Beyond the stick insect: the vast dimension of mimicry

Madrid, June 8 (EFE).- Mimicry, one of nature's most fascinating and complex phenomena, continues to be constantly updated with the discovery of new examples and is now opening up to other fields of research, such as genetics, which make it a vast subject of study.

Madrid-based biologist Diana Compte has compiled the essential details of this "art of deception" in the 250 pages of "Mimicry. Genetics and Natural History," a book published by Guadalmazán, under the premise that "imitation is not a mere visual spectacle, but a sophisticated evolutionary tool."

"There's so much left to discover. My idea was to go beyond the most well-known, like the stick insect, and talk about the many cases that exist among animals, plants, and even fungi, to realize the wealth we have," Compte said in a conversation with EFE about his work, one of the few in Spanish on this topic.

The definition of mimicry, and its distinction from camouflage, is a challenge not definitively resolved by science.

"There's controversy because there are actually many specimens that walk a fine line," says Compte. For her, mimicry is when one species imitates another, and camouflage is when it attempts to blend in with its surroundings, as chameleons and lions do.

The mimic always seeks to gain an advantage. It can imitate the objects around it, the plants it lives on, or other animals. This is what orchids do when they pretend to have an insect inside, or the corpse flower when it gives off a nauseating odor to attract pollinators, or the Indian leaf butterfly, "one of the most perfect examples in the animal kingdom."

Mimicry can be practiced in groups, as is the case with the beetle 'Meloe franciscanus', whose eggs, grouped by the hundreds, imitate the shape of a bee.

It can be performed by both predators and prey. There is also automimicry, when one part of an individual imitates another part of themselves.

There is chemical mimicry (emission of substances similar to those of other species), behavioral mimicry (ant-mimicking spiders), and vocal mimicry, which is relatively unknown. One example: the chicks of the burrowing owl make a rattlesnake-like noise to scare away predators.

The "most typical" reasons for camouflaging, explains Compte, are two: "I'm harmless and want to appear dangerous, or, on the contrary, I want to get close to prey, for example to eat it, without it noticing."

The octopus, an expert

Cephalopods are "great specialists" in mimicry and camouflage. Capable of changing color, shape, and behavior, the combination of patterns is almost endless. The Indonesian octopus, described only in 1998, mimics up to 15 different species, from jellyfish to lobster.

In the case of plants, how can they imitate if they cannot see?

"Because they do communicate," says Compte, who cites Italian botanist Stefano Mancuso to talk about "chemical messengers" that humans don't perceive, but plants do.

What appears to be an act of will by a living being to mimic itself is, in reality, the result of a complex evolutionary process.

"It's true that what we call instinct may play a role in mimetic behavior. But what exists is a genetic tendency, which is still unknown in most cases, although studies are being conducted. Genetics is fundamental, and the important thing is to unite the two areas: the natural world with biochemistry and genetics laboratories, the entire molecular dimension," says Compte about the eternal division between "boot and gown."

"If Darwin and Mendel had met..." he fantasizes.

Mimics, he points out, teach that not even a mutation is necessary for the environment or diet to cause two individuals with the same DNA to manifest differently. "It's the same information, but with different day-to-day characteristics."

The author mentions among her favorite mimics the cotinga cinchero, a bird native to South America whose chicks imitate a caterpillar to protect themselves from predators.

"I like it because it's a vertebrate, which seems to be the 'top' of evolution, which imitates an invertebrate. But in nature, there are no inferiors or superiors," he says.

Over time, not only are new species of mimics being discovered, "especially in Southeast Asia," but also fossil material, perhaps of extinct species, that had been unidentified in science museums "for 150 years," says Compte, who closes the book with a phrase that, in light of his study, is beyond dispute: "Mimics deserve special attention." EFE nam/crf