The Secret to Longevity in Tubeworms | Science Blog:
With an incredible lifespan of up to 250 years, the deep-sea tube worm, Lamellibrachia luymesi, is among the longest-lived of all animals, but how it obtains sufficient nutrients -- in the form of sulfide -- to keep going for this long has been a mystery. In a paper just published in the online journal PLoS Biology, a team of biologists now provide a solution: by releasing its waste sulfate not up into the ocean but down into the sediments, L. luymesi stimulates the growth of sulfide-producing microbes, thus ensuring its own long-term survival.
A worm without this adaptation would survive, but the first that directed its waste down lived longer. This is evolution at work.