The Department of Biological Sciences evolved from the merger of two of the oldest departments in the Faculty of Science: the Department of Botany and the Department of Zoology. Botany, founded in 1949, turned 50 in 1999; and Zoology, founded in 1950.
Professor Lam Toong Jin, Head of Zoology (1981 - 1996), then Director of School of Biological Sciences (1996-1998) and finally Head of Department of Biological Sciences (1998-1999) handed the headship baton to Professor Hew Choy Leong in October 1999 and Professor Paul Matsudaira took over the headship from 2009.
There was a School of Biological Sciences, briefly, for two years when the former Botany and Zoology first merged. The University subsequently changed the name to Department of Biological Sciences in 1998.