One hundred fifty years ago today Charles Darwin’s On The Origin of Species was published. It is arguably the most important scientific work ever published. It was the product of painstaking scientific observation. Darwin was not only a scientist’s scientist, he was a great writer and populizer of science. It’s amazing to consider that Origin was written before much was known about genetics – yet Darwin’s conclusions still stand up to scrutiny. Darwin revolutionized biology – all modern biology is based on the principles of evolution.