Nature reveals a truth with some odd implications about insects’ inner lives. Memory tests prove that bees are more thoughtful than we realize:
“The surprise comes for many people that such a tiny little brain is able to form such a rich memory described as a cognitive map,” says co-author Randolf Menzel, a neurobiologist at the Free University of Berlin.
The cognitive map used by mammals is thought to originate in the brain’s hippocampus. Humans employ such maps on a daily basis; for example, even in a windowless office, many people can point towards their home, orienting themselves in space based on knowledge of their location relative to the outside world.
The authors tested their theory by interfering with the bees’ Sun compass: they shifted the bees’ internal biological clock by inducing sleep using a general anaesthetic. Once the bees had woken up, Menzel and his colleagues tracked them along a path of several hundred metres from a release site to their hive using harmonic radar, which detects and records movement based on transponders fixed to the bees.
When the bees were released from a site with which they were unfamiliar, they initially travelled in the wrong direction, flying away from their hive instead of towards it. With their internal clocks shifted, the bees still thought that it was morning — so they went the wrong way based on their sense of where the Sun should be. “But then they redirect, ignoring the information from the Sun,” says Menzel. “They refer to something else” — which he and his team think is a cognitive map.