The fish meticulously wait their turn in the narrow passages to avoid crowding

about the episode

The tropical neon tetra – a small fish about 3 centimeters long with bright colors native to South America – has elegant manners. If a school of these fish encounters a narrow fairway, they don’t all try to squeeze in first, no, they form a neat row.

Researchers discovered this during experiments in which a school of 30 such fish were made anxious in a tank by passing a fishing net through them. A move the fish, of course, avoided as quickly as possible. Well, each tank had a small hole through which it could escape, which varied in size from 1.5 to 4 centimeters.

And the researchers saw that the fish didn’t move away unexpectedly faster through the larger openings, because they also fit together there, of course. But whatever the size of the hole, they moved through it at a constant speed, without bumping into each other, and the last few fish were a little slower than the rest.

What the researchers think is that the fish are waiting their turn, so as not to get too close to other fish and not cause crowding. Similar behavior has already been observed in ants in previous research. On the other hand, humans and sheep do not excel at all in orderly evacuation of space.

It’s nice to know that fish are better at something than us, but according to the researchers, this knowledge could also help develop swarms of robots and manage traffic flows from self-driving cars and crowds of people.

Read more about research here: Neon tetras form queues to avoid jams.