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.
... 33.8% from 25 to 44, 21.3% from 45 to 64, and 11.8% who are 65 years of age or older. The median age is 36 years. For every 100 females there are 96.3 males. For every ...