Remembering Suzanne Eaton

If we had been bros, you would call my relationship with Suzanne a "quid-bro-quo-mance". Of course we were not bros, and many people here felt a unique and special bond with Suzanne. She made us feel that way. Still, I feel that Suzanne and I are kindred spirits.

Suzanne and I shared many interests in common. We were both developmental biologists; meaning scientists who try to understand how in the world a single cell, the fertilized egg, turns into an entire animal. We were both developmental biologists who also saw ourselves as cell biologists; meaning scientists who want to understand the inner workings of cells and cell communities. This was not entirely normal, at least not at the beginning of our careers.

Suzanne and I went through most of our scientific lives independently. I grew up in New Orleans, Suzanne grew up in CA. I came to CA for college but Suzanne went to Brown in Rhode Island. I did my PhD at Stanford. Suzanne at UCLA. Suzanne moved to UCSF and I moved to the east coast, where I would stay for 25 years as Suzanne settled in Europe. We kept just missing each other. Our scientific paths gradually converged, but it was not until relatively recently that our physical paths crossed. In 2013 my husband and I moved from Johns Hopkins in Baltimore to the University of California, Santa Barbara. That summer, to my delight, the Kavli Institute for Theoretical Physics at UCSB started a program in Morphogenesis. The idea was to bring physicists and biologists together to tease apart how cells build complex structures. Suzanne was a leader. She stayed at UCSB for the full six-week program. This was the first time I really got to know her. She needed supplies from my lab for her course. We cycled up the big hills next to campus. I invited her over to my house. She recommended that I read “Sapiens, A Brief History of Humankind.” I dutifully did. It’s a great book. Three years later, Kavli held the summer course again. To my delight, Suzanne returned. At the time, participants had to stay in dormitories and from what I gather the accommodations were pretty basic. So I made it a point to invite some of the visitors to my house for dinner at least once during their stay. Suzanne came for dinner and we had such fun that she stayed for the remaining few weeks. We cooked dinner together. We talked about science and books and our kids. We swam in the pool and soaked in the hot tub. She relished the five-mile bicycle ride to campus each day. When the hot water heater went on the blink at my house, she gamely took ice cold showers each morning. I wimped out and heated water on the stove for mine. She claimed to enjoy them, said they were “invigorating.” I felt at that time as if I had found a long lost sister.

One day, we attended a special seminar together, sitting on the floor because the room was overflowing. It was 2016 and gravitational waves from black holes colliding had just been detected for the first time. One of the special features of the Kavli Institute is that you will have a course on black holes going on next door to one on embryos and one day the lecturers have to switch. A black hole person speaks to the biologists, and a biologist tries to explain embryos to the black hole class. So we were there to hear one of the gravitational wave discoverers describe that discovery. For Suzanne, this was mind candy. She even dared to ask a question. I don’t remember the precise phrasing of her question but I do remember the answer because it was unforgettable. The answer was that gravitational waves do not dampen as they travel through the universe. This is why we can detect them 1.3 billion years later.

Suzanne was known and widely admired for the original and insightful questions she asked. Because she was so broadly knowledgeable and deeply curious, she saw everything in a unique way. So when Suzanne asked a question, you knew both the question and the answer would be interesting.

Similarly, Suzanne’s scientific contributions were broad and unique. She wanted to understand how in the world a single cell could build itself into an animal. Think about it. That would be like a skyscraper or a 747 not only building itself, but building every part of itself along the way, each part sliding into precisely the right place. How in the world. Suzanne wanted to understand how cells organize themselves to build complex organs and tissues. Any organ. Any tissue. From beautiful butterfly wings to zebra stripes. She focused most of her attention on the fruit fly wing. We shared a fascination with fruit flies.

All of the tens of trillions of cells in your body contain the same 3 billion bits of information that is your DNA. Each cell acquires its particular characteristics, from our thinking brains to our beating hearts, by virtue of which of the bits of DNA that particular cell decodes and puts to use. That is an astonishing secret of life, but it is not the whole story.

Suzanne wanted to understand how cells function as communities. She wanted to understand their social lives and their means of communication. While most cell and developmental biologists were focusing on genes and the proteins they produce, Suzanne got interested in lipids, greasy substances that are much harder to study. She found that powerful proteins called morphogens could be packaged up into tiny lipid particles that move from cell to neighboring cell or even circulate freely in the body. Her results were original, her ideas provocative and sometimes controversial. She then got interested in how cells communicate mechanically, pushing and pulling on one another, shearing and stretching, to produce the final shape of the wing. She collaborated with physicists, diving deeply into the underlying mathematics, a prospect that strikes fear into the hearts of most biologists. But Suzanne was intrepid. And very good at math. What appealed to Suzanne about tissue mechanics is that extremely complex, coordinated movements of thousands of cells could be reduced to relatively simple mathematical formulas.

The last time I saw Suzanne was in Galveston, Texas in January 2019 at the Gordon Research Conference on Directed Cell Migration. There is a photograph widely circulated on the Internet of Suzanne walking along the beach in Galveston with a Ferris wheel in the background. There were ~200 people at that Gordon Conference but I had memorable and meaningful interactions with Suzanne. Back to our bromance, we watched a total lunar eclipse from that beach. We also took a long walk along that beach, commiserated about challenging personnel, and shared what our kids were up to. As we walked and talked, Suzanne searched for seashells. I asked Suzanne for a book recommendation and she gave me the book she had just finished. Milkman by Anna Burns. It is still on my nightstand.

The very last time I saw Suzanne we were jogging in opposite directions on that beach in Galveston. We were not jogging together because we did not want to slow each other down. Suzanne jogged toward me grinning wildly and holding up a prize. She had just found a large and completely intact shell; she radiated childlike delight and wonder. This is how I remember Suzanne.

I am not ready to let her go. We must keep her brilliant, her radiant, spirit alive. I remember Suzanne every time I walk on a beach, and I live and work very close to the beach so this is often. Let us all channel our inner Suzanne every time we ask a question at a talk (now in chat), and maybe that question will be a little more original and a little more insightful as a result. Let’s think of Suzanne whenever we read a stimulating book whether it’s about history or politics, literature, philosophy, or cosmology. Let’s think of Suzanne whenever we marvel at the wonders of the natural world. At conferences all over the country and the world, we will run/walk/jog together for Suzanne. In this way Suzanne’s brilliant and beautiful spirit will keep traveling through the universe, undampened, just like those gravitational waves.