Sir John Gurdon and his contributions to understanding fundamental principles in developmental biology

I have had the pleasure of attending many conferences with Sir John Gurdon and have always loved to hear his insightful ideas, whether talking about "reprogramming", "community effects", or a "ratchet" mechanism for interpreting biological gradients. Throughout his long and distinguished career, John has made important discoveries and has remained a leading figure in developmental biology for over six decades, a remarkable feat in itself.