The Aphid Synthesizer: Un-Silencing Electropenetrography

• In Event: Nonhuman Innovations, Nonhuman Disruptions - II: Care & Mattering

Abstract

Electropenetrography (EPG) is a technique used by entomologists and agricultural researchers to study how aphids and other insects feed on the phloem of plants. Developed at the University of California - Davis in the 1960s by an entomologist and amateur radio tinkerer, EPG involves literally wiring an insect and plant together in an electrical circuit so as to track the feeding process through fluctuations in the electrical signal. In its earliest form, EPG provided auditory feedback by means of a Heathkit hobby radio amplifier and loudspeaker – constituting a sort of “aphid synthesizer”. As it became standardized as an experimental technique, however, EPG transitioned to solely visual feedback, jettisoning the audio output entirely by the mid 1980s. Drawing on interviews and participant observation with EPG researchers and their insect subjects, analysis of archival materials, and hands-on media archaeological engagement with obsolete EPG devices, I attempt to recover EPG's "audible past" as a site of insect-plant-human interaction. Echoing Joe Dumit’s 2014 account of early neuroscience experimentation (which similarly involved listening to the electrical activity of frog neurons) I consider the forgotten historical and potential future relations that sound and listening might have to the “plasticity” of EPG as an experimental technique – i.e., its ability to occasion playful interactions and surprising results regarding what the plant-aphid assemblage “cares about.” By suggesting the generative potential of an abandoned sensory practice - listening-in on insect feeding - I aim to complicate the idea of innovation in scientific experimentation, particularly with respect to the role of (non-muted) non-humans.

Author

• Owen Marshall