Why is that fish afraid of tomorrow? Because it's Fry-day!
It was previously suggested that Trinidadian guppies have a “simple spectrum” of reactions to danger: while things aren't equally frightening, the fish would respond the same way to all of it nonetheless. That is, if they're a person, they would've responded to a lame and minimal shock from your brother the same way when they're lost inside a spooky haunted house--all of them. But a study may just have changed that thought.
“The idea of a simple spectrum is often put forward to explain the behaviour of individuals in species such as the Trinidadian guppy. But our research shows that the reality is much more complex," study's author Dr. Tom Houslay of Exeter University said.
They've observed 105 Trinidadian guppies as they subject these to regular doses of fear thanks to a heron named Grim or a predatory cichlid's constant visit on the side of the glass.
“Some of them go straight to the shelter,” said Houslay, an evolutionary biologist and the study’s lead author. “Some just stop moving, maybe hoping they won’t be seen. Some rush to the side and just swim up and down trying to escape.”
Researchers went on this much further and had each guppy injected of color-coded polymers for distinction. With this, they had a pretty interesting findings. “We see quite complex strategies; more complex than we thought,” Houslay said. “The variation isn’t just random. There’s something more meaningful going on.”
They found that fish are individuals with complex personalities! They're not all born equal--some fish are braver than others. "The differences between them were consistent over time and in different situations." These unique character traits may not be as complex as ours but this just proves that fish are all individuals.
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