Epiphany in the fish lab

Studying the brains of fish led undergraduate Danielle Katz in an unexpected direction – a degree in mechanical engineering.

When Stanford undergraduate Danielle Katz started her studies in human biology, she was eager to get hands-on experience. During a freshman seminar, she became interested in the work of Russell D. Fernald, a professor of biology, who studies the social behavior of fish.

I didn’t anticipate what it would be like to encounter dead-ends and go back to the drawing board.

Danielle Katz

“It sounded cool and I needed research experience, so I asked him if he would take any undergrads,” said Katz.

Soon after, Katz, a 2014 Bio-X Undergraduate Fellow, was harvesting the brains of A. burtoni, one cichlid fish species of the roughly 2,000 that live in Africa’s Great Lakes. She was studying the vagal lobe region of its brain, an area shown in other fish species to control mouth movement. After spawning, female A. burtoni carry their eggs in their mouths until they are ready to hatch, a behavior known as mouthbrooding. Other species of cichlids, called substrate brooders, instead leave their eggs in lake sediment.

One thing Katz learned in her work is that studying fish brains is not without its challenges.

Danielle Katz hangs her cross country uniform on the drying rack she designed in her mechanical engineering class.

Danielle Katz hangs her cross country uniform on the drying rack she designed in her mechanical engineering class. (Image credit: L.A. Cicero)

“Since it was my first research project, I didn’t anticipate what it would be like to encounter dead-ends and go back to the drawing board,” said Katz.

With some trial and error, Katz found that the vagal lobe was significantly bigger in mouthbrooding species. By staining A. burtoni brains with a fluorescent antibody, she also saw that the mouthbrooder’s vagal lobe may become more active during spawning.

After presenting her work at a Stanford Bio-X poster session, Katz found herself trying to design an apparatus to pick up one fish’s eggs and coax another fish to carry them in its mouth.

“I was drilling holes and gluing things together and cutting things and I thought: ‘Time is just flying by. Building these things is so much fun that I don’t even realize it’s work.’ That was my epiphany that I wanted to do mechanical engineering,” said Katz.

Even though her path has changed course, she recalls her time at the Fernald Lab fondly. “It was like family. Everybody there really made an effort to contribute to my learning,” said Katz.

Russell D. Fernald is also the Benjamin Scott Crocker Professor of Human Biology and a member of Stanford Bio-X, the Stanford Cancer Institute and the Stanford Neurosciences Institute.