
1. VARIATION You know what’s variable? Apatosaur cervicals. Top: NSMT-PV 20375, cervical 7 in anterior and left lateral views (Upchurch et al. 2005). Middle: YPM 1861, cervical ?13, in posterior and left lateral views (Ostrom & McIntosh 1966). Bottom: YPM 1980, cervical 8 in anterior and left lateral views (Ostrom &






