Longevity, maximum lifespan, and life expectancy are not synonyms. LaserDiscs potentially had a much longer lifespan than videocassettes. Developmental genetic analysis examines the effects of genes over the course of a human lifespan. This was longer than a chicken's normal lifespan. Its maximum recorded lifespan is 24 years. Its average maximum lifespan in the wild is 7.3 years. There is no evidence for an effect of resveratrol on lifespan in humans, . Hedgehogs have a relatively long lifespan for their size. Behavioral genetics can account for the variability experienced across the lifespan. The breeding lifespan of a rabbit is variable. The Greenland shark has the longest known lifespan of all vertebrate species. A related framework for studying this part of the lifespan is that of emerging adulthood. The longest documented giant otter lifespan in the wild is eight years. The average lifespan in the wild is ten years. No average lifespan for an alligator has been measured.