Spiders Evolve Wasp Disguise That Fools Even AI

An Uncanny Resemblance That Deceives AI

Some jumping spiders mimic predatory wasps so well that images of them can fool even sophisticated artificial intelligence. These spiders bear such a striking resemblance to the predatory insects—which, ironically, often prey on spiders—that they are even named after them.

Biologists at the University of Cincinnati were curious: is this mimicry a genuine evolutionary trait, or are we just seeing faces in the clouds? To remove human perceptual bias from the equation, they turned to an objective observer: a computer.

During the COVID-19 travel shutdowns, the research team presented digital portraits of jumping spiders, praying mantises, and wasps to a computer algorithm. The AI, designed to identify shapes and patterns, was surprisingly fooled, misidentifying the spiders in some cases about 20% of the time.

The findings were detailed in a study published in the journal Behavioral Ecology.

The backs of jumping spiders resemble predatory insects like wasps and praying mantises that can fool even AI. Graphic/Olivia Harris with photos by Jurgen Otto

The Wasp Spider: A Master of Disguise

“The original idea was inspired by one species, a peacock jumping spider called Maratus vespa, which is Latin for wasp,” said Olivia Harris, a UC student and the study's lead author.

This particular jumping spider, discovered in Western Australia, performs an elaborate courtship display. The male lifts his abdomen to reveal a colorful, wasp-shaped back. The illusion is enhanced by raising flaps on its sides, perfectly mimicking the distinctive shape of a wasp’s face.

“That got us thinking,” Harris continued. “Why would a spider want to look like a wasp, which is a predator of spiders, especially as a primary element of its courtship display?”

Why Pretend to Be Your Own Predator?

The researchers believe the answer lies in capturing the female's attention. When spiders spot a distant insect predator, they tend to freeze and give the potential threat their undivided focus. This moment of hesitation could provide the male jumping spider with the perfect window of opportunity to begin his courtship ritual.

This is the only case we’ve found of males mimicking a predator visually.

— Olivia Harris, UC doctoral student

While deception is not unheard of in animal courtship—some male moths imitate the sounds of bats, and certain antelopes fake predator warnings—this visual mimicry of a predator by a male is a unique discovery.

UC Associate Professor Nathan Morehouse uses microspectroscopy to study spider vision in his biology lab. Photo/Jay Yocis/UC

The Science of Deception: A Calculated Risk

UC Associate Professor Nathan Morehouse, a co-author of the study, explained that the spiders are using a tactic known as sensory exploitation.

“Sensory exploitation is very common. It fits in a body of theory about how animals use deception or confusion to their advantage,” Morehouse said.

However, the illusion can't last forever, or the female would either flee or attack. The research suggests that the predator disguise works best at a distance or in the female spider's peripheral vision, where she relies on eyes that see only in monochrome green.

As the male gets closer, the female's advanced, front-facing eyes, which can discern color, take over. “Females will not be fooled forever,” Morehouse noted. “It’s beneficial for the males to break the illusion.”

To do this, the male will often lift his front legs. This action cleverly frames his vibrant courtship colors for the female while also hiding some of his more "waspy" features. It's a nuanced dance of deception and display.

“They use predator cues to manage attention and put the female on her back foot — or feet,” Morehouse concluded. “There’s a lot of nuance to this interaction for the males to remain safe and for the courtship to have beneficial outcomes for both.”

UC College of Arts and Sciences Associate Professor Nathan Morehouse studies spider vision in his lab. Photo/Jay Yocis/UC