Marine invertebrates as models for aging research

The oceans are home to many of the earth's longest lived animals with several species of non-colonial marine invertebrates documented to live for more than 100 years. Many of these animals grow and reproduce throughout their lifespans and there is no apparent functional decline or increase in mortality rate with age. Studying these animals may reveal some exceptionally effective defenses against the destructive process of aging thus providing a valuable alternative model for aging research. The life histories of commercially important marine invertebrates are well studied, but little is known of the molecular or cellular changes that occur with increasing age or the factors that determine lifespan. The objectives of this review are to present data on cellular and molecular aspects of aging in marine invertebrates with a focus on bivalves and sea urchins. This review will serve to evaluate their potential as model systems for aging and provide direction for future research efforts so that we can begin to understand the underlying molecular mechanisms responsible for the tremendous longevity and good health of key species.