Researchers continue to try to learn from differences in longevity and metabolism between species: "Haussmann studied cacti and turtles before zeroing in on a small, marine bird that contradicts traditional assumptions about aging. ... Leach's storm-petrels should die young but live a long life and break the conventional rules. First of all, they're small, and there tends to be a relationship between body size and life span. Elephants live longer than humans. Humans live longer than mice. So this bird shouldn't live long, but it does. ... His studies of storm-petrels have shown that certain characteristics of DNA - specifically lengths of the protective telomeres at the tips of DNA - are associated with species that live longer lives and possibly with how susceptible they are to cancer-causing tumors. ... [Bird species] with shorter life spans, such as zebra finches, lost their protective telomere caps quickly over time. Species such as the common tern, which lives to be about 30 years old, had less shortening over time." The petrels apparently produce more antioxidants as well - which may tie into the evidence suggesting that mitochondrial damage is the cause of shortened telomeres. Antioxidants slow the rate of that damage. The question remains as to where telomere length sits in the spectrum of cause and effect.

Link: http://www.bucknell.edu/x45446.xml