30 September 2005
Vol 309, Issue 5744

About The Cover

Cover image expansion

COVER A male North American barn swallow (Hirundo rustica erythrogaster) displaying his ventral coloration. Males whose feathers are experimentally darkened during the breeding season receive relatively greater reproductive benefits from their mates than in previous breeding attempts, indicating that these color signals are used for continual assessment of mate quality. See page 2210. [Image: Marie Read]