Contents

30 January 2009
Vol 323, Issue 5914

About The Cover

Cover image expansion

COVER Desert locusts, Schistocerca gregaria, are normally solitary and avoid each other (green individual, lower right). Forced proximity between them leads to the release of the neurotransmitter serotonin, which changes their behavior to mutual attraction and initiates a cascade of events leading to swarm formation, including a change in appearance (black and yellow group). See page627) Image: Tom Fayle, Swidbert Ott, and Stephen Rogers/University of Cambridge