You’d have to look pretty closely at this tree to notice that there was a bug on it. The walking stick insects are very highly specialized insects that have adapted to their environments by blending in. You can probably guess that they are called “walking sticks” because they really look like sticks with legs. They come in many colors and sizes, all depending on the type of tree or bush they like to live in. The plants these insects live in are their primary source of food. Giant stick insects are some of the longest insects in the world. In fact, the longest insect on record is a stick insect of the species Pharnacia kirbyi, found living in the rainforests of Borneo, and it can grow up to 20 inches (50cm) long.