In Life Everlasting: The Animal Way of Death, physiological ecologist Bernd Heinrich encourages us to see death as a starting point for life, with dead matter feeding organisms throughout the ecosystem.

Humans preserve dead bodies with chemicals, but in the natural ecosystem there is no such thing as waste. What can we learn from the animal way of death?

We make things that are very difficult to recycle: chemicals that don’t break down, plastic that doesn’t disintegrate. In many cases we destroy the whole ecosystem by destroying the animals involved in the recycling—vultures, predators. We end up with dead bodies, for example, that are not recycled because the animals that do that are gone.

Did researching this book shift your ideas about the cycle of life?

Definitely. There are things that we can really feel good about—how a caterpillar turns into a butterfly is sort of a reincarnation. The more I thought about recycling in the animal world, the more I thought we should be more conscious of it.

You’ve set records running in marathons and ultramarathons. Has your experience as an athlete affected the writing of this book?

If I were objectively looking at humans, I would see a really amazing animal that is a super athlete. Looking at us as an animal species affected my training—I could see similarities in endurance and physiology between different animals. We are linked with beetles and butterflies and bees and birds.

You’ve written many books about natural history for a popular audience. How does this writing affect your academic research?

What’s real is always more fascinating and complex than anything in your mind. When I looked at the larger context, in order to present the material to somebody outside of my specialized niche, I would see new things, and that helped my research.

You start the book by discussing a request from a friend to be buried at your farm in Maine. What did you ultimately decide to tell your friend?

What he wants to do is against the law. I can’t just leave him out there for the ravens; they might not come, and someone else might find him in the meantime. If the ecosystem was still pristine and my friend’s body was left out there or I was left out there, in a few hours everything would be gone. But you can’t do that now. This problem underscores the importance of a natural ecosystem. In the end, I didn’t want to make any specific suggestions; I just wanted to teach about life, describe some beautiful animals, and throw out some ideas.