Bees suddenly crash on the 'lake surface with no waves', why?

It is known that honeybees that fly freely in the sky lose their sense of altitude and crash into the lake when they fly over a 'mirror-like lake without waves'. A new experiment with a 'tunnel with mirrored ceilings and floors' reveals more about what causes bees to lose sight of altitude.

Floor and ceiling mirror configurations to study altitude control in honeybees | Biology Letters

There's a Really Weird Effect When Honeybees Fly Over a Mirror

In 1963, a team of entomologists Herbert Elan and Martin Lindauer conducted an experiment in which trained bees were made to fly a 'course across a lake.' From this experiment, if the water surface is rippling, the bees can reach their destination as usual, but if the water surface is not rippling and becomes 'mirror-smooth', the bees lose their sense of altitude and reach the lake surface. It became clear that they would collide.

The experimental results of Elan et al. Support the idea that 'honeybees are flying with visual clues.' With this idea, a new research team at the University of Aix-Marseille in France conducted an experiment using a special tunnel to see how bees adjust their altitude during flight.

In this experiment, the research team installed a 220 cm long 'tunnel with mirrored ceiling and floor' outdoors. At one end of the tunnel there was a starting point where bees took off, and on the other side there was sugar water as a reward. The research team then changed the conditions by hiding or not hiding the ceiling and floor mirrors with a 'cover that looks like a normal wall' to find out under what conditions the bees could or could not fly normally. rice field.

When the ceiling and floor mirrors were covered and hidden, that is, 'under the same conditions as a normal tunnel', the bees were able to fly to the other side of the sugar water without any problems. In addition, the bees were able to reach the sugar water even when the ceiling cover was removed and used as a mirror, that is, even under the condition that the height inside the tunnel was doubled upward from the viewpoint of the bees.

However, when the ground cover is removed and a mirror is used, that is, under the condition that the height inside the tunnel is doubled downward from the viewpoint of honeybees, the altitude starts to be lost after flying about 40 cm from the starting point. , I immediately hit the floor. Also, when both the ceiling and the floor are uncovered, that is, from the bee's point of view, under the condition that the top and bottom are mirrored and an infinite space spreads in the tunnel, the altitude starts to be lost only about 8 cm from the starting point. , I heard that I bumped into the floor.

In addition, the research team reports that even if the first half of the tunnel covered the mirror and the second half of the tunnel was uncovered to expose the mirror, the bees still hit the floor.

A series of experimental results suggest that bees use ventral visual cues to recognize altitude in flight. In other words, when the visual clues on the ground side are lost due to a lake surface or mirror without waves, the bees lower the altitude in an attempt to obtain visual clues, but the actual lake surface and floor are more than the bees recognize. Because they are so close, they accidentally hit the sense of distance.

Science Alert, a scientific media outlet, points out that the phenomenon of bees losing their sense of altitude is very similar to the

spatial disorientation that human pilots sometimes suffer. Spatial disorientation means that the pilot who flies in a situation where the horizon or horizon cannot be seen, such as in thick fog or at night, temporarily loses the sense of balance, becomes unable to grasp the attitude and direction of travel of the aircraft, and is the aircraft rising. It refers to a state in which you cannot even tell if it is descending.

When a person falls into spatial disorientation, he can manage to control his attitude and altitude by believing in the display of the flight instrument rather than his own sense. However, in the case of honeybees, there is nothing to rely on other than visual clues and sensations, so in a wide lake surface or a narrow tunnel where there is little information other than visual information on the ventral side, if you lose your sense of altitude, you will just crash. I can think of it.

A 2010 study using Drosophila found that flying Drosophila do not use ventral visual information to control altitude, and the same insect may have different systems to maintain flight depending on the species. It is said that there is sex.

in Science,   Creature, Posted by log1h_ik