 Although Huxley was opposed by the very influential Owen, his conclusions were accepted by many biologists, including Baron Franz Nopcsa, while others, notably Harry Seeley, argued that the similarities were due to convergent evolution.A turning point came in the early twentieth century with the writings of Gerhard Heilmann of Denmark.An artist by trade, Heilmann had a scholarly interest in birds and from 1913 to 1916, expanding on earlier work by Othenio Abel, published the results of his research in several parts, dealing with the anatomy, embryology, behavior, paleontology, and evolution of birds.