Archerfish: The fish That Recognizes Faces (Despite Lacking the Brains for It!)
Archerfish are already known for their unique ability to aim and spit water at insects perched above the water’s surface to knock them into the drink.
[Image of an archerfish spitting water at an insect]
but researchers have now discovered something even more surprising: archerfish can recognize and remember human faces.
A 2016 study published in Scientific Reports demonstrated this remarkable ability. Scientists from the University of Oxford and the University of Queensland tested how well archerfish could distinguish between human faces.
Traditionally,facial recognition was thought to require a large and specialized brain region (the neocortex) found in primates and some birds. However, archerfish lack a neocortex entirely, yet they still succeeded in the study.
Here’s how the study worked:
* Archerfish were trained to spit water at a specific face displayed on a computer screen above their tank, receiving a food reward for accuracy.
* After training, they were shown the trained face alongside up to 44 new faces.
the results were impressive:
* 81% accuracy identifying the trained face among 44 unfamiliar ones.
* 86% accuracy with more standardized images (removing color and head shape cues).
This proves the fish weren’t simply reacting to basic visual cues – they were genuinely recognizing faces. This is the first evidence of complex visual discrimination, like facial recognition, in a fish with a simpler brain structure.
How Do They Do It?
training a fish to spit at photos is already a feat, but it also challenges our understanding of intelligence and brain architecture in fish.
Humans rely on the neocortex for facial recognition. Archerfish, lacking this brain region, still managed the task. This suggests that complex cognitive abilities can develop in brains very different from our own.
This finding broadens our understanding of cognition across the animal kingdom, demonstrating that tasks like individual recognition don’t necessarily require large brains or “human-like” neural hardware.
Archerfish perceive the world differently than we do, adapted to a three-dimensional aquatic environment. Their visual systems are… [The article continues discussing their visual systems and depth perception].