Guess the Cover of American Laboratory November/December 2012

Correctly identify this month’s cover image and be entered to win a $10 Amazon gift card (one entry per person; you must be 18 years of age to be eligible. See contest rules at

This sample comes from one of the most recognized of its extinct clade, specifically from the formations that make it so recognizable. There is much debate among paleontologists as to whether these formations were used for combat or courtship. The image was captured at 400× magnification using brightfield microscopy.

What do you think it is? Enter by leaving your answer in the comments section below. Stay tuned for the answer and for next month’s cover image!