Luckily for birds, they survived the mass extinction event that killed most of Earth’s dinosaurs. Four bird lineages lived through the catastrophe and over the next 66 million years, these feathered dino descendants radically expanded and diverged into the approximately 10,500 species living today. Because of their rapid early expansion, the relationships between modern birds have been incredibly difficult to tease out. Now, with 48 bird genome sequences in hand, researchers report online today in Science that they have finally been able to untangle some of the toughest thickets in the bird family tree. The slideshow above gives a tour of what scientists have learned from analyzing this amazing array of bird DNA.