Primarily Petroliana Shop Talk Forums Thread Like Summary - GB176 What are these holes for??

Been working on this thing for month and just noticed these.
The bottom ones attach it to the base.
I can't find a picture showing their use. Could they just be for ventilation?
What are these for??

I was going to silicone a piece of screen over them on the inside. I'm doing this at all openings in hopes of keeping the bees/hornets out.