I think Jim was referring to what I called "floor vents". In your photo there are two floor-level side wall openings that exit to the outside. They appear to be air venting, or maybe designed as some sort of waste disposal ???

What ever they are, when you get tired of the tent, I want first bid on buying it from you. I have a mesa here that has that tent's name written all over it. It looks like it would root itself to the ground if you watered it. Brum