As a follow-up on the Bees on Cocaine post, I give you: Hoppers on Prozac.
Serotonin Mediates Behavioral Gregarization Underlying Swarm Formation in Desert Locusts. Michael L. Anstey, Stephen M. Rogers, Swidbert R. Ott, Malcolm Burrows, and Stephen J. Simpson (30 January 2009) Science 323 (5914), 627. [DOI: 10.1126/science.1165939]
The desert locust is a mid-mannered grasshopper that will suddenly undergo a Jeckyl and Hyde transformation into a (literally) biblical plague of locusts. This new paper has teased out just how that happens!