Everyone knows that the praying mantis gets its anthropomorphic nickname from the fact that they have elongated forelegs which, when folded, makes them look like they’re praying. However, misspelling “praying” as “preying” would not be a mistake. These extremely large flying insects are known for eating birds, amphibians, reptiles, snakes, turtles and, in the case of females in the middle of copulation, inseminating male mantises. Fish have felt safe because they’re neither male mantises nor on the list … until now. Researchers have witnessed the first known instance of a mantis in the wild catching and eating fish. Not only that, it appears they really like fish, are smart enough to know and remember where the big ones are, and can consume enough to alter the ecology of a pond. Is this a movie plot or another insect-driven path to dystopia?
This scary news comes to us from a study published in the Journal of Orthoptera Research, which is actually the wrong place for it since mantises belong to the order Mantodea, not Orthoptera, which is the order of grasshoppers and crickets. Apparently, this discovery was big enough that the Journal of Orthoptera Research made an exception.
“Last year, the team observed an adult male hunting and devouring guppies in a pond located in a private roof garden in Karnataka, India.”
In a press release, the researchers describe seeing a large (5.6 cm/2.2 in long) mantis (Hierodula tenuidentata) walk across the leaves of water lilies and water cabbages, stop at the edge, reach into the water with those lengthy forelegs, catch a guppy and devour it. That apparently was enough and the mantis left, but not before the researchers noted that it had a white antennomerus (antenna segment) on the right antenna. That allowed them to confirm that the same mantis returned to the same pond for another guppy on the next day … and the next … and the next … and the next, for five consecutive days.
Aside from adding a new item to the mantis menu, what’s the big deal?
“Firstly, the fact that praying mantises hunt on vertebrates outside cages in labs confirms that a single invertebrate species is indeed capable of having an impact on a whole ecosystem. In this case, a mantis preys on guppies which, in their turn, feed on aquatic insects.”
This mantis ate 9 of the 22 guppies living in the small artificial pond, which would eventually allow other fish species in it to take over and for insects no longer being eaten by the guppies to thrive. If that’s not scary enough, the mantis did its hunting at night – something they were previously not known to have the night vision to do. Finally, the fact that the mantis left and came back so many times indicates to the scientists that it was capable of learning and remembering ... at least until it loses its head to a hungry, horny female.
“Remembering the prey’s abundance at a particular site in relation to their ease of capture and their nutritional content, could be one important factor of this choice and may indirectly influence individual fitness. This should be investigated in further studies.”
In these days of do-it-yourself home DNA modification kits for making mutant frogs, it’s only a matter of time before someone decides to mess with mantises. Shouldn’t we at least wait until we know more about mantises? What could possibly go wrong?
Whatever the answer, it wouldn’t be long before we became the species doing the praying.