The animal known for living in colonies and building complex nests is the termite. Termites are social insects that live in large colonies, which can consist of thousands or millions of individuals. They are known for their extraordinary ability to construct intricate nests, which can be above ground or subterranean. These nests can be remarkably large and sophisticated, featuring chambers for nurseries, ventilation systems, and food storage. Termites play a vital role in their ecosystems by breaking down cellulose in wood and plant matter, recycling nutrients into the soil. Their cooperative behavior and engineering skills make them fascinating subjects of study in entomology.