McKenzie-Smith Grace C, Wolf Scott W, Ayroles Julien F, Shaevitz Joshua W
Department of Physics, Princeton University, Princeton, New Jersey, United States of America.
Department of Physics, Wesleyan University, Middletown, Connecticut, United States of America.
PLoS Comput Biol. 2025 Feb 3;21(2):e1012753. doi: 10.1371/journal.pcbi.1012753. eCollection 2025 Feb.
Animal behavior spans many timescales, from short, seconds-scale actions to daily rhythms over many hours to life-long changes during aging. To access longer timescales of behavior, we continuously recorded individual Drosophila melanogaster at 100 frames per second for up to 7 days at a time in featureless arenas on sucrose-agarose media. We use the deep learning framework SLEAP to produce a full-body postural dataset for 47 individuals resulting in nearly 2 billion pose instances. We identify stereotyped behaviors such as grooming, proboscis extension, and locomotion and use the resulting ethograms to explore how the flies' behavior varies across time of day and days in the experiment. We find distinct daily patterns in all stereotyped behaviors, adding specific information about trends in different grooming modalities, proboscis extension duration, and locomotion speed to what is known about the D. melanogaster circadian cycle. Using our holistic measurements of behavior, we find that the hour after dawn is a unique time point in the flies' daily pattern of behavior, and that the behavioral composition of this hour tracks well with other indicators of health such as locomotion speed and the fraction of time spend moving vs. resting. The method, data, and analysis presented here give us a new and clearer picture of D. melanogaster behavior across timescales, revealing novel features that hint at unexplored underlying biological mechanisms.
动物行为跨越多个时间尺度，从短暂的、以秒为单位的动作到持续数小时的日常节律，再到衰老过程中的终生变化。为了研究更长时间尺度的行为，我们在蔗糖 - 琼脂糖培养基上的无特征区域中，以每秒100帧的速度连续记录单个黑腹果蝇长达7天的行为。我们使用深度学习框架SLEAP为47只果蝇生成了一个全身姿势数据集，得到了近20亿个姿势实例。我们识别出如梳理、喙伸展和运动等刻板行为，并使用所得的行为图来探索果蝇的行为在一天中的不同时间以及实验中的不同天数是如何变化的。我们在所有刻板行为中发现了明显的日常模式，为已知的黑腹果蝇昼夜节律周期增添了关于不同梳理方式、喙伸展持续时间和运动速度趋势的具体信息。通过对行为的整体测量，我们发现黎明后的一小时是果蝇日常行为模式中的一个独特时间点，并且这一小时的行为组成与其他健康指标（如运动速度以及活动时间与休息时间的比例）密切相关。本文介绍的方法、数据和分析为我们提供了一个关于黑腹果蝇跨时间尺度行为的全新且更清晰的图景，揭示了暗示未探索的潜在生物学机制的新特征。
