Ensure the availability of a resource colony of non-human primates (Macaca nemestrina-pigtailed macaque) for use by investigators for aging research, and to develop a battery of tests of biological markers of aging suitable for monitoring the rate of aging in primate species. Collaborating investigators will perform compatible studies which add to the age characterization of the species. The battery of tests developed will be suitable for use as a measurement instrument to test interventions in aging processes and to test hypotheses regarding the role of genetic or environmental factors in rates of aging. The following three tasks will be performed: maintain and make available for research a resource colony and data base; biomarker development and testing; and final biomarker panel.