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 64, and 16.9% who are 65 years of age or older. The median age is 39 years. For every 100 females there are 113.3 males. For every 100 females age 18 and over, there ...