The main thesis of Monster of God, a nonfiction book by David Quammen, is the history of conflict between alpha predators, such as big cats and crocodiles, and humans.

Real-world examples such as these reinforce the book's main theme, or thesis. The author even analyzes films such as Alien, which depicts a predator stalking and inflicting violence on humans, and how such depictions in the mass media reflect our social relations with alpha predators.

From this thesis, Quammen explores different aspects of this fragile dynamic, which is sometimes volatile and sometimes harmonious. One of the themes, or sub-themes, in the book is how humans have mythologized predators throughout human history, dating back to the time of our primitive ancestors.

The alpha predators have often come to represent either a noble or evil deity—or, in the case of the lion of India, both. In his field research expedition to Lake Turkana, in Kenya, Quammen found that the crocodile, which killed numerous locals, became akin to the biblical Satan. However, the locals respected the crocodiles as much as they feared it.