Fish are often seen as creatures with simple minds. Many even believe that they have short intention spans and short-term memory loss.
On the other hand, are fish really as dim-witted as they’re made out to be?
Image Credit: sh.aquarium.com
A new study published in the journal Scientific Reports suggests that fish have the ability to distinguish between two different human faces, a quality that would require not only a mental capacity large enough to make a differentiating observation, but also that would require a form of intelligence.
The study involved the use of archerfish, which are capable of shooting streams of water from its mouth in such a way that it becomes a blob just before it impacts a surface. This is a technique that the archerfish uses to take down bugs and other prey in the wild, and this type of fish was chosen for the job because they can indicate a choice very clearly.
After displaying two separate human faces each time from an array of over 44 different face sets, the archerfish would then respond to the individual faces by shooting their little water jets at either one face or the other to indicate their choice.
Training for this study took anywhere from a few days to a few weeks per fish to teach them to actually spit at a certain face.
After selecting one, the archerfish were presented with a treat, and just as you would train a dog, the archerfish were eventually trained to select one specific face and were treated every time they selected it.
Soon enough, it became clear that the archerfish would only react to the face that it would get a treat from, and they were able to select the faces with anywhere from 77-89% accuracy, which is remarkably high.
The findings reveal that the archerfish were capable of differentiating between the different types of faces, and may have misjudged them only a few times either because a face looked similar to another, or because the fish believed they would get a treat from it.
This probably means that your pet fish knows who you are and knows your face, but it’s unknown if different species of fish have the same level of intelligence or not.
Source: CNN, Wikipedia