Insect nests are structures built by certain species of insects to provide shelter and protection for their eggs and young. The two most common types of insect nests are anthills and niduses. An ANTHILL is a mound of soil created by ants, which is usually found in open areas such as fields or meadows. A NIDUS is a nest made of silk and other materials, which is typically found in trees or shrubs. Both types of nests provide a safe environment for the insects to reproduce and raise their young.