This is one of the strangest shapes ever seen, so much so that I questioned its original shape designation of "Shield" for "Elephant's Foot", but as likely as it seemed, could not hold water in lieu of its unique paneling - the answer, of course, was to ask Adam. Turns out this piece is actually called the "Sparrow", and if you visually eliminate the shank for a minute, a sparrow does in fact begin to appear, albeit rather abstractly. The front panel is meant to mimic the arc of the bird's breast, the side panels representing folded wings, coming to a very precise point on its Dublin/Acorn base.
As you would expect from a "7" grade from Mr. Nielsen, the grain of this pipe is remarkable. You really have to admire Tonni's skill in orienting the grain, while staying true to the "Sparrow" theme: how the "breast" panel is filled with birdseye, creating the illusion of a smoother surface, anatomically similar to the shorter, softer feathers on an actual bird. Likewise, the strands of vertical flame grain patterning down the left and right "wing" flanks, perfectly mimics how a bird's feathers would fall when in a nesting position.