Ouroboros looks at the humble yeast in context: "Our understanding of aging in animals owes a great debt to a large body of careful work in a single-celled organism, the brewer's yeast Saccharomyces cerevisiae. Indeed, as I've argued before, yeast is one of the two organisms with the strongest credible claim to have started modern biogerontology. An unusually large crop of yeast aging papers have appeared over the last few months, and I thought it would be appropriate to spend a few paragraphs describing them - in honor of this humble organism that rises our bread, ferments our beer, and has done so much to open our eyes to the fundamental mechanisms of aging. ... yeast mutants in worm longevity genes are significantly more likely to be long-lived than randomly chosen mutants - suggesting [that] genes that modulate aging have been conserved not only in sequence, but also in function, over a billion years of evolution. ... Given this functional conservation, it is reasonable to use yeast to help answer questions about aging in general, so long as these questions as cell-biological in scope."