In addition to many scientific publications, Heinrich has written over a dozen highly praised books, mostly related to his research examining the physiological, ecological and behavioral adaptations of animals and plants to their physical environments.
After he moved back to Maine and started teaching at the University of Vermont, his comparative work on insect physiology led to behavioral and ecological studies from the perspective of all animals (e.g., comparisons of food sharing between social bumblebees and territorial ravens).
[4] Heinrich's often popular books range from biologic detective stories (Ravens in Winter) to scientific specialties of field (The Hot-blooded Insects) to adventure and biography (The Snoring Bird) to human evolution (Why We Run).
[4] Heinrich has won numerous long-distance running events and set a number of open U.S. ultramarathon and masters (age 40 and over) records throughout the 1980s.
At the age of 39, Heinrich prefaced his masters career by winning the Golden Gate Marathon outright, with a time of 2:29:16, on a hilly course in San Francisco, California.
Combining his expertise as a physiologist, comparative animal biologist specializing in exercise and temperature regulation, and runner, he posits that the unique human capacity for long-distance running in heat is a human adaptation similar to running adaptations in other animals.
Another argument of the book was that humans evolved to be ultra-distance runners that could run down even the swiftest prey, through a combination of endurance, intelligence, and the desire to win (cf.
The film follows Bernd Heinrich over the course of a year as he reflects on his past and shares his ideas about nature, science, art, beauty, writing, and running.