A team of biologists and robotic researchers from Australia and Germany has solved a mystery of how wasps make sure that they find their way home.
The team, led by Prof. Jochen Zeil of the Australian National University, analyzed learning flights in ground-nesting wasps (Cerceris australis) using synchronized high-speed cameras.
The scientists found wasps gather views of their environment during the flights each day with their focus always on their nest to ensure they know the way home after foraging.
“The learning and homing abilities of wasps make them smarter than anything humans know how to build,” Prof. Zeil said.
He and his colleagues created a wasp’s eye view, using 3D models and stereo cameras, so they can understand why wasps gather certain information during learning and homing.
“Wasps move along arcs centered on the nest entrance, whereby rapid changes in gaze assure that the nest is seen at lateral positions in the left or the right visual field. Between saccades, the wasps translate along arc segments around the nest while keeping gaze fixed,” the scientists said.
Wasp Cerceris sp. Image credit: Charles James Sharp, www.sharpphotography.co.uk / CC BY-SA 3.0.
“We reconstructed panoramic views along the paths of learning and homing wasps to test specific predictions about what wasps learn during their learning flights and how they use this information to guide their return.”
“Our evidence suggests that wasps monitor changing views during learning flights and use the differences they experience relative to previously encountered views to decide when to begin a new arc,” they said.
“Upon encountering learned views, homing wasps move left or right, depending on the nest direction associated with that view, and in addition they appear to be guided by features on the ground close to the nest.”
The findings were published online this week in the journal Current Biology.
“It will be important now to investigate whether and to what extent our findings generalize to the learning and homing flights of other insects,” Prof. Zeil and co-authors added.
“It also remains to be understood how the near-goal learning choreography we have analyzed here transitions into the landscape-wide exploration flights, as they have been recorded with harmonic radar in honeybees and bumblebees.”
The scientists hope that their findings will assist with the development of autonomous flying robots.
“Ground-nesting wasps navigate using panoramic vision which generates a lot of information at low resolution,” Prof. Zeil explained.
“Roboticists look to replace expensive high resolution cameras and reduce power consumption without losing information that is crucial for visual navigation and our research could help with this.”
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Wolfgang Stürzl et al. How Wasps Acquire and Use Views for Homing. Current Biology, published February 11, 2016; doi: 10.1016/j.cub.2015.12.052
