For more than 150 years, since the publication of On the Origin of Species, biologists have focused on understanding the evolutionary chronicle of diversification and extinction, and the underlying evolutionary processes that have produced it. Although progress in evolutionary biology has been steady since Darwin’s time, developments in the last 20 years have ushered in a golden era of evolutionary study in which biologists are on the brink of answering many of the fundamental questions in the field. These advances have come from a confluence of technological and conceptual innovations. s. In the laboratory, the rapid and inexpensive sequencing of large amounts of DNA is producing a wealth of data on the genomes of many species; comparisons of these genomes are allowing scientists to pinpoint the specific genetic changes that have occurred over the course of evolution.