FIGURE 60.4 Habitat fragmentation. (a) Increased fragmentation of forests has caused forest songbirds to come into increasing contact with the brown-headed cowbird. (b) The cowbird does not make its own nest. Instead, it lays its brown, spotted eggs in the nests of other species, such as this nest containing four blue eggs of the chipping sparrow

(Spizella passerina). (a: Jim Zipp/Ardea/Animals Animals; b: Paul J. Fusco/Science Source)