We vertebrates think we're so smart, and we are, comparatively speaking. But that doesn't mean other members of the animal kingdom aren't capable of complex learning — even the ones that eat their mates and have eyes that look like fencing masks.
New research based on one man's observations on his nightly trip to a rooftop garden to watch a male Asian praying mantis (Hierodula tenuidentata) hunt fish suggests that we might not give invertebrates — at least not praying mantises — the credit they deserve when it comes to complex problem-solving.
For five consecutive nights in a row, researcher Rajesh Puttaswamaiah returned to watch the mantis as it hunted for fish in a little fountain on a rooftop garden in Karnataka, India. The mantis hunted late into the night, and caught and ate at least two guppies (Poecilia reticulata) each evening. This was unusual because no previous scientific evidence points to a mantis's preference for fish (though they've been known to eat them when given fish in a laboratory setting), or even their ability to catch them. The reason for this is primarily that their eyes seem to be made for daytime hunting, and that their vision would probably be too poor to hunt aquatic animals, since water adds a extra layer of complexity to the task.
Puttaswamaiah and his coauthors speculate that mantises might have evolved impressive learning abilities and that the repetitive behavior might have been the result of personal experience, which allowed the mantis to develop its hunting methods and return to a location of previous success. They realized the mantis's nightly fishing vigil means something important about the insect's ability to learn:
"Remembering the prey's abundance in a particular site, in relation to their ease of capture and their nutritional content, could be one important factor of this choice and indirectly influence the individual predator's fitness," said the authors in a press release. "This should be investigated in further studies."