A deeper dive into neural mechanisms of Drosophila color preference

Color preference in Drosophila melanogaster, which provides a novel paradigm for the study of biological rhythms, is a random process which exhibits dynamic patterns regulated by the circadian clock neural system together with other neuronal networks in the fly brain. Wild-type flies strongly avoid blue light throughout the day, preter green in the morning and evening, and switch to red light at midday. Previously, we have identified several genetic path ways that underlie these patterns (Lazopulo et al, Nature, 2019). To gain deeper understanding into these behaviors, we apply a Markov process framework, representing color zones as states and transitions as probabilistic movements between colors over time. Transition probabilities are estimated from experimental trajectories, capturing the stochastic nature of color choice and its temporal modulation. Different genetic manipulations are also shown differently in the model, including Rh7 protein-mediated blue avoidance, Rh1 protein-driven green preference, and s-LNv circadian neurons. This approach provides a quantitative basis for studying preference dynamics in simple animals.