Several researchers recently compiled nest trait databases which grouped bird nests by their structure and attachment types, as well as their heights, sizes, materials and sex of the builder. Nests of woodpeckers (cavity), weavers (dome), and robins (cup) demonstrate some of the variety among nest types. The researchers found that the most common nest structure is cup-shaped, and most are secured through the bottom of the nest.
A bird’s nest is primarily a place for birds to lay, incubate, and hatch eggs, and many species also raise offspring in the nest. It makes sense that harsh climates would put evolutionary pressure on birds to build more protective nests. One group of researchers looked at how climate influenced nest architecture among tanagers, a family of birds using a wide variety of nest types. They noted that dome-nesting species were found in drier, windier places with higher solar radiation, while deep cup nests were built by species living in locations with strong winds. These species’ nest adaptations offered more protection from dry and windy conditions.