Do frightened guppies live longer?
Guppies can be divided in three groups: reckless, scared and normal (not very reckless and not very scared). During a test, these three groups were put together in an aquarium with piranhas. The piranha is a big enemy of the guppy.
The reckless guppies looked the piranhas straight in the eye and swam right at them. These guppies were soon all eaten. The guppies that were not really frightened but not very reckless either did not look the piranhas straight in the eye, but sometimes came close to them by accident. Out of this group, 15 % survived the test. The frightened guppies, on the other hand, avoided the piranhas as long as possible. Out of this group, 40 % survived the test. 60 % was eaten, but only after the guppies from the reckless and the normal group, cause these proved easy targets. Due to their fear, the guppies enjoyed a longer life.