We humans often like to think we're the end of the line when it comes to evolution. But if we rewind through our short time on Earth as a species, and the many changes that have occurred to us along the way, we find we're still very much a work in progress. Renowned geneticist and author Spencer Wells reveals how changes in our genetic code have fuelled major changes in our appearance and capabilities over time, and why scientists believe we're continuing to rapidly evolve today. By understanding these changes, we are better prepared for the future.