On this second installment of DeLTAcast, Matt Kayser joins hosts Eric S. Jackson and Mark Blumberg to talk about that humble creature, the fly, and what it can tell us about sleep and development. Matt, an Assistant Professor in the Department of Psychiatry at the University of Pennsylvania Medical School, disabuses us of the notion that flies are so simple and evolutionarily distant from mammals that they can't possibly help us understand ourselves. Like humans and all other mammals, flies sleep more when they are young, a fact that Matt is using to probe the brain of these tiny insects to unravel the mysteries of sleep.