Natures wonders: dark eyed guppies are never lunch (Introduction)

by David Turell , Thursday, September 17, 2020, 21:51 (1310 days ago) @ David Turell

A weird technique to avoid being dinner:

https://www.scientificamerican.com/article/the-matador-in-your-fish-tank/?utm_source=ne...

"Guppies make unassuming pets, but in the wild they adopt a daring and counterintuitive tactic to avoid becoming dinner. When they spot a predator, they suddenly darken their eyes from silver to jet black—enticing the attacker to go straight for the guppy's head.

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"Robert Heathcote, a behavioral ecologist at the University of Exeter in England, says he came up with this hypothesis while eating a blueberry muffin on a train. He had noticed in high-speed videos that ambush predator fish called pike cichlids seemed to aim their attacks at the heads of the guppies with black eyes. “The guppy would wait right until the last minute and then kind of reverse itself and dodge out of the way,” says Heathcote, the study's lead author.

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"Pike cichlid attacks are ballistic and do not deviate from their course once launched, so the researchers could “simulate” whether a guppy would have escaped without the barrier's intervention.

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"These guppies may not be the only prey animals using such a strategy. Other fish also change their eyes' tint, and species including epaulette sharks and rock doves have attention-grabbing color patterns on their backs.

“This [study] opens a whole new area of research, and it might explain cases where eyes or eyespots are very conspicuous,” says Karin Kjernsmo, a behavioral and evolutionary ecologist at the University of Bristol in England, who was not involved in the study. “Maybe together with an evasive strategy, [these results] could explain why that is so.'”

Comment: A neat designed defense. This could not have developed over time or guppies would not have survived.