It's amazing how strong ants are. I know that's not an original observation but when you see an ant haul around objects two, three, even four times their size--it's impressive.
In the picture above you can see the setting--one of my bird seed feeders that the ants are taking advantage of. I suspect it's as much for water content as for food. We're in the midst of a very long drought. The picture below illustrates the daunting journey that faces the ants before they get back to the ground and their home.