Turning Nature’s Design into Human Innovation: Biology Postdoc Studies How Fish Inspire Improved Engineering

By Stephanie Godward, Communications and Marketing Director, College of Arts & Sciences 

Sarah Arnette’s childhood curiosity about animals never faded—it evolved into a career in research that fuels bioengineered innovations inspired by how fish function in their environments and beyond. 

“I never really grew out of that,” Arnette said. “I like the type of research that I do because I didn’t really have to choose between any one discipline. I always really enjoyed chemistry, math, biology, and physics, and I still get to kind of pick and choose from all of those disciplines rather than having to pick just one.” 

Arnette is a comparative vertebrate physiologist and biomechanist, which means she is fundamentally interested in how animals with backbones work. A postdoc now working in Assistant Professor Matt Kolmann’s lab in the Biology Department, Arnette is currently working on National Science Foundation-funded research examining how certain fishes can breathe out of water. 

“Broadly speaking, I am interested in how animals are shaped. Why are some things big and others small? Why do some things have no legs and some have very long legs? And how is that influenced by the environment that they live in?” Arnette said. 

A recent article she published focused on research on clingfish, which is one of many kinds of fish that have evolved with a suctorial disc – a suction cup on its stomach that is used to cling to rocks in the inner tidal.  

“It’s getting bashed by waves and is still able to hold onto these wet, mossy, slimy rocks,” Arnette said. “If you have ever used a traditional suction cup you might hang art with or stick something to your shower wall with, you probably know they don’t work very well. Most engineered suction cups only work in lightly wet, flat, smooth surfaces. But rocks in the inner tidal are basically none of those things.” 

Arnette’s research demonstrates how the clingfish is able to stabilize itself on mossy, wet rocks using its suction function, which has now inspired the creation of a new suction cup for humans to use in daily life. 

“My work on clingfish was inspired and informed by the work of Petra Ditsche, researcher and CEO of ClingTech Bionics. This company makes bioengineered suction cups based on the clingfish that outperform manmade suction cups because they can adhere to rough, slimy textures that outperform traditional suction cups,” Arnette said. 

Arnette’s current work with Kolmann is focused on the evolution of air breathing in a group of fishes called Anabantaria. These include common aquarium fish like betta fish and even invasive species like snakeheads.   

“If you have ever watched a betta fish at a zoo or a pet store, you might notice they swim to the top and gulp air; they are breathing air in those circumstances,” Arnette said. “We are interested in what organ allows them to do this – called the air breathing organ, or a labyrinth organ, in some fish. We are curious in what that structure looks like, how similar is it across the family, or across the group of fishes, and what environmental characteristics is it associated with?” 

Being able to breathe air is useful if fish live in mucky, murky ponds that tend to dry up seasonally or are covered with leaf litter or decaying matter that consumes a lot of oxygen before they can get it. 

Within the lab, Arnette also has the chance to lead and mentor other students. 

"We use CT scan imaging a lot, so students can get trained on how to visualize anatomy in 3D, which is really fun and applicable to a lot of medical and veterinary careers,” Arnette states. “I do histology – looking at tissues at the microscopic scale. We also have students who develop their own projects about other fish in the lab.” 

For students considering a career in science, research, or medicine or veterinary medicine, Arnette recommends talking to people in those fields and getting any internship or research experience that you can.  

“The reason for that is two-fold – one, see if you like it and if it’s for you. The second being you can build your CV that way,” she said.  

Kolmann said both students and faculty benefit from Arnette’s presence as a researcher and colleague. 

"I first met Sarah when she was an undergraduate REU (research experience for undergraduates) student at Friday Harbor Labs and it has been truly impressive seeing her prodigious development as a researcher, experimentalist, and a teacher,” Kolmann said. “Sarah has this knack for getting complicated experiments to work, like implanting teeny-tiny pressure sensors in live shark gills (and getting these sharks to swim in a water-laden wind tunnel). Sarah has led the charge on our NSF-funded research in the M.E.E.N. Fishes Lab, digitally dissecting and then annotating hundreds of micro-CT scans from fish specimens collected all around the world. Sarah has brought cutting-edge, open-source 3D imaging software to UofL graduate and undergraduate students and made these methods accessible to everyone. She's a landmark educator and stellar researcher and the lab couldn't do without her."