(Almost) Everything We Know About the Orchid Mantis is Wrong

Luc Viatour, Wikimedia Commons // CC BY-SA 3.0

Orchid mantises, as the name suggests, look a lot like orchid flowers. The insects trade the drab colors and sharp angles of their cousins for bright floral shades and a rounder, softer shape, giving them an uncanny resemblance to delicate petals. When Western scientists first encountered them in Southeast Asia in the late 18th century, more a few mistook them for carnivorous plants at first glance.

Naturalists soon began describing the insect as an aggressive mimic that uses its floral disguise to hide among orchids and devour bugs that come to pollinate them. Over the last 200 years, this idea has become enshrined as fact in textbooks and nature documentaries. There’s one hitch, though—there’s little to no evidence that it’s true.

The bug was and still is rare, and with few specimens to study, 18th and 19th century scientists based their conclusions on just a handful of observations and accounts from travelers. Whether or not the mantis actually mimics flowers and which flower it bases its supposed disguise on are questions that haven’t been experimentally tested until now, and a series of recent studies suggests that we’ve had the mantis’ M.O. pretty wrong this whole time.

The naturalists of yore had at least one thing right. In 2013, Australian biologists (including Marie Herberstein, who has done lots of cool work on animal liars) confirmed that the orchid mantis really does mimic flowers to attract prey, and it’s the first animal known to do that. But a pair of follow-up studies by the same researchers show that the mantis’ hunting strategy doesn’t quite work the way we thought it did. 

For one thing, the mantises don’t need to hide among flowers for their mimicry to work, and they can attract prey just fine on their own. In one study, the researchers found that the mantises don’t have a preference for hunting near flowers or on plain green leaves, and that their hunting success doesn’t differ between the two spots. Being near flowers isn’t necessary to grab a meal, but it does benefit a mantis because abundant flowers mean there will be more prey around. 

The real surprise, though, is that the orchid mantis doesn’t look much like an orchid to anyone but us. In a second study, the team used what scientists know about animals’ visual systems to compare the mantis’ shape and color to different flowers from the perspective of different prey bugs and predatory birds. While early accounts of the orchid mantis often compared it to a handful of plant species that grow in the same forests, the study found that from the point of view of the animals that it’s trying to fool, the mantis doesn’t resemble an orchid or any other specific flower. Instead, it has a generalized “flower-like” appearance that isn’t a perfect mimic of a single species, but a close approximation of several different ones. This might be embarrassing for generations of scientists who thought they knew a thing or two about orchid mantises, but it works out alright for the bugs, the researchers say, because it allows them to fool a wider range of prey and its own predators.