Gawd, singular, I was thinking the same thing. Art class. The ubiquitous cow skull. Anatomically, excellent. Eye to hand translation -- excellent. What did you learn, would have been my instructors' question. Did you do these by blocking them first with circles, ovals, lines and angles, or did you draw them "cold" -- straight onto the paper? The second way is the harder, of course, but also demonstrates that you have that propensity...which can be developed in those who don't but it takes a long time.