Estimates range between one and two million for the number of animal species that inhabit the earth.
In its most basic sense, Zoology is defined as the scientific study of these animal species. However usable this definition was up to the last third of the 20th century, it no longer has much currency today and zoologists see themselves as people who are interested in the integrative and comparative biology of animals. The focus of zoologists is organismal biology which is the glue bonding molecular and cellular biology on the one hand and ecology on the other. The programs in Zoology at the University of Calgary strive to give students a sound foundation in animal organismal biology. This is achieved in the context of the fundamental approach to scientific education used by the Department of Biological Sciences.