Thomas S. Johnson Distinguished Professor of Biology Kent Dunlap Talks Necks and Brain Cells

Kent Dunlap, recently named Thomas S. Johnson Distinguished Professor of Biology, has been at Trinity College for 26 years.

Your website bio says that you “examine ways that scientists have uniquely approached phenomena in the humanities.” Can you say more?

As one example, biologists and neuroscientists have approached music—something that only humanists previously studied—to understand what’s in the ear and the brain that helps us appreciate the patterns that music makes. For me, I became interested in the neck both as an expressive organ in art and dance—for example, how a portrait artist positions the head on the neck and how dancers choreograph head movements—as well as a piece of our anatomy with so many diverse biological functions.

Why the neck?

Some of my interest in the neck comes from teaching anatomy, and some of it comes from my work as a potter—in crafting vessels with necks. I’m fascinated by this constriction in the body that people find beautiful and graceful but also dangerous and vulnerable.

I started to write my book (The Neck: A Natural and Cultural History, University of California Press) during COVID. When I had completed my first draft, I went back to one of my harshest writing critics—Mark Davis, my biology professor from my time 40 years ago as a student at Macalester College. I remember when he once returned a term paper to me, torn apart and redlined. But he convinced me there was an art to writing. When he read my book manuscript, he offered even more red ink!

Why hasn’t biology and evolution solved the problem of the neck’s fragility?

The neck has so many jobs to do that it’s hard to optimize them without introducing some vulnerability. For example, the way the larynx (voice box) is designed for speech: to accomplish our wide range of speech sounds, the larynx is positioned deep in the throat, but this placement makes the upper part of our throat floppy and susceptible to collapse when we sleep, causing sleep apnea.

We also inherited an imperfect design from our ancestors who didn’t have necks—fish. When vertebrates evolved onto land and breathed though lungs rather than gills, many of the leftover “scraps” from the gills became crucial structures in the neck, including parts of the larynx, tonsils, and swallowing muscles. Our neck is the product of improvised renovation rather than optimized innovation.

Speaking of fish, tell me about your current research.

Right now, I’m studying the effects of a newly introduced parasite on killifish, a freshwater species of tropical fish on the island of Trinidad. The parasite, which is introduced through food and gets into the gut, reduces the amount of cell birth in the brain and makes the brain smaller, influencing the fish’s behavior and ultimately its survival. Undergraduates Zoe Maggioni ’27 and Patrick Baum ’27 are working alongside me on this research.

This work builds on previous research on tropical electric fish in Panama and Uruguay, in which I examined how predators and social interactions influence the production of brain cells.

The brain is fascinating because for so long we didn’t realize that the brain had as much plasticity and could change form in response to the environment. Now, we are realizing that many animals modify their brain by adding new brain cells in response to environmental changes.

What—besides your research—do you do for fun?

I am a potter and a vegetable gardener. I construct papier-mâché birds, and I love to swim, travel, and cook.