Mamma knows best: why a generalist hummingbird selects the less abundant moss for nest building.

Many birds around the world use plant material to build nests that allow for hatching eggs and keeps chicks safe (Healy et al. 2015). Despite being a common phenomenon in nature, our knowledge of the mechanisms underlying how and why specific plants are selected for nest building is somewhat limited. Hummingbirds (Trochilidae) in particular depend strongly on plant materials to build their nests (Calvelo et al. 2006, Torres-Dowdall et al. 2007). Hummingbirds commonly use mosses as nesting material because mosses can retain moisture for long periods and thereby prevent eggs from drying out (Breil and Moyle 1976, Blem and Blem 1994).