Symposium honors long-time development and evolution researcher

The biologists gathering on the University of Wisconsin–Madison campus this Thursday, April 15, have one thing in common beyond their scientific interests in evolution and animal development.

All have ties to professor emeritus of anatomy John Fallon, who has worked and taught at UW–Madison for more than 40 years.

The John F. Fallon Symposium on Limb Development and Evolution will be held from 8:15 a.m. to 5:30 p.m. on April 15 in the Health Sciences Learning Center. The symposium is free and open to the public.

The symposium was organized by anatomy faculty members Grace Boekhoff-Falk, Anne Griep, and Youngsook Lee to recognize and honor Fallon’s long career and many accomplishments in both research and service.

The afternoon session of invited speakers features some of the most prominent names in evolutionary and/or developmental biology, including Neil Shubin from the University of Chicago and Provost of the Field Museum, Cliff Tabin from Harvard University, Marian Ros from the Universidad de Cantabria in Spain, and UW–Madison’s own Sean Carroll.

“Everyone we invited accepted right away, which is a real tribute to John,” says Boekhoff-Falk.

The morning session includes a dozen of Fallon’s former students, collaborators, and mentees. His approach to mentoring scientists at every stage of their careers is one thing that makes Fallon stand out, Boekhoff-Falk says.

“John has been just an incredible mentor, for nearly every group of people you can think of on campus. Of course he’s done a stellar job with his own graduate students and postdocs, and he also has served on the mentoring committees of numerous junior faculty, many of whom continue to seek his advice post-tenure,” she says.

As director of the UW–Madison MD/Ph.D. program from 1989 to 1996, Fallon re-energized the program, guided all entering students, and laid the foundation for what is now the Medical Scientist Training Program. He has also mentored a number of students and faculty members at other institutions, several of whom will speak at Thursday’s symposium.

Fallon, the Harland Winfield Mossman Professor of Anatomy, is widely known in scientific circles for his extensive work to understand how limbs and digits form during development. He has also studied the patterning and evolution of other surface structures like feathers, scales, and teeth.

“Everyone knows John’s work, you learn it in intro developmental biology,” says Shubin.

Though he officially retired last December, Fallon is still hard at work both in and out of the lab. He is teaching two courses this semester, including a brand-new embryology course that he developed with Youngsook Lee.

Despite his quiet demeanor, he’s not one to shy away from controversy or challenge. His research has repeatedly countered long-held views about how limbs, fingers, and other structures develop.

“Even in the last couple of years, he’s shaken up the field again. People thought they knew where distal limb structures came from,” says Boekhoff-Falk. Then, in a 2008 paper, Fallon identified a tiny cluster of cells in an unexpected place at the tip of the forming chicken limb that gave rise to all the digits. “When he put this model out there, there was a huge uproar in the field — a lot of controversy and people were challenging him at conferences… He’s been breaking old paradigms and establishing new ones, over and over and over again.”

While Fallon will close out the symposium with a talk focusing on his own recent research, the breadth of the presentations speaks to the true extent of his influence. “In science, you also live on through all the ideas you’ve had and kindled in other people, and the students you’ve sponsored and so forth,” says Shubin.

After a fruitful four decades at UW–Madison, Fallon is looking forward to traveling and spending more time with his seven grandchildren.

“This business is consuming, and it’s very difficult to give yourself totally because your mind is always working,” he says.

But, he adds, “I will miss working in the lab with people who are smarter than I am. It’s challenging and engaging and a wonder that you can get paid to do it.”