Abstract

This study used records collated from the literature to examine the relationships for nest dimensions and female body mass and to ascertain the impact of phylogenetic relatedness. Large bird species do build bigger nests than smaller bird species but they tend to be broader with shallower cups. Differences between passerines and non-passerines are observed for most nest dimensions; nest cup diameter scales to the cube root of female body mass and is unaffected by this high level of taxonomic distinction. Lower taxonomic levels, i.e. Order and Family, have significant but varying effects on the different nest dimensions. The nest materials define the space occupied by the eggs and incubating bird and would offer structural support. It is not possible to dismiss a role for various nest materials conferring a different insulatory property to the nest that is unrelated to its structure alone.