The Re-Origin of Species

What does a mammoth smell like? Do dinosaurs bob their heads as they walk, like today's birds? Do aurochs low like cows? You may soon find out.

From the Siberian permafrost to balmy California, scientists across the globe are working to resurrect all kinds of extinct animals, from ones that just left us to those that have been gone for many thousands of years. Their tools in this hunt are both fossils and cutting-edge genetic technologies. Some of these scientists are driven by sheer curiosity; others view the lost species as a powerful weapon in the fight to preserve rapidly changing ecosystems.