Why study anatomy?
Because i want to invent figure groupings from imagination and light them convincingly.
Academic drawing is all about control. The way you sharpen the pencil,the way you hold it,the paper you use. How to use an eraser, a plumb line, calipers, and so on to setting out a palette.
A drawing has several stages of development. It begins with simplified anatomy to establish the balance,action and proportion. Rib cage, pelvis,skull, shoulder girdle ,spine, arms and legs….all just simple shapes and long lines. And if its wrong its going to be wrong a week later, so fix it. Now. This applies whether you start with the gesture or envelope approach.
We all know enough anatomy to get this far. Even inventing compositions of several figures.
Then begins the counterchange of curves,all of which are convex,working one side of the torso then the opposite.the same applies to the limbs. The back of the arms and front of the legs can be shown as a single curve,with a bump for knee or elbow,the complexity is on the other side( eg deltoid biceps, extensor group,radius).
Most of you are still with it,although the knees and elbows are a bit shonky,and the shoulder girdle is becoming a worry.
And just where is the light coming from?
Now its time to block in the shadow shape. In academic drawing the lighting always has a strong,single source. To delineate the form shadow we must conceive the figure as geometric forms(cylinder, sphere, ovoid, block) for the light cuts across. Soft transition on slowly curving form,abrupt transition elsewhere. The sharpest edge and darkest tone is in the cast shadow. Then there is the shadow cast on the other figures and surfaces.
If you have come this far you are probably suffering from” what is that bump?” And” what shape is the shadow?”And vowed to learn more. But a warning. There is always more.
It is one thing to draw this from observation, but when called upon to invent a figure your knowledge of anatomy is really challenged. The blocking of the form shadow edge is where we can fudge it no longer. You cant go looking up charts in a 10 minute pose. Your knowledge needs to be good enough to allow seamless drawing, whether from life,photo or imagination.
So learn anatomy,but learn it well.