Lifespan measurements of health and behavior in Drosophila melanogaster undergoing longevity-promoting treatments

The aging process alters how animals behave, from decreases in the frequency and speed of locomotion to weakening circadian rhythms. Longevity-promoting treatments such as rapamycin and metformin can significantly increase lifespan, but little is known about their impact on behavior throughout the aging process. A key requirement for a successful longevity-promoting intervention is the extension of healthspan (the fraction of an animal's life spent in good health) as well as lifespan. Historically healthspan has been measured with simple locomotion-based metrics that fail to capture the complete behaviors of an organism. We set out to study how behavior and health change over the course of complete lifespans of the fruit fly Drosophila melanogaster. We have recorded more than 100 male and female flies from two days post-eclosion until death across three treatment groups: control, rapamycin-treated, and metformin-treated. Our dataset of 41,474 fly-hours of high-resolution, high-framerate behavior measurement is suitable for modern techniques of computational ethology including deep-learning based postural estimation and unsupervised behavior classification. These data enable us to develop nuanced behavioral definitions of health that go beyond coarse locomotion metrics so that we can determine the effects of rapamycin and metformin on healthspan as well as lifespan. Further, we are also able to identify key behaviors within the first few days of life that predict lifespan.