Recording and behavior differences.

Adult moths from framily Spingidae (i.e. hawkmoths or sphinx moths) commonly feed on flower nectar through an extended proboscis, often several centimeters in length and longer than the body of the moth. Feeding on a viscous liquid (nectar) through a long and narrow tube is a challenging fluid dynamic problem and the subject of long-running scientific investigation. Here we characterized the relationship between proboscis submergence depth and nectar drinking rate in Manduca sexta hawkmoths. Video recordings of moth feeding bouts were collected and neural networks were used to extract data by object localization, tracking the location of the nectar meniscus and moths’ proboscis tips. We found that although feeding rates vary among bouts, the variation was not associated with proboscis submergence depth. These results show that despite the theoretical possibility of fluid uptake through the walls of the proboscis, such effects do not have a substantial effect on nectar uptake rate, and suggest that nectar must traverse the full length of the proboscis.天蛾科（Sphingidae）的成年蛾类通常通过伸长的喙（proboscis）吸食花蜜，该喙通常长达数厘米，甚至长于蛾类自身躯体。通过细长管状结构取食粘性液体（花蜜）是一项极具挑战的流体动力学问题，也是长期以来科学研究的热点课题。本研究以烟草天蛾（Manduca sexta）为对象，量化分析了其喙浸入深度与花蜜吸食速率之间的关联关系。研究团队采集了蛾类取食过程的视频录像，并通过目标定位的神经网络提取数据，追踪花蜜弯月面（meniscus）与蛾类喙尖的位置变化。结果显示，尽管不同取食回合间的吸食速率存在差异，但该差异与喙的浸入深度并无关联。本研究结果表明，尽管理论上存在通过喙壁吸收流体的可能性，但该机制对花蜜摄取速率并无显著影响，这提示花蜜必须经由喙的全长完成输送。