The big picture of Darwin's writing concerns the survival of the fittest—the idea that individuals and species with desirable traits survive while others do not. This week's installment of Café Scientifique takes this theory to an even smaller level: pondering whether natural selection is ingrained on a cellular level. Though we as humans dread our impending old age, some scientists suspect that evolution may favor degenerative disease. Tonight, U of M evolutionary biologist Mark Decker discusses how Darwinian theories shed unique perspectives on longevity and even cancer—the most aggressive and prolific cell there is. Cells, the building blocks of life, may also hold the keys to how we can live a healthier, longer existence.— Jessica Armbruster