23 June 2017
Vol 356, Issue 6344

About The Cover

Cover image expansion

COVER Birds lay eggs in a diverse array of colors, patterns, sizes, and shapes, as seen in this assortment from the Western Foundation of Vertebrate Zoology collection. An investigation by Stoddard et al. reveals that egg shape is related to flight ability in birds, overturning classic theories. Additionally, the egg’s flexible membrane—not the shell—might be responsible for the great variety of egg shapes. See pages 1234 and 1249.
Photo: © Frans Lanting