Chemical in human brain behind locusts’ swarming

London, January 30: The usually inhibited desert locusts can turn into horrifying swarms due to a chemical commonly found in people’s brain, a research showed.

The finding published in the journal “Science” revealed that solitary desert locusts undergo drastic change to form terrorizing swarms due to an increase in the chemical serotonin, which affects mood, appetite, sleep and memory in humans.

Swidbert Ott from the University of Cambridge in England and co-author of the study said, "Serotonin profoundly influences how we humans behave and interact, so to find that the same chemical in the brain is what causes a normally shy anti-social insect to gang up in huge groups is amazing."

The research which was led by Michael Anstey from the University of Oxford observed the relationship between the locusts’ behavior and chemicals in their body. One chemical they observed was serotonin and they observed that this chemical increased by three times when the locusts were swarming as compared to when they were alone.

To further prove their findings, the researchers injected serotonin into some locusts. Upon doing so, the locusts exhibited changes in their appearance and began to gather together.

Malcolm Burrows from the University of Cambridge said, "Here we have a solitary and lonely creature, the desert locust. But just give them a little serotonin, and they go and join a gang."

The researchers were also able to find out the reason why the locusts increase their serotonin production. The increase is caused when the locusts are grouped and stimulated by the sight, smell and touch of other locusts, which often happens when their food supply is decreased.

Another reason for the increased serotonin production is stimulation of the insect’s hind legs which happens when they crawl over each other.

Because the change is identified, the researchers were then able to prevent the locusts from changing by giving them drugs that can inhibit serotonin production.

Anstey remarked, "To actually be able to stop it from happening, that was very exciting."

This study which was sponsored by the Biotechnology and Biological Sciences Research Council of England, England's Royal Society, the Australian Research Council Federation and the Natural Sciences and Engineering Research Council of Canada, can provide an answer to the problem on locust infestation.

These creatures currently affect 20 percent of the world and in the last few years, swarms of locusts have plagued China, Africa and Australia.