Complex sentence: Marks also worked as a post-doctoral fellow with Archibald Howie and in in 1985, he worked with John M. Cowley at Arizona State University, before joining the faculty at Northwestern University.
Split into simpler sentences: Marks also worked as a post-doctoral fellow with Archibald Howie. In 1985, he worked with John M. Cowley at Arizona State University, before joining the faculty at Northwestern University.