Over the past four decades, scientists have made substantial progress in understanding the evolution of sleep patterns across the Tree of Life, including in primates. Remarkably, the specifics of sleep along the human lineage have been slow to emerge, which is surprising given our unique mental and behavioral capacity, and the importance of sleep for individual cognitive performance. Based on new phylogenetic analyses and other lines of evidence, I propose that human sleep is highly derived relative to other primates in three ways: evidence suggests that humans are more flexible in their sleep patterns than other great apes, and that human sleep is shorter and exhibits a higher proportion of REM than expected, compared to other primates. While many sleep biologists lament the continued erosion of sleep in modern life, these new findings suggest that natural selection has already been hard at work to shorten human sleep. I will identify some selective pressures that may play a role in favoring sleep efficiency in humans. More generally, I will consider how we can use new phylogenetic methods to better situate human evolution in a broader comparative context.