The Sibley-Munroe checklist was a landmark document in the study of birds. It drew on extensive DNA-DNA hybridisation studies to reassess the relationships between modern birds.
... to 44, 28.7% from 45 to 64, and 13.9% who are 65 years of age or older. The median age is 41 years. For every 100 females there are 98.0 males. For every 100 females age ...