If you know much about nature, it shouldn’t come as a surprise that it’s not an essentially meaningless instinctual thing. But it’s something people have wondered about for thousands of years. The first proposed explanation came by Pappus of Alexandria in the third century.
Pappus explained that only three forms could realistically be used in bee hives- triangles, squares, and hexagons. Pappus noted that hexagons could contain more honey in the same space as a square or triangle. Also, less material was required to build hexagons than squares or triangles. With squares and triangles, there would be extra spaces between the cells that would be basically wasted.
Is this true? Well it seems to still make sense today. You may know that bees are calculating machines and have been studied by mathematicians, so it certainly stands to reason that they would use the most efficient shape for their beehives.