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.
... from 18 to 24, 24.6% from 25 to 44, 28.2% from 45 to 64, and 20.7% who are 65 years of age or older. The median age is 44 years. For every 100 females there are 93.5 ...