One of the most intriguing outcomes of casting our thinking about the world around us in mathematical terms is that phenomena that were thought to be quite distinct are instead revealed as being the “same.” Thinkers as long ago as Pliny the Elder made observations on active matter noting: “It is a peculiarity of the starling to fly in troops, as it were, and then to wheel round in a globular mass like a ball, the central troop acting as a pivot for the rest.’’ In this talk I will introduce field theory and the emergence of the modern theory of active matter as formulated by Toner and Tu to describe the collective motions of animals such as the giant herds of wildebeest on the plains of the Serengeti. We will then use active matter theory at a billion fold smaller scale to describe the motion of “flocks’’ of actin that power the movement of the single-celled parasites that cause malaria and toxoplasmosis. Our theoretical analysis will be used as a tool to interpret single-cell/single-molecule experiments on the dynamics of these fascinating parasitic organisms. All of these topics will serve as an invitation to a broader discussion of how the study of the living world is enriched by adopting the mindset that led Galileo to his assertion that the language of the natural world is mathematical.