Bees can be trained to sniff out explosives and cocaine, and here's something else they can be trained to do: tell apart one human face from another, according to a study published in the February issue of Journal of Experimental Biology.
The way to get a bee to choose you to be its friend: droplets of sugar water.
The study's authors placed a sugar solution in front of a picture of simple symbols arranged in a "normal" face-like image - two dots for eyes, a short vertical dash for a nose and a longer horizontal line for a mouth - then rewarded the bee for going to the photo.
Dr. Arian Dyer from Monash University, Dr. Martin Giurfa from the Universite´ de Toulouse, France, and their team conducted the study.
They then added in other dot-dash images to the mix with the symbols cramped together, others with them farther apart, and the bees continuously went to the original photo - the one most face-like and where the reward was given - even after the sugar solution was taken away.
The researchers say this proves that the bee could recognize a specific pattern and remember it as a reward source. But now they wanted to see if the insect could distinguish between more complex, more human-like faces.
Presented with a completely fresh series of images where the dot-dash faces from before were laid on top of photographs of real faces, the bees still favored the real face photo with the original, most face-like dot-dash arrangement on it. Then, when the "dot-dash face" was taken off, still the bees flew toward the real face photo that was organized most like a normal human face.
When the team tried scrambling the real face photos - moving the eyes, nose and mouth - the bees no longer recognized the images as faces and treated them like unknown patterns.
The theory is these intelligent, but incredibly small-brained, insects probably use this facial recognition strategy to learn about the environment around them, because they certainly have no need to remember who we are. Unless they want to bee friends.
Photo credit: U.S. Dept. of Agriculture