SUBJECT: Ph.D. Dissertation Defense
BY: Olga Shishkov
TIME: Wednesday, March 11, 2020, 2:00 p.m.
PLACE: Howey, N201
TITLE: Biomechanics of Black Soldier Fly Larvae
COMMITTEE: Dr. David Hu, Co-Chair (ME)
Dr. Cyrus Aidun, Co-Chair (ME)
Dr. Magnus Egerstedt (ME)
Dr. Peter Yunker (Physics)
Dr. John Brady (Caltech, Chemical Engineering)


The black soldier fly is a non-pest insect of interest to the sustainability community due to the high eating rates of its edible larvae. These larvae hatch by the thousands from eggs lad within rotting vegetation or animal carcasses. Startup companies all over the world raise these larvae on a diet of food waste, and sell them as feed for chickens and fish. Although numerous studies have been published on using these larvae as feed, little work has been done investigating the physical principles behind their behavior. In this thesis, we investigate the mechanics of their motion and apply this to new ways to raise larvae. First, we elucidate the mechanism by which groups of black soldier fly larvae can eat so quickly. We discover that larvae push each other away from the food source, resulting in the formation of a fountain of larvae. Larvae crawl towards the food from below, feed, and then are expelled on the top layer. This self-propagating flow pushes away potential roadblocks, thereby increasing eating rate. We then compress larvae to measure how quickly they respond. Live larvae come to the same equilibrium pressure as dead larvae, but they do so ten times faster, indicating that their small movements can rearrange them faster than just settling. When raised in plastic bins, the larvae can pile up in the corners, which allows them to break the bin or escape over its edge. We confine 300 larvae in flat vertical containers and measure that they pile up in corners once per hour. We drive the motion of larvae from corner to corner by pushing down on the peak of the pile, and breaking through the jammed larvae. To help raise larvae, we build an aerating bed to cool them from the heat generated by their metabolisms. Finally, we discuss the applications of this work to other feeding animal swarms and to robotics.