Karel Liem built Harvard's fish collection into a global research powerhouse

Karel Frederik Liem, who spent 37 years at Harvard turning a neglected fish museum into one of the world's leading centers for aquatic biodiversity research, died at 73. He arrived in 1972 with a vision and a practical joke always ready.

Born in Jakarta in 1935, Liem came to Harvard after studying at the University of Indonesia and the University of Illinois. What he found in the Museum of Comparative Zoology's ichthyology collection was a problem: specimens gathering dust, facilities in disrepair, the whole enterprise running on fumes. He set about fixing it with the same energy he brought to his lectures.

A Teacher Who Made You Think

Colleagues and students remembered Liem for his warmth and humor—the kind of professor who could make a room full of biologists laugh while simultaneously pushing them to question everything they thought they knew. He didn't just teach fish anatomy; he created space for students to pursue their own research questions, launching many into academic careers. His approachability masked a serious commitment to rigorous thinking. He wanted his students challenging conventional wisdom, not accepting it.

That same drive shaped his museum work. Over three decades, Liem secured funding to renovate facilities, expand the staff, and grow the collection to over 500,000 specimens. Harvard became a destination for researchers studying aquatic life worldwide.

Cichlids, Feeding Mechanics, and Why It Matters

Liem's own research focused on fish diversity—particularly the cichlids of Africa's Great Lakes, which he helped establish as a model system for understanding how species evolve and diverge. He pioneered techniques like electromyography and high-speed video to watch fish feed in ways no one had measured before, revealing the mechanical sophistication hidden in a simple act of eating. He studied sex-changing fish, amphibians, and reptiles, but it was the cichlids that captured his imagination: thousands of species in isolated lakes, each adapted in different ways to survive.

This work mattered beyond academia. Understanding how fish adapt—how their bodies change, how they exploit ecological opportunities—offers insight into evolution itself. Liem's contribution was showing that you could measure this process, quantify it, build a science around it.

He served as President of the American Society of Zoologists and edited eight academic journals, but his legacy lives most vividly in the collection he rebuilt and the students he mentored. He is survived by his wife, Hetty, and their two children.