Srinivasan M V, Lehrer M, Kirchner W H, Zhang S W
Centre for Visual Sciences, Research School of Biological Sciences, Australian National University, Canberra.
Vis Neurosci. 1991 May;6(5):519-35. doi: 10.1017/s095252380000136x.
When negotiating a narrow gap, honeybees tend to fly through the middle of the gap, balancing the distances to the boundary on either side. To investigate the basis of this "centering response," bees were trained to fly through a tunnel on their way to a feeding site and back, while their flight trajectories were filmed from above. The wall on either side carried a visual pattern. When the patterns were stationary vertical gratings, bees tended to fly through the middle of the tunnel, i.e. along its longitudinal axis. However, when one of the gratings was in motion, bees flying in the same direction as the moving grating tended to fly closer to it, while bees flying in the opposite direction tended to fly closer to the stationary grating. This demonstrates, directly and unequivocally, that flying bees estimate the distances of surfaces in terms of the apparent motion of their images. A series of further experiments revealed that the distance to the gratings is gauged in terms of their apparent angular speeds, and that the visual system of the bee is capable of measuring angular speed largely independently of the spatial period, intensity profile, or contrast of the grating. Thus, the motion-sensitive mechanisms mediating range perception appear to be qualitatively different from those that mediate the well-known optomotor response in insects, or those involved in motion detection and ocular tracking in man.
在穿越狭窄缝隙时，蜜蜂往往会从缝隙中间飞过，平衡两侧与边界的距离。为了探究这种“居中反应”的基础，训练蜜蜂在往返取食地点的途中飞过一条隧道，同时从上方拍摄它们的飞行轨迹。隧道两侧的墙壁带有视觉图案。当图案是静止的垂直光栅时，蜜蜂往往会从隧道中间飞过，即沿着其纵轴飞行。然而，当其中一个光栅移动时，与移动光栅同向飞行的蜜蜂往往会飞得更靠近它，而与移动光栅反向飞行的蜜蜂则往往会飞得更靠近静止的光栅。这直接且明确地表明，飞行中的蜜蜂根据图像的表观运动来估计物体表面的距离。一系列进一步的实验表明，到光栅的距离是根据它们的表观角速度来测量的，而且蜜蜂的视觉系统能够在很大程度上独立于光栅的空间周期、强度分布或对比度来测量角速度。因此，介导距离感知的运动敏感机制在性质上似乎与介导昆虫中著名的视动反应的机制，或与人类运动检测和眼球跟踪所涉及的机制不同。
