ECR Spotlight is a series of interviews with early-career authors from a selection of papers published in Journal of Experimental Biology and aims to promote not only the diversity of early-career researchers (ECRs) working in experimental biology but also the huge variety of animals and physiological systems that are essential for the ‘comparative’ approach. Leo Wood is an author on ‘ Flight power muscles have a coordinated, causal role in controlling hawkmoth pitch turns’, published in JEB. Leo is a PhD student in the lab of Simon Sponberg at Georgia Institute of Technology, USA, investigating neuromechanics, how nervous systems generate and control patterns of movement.
Leo Wood
How did you become interested in biology?
I assume like many people I've always been pretty fascinated by biology. My childhood fascinations with how birds flew or how dogs walk never really wavered; in fact, the more I learnt about biology, the more it really spiraled out into this endless complexity that was really entrancing. I love that we have scientific tools to parse apart the sort of basic questions any kid would ask: how do we think, how do we move? When I tell my legs to do something, what happens to make all those muscles work together and accomplish that? The reality that these are answerable questions, and that the answers require working with all kinds of juicy, interesting fields like physics, neuroscience, cell biology, and so on, is really compelling to me.
Describe your scientific journey and your current research focus
I started out in engineering, and used to do work that was a lot closer to metallurgy, developing shape memory alloy actuators. But I really loved the scientific side of my work, discovering new things, and was always fascinated by the complexity of biology, especially in the context of locomotion. Animals are just so much more capable and robust than robots at moving through the world, and compared with the artificial muscles people have developed, biological muscles are just so much more intricate and capable. When it came time for grad school, I decided to make the switch and really commit to biology by doing a master's studying muscle function in bird wings. From there, it's been a steady journey deeper into neuroscience and biomechanics. When you start looking at how muscles work, it's pretty hard to separate out or ignore the nervous system that's controlling all those muscles. These days, that defines an enduring puzzle for me: what are the common motifs and constraints on how nervous systems generate motor programs? Are there common principles we can learn that govern how all animals control their musculature?
How would you explain the main findings of your paper to a member of the public?
How do individual muscles contribute to flight in insects? For most flying insects, there are some muscles, aptly named ‘power muscles’, which provide the power for flight, moving the wing up and down. In this paper, we showed that these muscles not only provide power for flight but also are essential for controlling flight too, particularly in unexpected ways such as pitching the animal, or rotating it head-over-heels. Using really specific pulses of electricity, we can change when certain muscles are active in the wingstroke, allowing us to change one set of power muscles while the rest of the animal's muscles tried to do something completely different. We used this to show how these power muscles contribute to pitch turns, but also made a broader point; despite really carefully controlling when these muscles were active, we didn't get very controlled movement from the animal. This is because the rest of the animal's muscles weren't coordinating with what we drove specific muscles to do. This really teaches us that timing precision in animal motor systems only matters in the context of coordination; if muscles don't explicitly work together, it doesn't matter how accurate or specific certain muscles are, the resulting behavior won't be accurate or specific.
What do you enjoy most about research, and why?
I love learning about almost anything, so I find the kind of work we get to do as scientists really gratifying. In my experience, to study neuromechanics or animal locomotion, you have to know and use at least a little knowledge from so many different fields. A little bit of electronics, a little bit of muscle physiology, a little bit of software engineering, a little bit of animal behavior, even a little bit of surgical skills. It's a really satisfying blend of so many skills and ideas that I feel few other jobs have. Where else would you do mechanical design, machine learning and animal surgery, often in the same day?
What is the most important piece of equipment for your research, what does it do and what question did it help you address?
Basically everything I do, from measuring forces and torques to recording from neurons or muscles, relies on the good old fashioned combination of amplifier and analog-to-digital converters. It's helpful to know electronics when you do electrophysiology, but it really just comes in handy anywhere. Turns out most things we do in science really eventually break down to measuring a voltage and recording those values to a computer. If you're working in an animal without well-developed genetic tools and want to know when neurons or muscles are active, or even just how much force something is producing, you'll eventually need to amplify and measure voltages.
What is the most important lesson that you have learned from your career so far?
At a certain point in your PhD, if you're doing things right you'll find that nobody else, not even your advisor, knows as much about your problems and work as you do! I think many students don't really accept when that happens, and can convince themselves they're not experts (impostor syndrome is very real). Accepting your own expertise can save you a lot of headaches; everyone's seen students bounce around trying different things because their advisor recommended it, even though they probably knew in the back of their mind what would really work. It's a tricky balance, and you don't want to be overconfident, but many PhD students after a few years of work should make a conscious effort to trust their instincts. Don't be afraid to put your foot down from time to time, and say ‘we're doing XYZ’. You might be surprised how far that can take you!
What's next for you?
This paper really just scratches the surface of what you can do with moths; what other animal gives you access to the entire motor program for a behavior as complicated as flight, to a spike resolution? I've been working on some new projects to better understand the structure of these spike-resolution comprehensive motor programs, including recording motor programs from tons of really unusual and interesting lepidopteran species and recording descending neurons simultaneously with the motor program. I'm really excited for how these projects are going, and in general really happy with how much speed I'm starting to pick up. I think there really are general principles for motor control these kinds of techniques can teach us, particularly when it comes to how time constraints drive specific strategies for animals to generate motor programs with.
Leo Wood's contact details: Georgia Institute of Technology, Atlanta, GA 30313, USA.
E-mail: [email protected]
