<human>:  Who invented the honeycomb structure?
<bot>: Honeycombs are a natural phenomenon. They are formed by bees using their specialized glands. The bees use these glands to mix a liquid called nectar into a foam-like substance called propolis. The bees then deposit the propolis onto a branch, and the propolis hardens into a honeycomb. The bees use the honeycomb to store food, water, and pollen.