Tuesday, January 14th

In-Person Meeting
Virtual Zoom Option
7:30 PM EST

Visual assisted guidance reveals novel fly-object interactions

Sasha Rayshubskiy

Animals carefully evaluate the physical properties of objects in their environment. In this study, we use opto-motor-based visual guidance to repeatedly direct the fruit fly, Drosophila melanogaster, to interact with a small spherical object (a ball). We demonstrate that flies engage with the object through a limited set of behavioral motifs, some of which result in ball movement: the fly can walk onto and off the object, jump away while mounted on it, perform a “ball walk” – walking on the ball causing it to move – or pull the ball, also causing movement. We show that flies can detect whether the ball is moving and alter their behavior toward the ball depending on its mobility. When interacting with a mobile ball, flies consistently jump off throughout their interactions. In contrast, with an immobile ball, flies initially jump off but then show a marked decrease in jumping and an increase in mounting behaviors, suggesting a shift from initial caution to treating the ball as an integrated part of their environment. We also demonstrate that the flies’ ability to perform a ball-walking behavior that induces ball movement increases with time spent interacting with the ball, potentially reflecting a learned motor skill. Finally, we present results from a genetic silencing screen, showing that neurons previously implicated in social behaviors affect fly-ball interactions, suggesting common neural pathways between these behaviors.

Tuesday, December 10th

In-Person Meeting
Virtual Zoom Option
7:30 PM EST

What light pollution means for insect conservation

Avalon Owens

Rowland Institute Fellow

Nearly all species on earth use the sun, moon, and stars for self-orientation in time and space by attuning to celestial light cues that have been reliable for all of evolutionary history… until now. In the 21st century, increasing numbers of increasingly bright artificial lights extend the day, eclipse the moon, and obscure the stars even in nominally protected areas, with the night sky on average twice as bright today as it was only a decade ago. In this talk, I explore the ecological costs and evolutionary consequences of this transformation for insects. I look at how light pollution interferes with the bioluminescent courtship rituals of fireflies, and what it might mean for their future as cultural touchstones and flagship species. I also discuss moth flight-to-light behavior, a bizarre phenomenon leveraged in long-term surveys that is as harmful to moths as it is beneficial to entomologists, and ask how our perception of the conservation status of insects would change if the compulsion of the moth to the flame were subject to evolution by natural selection.