Fish

Altering Physical Appearance

Sea creatures of varying species systematically alter their appearance to protect themselves. Stomatopods, commonly referred to as mantis shrimp, are a small sea creature found on ocean floors. They have distinctive means by which they protect themselves. Mantis shrimp are renowned for their folding forelegs, which they use to smash the hard shells of crabs or clams or spear soft bodies of fish. The smashing mantis shrimp needs less than one second to fully extend its claws and can strike with a force likened to a small caliber bullet. Although powerful given its size, the mantis shrimp is vulnerable and weak against a rival when it molts. After shedding the outer shell, mantis shrimp expose a soft underbody and lose their ability to smash or spear. Thus, they are far more susceptible to injury if attacked by predators. To protect themselves during these vulnerable periods, mantis shrimp deceive predators by altering their physical appearance. To appear like a more dangerous threat, mantis shrimp elevate their heads and extend all of their appendages and scales, increasing their apparent size. They also expose brightly colored areas of their body, known as the meral spot. The meral spot is located on the inside of the striking appendage of the crustacean and is used as an indication of increased aggression by the signaler. Although without their protective shell and unable to follow through with any aggressive action, mantis shrimp attempt to deter and deceive predators about their physical stature.

Siamese fighting fish use physical battles to deceive competitors about their dominance. The aggressive combat of Siamese fighting fish can result in damage or even death to the weaker opponent. Given the dire consequences of some of the more violent battles, Siamese fish alter their appearance to deter competitors from waging war in the first place. To maintain a dominant guise, Siamese fighting fish pick fights with “losers” of previous physical encounters. They identify the weaker fish by eavesdropping on other battles. That is, they watch others' battles to determine the hierarchy of dominance.

When later approached for battle, the Siamese fighting fish choose to fight the weaker fish that previously lost a battle. Moreover, Siamese fighting fish increase such aggressive actions against weaker competitors when an audience is present, as if publicly displaying their dominance. Siamese fighting fish selectively pick opponents in fights in order to deceive competitors, maintain dominance, and increase survival rates.

Manipulating Others' Preferences

Like many other species, fish go to great lengths to protect their young from predators, particularly when their young are most vulnerable. For instance, the three-spined stickleback fish use deceptive strategies that attempt to manipulate the preferences of predators. Male sticklebacks stand guard at the entrance to their nest while the eggs develop and hatch. If others approach, sticklebacks attempt to manipulate predators' preferences for food sources. Sticklebacks provide false [Page 386]information about the location of their nest. They may bury their own nest in sand. They use distraction displays to deflect predators from the nest. To suggest nutrition lies elsewhere, sticklebacks swim to a more remote area and feign feeding. If provided with the opportunity, stickleback fish might also feed or feign feeding on eggs from another nest to mislead predators about the location of their own young. Sticklebacks also act in ways that suggest they are eating their own young in order to manipulate predators' beliefs about the number of eggs that remain in that nest. Although these displays can be learned by the predators and may lead to the capture of eggs, the stickleback's deceptive tactics that aim to manipulate the preferences of predators increase survival rates of their young.

...