Sir Julian Sorell Huxley FRS (22 June 1887 - 14 February 1975) was a British evolutionary biologist, eugenicist, and internationalist. He was a proponent of natural selection, and a leading figure in the mid-twentieth century modern synthesis. He was secretary of the Zoological Society of London (1935-1942), the first Director of UNESCO, a founding member of the World Wildlife Fund and the first President of the British Humanist Association. Huxley was well known for his presentation of science in books and articles, and on radio and television.

In the early 20th century he was one of the minority of biologists who believed that natural selection was the main driving force of evolution, and that evolution occurred by small steps and not by saltation (jumps). These opinions are now standard.  Though his time as an academic was quite brief, he taught and encouraged a number of evolutionary biologists at the University of Oxford in the 1920s. Charles Elton (ecology), Alister Hardy (marine biology) and John Baker (cytology) all became highly successful, and Baker eventually wrote Huxley's Royal Society obituary memoir.  Perhaps the most significant was Edmund Brisco Ford, who founded a field of research called ecological genetics, which played a role in the evolutionary synthesis. Another important disciple was Gavin de Beer, who wrote on evolution and development, and became Director of the Natural History Museum. Both these fine scholars had attended Huxley's lectures on genetics, experimental zoology (including embryology) and ethology. Later, they became his collaborators, and then leaders in their own right.  In an era when scientists did not travel so frequently as today, Huxley was an exception, for he travelled widely in Europe, Africa and the United States. He was therefore able to learn from and influence other scientists, naturalists and administrators. In the US he was able to meet other evolutionists at a critical time in the reassessment of natural selection. In Africa he was able to influence colonial administrators about education and wild-life conservation. In Europe, through UNESCO, he was at the centre of the post-World War II revival of education. In Russia, however, his experiences were mixed. His initially favourable view was changed by his growing awareness of Stalin's murderous repression, and the Lysenko affair. There seems little evidence that he had any effect on the Soviet Union, and the same could be said for some other Western scientists.  "Marxist-Leninism had become a dogmatic religion... and like all dogmatic religions, it had turned from reform to persecution."

Answer the following question by taking a quote from the article: What did Huxley believe?
natural selection was the main driving force of evolution,