How does sensory information drive animal behavior?
In order to address this fundamental question, my research operates at the intersection of multiple disciplines organized into three different levels: (1) sensory input (Visual Ecology), (2) information processing & integration (Neuroethology), and (3) behavioral output (Neuromechanics). I use stomatopod crustaceans, or mantis shrimp, as my primary study system due to their possession of two biological extremes: an elaborately complex visual system and one of the fastest predatory strikes.
Visual Ecology: In order to understand how a nervous system uses visual information to implement behavior, you need to know a lot about how that visual system works, what it is looking at, and what it needs to be able to detect to improve the animal’s fitness. A large portion of my published research is dedicated to understanding the visual ecology of mantis shrimp at all stages of their development. Studying mantis shrimp visual systems facilitates my ability to design appropriate visual stimuli for neuroethological experiments, and has also led to the discovery of several novel uses for photonic materials (Feller et al 2019; Feller et al 2014).
Neuroethology: The mantis shrimp strike happens so fast that there isn’t time to modify the movement once it is deployed. This means the circuit underlying mantis shrimp strikes is ‘open-loop’ or ‘feed-forward’ (instead of ‘closed -loop’ or ‘feed-back’), and that successful interception of a target must be predicted, or encoded in the nervous system, prior to striking. Since fast, predicted movements are performed by many animals (including humans), mantis shrimp offer a new opportunity to look for the fundamental neuroscience principles that govern such remarkable behaviors. I have pioneered several recording techniques, including an in vivo tether electrode method for recording from mantis shrimp nervous systems while they strike. Publications are forthcoming!
Neuromechanics: One of the challenges of founding a new study system is that most features of their biology are, well, new. Though we know a lot about the mechanics of mantis shrimp strikes, there is still much to be understood regarding the neural and muscular systems that drive these mechanics. Unexpectedly, I found that mantis shrimp actually pull the speed of their punches in when you make them strike in an unfamiliar medium (air vs. water; Feller et al 2020). Some of my most recent work seeks to elucidate the motor output controlling this behavior. While some of this work is currently under review, you can check out the mantis shrimp muscle recording system and teaching paradigm developed in collaboration with Backyard Brains corporation by my 2018 undergraduate mentee: Pollak, Feller et al 2019
New pursuits . . .
In addition to my work with mantis shrimp, my research has recently expanded to include the nightmarish group of insects known as Belostomatids, or Toe Biters. My students and I are currently working with this group of voracious predators to understand the role that vision plays in their ability to capture unsuspecting targets. Stay tuned for more to come on these fantastic bugs!
Portrait by Sam T. Fabian