Incubation locations can refer to the places where eggs are laid and hatched, such as nests. Nests are typically built by birds, but some reptiles, amphibians, and insects also build nests. Nests are usually made from a variety of materials, including twigs, grass, leaves, feathers, and mud. They are often lined with softer materials such as fur or feathers to provide insulation and comfort for the eggs. Nests are typically built in trees, shrubs, or on the ground, depending on the species.