[Talisker]

With shared walls between cells, why not just use squares? Less material, less calculation.

Answered my own question.

From article: "...hexagonal cells require the least total length of wall, compared with triangles or squares of the same area. So it makes sense that bees would choose hexagons, since making wax costs them energy, and they will want to use up as little as possible—just as builders might want to save on the cost of bricks."

[Vince Ferrer]

So it makes sense that bees would choose hexagons

How does it make sense? How did they arrive at the ability to calculate the amount of material they are using, and how to try different shapes and compare them? Once they arrived at their optimal calculation, how do they transmit this knowledge to the next generation?

[ShadowAce]

So it makes sense that bees would choose hexagons, since making wax costs them energy, and they will want to use up as little as possible—just as builders might want to save on the cost of bricks."

Yeah--because bees are experts at design. This article was written as if bees know why they use hexagons. Hint: They're insects. They don't have that sort of brain capacity.