Why the cannibalistic behavior of locusts is exemplary

Locusts not only devour fields bare within seconds, but also eat each other. Therein lies an opportunity and a practical parable.

Ulrich Seidler

A grasshopper eats a conspecific.MPI for Chemical Ecology/Benjamin Fabian

The swarming behavior of locusts is not based on the individuals following one another – like migratory birds, for example – but on fleeing from one another. The daily distances of up to 150 kilometers that the swarms cover are therefore driven by fear. The locust’s fear of its own kind is justified because it exhibits cannibalistic behavior at certain stages of its life. From a dialectical point of view, the swarm is also appetite-driven.

Apparently, the crops they eat away from people, as was the case in South Asia and East Africa in 2021, are not enough for them. A swarm eats up entire fields within seconds, enough to feed 35,000 people in one day. The grasshopper is correspondingly unpopular. Her work found its way into the Bible as one of the ten plagues and she has to serve as a metaphor for the greed of unleashed financial capitalism.

A swarm of desert locusts during a plague in East Africa in 2020AP

Researchers at the Max Planck Institute for Chemical Ecology Jena have now discovered that the pheromone phenylacetonitrile inhibits the locusts’ appetite for each other. To remove this inhibition, the researchers used genome editing at two points: they modified the animals in such a way that they could no longer produce the scent, and they switched off the responsible receptor, which must have been a crazy fiddly job.

The goal would be to get the pests to eat each other before they become a nuisance. The matter would be further promoted if the animals were brainwashed to take away their fear of each other. In recourse to the capitalism metaphor, new possibilities arise for the applied and sustainable fight against greedy gorges, which simply disappear into one another in a very relaxed manner.