WORKS > Does an Ant like Glass or Sugar?

For this work, I made two piles of broken glass: one of actual glass and another of "sugar glass," fake glass made from sugar and often used in action movies. I released twenty live ants. My hypothesis was that the ants would gravitate to the sugar because they are almost blind and would follow the smell. However, they walked into the pile of actual broken glass and eventually died because of the sharp edges.
This created a new question: what are the qualities of real glass that we can recognize without seeing?