VARIATIONS IN SENESCENCE AND LONGEVITY INCLUDE THE POSSIBILITY OF NEGLIGIBLE SENESCENCE

The variations in senescence observed in different species spall an en ormous range of rates that may be described by mortality rate doubling times. This review considers examples of very slowly senescing conife rs and fish from natural populations in which advanced age may not com promise reproductive functions. There is thus a basis for considering the possibility that some organisms may experience negligible degrees of senescence in certain environments. A tissue bank is urgently neede d to provide specimens of long-lived organisms fbr study of possible a nti-aging mechanisms that permit achievement of great ages.