Cradle-to-grave continuous monitoring of Drosophila melanogaster to quantify behavioral correlates of lifespan and healthspan*

Animal behavior changes and evolves over the course of an animal’s life. As animals age, they develop deficits across a broad range of behaviors that span many timescales, such as declines in locomotion speed and a loss of circadian rhythms. Measuring the period of time where animals are behaving 'optimally' (their healthspan) is difficult, and is often reduced to simple metrics such as climbing or running speed, which do not reflect the full range of animal behavior. Accurately measuring the complete spectrum of aging-related behavior changes and defining an organism-centric healthspan requires continuous, high-resolution monitoring to quantify differences at all timescales. We have designed a setup for continuous behavioral monitoring of the fruit fly Drosophila melanogaster over weeks and months, and have successfully recorded multiple animal lifespans of greater than 4 weeks. With this data we develop a definition of healthspan based on spontaneous, fine-grained behaviors such as grooming, spatial distribution, and circadian patterns or rest and feeding. We identify behavioral predictors of lifespan and healthspan, and investigate differences between male and female flies, as well as flies undergoing anti-aging interventions.