Wild Fish Can Recognize Humans Based on Clothing
A fascinating study from the Max Planck Institute of Animal Behaviour in Germany has revealed that wild fish, specifically saddled seabream and black seabream, can distinguish between different humans based on their clothing. While it's common for family pets to recognize people, the ability of wild animals to do so is intriguing.
The research, published in a scientific journal (though not explicitly mentioned as Biology Letters), involved experiments conducted in open waters of the Mediterranean Sea. Led by Maëlan Tomasek and his team, the study aimed to understand whether wild fish could differentiate between two individuals based solely on visual cues like clothing.
Experimental Design
The experiment consisted of two phases:
- Training Phase: A diver trained a group of fish over 12 days by feeding them while swimming a certain distance. The fish quickly learned to follow this diver consistently.
- Diver Differentiation Phase: Another researcher joined the experiment. Both divers sometimes wore identical diving gear and at other times wore equipment with different colored patches or flippers. They swam in different directions with food rewards only available for following one specific diver.
Findings
In tests where divers wore different equipment (30 trials), both species more frequently followed the diver who provided food rewards, indicating they learned whom to follow based on visual cues like color or patterns.
However, when both divers wore identical gear, black seabream were unable to distinguish between them. Saddled seabream showed some preference for following their original trainer during mid-experiment but not consistently throughout.
"Overall," said Tomasek, "when we wore identical gear, there was no evidence they could tell us apart."
The team suggests that these findings demonstrate how simple mechanisms—such as recognizing patterns or colors—can be used by fish to differentiate humans without prior interaction with humans.
About the Study
The researchers utilized differently colored diving equipment to test whether wild saddled seabream and black seabream could distinguish between individuals.
