Ernst Haeckel studied Medicine in Berlin and Würzburg and got a doctorate in 1857. He went on to acquire a doctorate in Zoology in Jena three years later. He taught Comparative Anatomy in Jena from 1862-1909. Haeckel was a prolific writer and intellectual and a staunch supporter of Darwin 's theory of evolution. However, he was less convinced about Darwin 's theory of natural selection. Haeckel discovered and named several species, invented a number of biological terms still in use today and proposed several biological laws, which however have been abandoned today.