Cyborg Grasshopper

 by Esme Kelly

(image: New Scientist)

Recently I was talking to a friend of parents who said they had read something about cyborg grasshoppers, of course hearing those 2 words said together was not only quite amusing but caused my curiosity to peak. So later I decided to look it up online and there I found loads of information about it which I thought was very interesting. It turns out they are using these cyborg grasshoppers to help detect explosives. 

 

Researcher Barani Raman and his colleagues at Washington University in Missouri have tapped into the olfactory senses of the American grasshopper, to create biological bomb sniffers. The reason they have done this is because in insects the olfactory receptor neurones in their antennae detect chemical odours in the air. In turn, these neurons send electrical signals to a part of the insects brain known as the antennal lobe. Each grasshopper antenna has approximately 50,000 of these neurons. So to test bomb-sniffing ability, the team puffed vapours of different explosive materials onto grasshopper antennae, including vapours of trinitrotoluene (TNT) and its precursor 2,4-dinitrotoluene (DNT). As controls, they used non-explosives such as hot air and benzaldehyde, the primary component in the oil of bitter almonds. By implanting electrodes into the antennal lobes of grasshoppers, the researchers found that different groups of neurons were activated upon exposure to the explosives. They analysed the electrical signals and were able to tell the explosive vapours apart from non-explosives, as well as from each other.

 

The team fitted grasshoppers with tiny, lightweight sensor backpacks that were able to record and wirelessly transmit the electrical activity of their antennal lobes almost instantaneously to a computer. The grasshoppers continued to successfully detect explosives up to seven hours after the researchers implanted the electrodes, before they became fatigued and ultimately died. Although a little unethical, perhaps thi could be a new way to save thousands of lives in the future.