Of all the mailboxes...

These ants chose mine.  It's a mystery to me.

At first I thought they were stockpiling grain or seeds but, with a closer look I realized they were moving larvae from the mailbox to the outside.

Not the clearest picture (they declined to stop and pose for me)

Even weirder, for the past few weeks, they would be there one day and gone the next then back a few days later and on and on.  I never knew what I would find going on in there from one day to the next.  They were not in my neighbors mailbox (I peeked).  Hum.