If it no longer smells delicious lobster from the prey
In order to investigate the reactions of the experimental animals, the researchers did not rely on visible behavior, but the stimuli were detected at an earlier stage: They implanted the lobes of electrodes in the nervous system to be able to document directly via its signals, if the animals took weather had. The attractant was an extract of shrimp. When lobsters perceive this "fragrance", they usually react very intensively - they are almost mouth-watering. The nerve reactions that the researchers were able to detect via the electrodes were correspondingly clear.
However, if they applied the opaline to the lobsters on the antennas, the appetite response to the shrimp extract did not materialize. Analysis of the composition of opaline and further experiments suggested that this effect is not due to anesthesia, but to a mechanical blockage by the sticky consistency of this substance. She sits down on the sensory organs and makes them inaccessible to underwater scents. Thus, a hungry lobster can no longer perceive a sea hares as a source of food and loses his interest in the prey animal, the scientists conclude. This gives enough time for the sluggish water snails to wander off and thus move out of the danger zone. displayCharles Derby (Georgia State University) et al .: J. Exp. Biol. 216, 1364-1372 © science.de - Martin Vieweg