I’m always amazed how comfortable cats can make themselves. Admiring this leopard’s beautiful coat got me wondering how animals use color to survive.
I don’t mean domestic animals. People have been selectively breeding animals for specific purposes for millennia. They domesticated sheep for food around 11,000 years ago and dogs for companionship several thousand years earlier. When we see cats and dogs, or horses and pigs, in different sizes, shapes, and colors, that’s all our doing.
Wild animals are a different story. They’re the ones I’m curious about. They’ve survived the fickle demands of life, with survivors passing advantageous traits like color down to their offspring. Turns out, color helps animals survive in several ways, including as camouflage, as a warning to others, as an aid in mating, as a means to resists parasites and insects, as a way to signal to members of the same species, and as a way to regulate body temperature.
Camouflage comes in many guises to aid both predators and prey. The snow leopard hunts in the mountains of Asia and India, in a range that varies from deep snow and lush forests at lower altitudes, to rocks and cliffs above the treeline. They prefer to ambush from above, in the murky light of predawn and early evening. A thick, mottled coat of white, gray, tan, and black permits the snow leopard to thrive in an exceptionally harsh and varied habitat.
Camouflage also aids prey as they seek to avoid detection. One method is by mimicry. The Brimstone Butterfly of Europe and Asia closely matches leaves of the plants in which it hibernates during winter.
Some animals mimic other animals to avoid predation. In the United States, certain kingsnakes and milk snakes, both non-venomous species, exhibit the same red, yellow, and black colors of venomous coral snakes. Predators who fear coral snakes avoid all of them.
In some cases, dangerous species mimic each other. The Viceroy and Monarch Butterflies have evolved almost identical appearances. The milkweed the Monarch ingests makes it poisonous, and both species taste foul, so their shared coloring benefits both.
Poison dart frogs come in a wide array of attractive colors. Don’t be tempted to touch one! One dose of the poison that coats the skin of the Golden Dart Frog, the world’s deadliest frog, will kill 10,000 mice, or two elephants, or 10 to 20 humans. Predators (and, hopefully, you) know to steer clear of these flashy amphibians. But they’re only dangerous in the wild; they eventually lose their toxicity in captivity as they stop eating the insects that make them poisonous.
Incidentally, do you know the difference between venomous and poisonous? Venomous animals like snakes deliver their toxin through bites or stings, while frogs and other poisonous animals transfer the toxin through touch or being eaten.
Wasps employ their own warning colors. How many of you don’t twist in horror when a swarm of red, black, or yellow suddenly buzzes your head? Many times, wasps’ color is directed toward other wasps. Some can advertise their fighting ability through patterns on their faces. Rivals then decide if they have what it takes to start trouble. Colors may also help wasps recognize nestmates.
Scientists disagree whether or not zebras’ stripes help the animals avoid predation. They’re more confident stripes help zebras recognize each other. Every zebra carries a unique stripe pattern, like a primate’s fingerprints. Also, recent studies suggest zebra stripes ward off biting horseflies and tsetse flies, which carry fatal diseases. Stripes may help zebras regulate body temperature, as well.
Regulating body temperature is a major reason why lizards like the Bearded Dragon change colors. They darken their backs to brown during cooler weather, which helps them absorb light and raise their body temperature. When too hot, they change back to light-reflecting yellow. Bearded Dragons can change the color of their chests and beards, too, but that response is seen only during social interactions.
Many animals rely on colorful displays to attract mates. The Magnificent Frigatebird, a large seabird native to tropical and subtropical American waters, is a fine example. During mating season, males collect in groups of up to 30 as females circle overhead. The males puff up normally hidden bright red throat pouches, throw back their heads, and stretch their vibrating wings outward to show the lighter shaded feathers underneath. Females swoop down to choose and the new pairs entwine their bills to seal the courtship.
Animals take advantage of color in many different ways to survive. The most extreme example might just be the humble lobster. Every once in while, you hear about a blue one being caught and how the odds of that happening are one in two million.
The odd color is due to a genetic mutation that causes the lobster to produce too much of a certain protein.
Other weird lobsters have shown up recently. The catch of a Yellow one is estimated to be a one in 30 million occurrence. Then, in 2011, fisherman netted an albino lobster that researchers believe happens only once out of every 100 million hauls.
The crews catching these lobsters rightly feel touched by luck. But how lucky are the blue, yellow, and white lobsters? I’ve never once heard of one ending up in a pot of boiling water.
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“Brimstone Butterfly (Gonepteryx rhamni).” Wikipedia.
Crew, Bee, “This Dead Leaf Butterfly has a dazzling Secret,” Australian Geographic. 10 Sep 2018.
Durham University, “Humans are the Reason Why Domestic Animals Have Strange and Varied Coat Colors,” Physorg.com. 16 Jan 2009.
“Golden Poison Frog,” Wikipedia.
“How Rare are Bright Blue Lobsters?” BBC News. 25 May 2016.
Lear, Jessica, “Our Furry Friends: the History of Animal Domestication,” JYI. 17 Feb 2012.
Levine, Jennifer, “The Science Behind Animal Coloration,” Cell Mentor. 27 Jan 2016.
Morell, Virginia, “A New Explanation for Zebra Stripes,” Science. 13 Jan 2015.
–“Zebra Stripes Confuse Biting Flies, Causing Them to Abort Their Landings,” Science. 20 Feb 2019.
“Poison Frogs,” Smithsonian.
“Polistes Fuscatus (Northern Paper Wasp),” Wikipedia.
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University of Melbourne, “Bearded Dragons Change Color on Different Body Parts for Social Signals and Temperature Regulation,” Science Daily. 8 June 2016.
University of Michigan, “Animal Coloration Research: On the Threshold of a New Era,” Physorg.com.
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