The Elements of Evolution (49-11-4) Freeloading Mimicry


As the mimic octopus illustrates, safety is not the only reason to mimic. Freeloading is a fine reason for imitative inducement.

The flowers of some species replicate the scent of others that pollinators favor, to attract attention without providing the payoff of nectar. Other flowers mimic the female of a certain insect to compel males to it. Various orchids employ this trick.

 Large Blue Butterfly

Caterpillars of the large blue butterfly practice chemical and auditory mimicry. They feed on thyme or marjoram flowers after hatching, which primes them for the next act.

After molting, a caterpillar drops off the plant to the ground. There it secretes sweetness that attracts red ants. Suckered by sugar, the ants take the larva back their nest.

The ants feed on larval secretions by milking it: stroking the caterpillar with their antenna to have it produce a small drop of honeydew. Having pacified its caretakers, the caterpillar goes into hibernation inside an ant tunnel.

In due course the caterpillar reemerges. It seeks out the nesting chamber, where it spends up to 3 weeks feasting on red ant eggs and larvae. It can do so by secreting a hormone that tells the ants that it is one of them.

The caterpillar also mimics the sound that a queen ant makes, ensuring itself a steady food supply. By this queenly deception ants will even kill their own larvae and feed the caterpillar if food is scarce.

Having matured off the largesse of its inadvertent patrons, the caterpillar hangs itself from the roof of the nest by its legs and builds a chrysalis around itself. The large blue butterfly lives up to 9 months as a caterpillar prior to its pupal stage.

After another 3 weeks, an adult butterfly emerges. The butterfly leaves the nest to find a mate, with but a few weeks left to live.

 Courting Cockroach Counterfeit

A male German cockroach in courtship offers dinner to a prospective mate: he raises his wings, exposing a pantry of deliciousness produced by the male’s tergal glands.

A female mounts a male and feeds on these nuptial secretions. This puts her in position for the male’s sexed solicitude.

Baby German cockroaches caught on. They evolved to vamp what every male cockroach is looking for. A gentle tap with an antenna scented with a knockoff version of femme fertile perfume and a male lets a little counterfeit on board for a free meal.


Humans innately imitate in social settings. Conscious-ly not doing so is stressful. Waiters who repeat customer orders word for word, or subtly mimic a patron’s body language, earn higher tips than those that paraphrase or forgo gestural mirroring.

The evolution of mimicry and polymorphisms depends on how receivers acquire information. ~ English zoologists Rose Thorogood & Nicholas Davies