Most empids use plant fibers as nest material, but the members of Branch 2, which nest on ledges, build their nests of moss. Perhaps the solid ledge foundation makes it unnecessary for them to weave a nest, for the ledge-nesting phoebes (Genus Sayornis) also build their nests of soft material that is simply laid on the ledge.

Click here to continue the story of Empidonax evolution with a look at egg pigmentation.