06 May 2011
Vol 332, Issue 6030

About The Cover

Cover image expansion

COVER Skull of the theropod dinosaur Velociraptor mongoliensis (Mongolia) showing the eye socket (4 centimeters across). Analysis of the shape of the eye socket and scleral ring (a bone within the eye) of fossil and extant species suggests that Mesozoic archosaurs were active both day and night. See page 705. Photo: Lars Schmitz, University of California, Davis