Tag Archives: biomechanics

Do Birds Have a Butt-Brain?

This summer, I worked with Dr. Monica Daley in the Structure and Motion Lab located at the Royal Veterinary College just outside of London. I was working on characterizing the function of a specialized spinal structure in birds and some dinosaurs known as the lumbosacral organ (LSO). This organ is hypothesized to function as a balance sensor by responding to changes in cerebrospinal fluid (CSF) flow, or by sensing strain in associated spinal ligaments. At its core, the spine is just a bony tube that surrounds the spinal cord, with CSF sloshing around between these two structures. When a bird experiences a disruption in balance, the LSO may sense this and restore equilibrium with a fast spinal reflex, instead of sending the signal up to the brain. This work has implications in physiology, motor control, and evolutionary biology. Firstly, this is a novel balance sensation mechanism that will give us a better idea of how bipedal land birds can quickly overcome balance perturbations. Their motor control strategy may be applied in robotics to create more efficient and resilient locomotor systems. Additionally, the LSO is thought to be important in the transition from dinosaurs to birds. Better characterizing its structure and function may shed light on this key evolutionary event.

 

The everyday life of a scientist can vary widely across labs and research projects. One of the many reasons I love biomechanics as a field is the sheer scope of techniques that I get to employ on a daily basis. While the core of my project involves simulating CSF flow on a computer, often times I find myself breaking up my day with hands-on work as well. For instance, I might begin a simulation in the morning, but conduct a balance perturbation experiment on a live guineafowl while the program runs. The next day I could be dissecting and staining specimens, commuting into downtown London to run CT scans, 3D printing an experimental apparatus, or writing code for numerical models. I get to feel like a biologist, mathematician, and engineer all in the same day.

 

Research is not always as glamorous as it is portrayed in high school and college courses. I often found myself frustrated with code or software that wasn’t working as I thought it should be, for seemingly no reason. Additionally, the results that you generate are often very difficult to interpret at a first glance. A large amount of my time was spent troubleshooting, writing data analysis scripts, and consulting colleagues to help develop intuition for the physical phenomena I was observing in my fluid dynamics simulations. Despite these struggles, I always felt inspired and motivated by the fact that I was conducting research that had never been done before. The reason why conducting sound experiments and interpreting data is so challenging is because it is literally uncharted territory. The intellectual rewards of making progress in a research project are very satisfying and often outweigh the struggles of achieving them.

 

Ethan Wold is a rising junior at Brown University in Providence, RI where he is majoring in Biology and Geophysics. At school, he works with Dr. Thomas Roberts studying the biomechanics of muscle and connective tissue in a variety of organisms including frogs and turkeys. This summer, he worked in Dr. Monica Daley’s lab in the United Kingdom studying the biomechanics of balance sensation in bipedal land birds as an IOSP fellow. After graduating, Ethan plans to do some traveling and conservation work, and then pursue a PhD in biomechanics or bio-inspired engineering.