stereoscopic motion analysis in densely packed clusters 3d analysis of the shimmering behaviour in giant honey bees在密集的集群3 d立体运动分析分析在巨大的蜜蜂的行为.pdf

Kastberger et al. Frontiers in Zoology 2011, 8:3 /content/8/1/3 METHODOLOGY Open Access Stereoscopic motion analysis in densely packed clusters: 3D analysis of the shimmering behaviour in Giant honey bees 1* 2 1 2 1 3 Gerald Kastberger , Michael Maurer , Frank Weihmann , Matthias Ruether , Thomas Hoetzl , Ilse Kranner , Horst Bischof2 Abstract Background: The detailed interpretation of mass phenomena such as human escape panic or swarm behaviour in birds, fish and insects requires detailed analysis of the 3D movements of individual participants. Here, we describe the adaptation of a 3D stereoscopic imaging method to measure the positional coordinates of individual agents in densely packed clusters. The method was applied to study behavioural aspects of shimmering in Giant honeybees, a collective defence behaviour that deters predatory wasps by visual cues, whereby individual bees flip their abdomen upwards in a split second, producing Mexican wave-like patterns. Results: Stereoscopic imaging provided non-invasive, automated, simultaneous, in-situ 3D measurements of hundreds of bees on the nest surface regarding their thoracic position and orientation of the body length axis. Segmentation was the basis for the stereo matching, which defined correspondences of individual bees in pairs of stereo images. Stereo-matched “agent bees” were re-identified in subsequent frames by the tracking procedure and triangulated into real-world coordinates. These algorithms were required to calculate the three spatial motion components (dx: horizontal, dy: vertical and dz: towards and from the comb) of individual bees over time. Conclusions: The method enables the assessment of the 3D positions of individual