Scientists know that chickens are related to dinosaurs. But what makes animals, including humans, so different from our ancestors -- or from one another? According to radical new research, not as much as you'd think. And tinkering with the building blocks of life may shed light not only on what makes us the way we are, but on the mysteries of evolution. Like a small but growing number of paleontologists, Professor Hans Larsson was attracted to evo-devo, or evolutionary developmental biology, because it opens up just this door to recreating the past.