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  Lﾃδｶnnstedt and her colleagues saw it for themselves while watching damsel fishﾃつ�in a custom-built tank in which carnivorous fish that might eat them were swimming in cordoned-off chambers, close enough that the damsel fishﾃつ�could see and smell them but physically blocked from being able to attack the damsel fish. The latter, seeing and smelling danger, quickly performed their false-eye trick.