10 July 2009
Vol 325, Issue 5937

About The Cover

Cover image expansion

COVER Skeletons of turtle, chicken, and mouse. The turtle body plan is unusual in that the ribs are transformed into a carapace, and the scapula, situated outside the ribs in other animals, is found inside the carapace. A report on page 193 )explains the evolutionary origin of this inside-out skeletal morphology. Drawings: Hiroshi Nagashima