We tend to think of human beings way up here in these terms, on the edge of the evolution branch. But it's kind of arrogant. From a useful beginning as scavengers of dead wood Eons before human beings began targeting them as pests, termites established themselves as key players in forest ecosystems around the world. Termites and some species of beetles are the only creatures able to break down cellulose, the chemical stuff of wood, and use its energy and constituent elements to make new life. The vast majority of the Formosans that develop wings and swarm die, many swallowed by birds, lizards and other animals.
Termites also return nutrients to the soil to be consumed by other insects and microscopic life.
They do it much faster and more efficiently than the microbes that cause wood to rot. It's cell walls. There's no protein, no nutritive matter. The advent of civilization, however, threw this ecological relationship askew. As humans turned away from a nomadic existence and began clustering in settlements and eventually cities, termites found a new supply of dead wood and water.