A morbid discovery in the botanical world was recently made when a University of Tokyo researcher identified a plant species that mimics the scent of dead and wounded ants to attract pollinators in a complex scheme that leverages multiple links in the food chain.
The new study suggests that the plants were imitating the ant smell, not to attract ant predators, but rather to lure flies that steal the dead ants’ discarded food. By attracting the flies, the dogbane species Vincetoxicum nakaianum would achieve cross-pollination, as explained in a new study published in Current Biology.
Evolutionary Advantages
The new research presents evidence for floral mimicry well beyond earlier expectations. While no plant has ever been reported to mimic ants before this latest research, such an ability has been documented in multiple invertebrate species. The evolutionary benefit of mimicking ants is enormous, as the tiny insects are both widespread and a food source for many other species. By mimicking ants, lifeforms will attract ant predators and related creatures for various reasons.
Several other varieties of mimicry have been recorded in animal species. Predators may use aggressive mimicry to resemble a harmless or even desirable object to lure in their prey. Another type is Batesian mimicry, in which a harmless creature mimics the appearance of a toxic one to avoid predators. Similarly, some beings exhibit Mullerian mimicry, in which multiple truly toxic species resemble one another to give a warning to predators that they are not to be eaten.
An Accidental Discovery
Ko Mochizuki, the study’s author, drew on training from a 2019 intensive course when he first observed flies swarming around dogbane. He connected this behavior with earlier research describing chloropid flies that pollinate plants emitting insect-like odors.
“I was working on another research project,” Mochizuki explained, “and originally collected this species only as a ‘reference’ for comparison. By chance, I noticed chloropid flies gathering around its flowers in the nursery in the Koishikawa Botanical Gardens, and immediately realized that the flowers might be imitating dead insects.”
Mochizuki decided to follow up on the potential connection by conducting a careful observation of the creatures drawn to the flowers and comparing the odors of the flowers to those of different insects. The scent was highly specific: not just the smell of ants, but of ants being attacked by spiders.
The strange correlation presented new questions, though. No earlier research suggested that chloropid flies were interested in ants hunted and injured by other species, so why would the smell attract them now?
Citizen Science Pollinator Data
To answer this, Mochizuki enlisted citizen scientists, who documented flies stealing food from ants attacked by spiders—a kleptoparasitic behavior. He later confirmed these findings with further behavioral observations.
“That moment, when I saw the flies on the flowers, was truly one of inspiration,” Mochizuki recalled, “a hypothesis suddenly taking shape. This experience taught me that unexpected discoveries often emerge from a combination of preparation and chance.”
Mimicry is a widespread evolutionary strategy, and Mochizuki now plans to investigate its role in greater depth.
“I would like to investigate the evolutionary background of ant mimicry by comparing the pollination systems, evolutionary history, and genetic makeup of Vincetoxicum nakaianum and its close relatives,” Mochizuki said, adding that he hopes to examine similar instances that might be revealed in other species, “both within Vincetoxicum and in unrelated plant groups, to uncover further examples of potential mimicry.”
The recent paper, “Olfactory Floral Mimicry of Injured Ants Mediates the Attraction of Kleptoparasitic Fly Pollinators,” appeared in Current Biology on September 24, 2025.
Ryan Whalen covers science and technology for The Debrief. He holds an MA in History and a Master of Library and Information Science with a certificate in Data Science. He can be contacted at ryan@thedebrief.org, and follow him on Twitter @mdntwvlf.