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Meet the Masters of Disguise

Meet the Masters of Disguise, the Science Mill’s newest exhibit opening December 21. Bringing together live animals and STEM interactives, this temporary exhibit invites you to take a closer look at the ways that animals blend in, stand out, confuse the eye or hide in plain sight.

 

“Camouflage comes in many forms, but they are all about survival,” explained Zac Zamora, Science Mill Creative Director. “Animals need to avoid predators, secure food and attract a mate. Features that help them survive get passed onto future generations.” A visit to the Science Mill’s axolotls illustrates this idea. “Compare an albino axolotl with its darker tank mate,” suggests Lisa Keys, Science Mill Animal and Plant Care Technician. “While they’re bred as popular pets, it is unusual to see an albino axolotl in the wild—they rarely survive.”

Extreme adaptations allow animals to masquerade as other objects in their environments. Covered in lumpy growths, a Vietnamese mossy frog hopes that predators will overlook it as just another clump of moss. Similarly, a giant African stick mantis “becomes” a branch by stretching out its twig-like limbs. The jeweled flower mantis uses this strategy to hunt: unsuspecting insects that wander near are suddenly snatched up by a hungry “leaf.”

For animals who rely on blending in, movement can blow their cover. “Mantids and chameleons disguise their movements, too,” Lisa observed. “They will rock back and forth in the middle of each step to match the swaying leaves around them.”

Scientists think some patterns help to camouflage animals in motion. On the run, a zebra’s stripes may confuse a predator and make it harder to track its path. High-contrast patterns, like black and white, visually break up an animal’s shape. “Militaries borrowed this idea during WWI,” Zac noted. “Ships were painted with ‘dazzle’ patterns to make it harder to gauge their speed and direction for planning an attack.”

 

To test theories about stripes, scientists in England created a video game. Instead of lions and zebras, humans try to capture “dazzlebugs” with varied patterns. You can try out the Dazzlebug game at the Science Mill; each round you play adds new data on which patterns are hardest to catch.

 

The Sinaloan milk snake’s stripes may “dazzle” predators while it slithers away to safety. But as you’ll see in the exhibit, those bold stripes definitely don’t blend in—and that is the point. The brightly colored stripes allow it to impersonate the highly venomous coral snake. “Red, yellow, black and white are warning colors in nature,” said Lisa. “It’s a way to advertise that you are dangerous, so would-be predators stay clear.” In the case of the harmless milk snake, it’s false but effective advertising.

Color-changing chameleons have become synonymous with blending in, but their colors are really about being seen. Panther chameleons use color to communicate: to signal danger, to attract (or reject) a mate and even to battle for turf. Male panther chameleons put on a bright display when they fight; the loser goes dark to say, “I give up!”

The secret to the chameleon’s color change lies in a layer of cells that contain tiny crystals. As a chameleon’s skin relaxes and tenses, these cells bunch together or spread out, causing the crystals to reflect light as different colors. Some octopuses and cuttlefish add another trick: along with light-reflecting cells, a web of muscle fibers lets them change their skin’s texture.

 

Studying how animals produce these dramatic changes inspires scientists and engineers. In the Masters of Disguise exhibit, you can try out panels that change color in response to temperature. A network of nanocrystals, similar to a chameleon’s cells, reflect different colors as they shift from a solid to a liquid and back. It’s a technology used in digital screens. Other materials are still in the experimental phase, such as shape-shifting silicone sheets and panels that automatically change patterns by sensing their environment. “Creating an artificial octopus skin would be an amazing feat,” mused Zac. “It’s a step closer to a real-life invisibility cloak!”

Masters of Disguise will only be at the Science Mill for a limited time, so plan your visit soon!