.  So I watched.  The bird's friend soon followed inside.  They flew around the office, and then flew back outside once they were finished exploring.  Simply intriguing.