George Oster, professor in the Department of Molecular and Cellular Biology at the University of California, Berkeley, died on April 15, 2018. His death is a true loss for the scientific community.

George was one of the pioneers of interdisciplinary science. His tortuous career path is a testament to his refusal to allow his curiosity to be constrained by departmental boundaries. After finishing high school on Long Island, NY in 1957, George decided to attend the nearby U.S. Merchant Marine Academy (Kings Point, NY). After graduating in 1961, he shifted course and continued his education at Columbia University’s new Department of Nuclear Engineering, graduating. During his time at Columbia, he found himself drawn both to biophysics and the Bay Area (where he had spent a summer interning at Lawrence Livermore Laboratory), and joined the graduate program in Biophysics at the University of California, Berkeley shortly after graduating with his first PhD in 1967. There he worked with Aharon Katchalsky, a world-renowned Israeli scientist, on the thermodynamics of biological networks. After spending some time as a postdoctoral fellow in Rehovot with Katchalsky, George returned to Berkeley in 1972, where he would stay on as a faculty member for the rest of his life.

At Berkeley, George spent 2 years in the Department of Mechanical Engineering before moving to the Department of Entomology, his social and environmental conscience stirred by Berkeley’s electric political climate. “Berkeley was very exciting. I was into saving the whales and saving the world”, said George in a 2006 profile in PNAS. During this time, he wrote seminal work on caste and evolution in social insects (with Edward Wilson) and theories of bifurcations to a hierarchy of periodic oscillations and chaos in simple ecological models (with Robert May).

While most scholars are fortunate to uncover just one ‘great discovery’ during their careers, George was a self-proclaimed ‘dabbler’, seamlessly transitioning between fields, bringing to each his unique point of view and insight into some previously hidden natural order. Students and fellows would emerge from all corners of Berkeley’s campus for his lively ‘lab meetings’, held usually in some crowded and noisy North Berkeley café, to discuss their ideas – the wilder the better. Said George in 2006: “Most of the time, there is some puzzle to kick around. That’s what is fun about doing science. There is this endless supply of intriguing puzzles.”

With Garrett Odell, James Murray, and others, George pioneered mechanical models of morphogenesis, revealing how forces on and deformations of the cellular cytoskeleton integrate with chemical and genetic signals to give shape to tissues during development. With Alan Perelson, George proposed that the swelling of the cytoskeletal gel can drive protrusions at the cell front, laying the foundation for quantitative studies of cell motility. With Charlie Peskin, Hongyun Wang, Tim Elston, and others, George worked to understand how molecular motors can operate in a realm dominated by thermal fluctuations, culminating in the discovery and application of the Brownian ratchet to these biological machines. “It would not be an exaggeration to say that George, more than any other physicist or mathematician, inspired our current knowledge of molecular motors,” writes colleague Alex Mogilner.

Beyond these great technical contributions, George’s unique approach to science is what his many colleagues and collaborators will keep as his legacy. George was an early champion of the now common approach to solving biological puzzles through iterative cycles of modeling and experimentation, and will be remembered as one of the first biophysicists who ‘married’ experiments and theory.

George received international recognition as one of the most profound and original scientific leaders. He was a Guggenheim and MacArthur Fellow; he was awarded Weldon Memorial Prize by the University of Oxford, Winfree Prize by the Society for Mathematical Biology and Sackler International Prize in Biophysics. He was elected to the National Academy of Sciences in 2004.

His professional achievements are well-known of course. But those of us who worked with him will also remember him for his kindness, decency, and a mildly irreverent sense of humor. Our own personal recollections of George can be summed up as a mentor who knew when to give people space so that they could come into their own.

Padmini Rangamani (Postdoctoral Fellow, 2010-2014):

My fondest memory of working with George is the day I interviewed with him. The first question was, “Do you drink coffee?” We discussed projects, my thesis, and what I’d work on. And then I hesitantly mentioned that I was a mother of two children and one of them was a toddler and one a newborn. I was waiting for the typical line of question including how I’d propose to work and manage time and had my typical answers geared up. Instead, to my surprise, he said to me, “Oh my, you haven’t slept in so long. Let’s get you another coffee”. And then, he went on to tell me about another postdoc in his lab, who also had two kids and mostly worked from home. In his words, “We can always Skype but babies grow up fast”. As I remember him, this memory comes to mind as a stark example of supporting women in science — not policy, not rules, just simple acts of kindness and of course, that cup of coffee. And then of course, are his legendary depictions of how things in biology worked. We’d discuss membrane scission and he’d start drawing out diagrams and then end with a dramatic hand movement suggesting something akin to a wringing a chicken’s neck. He always strove to explain the physics in words and actions and the math came later. When we last talked, he said, “I’m sure membrane tension in neurons has something to do with Parkinson’s”. That was George to me, always thinking, always sharing ideas and having fun while going about it.

Jasmine Nirody (PhD student, 2014-2017):

The mentorship I received from George was anything from standard. He always provided me with exactly the amount of help I needed — no more, no less. More importantly, he knew how to explain things: He was always concerned with making sure one understood the physical intuition behind a process before whispering any hint of mathematical formulations. Before allowing me to write a single line of simulation code, George wanted to make sure I could properly replicate, with my finger, the 3D “kink and swivel” mechanism we proposed was driving torque generation in the bacterial flagellar motor. We practiced this until I had perfected it, and until eventually the barista at our local coffee shop began greeting us with a “kink and swivel” wave. Those hours of wagging our fingers over filter coffee yielded the first work that I felt truly, intimately connected to, and years later I used that same motion to introduce the mechanism in all my job talks. But, while George was constantly aware that one had to have the “right” physical intuition for a process to model it, he also always trusted, and let me follow, my “gut” intuition, even when it seemed crazy to him. I have been incredibly lucky to have had an advisor who let me stumble because he always believed I could get back up on my own, and, beyond that, lucky to have had an advisor who has not only been a great mentor, but also a great friend and ally. Undertaking a PhD can be a lonely task, but choosing to do mine with George made it decidedly less so. I hope in the years to come, my body of work will validate the confidence he has had in me.

His legacy lives on not only in the number of people trained by him and have gone on to establish successful scientific careers, but in the joy and passion he instilled in those fortunate enough to have worked with him. In a profile by the NAS shortly after his election, he was quoted as saying, “[Science] is so much fun that I would pay them to do it.” No doubt that his former students, trainees, and colleagues would echo this sentiment about their time spent sipping coffee and thinking through the great puzzles in biology with George.